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MICROBIOLOGICAL CORROSION OF METALS- MARINE WOOD BORERS- RODENT ATIACKS ON STORED PRODUCTS- FOULING OF SHIPS BY BARNACLES- DETERIORATION OF STONE BY BACTERIA­ROTIING OF WOOD BY FUNGI- BACTERIAL BREAKDOWN OF ASPHALT- MILDEWING OF LEATHER -INSECT DAMAGE TO BOOKS -BIRD HAZARDS TO AIRCRAFT- FUNGI IN JET FUEL TANKS­TERMITES IN TIMBER- MICROBIOLOGI~AL ATIACK ON RUBBERS PLASTICS AND PAINTS,- FUNGAL ETCHING OF GLASS ....

INTERNATIONAL

BIODETERIORATION

BuLLETIN

A QUARTERLY JOURNAL OF BIODETERIORATION

BIODETERIORATION INFORMATION CENTRE

THE UNIVERSITY OF ASTON IN BIRMINGHAM •

ENGE.AND

CATOMANCE LIMITED

manufacturers of

mystox* for the preservation of

timber, textiles paper, cordage

plastics and specialised applications

* mystox is the registered trade mark of

Catomance Limited 94 BRIDGE ROAD EAST, WELWYN GARDEN CITY,

HERTS., ENGLAND. Telephone: Welwyn Garden 24373/8

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EDITORIAL STATEMENT

There will be four issues of the International Biodeterioration Bulletin in 1969 and subsequently. This quarterly production has been necessitated by the increasing number of useful articles submitted for publication, by the need to quicken the transference of information from authors to readers and by subscriber requests. The price of the Bulletin will be maintained at £1 per issue, the annual subscription thus becoming £4 ($10) for four issues.

IBBRIS [International Biodeterioration Bulletin Reference Index Supplement] will now cost £4 ($10) per year for four issues, instead of the previous subsidised price of £1 per year. The new cost covers the new printing charges, but not the cost of gathering and processing the information, nor the enquiry services, which are still subsidised.

The Combined Annual Subscription for four issues of the International Biodeterior­

ation Bulletin and four issues of IBBRIS is £6 ($15) per year.

It gives great pleasure to acknowledge the support of the Sustaining Associates and Co-operating Specialists, who have so materially aided in the production of these publications.

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VolumeS Spring 1969 Number 1

INTERNATIONAL

BIODETERIORATION

BuLLETIN

CON'J:ENTS

NEWS AND COMMENT

FUNGICIDES AND BACTERICIDES FOR USE IN RUBBER B. J. Rytych

ASSESSMENT OF PAINTS FOR FUNGUS RESISTANCE E. Hoffmann

1-2

3-8

9-14

A SIMPLE METHOD FOR THE ASSAY OF THE CELLULOLYTIC ACTIVITY OF FUNGI 15-20 J. H. Walsh and C. S. Stewart

THE UTILIZATION OF N-ALKANES BY PSEUDOMONAS AERUGINOSA UNDER CONDI­TIONS OF ANAEROBIOSIS I. PRELIMINARY OBSERVATION R. W. Traxler and J. M. Bernard

21-25

A NOTE ON ENDOGENOUS AND BIODETERIORATIVE FACTORS IN THE RESPIRATION 27-30 OF DORMANT YAM TUBERS D. G. Coursey and J. D. Russull

BOOK REVIEWS 31-36

TABLE DES MATIERES

Nouvelles et commentaires 1-2

FONGICIDES ET BACTERICIDES A L'USAGE DU CAOUTCHOU 3-8 B. J. Rytych

EVALUATION DES PEINTURES RESISTANT A L'ATTAQUE PAR LES CHAMPIGNONS 9-14 E. Hoffmann

UNE METHODE SIMPLE DE CONTROLE DE L'ACTIVITE CELLULOLYTIQUE DES CHAM- 15-20 PIGNONS J. Walsh etC. S. Stewart

L'UTILISATION PAR PSEUDOMONAS AERUGINOSA DES N-ALKANES DANS DES CONDI- 21-25 TIONS D'ANAEROBIOSE. I. OBSERVATIONS PRELIMINAIRES R. W. Traxler et J. M. Bernard

NOTE SUR LES FACTEURS ENDOGENES ET DE BIODETERIORATION DU TAUX DE 27-30 RESPIRATION DES TUBERCULES D'IGNAME A L'ETAT DORMANT D. G. Coursey et J. D. Russutl

Revues des livres

INHALT

Nachricbten uod Kommentar

FUNGIZIDEN UNO BAKTERIZIDEN FOR DEN GUMMIGEBRAUCH B. J. Rytych

PROFUNG DER WIDERSTANDSFAHIGKElT VON FARBEN E. Hoffmann

31-36

1-2

3-8

9-14

EIN EINFACHES VERFAHREN ZUR PR0FUNG DER CELLULOLYTISCHEN AKTIVITAT 15-20 VON PILZEN J. Walsh und C. S. Stewart

DIE NUTZUNG VON N-ALKANEN DURCH PSEUDOMONAS AERUGINOSA UNTER 21-25 ANAEROBEN BEDINGUNGEN. I. VORLAUFIGE BEOBACHTUNG R. W. Traxler und J. M. Bernard

EIN KURZER BERICHT OBER ENDOGENE UNO DURCH ORGANISMEN HERVOR 27-30 GERUFENE EINFLOSSE AUF DIE ATMUNG VON RUHENDEN JAMSWURZELKNOLLEN D. G. Coursey und J. D. Russutl

Buchbesprecbungen

CONTENIDO

Nuevas y comentarios

LOS FUNGICIDAS Y LOS BACTERICIDAS EMPLEADOS PARA EL CAUCHO B. J. Rytych

AVALUACI6N DE LAS PINTURAS PARA LA RESISTENCIA A LOS HONGOS E. Halfmann

31-36

1-2

3-8

9-14

UN METODO SENCILLO DE INDAGAR LA ACTIVIDAD CELULOLITICA DE LOS 15-20 HONGOS J. Walsh y C. S. Stewart

LA UTILIZACI6N DE LOS ALKANES N POR PSEUDOMONAS AERUGINOSA BAJO LAS 21-25 CONDICIONES DEL ANAEROBIOSIS. I. OBSERVACI6N PRELIMINAR R. W. Traxler y J. M. Bernard

APUNTES SOBRE LOS FACTORES END6GENOS YBIODETERIORATIVOSENLARESPIRA- 27-30 CI6N DE LOS TUBERCULOS INACTIVOS DEL YAM D. G. Coursey y J. D. Russutl

Revistas de libros

ii

31-36

ACKNOWLEDGMENTS TO SUSTAINING ORGANISATIONS Financial support for the International Biodeterioration Bulletin from the following organisations is

gratefully acknowledged: ALBRIGHT & WILSON (MFG) LTD., Oldbury

Division, P.O. Box 3, Oldbury, Warley, Worcs. AVON RUBBER COMPANY LIMITED, Melk­

sham, Wiltshire; manufacturers of tyres and mis­cellaneous rubber products.

BEECHAM GROUP LIMITED, Toiletry Division, Beecham House, Great West Road, Brentford, Middlesex.

BORAX CONSOLIDATED LIMITED, Borax House, Carlisle Place, London, S.W.l. (Tel. VIC­toria 9070) ; miners, refiners and suppliers of borax, boric acid, boron ores, boron products and allied chemicals.

B.D.H. CHEMICALS LIMITED, Laboratory Chemi­cals Division, Poole, Dorset; manufacturers of laboratory chemicals, biochemicals, industrial fine chemicals and microbiocides.

BRITISH INSULATED CALLENDERS CABLES LIMITED, 38 Wood Lane, London, W.l2.

THE BRITISH PETROLEUM COMPANY LIMITED.

B.X.L. PLASTICS MATERIALS GROUP LIMITED, Tyseley, Birmingham.

CADBURY BROTHERS LIMITED, Bournville, Birmingham; manufacturers of cocoa, chocolate, cake and milk products.

CATOMANCE LIMITED, Welwyn Garden City, Hertfordshire; manufacturers of speciality chemi­cals for the textile, paper, timber, leather industries, etc., including fungicides, bactericides and insecti­cides.

CENTRAL LABORATORY TNO, Delft, The Netherlands; research, analysis and testing facilities in materials science and technology, including bio­deterioration and marine research. Sponsored by government agencies and by international industries.

CHRIS FOREIGN FOODS WHOLESALERS LTD., Stories Mews, Stories Road, CamberweU, London S.E.5.; tropical foodstuffs importers.

CIBA LIMITED, 4000 Basle 7, Switzerland. COALITE AND CHEMICAL PRODUCTS

LIMITED, P.O. Box No. 21, Chesterfield, Derby­shire; manufacturers of chlorinated and alkylated phenols, phosphate plasticisers and bactericides. Extensive research work and development carried out in all these fields and customer service faciitlies are available for bactericides.

COMMERCIAL PLASTICS GROUP OF COM­PANIES, Industrial Division, Berkeley Square House, Berkeley Square, London W.l.; specialists in the production of film and sheeting in PVC, polythene and high impact polystyrene for all types of applications.

COUR1.'AULDS LIMITED, Coventry. CUPRINOL LIMITED, Adderwell, Frome, Somer­

set; manufacturers of preservatives for wood, tex­tiles, cordage, paper, adhesives, paints, leather, plastics, and paint driers.

THE DUNLOP COMPANY LIMITED. FARBENFABRIKEN BAYER A.G., Leverkusen,

Germany; manufacturers of dyestuffs, industrial chemicals, synthetic fibers, pharmaceutical and agricultural chemicals and preservatives for wood, foodstuffs and technical products.

FISONS LIMITED, Cambridge Division, Saffron

iii

Walden, Essex; makers of agricultural chemicals. Research on control of weeds, plant diseases, spoilage organisms, and agricultural and livestock pests.

FORESTAL INDUSTRIES (UK) LTD. Incorporating Dearborn Pittam and Feedwater Specialists. Both companies are suppliers of industrial water treatment service and chemicals, including a wide range of biocides for control of micro-organisms in cooling water.

GAGLIARDI RESEARCH CORPORATION, East Greenwich, Rhode Island, U.S.A.; sponsored in­dustrial research in textile chemical dyeing and finishing products and processes.

GALLOWAY & BARTON-WRIGHT, Haldane Place, London, S.W.l8.; consultants in industrial microbiology and microbiological deterioration.

GEIGY (U.K.) LIMITED, Simonsway, Manchester, 22.

J. R. GEIGY S.A., Basle, 21, Switzerland; manu­facturers of dyestuffs, industrial chemicals, pharma­ceuticals and agricultural chemicals.

GLAXO LABORATORIES LIMITED, Greenford Road, Greenford, Middlesex; manufacturers of pharmaceuticals, industrial enzymes and fine chemi­cals.

ARTHUR GUINNESS SON & COMPANY DUBLIN) LIMITED.

IDCKSON & WELCH (HOLDINGS) LTD., Ings Lane, Castleford.

IMPERIAL CHEMICAL INDUSTRIES LIMITED, Agricultural Division, Billingham, Co. Durham.

ARTHUR D. LITTLE LIMITED, with offices at Berkeley Square House, Berkeley Square, London, W.l., and offices and laboratories at Inversk Gate, Musselburgh, Midlothian; independent sponsored research organisation.

MAY & BAKER LIMITED, Dagenham, Essex; chemical mannfacturers.

RECKITT & SONS LIMITED, Hull. RENTOKIL LABORATORIES LIMITED, East

Grinstead, Sussex. REVERTEX LIMITED, Harlow, Essex. SCIENTIFIC CHEMICALS INC., 1637 South Kil­

bourne Ave., Chicago, lllinois, 60623, U.S.A.; leading manufacturers of industrial fungicides and bactericides who maintain substantial research and development facilities to assist customers in the development of final products geared to meet government and industry standards.

SHELL INTERNATIONAL CHEMICAL COM­PANY LIMITED.

STAUFFER CHEMICAL COMPANY RICH­MOND RESEARCH CENTER, 1200 South 47th Street, Richmond, California 94804, U.S.A.

VINYL PRODUCTS LIMITED, Butter Hill, Carshalton, Surrey; manufacturers of synthetic resins, specialising in emulsion polymers for ad­hesives, building, paper, surface coating and textile applications.

YARSLEY LABORATORIES LIMITED, Clayton Road, Chessington, Surrey; independent research and testing facilities.

INTERNATIONAL BIODETERIORATION

BuLLETIN Editor

Dr. H. 0. W. Eggins, Biodeterioration Information Centre, Department of Biological Sciences, The University of Aston in Birmingham, Gosta Green, Birmingham 4, England.

Editorial Board

Mr. G. Ayers!, Technology, England.

Department of Biology, College of Wolverhampton, Staffordshire,

Professor G. Becker, Bundesanstalt fur Material­prufting, Berlin-Dahlem 45, Unter den Eichen 86/87, Germany.

Dr. D. S. Belford, Hickson & Welch (Holdings) Limited, Ings Lane, Castleford, Yorkshire, England.

Mr. D. G. Coursey, Tropical Products Institute, 56/62 Gray's Jnn Road, London, W.C.l., England.

Mr. J. J. Elphick, Admiralty Materials Laboratory, Holton Heath, Poole, Dorset, England.

Dr. J. Garrido, Departmento de Fermentaciones Industriales, Castello 25, Madrid, Spain.

Dr. N. E. Hickin, Rentokil Research Laboratories, Felcourt, East Grinstead, Sussex, England.

Dr. H. J. Hueck, Central Laboratory TNO, Schoe­makerstraat 97, P.O. Box 217, Delft, The Nether­lands.

Dr. A. M. Kaplan, Fungicides and Germicides Laboratory, Pioneering Research Division, U.S. Army Natick Laboratories, Natick, Mass. 01760, U.S.A.

Monsieur Y. Le Grand, Centre d'etudes du Bouche!, Vert-le-Petit, (S & 0), France.

Mr. A. 0. Lloyd, Catomance Limited, 94 Bridge Road East, Welwyn Garden City, Herts., England.

Professor R. W. Traxler, Department of Microbiology, University of Southwestern Louisiana, Drawer 1007, USL Station, Lafayette, La. 70501, U.S.A.

Dr. R. Zinkernagel, J. R. Geigy, S.A., CH-4000, Basel 21, Switzerland.

Dr. B. J. Zyska, Glowny Instytut G6rnictiva, Kato­wice, Plac Gwark6w I, Poland.

Publications Editor

Mr. M. J. D. Willsher, Biodeterioration Information Centre, Department of Biological Sciences, The University of Aston in Birmingham, Gosta Green, Birmingham 4, England.

NOTES FOR CONTRffiUTORS

The International Biodeterioration Bulletin is pub­lished four times per year (Spring, Summer, Autumn and Winter). Typescript contributions in triplicate should be sent to the Editor, Dr. H. 0. W. Eggins, at the above address.

The Bulletin acts as a vehicle for the publication of works on all aspects of biodeterioration, i.e. the deterioration of materials of economic importance by microMorganisms, insects, rodents, etc.

Contributions may be in English, French, German or Spanish and should be submitted in triplicate on international A4 size paper (21.0 em x 29.7 em or 8.27 in. x 11.69 in.); typewritten on one side of the paper only. A summary of 25-100 words should accompany each contribution.

Illustrations should be clearly drawn in Indian ink or should be photographed. The reduction desired

'should be clearly indicated and illustrations when reduced are not to exceed 17 em x 26 em. Where figures are to be inserted in the text the approximate position for each one should be clearly marked in the typescript.

iv

The bibliographic references are to be indicated in the text as, e.g.:

Reese and Levison (1952).

and in the bibliography:

Reese, E. T. and Levison, H. G. (1952) Comparative study of the breakdown ofcellulosebymicroorganisms. Physiol. Plant., 5, 354-366.

Authors are requested to abbreviate journal titles according to the conventions of the World List of Scientific Periodicals.

Proofs will not be sent to authors before final publication.

25 reprints will be sent free of charge to each author. Additional reprints are obtainable on applica­tion to the Publications Editor at a charge of £5 ($12) per 100.

NEWS AND COMMENT

It is with great regret that we record the death on 20th February, 1969 of Dr. Ing. Edgar Morath, Professor of the Technical Univer­sity and Secretary General of the International Academy of Wood Science in Vienna.

Dr. Ing. Morath whose subject was wood preservation and who was one of the Biodeterioration Information Centre's Co-operating Specialists was 72.

Dr. W. P. K. Findlay retired at the end of January 1969 from his position as Assistant Director of the Brewing Industry Research Foundation, Nutfield, England. Dr. Findlay was previously Head of the Mycology Section of the Forest Products Research Labora­tory and is the author of a number of books on timber decay and preservation.

Dr. Findlay will now be able to give more time to his consulting practice which is carried on at the address below. His special fields of interest include the preservation of timber, dry rot and woodworm attack in buildings and other structures, and the legal aspects of disputes relating to these subjects.

Dr. W. P. K. Findlay, St. George's Hill, New House Lane, Salfords, Redhill, Surrey, England. Telephone 0293 4 2462.

We should like to congratulate Mr. D. A. G. Isaksson, Ministry of Agriculture, Fisheries and Food Pest OperatorofMontgomeryshire, Wales on the award of the British Empire Medal, announced in the New Year Honours List.

A group of the ASTM (Ameri­can Society for Testing and Mater­ials) Committee on the Corrosion of Metals in the United States is presently conducting measure­ments by electrochemical methods of corrosion rates of five metals and alloys buried in the soil. Three government and three in, dustrial organisations are partici­pating in these tests which will be

completed in about a year. Measurements of soil resistivity, redox potential and pH are being conducted in addition to those of the corrosion rate. Evaluation of this data may provide better under­standing of the anaerobic corro­sion process in which bacteria have been incriminated.

The Ecology Bookshop has re­cently opened at the address below and exists to serve the growing number of people whose awareness and interest in ecology, conservation and related subjects is active in one way or another. Orders from stock can be supplied by return post and any other title available will be obtained on request. A stock list is published which will be revised every six months. Opening hours are 10.00 -19.00 on weekdays and 10.00 -12.30 on Saturdays.

The Ecology Bookshop, 45 Lower Belgrave Street, London S.W.l. Telephone 01-730 8603

The Rentokil Group, formerly a wholly owned subsididary of the private Danish import company, Sophus Berendsen A/S, became a public company in March with an offer of 5,600,000 ordinary shares at a minimum price of 20s. per share. The share price was struck at 25s. and at the end of the first day's dealing (March 18th) the price had risen to 27s. 6!d.

Rentokil's turnover in 1968 amounted to £8,820,000, of which £1,779,000 was accounted for by the group's overseas activities. (Abstracted from The Times).

Karl Winnacker, president of Farbwerke Hoecbst A. G., the chem­ical manufacturers, announced at the end of January that in 1968 his company increased its annual turnover by 19 ·8 per cent to reach DM. 7,980m. (£83lm.). (Abstracted from The Times).

Burmab Oil have made a bid for Major & Co., the oil and petro­leum distributors, and for the 35 per cent of Solignum not already held by Major.

I

Burmah Oil control Atlas Pre­servatives through their acquisi­tion of Castro!. (Abstracted from The Times).

A new type of quick-acting, safe mouse-killer now available to the food trade and general public overcomes mice that are resistant to warfarin and dispenses with the need for prolonged baiting.

This new rodenticide, Alphakil, has been developed by scientists of Rentokil Laboratories Limited and has been successfully used by their pest control teams and by local authorities for the past three years.

Mice are selective in the type of food they eat and are often difficult to control with baits that depend on a cumulative effect over a long period of time. The mouse's· first meal of Alphakil is also its" last. It drops unconscious within feet of the bait and dies as its body temperature quickly falls. The dead bodies are easily recovered for disposal.

Alphakil effectively replaces pre­parations that were prohibited under the Animal Crnel Poisons Act (1964) and it has been welcomed by the Universities Fed­eration for Animal Welfare as being humane in action. Apart from this support, the preparation has been cleared under the Pesti­cides Safety Precaution Scheme of the Ministry of Agriculture, Fish­eries and Food. Alphakil is for use indoors only.

Obtainable from: Rentokil Products Division, Felcourt, East Grinstead, Sussex.

May & Baker Ltd. have developed a new technique for Thin Layer Chromatography, involving the use of the special Chromalay grooved plate, similar to a con­ventional T.L.C. plate, except that it carries near one end and parallel to it, a rounded groove 1·5 mm. in depth. Normal coating equipment can be used to cover the plates with adsorbent, the only difference being that 50 per cent more adsor­bent is needed for grooved plates.

Up to ten times more crude extract can be applied to the grooved plate as opposed to a noma! plate with­out overloading occuring. This is because the layer of adsorbent in the groove is thicker than on the plate itself and there is less tendency for the sample to spread.

Using a method of preliminary separation on the plate itself (which eliminates the necessity for a preliminary clean-up using separ­ate equipment), the sample is brought to a new origin above the groove. The following method describes the technique.

The plate is dipped into a rela­tively volatile solvent ensuring that the solvent level lies a few milli­metres below the bottom of the groove. As the solvent flows up, it carries the more mobile con­stituents of the extract with it. When the solvent front reaches a line 1 to 2 em. above the groove, the plate is removed and the sol­vent driven off; the process is repeated until all the mobile constituents are concentrated in a narrow regular band just above the groove. Use can be made of a shallow covered glass vessel with a longitudinal slit on top to accommodate the grooved plate. This slit is about 1 em. above the groove. As the solvent front reach­es the slit evaporation occurs and the new origin is formed just beyond it.

The advantages of grooved plate T.L.C. over conventional plate are:

up to ten times more crude sample can be applied in the groove without the spreading that would occur on an ordinary plate;

separation and preliminary clean-up are carried out on the one plate, thus eliminating the need for extra apparatus and minimising risk of loss of extract during transfer;

the accuracy of spotting or streaking is no longer critical, so time is saved.

Further details are available from:

May & Baker Ltd., Dagenham, Essex RM10 7XS, England. Telephone 01-592 3060

The latest addition to the "Horo" range of precision ovens, incuba­tors and heating cabinets is the large capacity Horo 700.

With 30 cubic feet of useful space the depth of the oven has been kept to only 2 feet to allow easy stacking of glassware on the shelves. As is usual in uHoro" ovens the interior is of stainless steel. Six Kilowatt heating elements provide fast warm-up and main­tenance of temperature under full wet load conditions, whilst the half heat position can be used for lower temperatures and smaller loads.

Heating of the cabinets is achieved by heating the air stream circulating around the oven and ensures maximum drying rate and even temperature distribution.

The finish of the cabinet is white stoved enamel on steel.

United Kingdom and Eire dis-tributors for "Horo" products are:

Beamcote Ltd., 240 Hurst Road, Bexley, Kent. Telephone 01-300 1498

The World Conference on Bird Hazards to Aircraft is to be held at Queen's University, Kingston, Ontario, Canada on 2nd-5th Sep­tember, 1969. It is hoped to include papers on bird strikes, radar detectionofbirdmovements,identi­fication of bird remains, bird­proofing of aircraft, ecological

2

aspects of the congregation of birds at airports and the dispersal of birds from airports.

Further information can be obtained from:

Mr. M. K. Ward, Conference Secretary, cfo National Research Council of Canada, Building M-20, Ottawa 7, Ontario, Canada.

The Pesticides Group of the Society of Chemical Industry pro­pose to run a three day inter­national Symposium on the Tech­nological Economics of Pest Con­trol at Stirling University, Scotland on 3rd"Sth September, 1969, by invitation of Professor F. R. Bradbury, Director of the School of Technological Economics which is a main interest of this University.

The key-notes of the Symposium will be immediate and long-term objectives in pest control and how existing and future technological resources may be deployed to achieve them. It will discuss the interactions of the economic con­sequences of pests to the individual and to the community-losses of food and social values-with the technologies available to deal with them. This subject requires broad treatment as a background to the problems of making profitable business from manufacture of pesticides and of providing funds for research into alternative meth­ods of control.

Further information from:

Dr. M. B. Green, Hon. Secretary Pesticides Group S.C.I., P.O.Box13, Imperial Chemical Industries Ltd., The Heath, Runcorn, Cheshire, England.

Rytych, Bozena J. Int. Biodetn Bull., 5, (!), 3-8, (1969). Fungicides and bactericides for use in rubber.

FUNGICIDES AND BACTERICIDES FOR USE IN RUBBER Bozena J. Rytych1

Summary This article discusses the fungicides and bactericides used in the past and at present to protect rubber against micro~ bial deterioration. Consideration is given to the advantages of certain fungicides as well as to the fungicidal action of additives in rubber mixtures.

Fongicides et bactCrlcldes it l'usage du caoutchou. Cet article discute les fongicides et bactCricides employ6; au temps passC ct a present pour protCger le caoutchou contre la dCtCrioration microbienne. On considi:re les advantages des certains fongicides et aussi l'action fongicidale des additifs dans des melanges du caoutchou.

I. Introduction

Investigations over the last 30 years have shown that both natural and synthetic rubber may be attacked by bacteria (ZoBell et a!., 1942; Blake et. a!., 1949, 1950, 1953, 1955; Shaposhnikov et. al., 1952; Nette et. al., 1959; Taysum, 1966). Actinomycetales (Sohngen et al., 1914; Spence et al., 1936; Kalinenko, 1938; Rook, 1941; Blake et a/.,1949,1950, 1953, 1955; Shaposhnikov, 1952; Nette et al., 1959) and fungi (Scott, 1920; Kalinenko, 1938; Blake et al., 1949, 1950, 1953, 1955; Nette et al., 1959; Shaposhnikov, 1952; Ross, 1964; Calderon, 1965; Taysum, 1966).

The degree of deterioration of the rubber depends on many factors, of which the chief are:

I. Biological susceptibility oftheindividualconstituents, the polimer, as well as additives (accelerators, curing compounds, fillers etc.).

2. Methods of preparing the raw mixture and the mutual influence of the constituents during the manufacturing processes.

3. Influence of external factors such as temperature, moisture and pH of the environment.

The economic aspects of this problem have been determined by Hueck van der Plas (1965). The annual loss of natural and synthetic rubber due to biological deterioration was estimated f'lr U.S.A. at about 23 million dollars.

2. Requirements for fnngicides and bactericides for use in rubber

Morris and Leslie Ewart (1927) mentioned paranitro­phenol as a fungicide for smoked crepe and rubber sheets and since that time investigations into the selection of useful fungicides and bactericides for rubber have continued up to the present. In biodeterioration of organic materials the best results up to the date have been achieved in the protection of wood. The requirements laid down by Schultze (1939) for wood-preservatives are perhaps the most comprehensive. Having in view his requirements, which may be adapted for every fungicide

Fungiziden und Bakteriziden fUr den Gummigebrnuch. Diese Abhandlung diskutiert die Fungiziden und Bakteriziden ehemals und jetzig gebraucht um den Gummi gegen duren Mikroben veranlasst Verschlechterung zu beschiltzen. Man betracht die Benutzungen von Bestimmten Fungiziden so gut wie die konservierende Aktivitat den Anlagerungserzeugnissen in Gummigemenge. Los funglddas y los bacterlddas empleados para el caucho. Este artfcule se trata de los fungicidas y bactericidas empleades anterionnente y actualmente para proteger el caucho centra el deterioro microbiano. Se da Ia atenci6n a las ventajas de ciertos fungicidas tante como a Ia acci6n fungicida de aditivos inclufdes en mezclas de caucho.

for a deteriorated material, as well as requirements pointed out by Dolezel (1964) and MacLachlan et a/. (1966) an ideal fungicide or bactericide for rubber must meet following requirements:

I. Good compatibility and mixing properties with the rubber mixture

2. Chemical inertness to other components of the rubber mixture

3. No influence on the physical, chemical and mechan-ical properties of the final rubber product

4. Low volatility and good heat-stability

5. Resistance to leaching by water

6. Easy incorporation in the manufacturing process

7. Non-toxic or at least non-hazardocs to the workers in the rubber factory

8. Non-hazardous in the final rubber products

9. Durable during storing and for the service life of the product

10. Non-<:orrosive to metals

II. Price justifing the economical effectiveness.

As may be seen the requirements for fungicides are high and it may be concluded that up to date an ideal compound, which would fulfill all these requirements, has not been found. Every compound used as a fungicide has advantages and disadvantages. For this reason the choice of a fungicide for a given type of rubber has to be very careful.

3. List of fungicides and bactericides for rubber

Summing up the available papers on the subject of protecting rubber against microbiological deterioration for the period of the last 30 years the list of fungicides is given. Having in view the chemical characteristics of those compounds, they can be divided into seven following groups:

'Central Mining Institute, Katowice, Plac Gwark6w I, Poland. Translated into English by Dr. B. J. Zyska.

3

Fungicides and bactericides for use in rubber. Bozena J. Rytych.

1. Phenol derivatives

o-nitrophenol (Borecki et a/., 1965). p-nitrophenol (Yohe, 1939; Heinisch, 1962; Borecki

eta/., 1965; Blahnik and Zanova, 1965). dinitrophenol (Kost et a/., 1959). p-chlorophenol (Y ohe, 1939). tetrachlorophenol (Dolezel, 1964). pentachlorophenol (Y ohe, 1939; Ritzinger, 1959;

Reinsch, 1962; Dolezel, 1964; Blahnik and Zanova, 1965).

pentachlorophenyl laurate (National Coal Board, 1953; Angus, 1954; Catomance, 1954; Anon., 1960).

p-chloro-m-cresol (Borecki et a/., 1965). o,pbenyl phenol (Dunlop Rubber Co., 1954; Kost

et a/., 1959; Brown, 1959 1960; Rajevski and Slogov, 1964).

dihydroxydichlorodiphenyl methane and its sodium salt (Dunlop Rubber Co., 1950a; 1950b; Blahnik and Zanova, 1965; Bakanauskas and Prince, 1955; Heinisch, 1962; Leeflang, 1963; Dolezel, 1964; Borecki et a/., 1965).

3-alkyl"2,2' -dihydroxy-3,5,5', 6' -tetrachlorodiphenyl methane (Dow Chemical Co., 1950).

o-phenylphenoxide (Heinisch, 1962). tetrachlorothymol (Kost et a/., 1959; Blahnik and

Zanova, 1965).

2. Sulphur compounds

thiuram derivatives: tetramethylthiuram monosulphide (Du Pont 1952). tetramethylthiuram disulphide (Dimond and Hors­fall, 1943; Blahnik and Zanova, 1965; Cousins eta/., 1957).

salts of dithiocarbamic acid: zinc diethyldithiocarbamate (Yeager, 1954; Dolezel,

1964; Blahnik and Zanova, 1965). zinc dibutyldithiocarbamate (Blahnik and Zanova,

1965). lead dimethyldithiocarbamate (Blahnik and Zanova,

1965). sodium dibutyldithiocarbamate (Blahnik and Zanova,

1965). copper dimethyldithiocarbamate (Fajfer and Jirsa!,

1959; Blahnik and Zanova, 1965). esters of dithocarbamic acid (Societe des Usines

Chimiques Rhone- Poulene, 1950) mixtures of mentioned salts of dithiocarbamic acid

(Bakanauskas and Prince, 1955). mercapto benzothiazole and its derivatives: 2-mercapto benzothiazole (Dimon and Horsfall, 1943;

Dolezel, 1964; Blahnik and Zanova, 1965). zinc mercapto benzothiazole (Blahnik and Zanova,

1965). sodium mercapto benzothiazole (Vanderbilt Co., 1952) halogen derivatives of mercapto benzothiazole and

their salts (Monsanto Chemical Co., 1958). benzothiazole disulphide (Dolezel, 1964; Blahnik and

Zanova, 1965). mixture of benzothiazole disulphide and copper-8-

quinolinolate (Monsanto Chemical Co., 1952). thiothiazyl ethers (Goodrich Co., 1953).

4

3. Salicyl acid derivatives

salicylanilide (Yohe, 1939; Brit. Cott. Ind. Res. Assoc., 1940; Farben Fab. Bayer, 1961; Heinisch, 1962; Dolezel, 1964; Rajewski and Slogova, 1964; Glupushkin eta/., 1966).

sodium salt of salicylicortho-(or para-) toluidine (Brit. Cott. Ind. Res. Assoc.; 1940).

zinc salicylate (Lightbody et a/., 1954; Blahnik and Zanova, 1965).

salicyl o-anisidine (Brit. Cott. Ind. Res. Assoc., 1940).

4. Mercuric compouods

phenylmercuric bromide (Dolezel, 1964). phenylmercuric chloride (Yohe, 1939; Dolezel, 1964). phenylmercuric acetate (Dolezel, 1964). phenylmercuric borate (Dolezel, 1964). phenylmercuric salicylate (Dolezel, 1964). pyridymercuric stearate (Dolezel, 1964; Borecki eta/.,

1965). phenylmercuric o-benzosulphanilamide (Dolezel, 1964). mercuric-dodecyl"trimethylammonium phthalate (Dun­

lop Rubber Co., 1954). diary! mercury compounds (Sowa, 1952).

5. Naphthalene derivatives

copper naphthenate (Dunlop Rubber Co., 1954; Dolezel, 1964).

zinc naphthenate (Dolezel, 1964). tetrabrombeta naphthol (Y ohe, 1939).

6. Quinoline derivatives

8-hydroxyquinoline (Wren, 1964). copper-8-quinolinolate (Phillips Brit.P.988484; Mon-

santo Chern. Co., 1952; Bakanauskas and Prince, 1955, Ritzinger, 1959; Dolezel, 1964; Rajewski and Slogova, 1964, Ross, 1964; Hueck van der Plas, 1966).

zinc-8-hydroxyquinolinolate (Dolezel, 1964).

7. Miscellaneous fungicides

zinc benzoate (Blahnik and Zanova, 1965). cyanides (Blahnik and Zanova, 1965). beta-dithiocarbazyl carboxylic' acid (Goodrich Co.,

1953). di-o-toluene-quanidine (Lightbody eta/., 1954; Blahnik

and Zanova, 1965). 10 (2-mercaptobenzothiazolylthil)-5, 1~dihydrophen­

narsazine (Biro and Parkany, 1963). 1-methyl-2-phenyl-3-dodecylbenzimidazolium bromide

(Farben Fabr.Bayer, 1966). 3,4-dichlorobenzyldimethyldodecylammonium chlor-

ide (Farben Fabr.Bayer, 1966). stabilised resin amines (Hercules Powder Co., 1952). tallium carbonate (Yohe, 1939). tributyl tin derivatives (Hueck van der Plas, 1966).

Fungicides and bactericides for use in rubber. Bozena J. Rytych.

4. The classic fungicides

According to the frequency of quotation of fungi­cides for rubber in literature it can be seen that only a few compounds have found a wide use. These are compounds known for a longer period and among these the following may be listed: nitrophenol; pentachloro­nitrophenol; dihydroxydichlorodiphenyl methane; o­phenylphenol; salicylanilide and copper-8-quino lino­late.

5. More recent fungicides

It must be admitted, that the total knowledge on the protection of rubber products against microbiological deterioration is still very small. The most frequent publications in this subject are found in English or American technical literature, but often they do not put forward any new ideas on the fungicidal properties of the compounds. Among the fungicides proposed in recent years by British firms the following should be mentioned: halogen derivatives ofmercapto-benzothia­zol and their salts, according to Brit.Pat.873 602 (1958); o-phenylphenol for rubber items used in dairy equip­ment, according to Brit. Pat. 883 448 (1959); mixture of salicylanilide with hydroxydiphenyl methane or dihydroxydiphenyl methane or dihydroxydiphenyl sulphide, according to Brit. Pat. 916 539 (1961); and concentrates of 8-hydroxyquinoline for rubber latex to protect against deterioration by bacteria, according to Brit. Pat. 949 364 (1964). Investigations of Winner (1957) indicate the usefulness of lauric acid to protect rubber against bacteria. Dubrovin (1959) sees the possibility of use ofazomethine derivatives of thiophene and Hofmann (1962) advises the use of Antimykotikum produced by Bayer.

Although information on the accelerating influence of copper salts on the ageing of rubber has been known for a long time, the copper compounds are still recommended as useful fungicides. Ritzinger (1959) advises the use of Ottacide P and Milmer I, which are copper•8,quinolinolate, for protecting neoprene. Barnes (1964) recommends the use of copper naph­thenate to protect insulating materials. Glupushkin et al. (1966) recommend, apart from salicylanilide, Albichtol, which is a mixture of thiophene with hydro­carbons not exactly identified, in rubber mixtures for electrical cables in tropical climates. The paper of Hoeck van der Plas (1966) gives the most recent information of fungicides for rubber. These fungicides are for sale in West European markets. It may be seen from this list, that the choice of compounds is very small. It is surprising that copper or mercury com­pounds are still marketed. A novelty is the recommen­dation of captan and folpet to protect rubber.

6. Advantages and disadvantages of certain fungicides

Knowledge of the advantages and disadvantages of various fungicides for rubber is at the moment in­sufliciont but some information is available and may be reviewed.

5

Phenylmercury compounds are used in greater quantities in Czechoslovakia and have the reputation of effective fungicides for rubber. Apart from phenyl­mercuric acetate they are insolubJe in water, but easily soluble in organic solvents. Their disadvantage is that they are poisonous to human beings and corrosive to aluminium, lead and selenium. Dolezel (1964) states that this group of compounds lose their fungicidal activity after a time. Salicylanilide should not be used for the protection of rubber insulations since it absorbs moisture, resulting in decreased insulating properties of cables, however it may be recommended for other rubber products (Glupushkin, 1966).

The need to protect rubber-coated fabrics also involves the problem of investigating the influence of fungicides for cotton on the physical and chemical properties of rubber as well as on the adhesion, abrasion and strength properties of the rubber-coated product. These investigations were undertaken by Stief and Boyle (1947). The fungicides tested were: copper naphthenate; pyridylmerc11_ric stearate; sali­cylanilide; pentachlorophenol and 2,2'-methylbis(4-chlorophenol). The influence of these fungicides was investigated in natural rubber, GR-S and neoprene. In aged natural rubber copper naphthenate caused rapid deterioration. Other fungicides had no influence on natural rubber. In GR-S copper naphthenate caused a remarkable loss of strength. Pyridylmercuric stearate had a slight negative effect while the other fungicides had no effect on the physical properties of GR-S. In the case of neoprene copper naphthenate caused a loss of tensile strength after ageing but on the other hand an increase in elongation and tearing strength, Similar tests were done by Hum and Leggett (1947) but here, as well as copper naphthenate, the influence of lubricating oil on six types of rubber was also evaluated. The ageing showed no effect on the rubber when oil was not present. When oil was added to the fabric the copper accelerated the deterioration only when the oil itself negatively affected the rubber.

The question of leachability of fungicides from rubber products is still not satisfactorily explained due to contradictory information. In the opinion of Leeflang (1963) the solubility of fungicides is necessary to enable the fungicidal action, but in this case there is danger of leaching out. For this reason soluble fungicides do not give durable protection of rubber and from this point of view the following fungicides have been tested and disqualified: dichlorophene (up to 3 per cent), p•dichlorobenzene (Chlobol) up to 3 per cent; Termittenschutzmittel P 22 (composition unknown): KA 7007 (a mixture of phenols and sulphur compounds): dichlorophene (Preventol G-D); fungicide on glycol basis '(composition unknown), thymol up to 2 per cent; Arquad 18 up to 4 per cent. In the opinion of the National Coal Board (1953), which used copper naphthenate and pentachloro­phenyl Iaurate to protect rubber coated hoses these two compounds have proved unleachable.

A very interesting problem not often mentioned in the literature is the synergism of mixtures offungicides

Fungicides and bactericides for use in rubber. Bozena J. Rytych.

for rubber. It was R. T. Vanderbilt Co. Inc. (1952), who pointed out the synergic action of sodium salt of mercaptobenzothiazol and dimethyldithiocarbamate in Vanicide 51. Yeager (1954), basing on his own investigations, gives as an example the synergism of zinc dimethyldithiocarbamate and zinc 2-mercapto­benzothiazol. The synergic mixture given by Bakanaus­kas and Prince (1955) is close to those explained by Yeager. Here it is a mixture of zinc salts of dimethyl­dithiocarbamic acid with mercaptobenzothiazol and dehydroabietylammonium pentachlorophenoxide. It frequently occurs that fungicides lose their fungicidal effect when introducted into a given type of rubber. Also the effect of the environment in which the rubber will be used must be considered, but more investiga­tions are necessary. An extensive series of tests done by Kost et a/. (1959) on the influence of phenolic derivatives on micro-organisms isolated from rubber is of no significance as the toxicity of the compounds was tested on tissue-paper. In this way the inhibiting influence on the cellulolytic activity of these compounds was evaluated, but not their suitability for protecting rubber against microorganisms. According to the information given by Stief and Boyle (1947) and Hum and Leggett (1947 )a fungicide suitable for one type of rubber is useless in another type of rubber.

U.S. Patent 2608551 (1949) gives the information that butadiene-acrylonitrile vulcanisate may have fungistatic properties when 100 parts by weight of the elastomer are heated with 1·5 part of dithiobis­benzothiazole, 1·5 parts of sulphur and 3 ·44 parts of copper 8-quinolinolate. This method of obtaining fungistatic vulcanisate is not recommended for use in natural rubber but can be used with GR-S, neoprene and Thiokol rubbers. Similar was an earlier opinion of Phillips (1947), who found that copper 8-quinolino­late controlled well the growth of fungi in Perbunan 26, Hycar OR-15 and Thiokol rubbers, but supported the fungus growth in natural rubber mixtures. Dolezel (1964) discussing the protection of natural rubber, chloroprene and buna S against microbiological deterioration recommends the following fungicides: pyridylmercuric stearate; salicylanilide; pentachloro­phenol; dehydroabietylammonium pentachlorophen­oxide and 2,2' -dichloro-5,5'-dichlorodiphenyl methane.

7. Fungicidal action of additives in rubber mixtures The additives in rubber mixtures may influence the

susceptibility of a finished rubber product to micro­biological deterioration either in a positive or a negative sense. From this point of view this paper presents only a review of additives which are able to give fungistatic or fungicidal properties to the rubber product. According to Blahnik (1965) there are few investigations into the fungicidal or fungistatic effectiveness of the additives to be bound with rubber in finished products.

Accelerators for rubber Dimond and Horsfall (1943) were the first to test

the fungicidal properties of such accelerators as 2-mercaptobenzothiazole and tetramethylthiuram di­sulphide. They found that the first compound had

6

average properties and the second excellent. According to Rook (1955) neither 2-mercaptobenzothiazole nor tetramethylthiuram disulphide, when added as accel­erators to the rubber mixture in a normal amount protects rubber against micro-organisms. On the other hand high amounts of tetramethylthiuram disulphide may negatively influence the final properties of rubber, although in the opinion of Bieri (1959) it protects butyl rubber against moulds. Basing on the investiga­tions of Yashin (1957), Blokh gives data from which it can be seen that tetramethylthiuram disulphide and 2-mercaptobenzothiazole lose their fungicidal effect when the rubber mixture is aged at 65°C for a period of 30 days.

In the Brit.P. 684 379 (1951) esters of dithiocarba­mate acid, used as accelerators, show bacteriostatic properties. Blehnik (1965) lists the following accelera­tors for rubber as having fungicidal properties: zinc dimethyldithiocarbamate; lead dibutyldithiocarbamate; sodium dibutyldithiocarbamate; mercaptobenzothiaz­ole and its zinc salt; benzothiazoldisulphide, tetra­methylthiuram disulphide and di-o-toluene-guanidine. Dubrovin et al. (1958) found that Zn, Sb, and Ni salts of salicylanilide, methylnaphthol, or methyl­diphenol act as accelerators in the rubber mixture, but additionally they protect the mixture against micro­organisms. Later investigations of Dubrovin (1959) have shown that several azometine derivatives of thiophene are good accelerators as well as fungicides for rubber. Good thermal resistance is an additional advantage of these compounds. They are: 5-methyl-2-thenyl-p-aminophenol; 5-methyl-2-thenylaminethanol and 2-thenyl-m-nitroaniline. The valuable properties of the above azometine derivatives are stated by Kuzminskii et a/. (1960) and are also mentioned by Blokh (1964).

Antioxidants As it is well known, several aromatic amines,

phenols as well as quinones are used in rubber mixtures for their improvement against the oxidation. When reviewing this group of compounds little information on their fungicidal properties is available. According to U.S. Patent 2 502 708 (1950) nitrated hydrogenated cardenol is claimed to be an antioxidant having some fungicidal properties. Winner (1957) was perhaps the only investigator who tested the bacterial properties of some antioxidants for rubber. On the other hand Blahnik (1965) doubts whether the small amount of antioxidants used in the finished product are able to protect the rubber against micro-organisms.

8. Conclusion In the past years a great effort has been made to

select fungicides and bactericides for natural and synthetic rubber. The problem is not yet satisfactorily solved and several questions have to be explained and investigated. It seems that there is a need for investiga­tion into the mechanism of the deterioration of rubber by micro-organisms, the choice of fungicides for a given type of rubber, the synergism of fungicides for rubber, and into the fungicidal properties of several additives, used in rubber mixtures.

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Fungicides and bactericides for use in rubber. Bozena.J. Rytchy.

References

Angus, G., Co. Ltd. (1954). Brit. P. 734 245. Fire hose.

Anon. (1960). Ets. Vhevassus. Note Technique, No. 174 (4): Antifungus protection of plasticizers and rubber stocks with "Randon" based on Iaury! pentachloro­phenol.

Bakanauskas, S. and Prince, A. E. (1955). Appl. Microbiol. 3, 86-87. Requirements for fungicides in selected Air Force Materials.

Barnes, C. C. (1964). Electric cables. London, Sir Isacc Pitman and Sons Ltd.

Bieri, B. (1959). Schw. Archv. 25, (6), 210-16. Mould resistance of insulants on electrical conductors.

Biro, J. and Parkany, M. (1963). C.A. 58, (7), 7009. Vulcanization accelerator with a strong fungicide effect.

Blahnik, P. and Zanova, B. (1965). Mikrobiologiches­kaya korroziya. Moskva, Izd.Khimiya.

Blake, J. T.; Kitchin, D. W. and Pratt, O.S. (1950). Elec. Eng. 69, 872-93. Failures of rubber insulation caused by soil micro-organisms.

Blake, J. T. and Kitchin, D. W. (1949). Ind. Eng. Chern. 41, 1633-41. Effect of soil micro-organisms on rubber insulation.

Blake, J. T.; Kitchin, D. W. and Pratt, 0. S. (1953). A.I.E.E. Trans. 72, 321-8. The microbiological deterioration of rubber insulation.

Blake, J. T.; Kitchin, D. W. and Pratt, 0. S. (1955). Appl. Microbiol. 3, (!), 35-39. The microbiological deterioration of rubber insulation.

Blokh, G. A. (1964). Organicheskie uskoriteli wulkani­zatsii kauchukov. Moskva. Izd. Khimiya.

Borecki, Z; Czerwh\ska, E.; Eckstein, Z. and Kowalik, R. (1965). Chemiczne !rodki grzybobCjcze. (Fungicides). Warszawa. Pat\stwowe Wydawnictwo Rolnicze i Le!ne.

British Cotton Industry Research Association (1940). Brit. P. 323 579. Mildew-proofing of textile materials etc.

Brown, D. S., Co. (1959). Brit. P. 883 448. Microbicidal elastomer articles.

Brown, D. S., Co. (1960). U.S. Patent 2 947 282. Microbicidal elastomer articles.

Calderon, 0. H. and Staffeld!, E. E. (1965). Int. Biodetn Bull. 1, (2), 33-36. Colonization of silicone rubber by micro-organisms.

Catomance Ltd. (1954). Electr. J. 150, 1521. Laury! pentachlorophenol.

Cousins, Ch.M.; Clegg, L. F. L.; Thiel, C. C.; Akam, D. N.; Jones, G. E. and Egdell, J. W. (1957). J. appl. Bact. 20, I, 158-166. Studies on the use of bactericidal rubber in milking machine clusters.

Dimond A. E. and Horsfall, I. I. (1943). Rubber Age, N.Y. S3, 242-3, Preventing the bacterial oxidation of rubber.

Dolezel, B. (1964). Korroziya plasticheskikh materialov i rezin. Moskva, Izd. Khimiya.

7

Dow Chemical Co. (1950) Brit. P. 676 859. 3-alkyl-2, 2' -dihydroxy-3,5,5'6' -tetra-chlorodiphenyl methanes.

Dubrovin, G. I.; Invanova, S. N.; Mielnikov, N. N.; Yashish, V. B. and Glupushkin, P. M. (1958). C.A. 52, (21), 19228. Vulcanization of rubber mixtures.

Dubrovin, G. I. (1959). Zh. Prikl. Khirn. 32, (11), 2547-50. Biologicheskoe starene kabelnoi reziny.

Dunlop Rubber Co. Ltd. (1950). Brit. P. 663 273. Composite products of rubber and textile material.

Dunlop Rubber Co. Ltd. (1950). Brit. P. 675 200. Articles having an improved resistance to microbial attack.

Dunlop Rubber Co. Ltd. (1954). Brit. P. 685 614. Quaternary ammonium salts and articles containing them.

Dunlop Rubber Co. Ltd. (1954). Brit. P. 750 513. Composite products of natural or synthetic rubber and textile material.

Du Pont, E. I. de Nemours Co., Inc. (1952). Low brittle point neoprene compounds that are fungus resistant. Wilmington. Del. Rept. Bl.-247.

Erikson, D. (1941). J. Bact. 41, 277, in Blahnik, P. and Zanova, B. (1965). Mikrobiologicheskaya korroziya. Moskva, Izd. Khimiya.

Fajfer, M. and Jirsak, K. (1959). Czechosl. P. 92 727. Methods ofimproving the heat resistance and fungus resistance of vulcanizates.

Farbenfabriken Bayer AG. (1961). Brit. P. 916 539. Imparting anti-microbial properties to rubber and rubber articles.

Farbenfabriken Bayer AG. (1966). Chern. Zentrallblatt, 137, (24), 8180. Pilzschutzmittel fiir Kautschuk u. Artikel.

Glupushkin, P.M.; Saakyan, A. E. and Shcherbakov, D. P. (1966). Kabelnye reziny. Moskva, Leningrad, Izd. Energiya.

Goodrich, B. F., Co. (1952). U.S. Patent 2 485 330. Fungicidal compositions.

Goodrich, B. F., Co. (1953). U.S. Patent 2' 623 059. Beta-dithio-carbazylcarboxylic acid compounds.

Gray, P. H. and Thornton, H. G. (1928). Z. Bakteriol. II. 73, 74, in Blahnik, P. and Zanova, B. (1965). Mikrobiologicheskaya korroziya. Moskva, Izd. Khimiya.

Greathouse, G. A. and Wessel, C. I. (1954). Deteriora­tion of materials. New York, Reinhold Pub!. Co.

. Harvel Corp. (1950). U.S. Patent 2 502 708. Cardenols.

Heinisch, K. F. (1962). Rubber Res. Inst., Ceylon, _38, 3/4, 40.46, Preservation of sheet rubber agamst mould. Part 2. Mould growth on smoked sheet.

Hercules Powder Co. (1952). U.S. Patent 2 492 939. Complex salts of stabilized rosin amine.

Hofmann, W. (1962). Kautsch. u. Gurnrni 15, (12). WT 501-2, 505: Anti-microbial rubber articles.

Hueck van der Plas, E. H. (1965). Int. Biodetn Bull. 1, (1), 1-7, Cooperative research in biodeterioration.

Fungicides and bactericides for use in rubber. Bozena J. Rytych.

Hueck van der Plas, E. H. (1966). Int. Biodetn Bull. 2, (2), 69-120, Survey of commercial products used to protect materials against biological deterioration.

Hum, I. K. Y. and Leggett, M. B. (1947). Bib!. Sci. Ind. Reports 5, 853, Effect of copper naphthenate in fabrics on the ageing of rubber.

Kalinenko, B. 0. (1938). Mikrobio/ogiya, 7, !19-28, Rol plesnevikh gribov, aktinomycetov i bakterii v razrushenii kauchukov.

Kost, A. N.; Nette, I. T. and Pomorsteva, N. W. (1959). Vestnik Moskovskogo Universiteta, 14, (3), 213-20, Deistvie fenolov na mikroogranizmy raz-rushayushchiye kauchuk i reziny. ·

Kuzmit\skii, A. S.; Goldfarb, J. L.; Fiedorov, B. P.; Zanchenko, A. I.; Kogerman, A. P. and Gorushkina, G. I. (1960). Z. Prikl. Khim. 33, (5), 1182-!187, Sintez nekotorykh proizvodnikh tiofena i znachenie ikh powiedlenya w kachestve ingedientov rezin (uskoritelei i antioksindantov).

Leeflang, K. W. H. (1963). J. Amer. Water Works Assoc. 55, (12), 1523-35, Microbiologic degradation of rubber.

Lightbody, A.; Robests, M. E. and Wessel, I. (1954). Rubber and plastics in deterioration of materials. New York, Reinhold Pub!. Corp.

MacLachlen, I.; Heap, M. and Pacitti, J. (1966). Attack of bacteria and fungi on rubbers and plastics in the tropics. In Micro-biological deterioration in the tropics, S.C. I. Monograph No. 23, Butler, N. I. and Eggins, H. 0. W. [Eds.], London, Society of Chemical Industry.

Monsanto Chemical Co. (1952). U.S. Patent2 608 551. Fungistatic copolymers of 1,3-butadiene and organic nitrites.

Monsanto Chemical Co. Ltd. (1958). Brit. P. 873 602. Mycobacteriostatic compositions.

Morris, Leslie Ewart (1927). J. Textile Inst. 18, T99-T127, In Greathouse, G. A. and Wessel, C. I. (1954). Deterioration of materials. New York, Reinhold Pub!. Co.

National Coal Board, Production Depart. (1953). Inf Bull. 53/87, London. Care and maintenance of canvas hose.

Nette, I. T.; Pomorceva, N. W. and Kozlova, C. I. (1959). Mikrobiologiya 28, (6), 881-886, Razrusheniye kautshuka mikrorganozmami.

Phillips, L. C. Brit. P. 98 848. Investigation of fungi­static and curative properties of copper 8-quinolino­Iates in synthetic and natural rubbers.

Raevskii, W. G. and Slogova, L. P. (1965). C.A. 63, · (10), 13470, Effect of fiber impregnation against mildew on some properties of rubber coated fabrics.

Ritzinger, G. B. (1959). Ruhh. Plast. 40, (10), 1067-1069, Fungus resistance of neoprene and effect compounding and use of fungicides.

8

Rook, J. J. (1955). Appl. Microbial. 3, 302-9, Micro~ biological deterioration of vulcanized rubber.

Ross, S. H. (1964). Environmental effects on materials and equipment, 4A (2), 88. Fungus resistance of silicone potted firings modules.

Schulze, B. (1939). Holz als Roh-und Werkstoff 2, 99~109, Umfassen-de Priifung von Holzschutzmittel gegen holzzerstiirende Pilze und Tiere.

Scott, I. (1920),/.R.l. 60,410-412, Rubber micro fungus.

Societe Des Usines Chimiques Rhone-Poulene (1951). Brit. P. 684 379, Esters of dithiocarbamic acid.

Societe Des Usines Chimiques Rhone-Poulene (1950). Brit. P. 690 061. Protecting articles against fungal and mould growth.

Sohngen, N. and Foil, G. (1914). Zbl. Bakt. ll Abt. 40, 87. Decomposition of rubber by microorganisms.

Sowa, F. I. (1952). Brit. P. 605 442, Diarylmercury compounds.

Spence, D. and Van Niel, C. B. (1936).lnd. Eng. Chern. 28, 847-50. Bacterial decomposition of the rubber in Hevea latex.

Stief, G. L. and Boyle, I. I. (1947). Ind. Eng. Chem. 39, !136-8, Effect of fungicides on rubber.

Shaposhnikov, W. N.; Rabotnova, I. P.; Jarmola, G. A.; Kuzniecova, W. M. and Masokhina, N. N. (1952). Mikrobiologiya 21, (2), 146-154. 0 razvitii bakterii za schet naturalnogo kauchuka.

Shaposhnikov, W. N.; Rabotnova, I. P.; Jarmola, G. A. and Kuzniecova, W. M. (1952). Mikrobiolo­giya, 21, (3), 280-282, 0 razwitii plesnevykh gribov za schet naturalnogo kauchuka.

Taysum, D. H. (1966). S.C.!. Monograph No. 23, 105-120, Butler, N. I. and Eggins, H. 0. W., [Eds.], London, Society of Chemical Industry.

Vanderbilt, R. T. & Co. Inc, (1952). Vanderbilt News 18, (6), 10-!1, Vanicides 51 and 51 z.

Wessel, C. I. and Bejuki, W. M. (1959). Ind. Eng. Chern. 51, (4), 52A-63A, Industrial fungicides.

Winner, H. I. (1957). J. Appl. Bact. 20, 88-9, Note on the anti-bacterial effect of processed natural rubber. In C.A. 51, 21, 16682, 1957.

Wren, W. G. (1964). Brit. P. 949 364. Rubber latex preservation from bacterial attack.

Yeager, C. C. (1954). Canad. Chern. Process. 38, (7), 58-9, Improvement in fungicides through formula­tions.

Yo he, R. V. (1939). Products, April, Preventing mildew on rubber products.

ZoBell, C. E. and Grant, C. W. (1942). Science 96, 379-380, The bacterial oxidation on rubber.

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I I

Hoffmann, E. Int. Biodetn Bull., 5, (1), ,(1969). Assessment of paints for fungus resistance.

ASSESSMENT OF PAINTS FOR FUNGUS RESISTANCE E. Hoffmann'

Summary. The testing of fungus~resistant paints is described and discussed.

Evaluation des peintures risistant 3 l'attaque par Jes champignons Description et discussion des peintures rtsistant a l'attaque par les champignons.

Cases of mould growth on painted surfaces occur under a wide range of climatic conditions throughout Australia, from the tropical humid areas in the north to the temperate regions in the south. This leads to considerable expense in redecoration, and it is there­fore important to ensure that coatings used in areas susceptible to the growth of mould have a high degree of fungus resistance. • ·

Two methods are at present in use for evaluating compounds claimed to increase the fungus resistance of paint. The first is the Vicklund-Manowitz (V.M.) test or one of its numerous modifications. Mter many years of comparing the assessments of these laboratory tests with actual performance in the field, most workers are now convinced that no correlation exists. The method is valuable in showing whether a compound is active as a fungicide or has some effect in inhibiting fungus growth, but even then some care is required since some paint compositions which do not show fungus resistance in the V.M. test may exhibit it on exposure in the field (e.g. zinc oxide formulations).

lt is not surprising that this test fails to predict actual performance when it is considered that the conditions under which the testing is carried out are widely different from those prevailing in practice. Specifically the method does not take into account the loss of active ingredients which takes place in the field. Some workers have tried to correct this by exposing the paint films to artificial weathering before carrying out the test, but correlation between artificial and natural weathering is usually so poor that scarcely anything is gained by introducing this step.

The second method used is to expose test panels at sites where mould growth occurs, and recommenda­tions for fungicides in paint are largely based on the outcome of these tests. This is also a very unsatis­factory procedure, because in case of a failure it does not give any indication of why it occurs. For example, if a fungicide has been shown to be effective in the V.M. test but fails on exposure this could be due to loss of fungicide, to the presence of more viable or different types of mould to those which had been used, or to an

PrUfung der Pilzwiderstandsfiihigkeit l·on Farben. Die PrUfung pilzbestiindiger Farben wird beschrieben und erUiutcrt.

Avaluaci6n de las pinturas para Ia reslstencia a los bongos. Se describe y se discute las maneras de probar las pinturas resis­tentes a los bongos.

exceptionally heavy deposition of plant material. The latter is common with gloss latex paint films, which are especially prone to retain matter blown on to them (Hoffman, 1967).

It is clear that if fungicides are to be used in a rational way, it is desirable to determine the stability of these compounds in paint formulations and under the conditions in which the paint will be used. For this reason it was proposed some years ago (Hoffmann and Georgoussis, 1960; Hoffmann 1963) to combine bio-assay techniques with chemical analysis and to investigate systematically the stability of fungicides in paint films. Such a study has been made for phenyl­mercury compounds (Hoffmann and· Georgoussis, 1960; Hoffmann and Bursztyn, 1963, 1964; Hoffmann, Saracz, and Bamed, 1966b; Hoffmann, 1964), penta­chlorophenol (Hoffmann, Saracz, and Barned, 1966a), para toluene sulphonamide (Hoffmann, Saracz, and Bamed, 1967), zinc oxide (Hoffmann et a/., 1968), tetramethyl thiuram disulphide (Hoffmann and Saracz, 1969a), salicylanilide, barium metaborate, N-trichloro­methylthio-phthalimide (Hoffmann and Saracz, 1967), and copper hydroxyquinolate. The paints are bmshed out on sheets of polyethylene terephthalate polyester film, which are then usually exposed under the following conditions:

(1) Outdoors at Highet!, Victoria (2) In a fog room at 20'C (3) In a constant temperature room at 20'C and

65 per cent R.H. (4) In a hot room at 38'C, 30 per cent R.H. (5) Outdoors at Lae, New Guinea

At Lae, New Guinea, panels of asbestos cement painted with the same coatings are also exposed, and the mould growth is assessed at intervals.

Results obtained under these exposure conditions give a good indication of the fungicidal or fungistatic value of the compound under investigation, that is, how long the fungicidal or fungistatic action is likely to persist, and under what conditions it should be used.

'Division of Building Research, Commonwealth Scientific and Industrial Research Organization, Melbourne, Australia. (Copy received December, 1968).

*It is difficult to give an exact figure for the damage caused by mould growth on painted surfaces, but an estimate can be made. Australia spends about S300 million per year on architectural paint and labour to apply it. From 5 to 10 per cent of this amount is spent in areas susceptible to the growth of mould, and an average improvement of 10 per cent in the lifetime of paint would therefore amount to SI.S to 3 million per year.

9

Assessment of paints for fungus resistance. E. Hoffmann.

Para toluene sulphonamide (PTSA) is recommended as a fungicidal additive to house paints for indoor and outdoor use. However, at Lae practically all the PTSA is lost from a paint film within six months, and panels coated with paint containing PTSA show no appre­ciable suppression of mould growth compared with the blanks. The loss of PTSA is also very high in the fog room but very low in the constant temperature room, and it can therefore be expected that this com­pound would be of value in situations where mould would grow at above 70 per cent R.H. but where conditions are not so bad that water is actually running down the painted surface, This has also been confirmed (Hoffmann, Saracz, and Bamed, 1967).

N•trichloromethylthio-phthalimide shows a com­paratively high stability in the fog room and at 20°C and 38°C, and is therefore likely to be of value in such places as bakeries, where temperature and humidity tend to be high.

The addition of zinc oxide to paints is claimed to increase their fungus resistance, and experiments with latex paints (Hoffmann eta/, 1968) showed that this is the case with some brands of zinc oxide. The increased mould resistance lasts only for about two years or less, and this could be ascribed to the adaptation of the mould to the presence of zinc oxide. Analysis of the layer of chalk on the paint film showed somewhat unexpectedly that the zinc oxide had been reduced to a very small percentage of what was originally present. For example, chalk which had been formed on a coating containing about 60 per cent zinc oxide by weight on its pigment content, was found on analysis to contain less than 5 per cent. The knowledge of this suggests an entirely different approach to the formula­tion of this type of fungus-resistant paint.

Copper hydroxyquinolate is more stable than the other fungicides tested so far, and panels coated with a paint containing it had very little mould on the upper side for three years but considerable mould growth was observed on the under side after six months. (The exposure racks at Lae slope at 45° and face 31 o east of true north, and the mould growth on both sides of each panel is being observed). N-trichloromethylthio­phthalimide is quite stable in paint films on the under side of the panels but less stable on the upper sides. The two fungicides were therefore combined in a coating to increase the mould resistance on the under side. After 15 months there is still very little growth of mould in this position.

Another approach in formulating a fungus-resistant paint with copper hydroxyquinolate suggests itself. The reason for the small activity on the under side of the panels could be that the paint film does not chalk sufficiently where it is not exposed to sunlight. Some decomposition of the copper hydroxyquinolate is likely to take place on the top layer of the film, but as this compound is not very soluble the loss cannot be replenished by diffusion, and hence the film becomes

less fungus-resistant. Sufficient chalking takes place on the top layer to expose enough copper hydroxy­quinolate to retain the fungus resistance. The activity of this fungicide may therefore be increased by formu­lating the paint so that it chalks slightly, and this could be done by replacing part of the rutile titanium dioxide with zinc oxide. To do this efficiently it is necessary to know quantitatively by how much the chalking is increased with given amounts of this pigment, and how this depends on the prevailing weather conditions. Work on this project, which is also important for a better understanding of the weathering process of paint films, is under way (Hoffmann and Saracz, 1969b).

It must be emphasised that a V.M. test combined with stability determinations does not replace a field test of the chosen formulation. For example, copper hydroxyquinolate shows up as active on the V.M. test and is also very stable, but in certain areas the paint containing it is not satisfactory. What the proposed approach • to testing of fungus-resistant paints allows is to choose from the very many possible paint formulations those that are likely to succeed in a given environment.

It has already been mentioned that panel exposures are a reasonable indication of the fungus resistance of paints that are to be used outdoors. Such a procedure is useless for coatings intended for indoor use. If painted panels are attached to walls on which mould growth is known to occur, it will often be found that the paint films show little or no mould, although the walls around the panels may be heavily infested. The reason for this is that less water vapour will condense on the panel, which is better insulated against heat loss than the wall. It follows that to test a paint for indoor use it must be applied directly to the surface which is to be decorated, and this should be done as shown in Fig. I. Three paints were applied to this wall (Saracz and Hoffmann, 1968)-A, a chlorinated rubber paint; B, a latex paint containing only rutile titanium dioxide as pigment; and C, a latex paint in which part of the titanium dioxide was replaced by zinc oxide. The figure shows the mould growth after four years, and it is evident that only the paint containing zinc oxide is effective.

It might be thought that it would be sufficient to divide the walls into three parts and to apply one type of paint to each part, but this could be very misleading, as can be seen from Fig. 2. The three paints A, B, and C were applied to the wall and its appearance after two years is shown in the figure. If paint B had been tested under two different names, believing them to apply to two different compositions, Bl and B2, it would have been concluded that Bl had a higher fungus resistance than B2, whereas in fact they have the same compositions. The difference is probably due to the slightly higher humidity at the wall surface which is under the sloping roof.

*The usefulness of the analytical method would in some cases be inCreased by following the Joss of the compound in question in the various layers of the paint films. This wou1d be of interest for fungicides which decompose very slowly, e.g. copper hydroxy­quinotate.

10

Assessment of paints for fungus resistance. E. Hoffmann.

Many workers still seem to believe that it is possible to develop a reliable accelerated laboratory test (other than the V.M. test) which will allow an assess­ment of the fungus resistance of paint. The author considers that this has little hope of success, because it is difficult to accelerate the loss of the mould­inhibiting compound of the paint in a realistic way. It has been suggested (O'Neill and Skinner, 1966) that painted specimens should be exposed in a weather­ometer for 250 hours and then tested for mould resist­ance in a cabinet which has recently been devised (Hendy, 1962). However, it is impossible to deduce from this how long the paint film will remain resistant to fungus, since nothing is disclosed about the rate of loss of the fungicidal compound.

The search for accelerated testing is understandable but must be futile unless a great deal is known about the mechanism of the change in properties to be measured. The stability of a fungicide is one of the most important features to he known in determining the fungus resistance of a paint film.

No detailed analytical procedure can be given, as this will vary with the compound to be analysed. However, two general principles have been followed: (I) The procedure must be quick, and (2) the apparatus used must be as simple as possible. Fungicides often contain elements such as mercury, chlorine, and sulphur which can be easily determined. An oxygen flask technique was used to obtain the element in a suitable form for analyses, and this was combined with an appropriate microchemical method to make a very quick estimation of the element in question.

It is sometimes necessary to modify known proce­dures, as is described, e.g. by Hoffmann and Saracz (1964). The equipment used in the combustion flask technique is shown in Fig. 3. A suitable absorbent, e.g. nitric acid for the determination of mercury, is added to the flask which is then filled with oxygen. A sample of paint film (50-100 mg) is wrapped in a paper carrier and placed in the platinum holder. The fuse is ignited and the platinum holder quickly inserted into the flask, after which the absorbent is analysed for the liberated element. With two of these flasks it is possible to make two determinations of mercury in one hour.

The combustion flask method was supplemented by extracting the fungicide from the paint film and determining its ultraviolet absorption spectrum. The techniques used in investigations for phenylmercury compounds (Hoffmann, 1964, 1965; Hoffmann and Saracz, 1964), pentachlorophenol (Hoffmann, Bursztyn and Saracz, 1965), N-trichloromethylthio-phthalimide (Hoffmann, Bursztyn, and Saracz, 1965), salicylanilide and para toluene sulphonamide (Hoffmann, Saracz, and Bursztyn, 1964), copper hydroxyquinolate (Hoff-

mann, 1966), and barium metaborate (Hoffmann, 1968) have been described and probably can serve as a model for similar cases.

Neglect to take into account the stability of fungici­dal compounds in paint formulations has given rise to contradictory opinions as to the effectiveness of these materials and a great deal of unnecessary work, and also to the production of inferior paints. The paint companies who are the users of fungicidal additives cannot be entirely blamed for this state of affairs. In the author's opinion the onus falls on the supplier to establish the stability of the compounds, and to develop and describe quick and simple analyti­cal techniques for their determination*. Paint com­panies should refuse to handle a product if these data are not supplied (Hoffmann and Saracz, 1967). A step in the right direction is exemplified by a recent advertisement in the Journal of the Oil and Colour Chemists' Association (Vol. 51 No.6 p.viii), in which the rate of decomposition of a phenylmercury com­pound (55 per cent lost in 4 months) is compared with the rate of Joss (90 per cent in 4 months) of phenylmercury dodecenyl succinate. This is important technical information, and the buyer knows what he is getting. It is then up to him to decide whether or not the improvement is significant for his purposes.

References

Hendy, N. I. (1962). Fungus and paint. J, Oil Colour Chem. Ass., 45, 343.

Hoffmann, E. (1963). The evaluation of fungicides. Aust. Paint J., 9(8), 11-16.

Hoffmann, E., (1964). Sulphide staining caused by phenylmercury compounds in paint. J. Oil Colour Clzem. Ass., 47, 581-583.

Hoffmann, E. (1965). Determination of phenylmercury compounds in fungicidal preparations and in paint. Z. analyt. C/remie, 214, 428-430.

Hoffmann, E. (1966). Analysis for fungicides in paint. IV. Determination of copper-S hydroxyquinolate. Z. analyt. Clzemie, 215, 101-104.

Hoffmann, E. (1967). A note on gloss latex paints. Aust. Paint J., 13(5), 13.

Hoffmann, E. (1968). Volumetric determination of barium metaborate in paint after extraction with mannitol solution. Z. analyt. Clzemie, 234, 354-356.

Hoffmann, E., and Bursztyn, B. (1963). Phenylmercury compounds as fungicides: Part II. J. Oil Colour Chem. Ass., 46, 460-466.

Hoffmann, E., and Bursztyn, B. (1964). Phenylmercury compounds as fungicdes: Part III. J. Oil Colour Clzem. Ass., 47, 871-877.

Hoffmann, E. and Georgoussis, 0. (1960). Phenyl­mercury compounds as fungicides. J. Oil Colour Clzem. Ass., 43, 779-786.

*It may be pertinent to illustrate what is meant by a simple technique. It has been proposed by TaYlor (1965) that the loss of mercury in paint films should be measured by a radioactive method. The method may be the simplest one for those who have facilities to prepare radioactive tagged compounds and the necessary equipment, but it certainly would not be a simple technique for a paint manufacturer's laboratory.

11

Assessment of paints for fungus resistance. E. Hoffmann.

Hoffmann, E., and Saracz, A. (1964). Determination of small amounts of mercury (0·01 to 10 mg). Z. analyt. Chernie., 199, 6-10.

Hoffmann, E., and Saracz, A. (1967). The formulation of fungus•resistant paints and fungicidal washes. J. Oil Colour Chern. Ass., 50, 425-440.

Hoffmann, E., and Saracz, A. (1969a). Formulation of fungus-resistant paints 4. Addition of tetramethyl thiuram disulphide. J. Oil Colour Chern. Ass. (in press).

Hoffmann, E., and Saracz, A. (1969b). Weathering of paint films 1. Chalking caused by zinc oxide in latex paints. J. Oil Colour Chern. Ass., 52, 113-132.

Hoffmann, E., Burszt:yn, B., and Saracz, A. (1965). Analysis for fungicides in paint. II. Determination of pentachlorophenol and N-(trichloromethylthio)­phthalimide. Z. analyt. Chernie, 207, 432-436.

Hoffmann, E., Saracz, A., and Bamed, J. R. (1966a). The formulation of fungus-resistant paints. I: Addition of pentachlorophenol. J. Oil Colour Chern. Ass., 49, 551-558.

Hoffmann, E., Saracz, A., and Bamed, J. R. (1966b). Phenylmercury compounds as fungicides: Part IV. J. Oil Colour Chern. Ass., 48, 631-638.

12

Hoffmann, E., Saracz, A., and Barned, J. R. (1967). Formulation of fungus-resistant paints: Addition of para toluene sulphonamide. J. Oil Colour Chern. Ass., 50, 516-523.

Hoffmann, E., Saracz, A., and Bursztyn, B. (1964). Analysis for fungicides in paint. III. Determination of salicylanilide and para-toluene sulphonamide. Z. analyt. Chernie, 208, 431-435.

Hoffmann, E., Lancucki, C. J., Moss, G., and Saracz, A. (1968). The formulation of fungus-resistant paints: Zinc oxide in latex paints. J. Oil Colour Chern. Ass., 51, 921-934.

O'Neill, L. A., and Skinner, C. E. (1966). Laboratory tests for resistance of paint films to mould growth under tropical conditions. Soc. Chern. Ind. Mono., 170-178.

Saracz, A., and Hoffmann, E. (1968). The evaluation of paint for fungus resistance. Zinc oxide latex paints. J. Oil Colour Chern. Ass., 51, 103-107.

Taylor, G. C. (1965). The loss of mercury from fungicidal paints. J. appl. Chern. Lond., 15, 232-236.

Assessment of paints for fungus resistance. E. Hoffmann.

Fig. I. Tests of fungicidal paints on the wall of a dye works.

Growth of mould in 4 years.

A-Chlorinated rubber paint

B-Latex paint pigmented with rutile titanium dioxide

C-Latex paint pigmented with rutile titanium dioxide and zinc oxide

13

Assessment of paints for fungus resistance. E. Hoffmann.

' . . --I . .

c Ba C A c

Fig. 2. Tests of fungicidal paints on the wall of a dye works. Growth of mould in 2 years. A-Chlorinated rubber paint

82 c

Bl & B2- Latex paint pigmented with rutile titanium dioxide C-Latex paint pigmented with ruti le titanium dioxide and zinc oxide.

Fig. 3. Oxygen combustion flask.

14

Walsh, J. H. and Stewart, C. S. Int. Biodetn Bull., 5, (!), 15-20, (1969). A simple method for the assay of the cellulolytic activitity of fungi.

A SIMPLE METHOD FOR THE ASSAY OF THE CELLULOLYTIC ACTIVITY OF FUNGI ,

J. H. Walsh' and C. S. Stewart•

Summary. A method for measuring the cellulolytic activity of fungi by the degree of clearing when the fungus is grown on a nutrient medium containing finely divided cellulose is described. This is estimated by measuring the area of the microscope field obscured by cellulose particles before and after fungal growth.

Une methode simple de contr6lc de l'actlvlte cellnlolytiquc des champignons. On decrit une methode de mesure de ractivit6 cellulolytique des champignons suivant le degre de clarification quand le champignon a poussC sur un milieu nourrissant con­tenant de Ia cellulose finement divis~. Cette clarification est 6valu6e en mesumnt Ia zone du champ microscopique obscurcie par les particules de cellulose, avant et apres Ia culture de champignons.

Introdnclion

Numerous methods have been used to measure the cellulolytic activity of fungi, and of these many have involved determinations of the diameters of cleared zones formed when fungi are grown on nutrient media containing finely divided cellulose.

A major problem enco)lntered in methods involving the study of clearing of cellulose is that fungal hyphae and spore clumps often obscure the clear zones. Two techniques have been used to overcome this problem. Aschan and Norkrans (1953) and Savory, Mather, Maitland and Selby (1967) incorporated growth inhibitors into the cellulose medium and inoculated this with borings from a healthy culture. Rautela and Cowling (1966) relied upon anaerobic conditions below the surface of a cellulose medium in test tubes to check fungal spread.

A consideration of these existing methods suggests to us that different criteria of cellulolytic activity are used according to whether the diameter of the cleared zone produced by a growing colony is measured or the width of the cleared zone around or under an inhibited colony. In the first case the measurement reflects the total cellulose destroyed per colony and this depends on the rate of colony spread, as well as on the activity of the cellulose degrading system. In the second case the activity of the cellulose degrading system is measured, and the effect of lateral spread largely excluded. To achieve this however the cleared zone which is measured is produced by cellulose enzymes working at a distance from the mycelium, so that factors such as the diffusibility and stability of the enzyme may be involved.

Ein elnfacbes Verfahren zur Prtlfung der cellulolytischen Aktivitlit von Pilzen. Ein Verfahren wird beschrieben, wn die celluloly­tische Aktivitiit von Pilzen durch den Grad der Aufhellung zu messen. Der Pilz wachst dabei auf einem N3.hrboden, der fein verteilte Cellulose enthiilt. Die cellulolytische Aktivitiit wird gemessen, indem man die FHiche des mikroskopischen Feldes misst, die von Celluloseteilchen und zwar vor und nach Pilz­bewuchs verdunkelt wird.

Un mCtodo sencillo de indagar Ia actividad celulolitica de los bongos. Se describe un metoda de medir Ia actividad celulolitica de los bongos segU.n el grado de aclaramiento cuando se cultiva el bongo en un media ambiente nutritive que contiene una celulosa dividida de manera menuda. Se tasa midiendo Ia extensi6n del campo microsc6pico obscurecido por las partfculas de celulosa antes y despues del crecimiento de los bongos.

The method proposed in this paper similarly attempts to measure the activity of the cellulose degrading system uninfluenced by lateral spread, but in an actively growing system. It does this by measuring the intensity of clearing, not the extent of the cleared zone, and the particles whose dissolution is measured are close under the colony, so that enzyme diffusion need take place over a microscopic distance, if at all. A further slight advantage of this method is that the large scale of measurement (0-90 units) may allow the separation of organisms of more nearly similar activity than is possible with existing clearing methods.

On theoretical grounds the results of the proposed clearing method should show a good correspondence to measurements of cellulolytic activity by tensile strength loss. Loss of tensile strength is determined by using an actively growing colony, but is relatively uninfluenced by lateral growth because only the strength of the weakest·point is measured. Standard tensile testers can also give a range of results over a scale from 0 to 100. In this paper therefore results by the proposed method have been compared to results by a standard loss of tensile strength technique.

Method

As a substrate, the nutrient medium of Eggins and Pugh (1962) was used, with incorporation of I% ball milled cellulose, as suggested by the authors. Two types of cellulose powder were studied. Firstly, 72 hour ball milled Whatman standard grade cellulose powder (CF 11) as suggested by the authors, and secondly a powder derived from a cotton yam which had proved on analysis to contain 10% non-cellulosic

1Department of Biochemistry, University of Manchester, Institute of Science and Technology, Sackville Street, Manchester I, England. 'Present address. Department of Microbiology, The Rowett Research Institute, Bucksbum, Aberdeen, AB2 9SB Scotland. (Copy received 31st October, 1968).

15

A simple method for the assay of the cellulolytic activity of fungi. J. H. Walsh and C. S. Stewart.

materials. To prepare this powder, the yarn was cut into small pieces ( = 1/8") and then hammer-milled to a fine floc. Finally the floc was ball milled in a Pascali Rotatory ball mill for 72 hours. Both types of powder consisted of irregular particles with an average diameter of about 3 f.l·

A 6 mi. aliquot of the nutrient medium, containing cellulose powder, was layered on top of 9 ml of water agar (1·2% Oxoid Agar No. 3 in dist. H,O) which had been allowed to solidify in a 10 em petri-dish. The top layer was added hot (about 70°C) and was swirled gently to ensure even coverage. At this temperature the cellulose particles settled to form a monolayer at the interface of the two agar layers before the upper agar layer solidified. The thickness of this monolayer did not exceed the depth of focus of the microscope used for particle counting.

Standard replicate inocula were obtained by using 6 m.m. borings taken from the same growth region of petri-dish cultures grown on Eggins and Pugh's cellulose medium. The dishes were incubated at 25°C, normally for 10 days.

Although it was possible in a few cases, (e.g. Chaetomium g/obosum) to make particle counts without removing the fungal growth, removal was normally necessary since dense surface growth obs­cured the cellulose particles. In these cases, sufficient growth was scraped off using a pair of flat-ended cover slip forceps in a gentle stream of water. Since the cellulose particles had settled to the bottom of the upper agar layer, any inadvertent damage did not alter the particle count.

The amount of clearing was estimated by counting the number of divisions of a linear micromete_r eye­piece (10 m.m. divided into 1/IOths of a m.m.) ap­parently occupied by cellulose particles immediately before inoculation with the test organism, and again after incubation. For counting, the plates were viewed through the reverse side, under a low power objective (total magnification 100 x). The 100 divisions of the eye piece micrometer corresponded to approximately 1·5 m.m. on the agar. Each division of the eyepiece was considered to be either 'occupied' or 'not occupied' by cellulose particles, and no attempt was made to count fractions of divisions covered. Since there were 100 divisions of the eyepiece, the figures obtained were essentially 'percentage cover' values, although the cover of the freshly prepared plate was only about 88-93%.

The area selected for counting was a zone about I em. in from the edge of the colony, and the micro­meter scale was set tangentially to the colony margin. Counts were made at two random points several centimetres apart within this zone, and in each case three replicate plates were studied.

Once hyphae have been scraped off, the plate is of no further use, so that if estimates are to be made after different periods, further replicates must be set up.

16

As a refinement, it was found that a sterile cover slip could be placed on top of the water agar layer before pouring the cellulose medium. For counting the cover slip and the nutrient medium were removed, inverted and placed on a glass slide, thus forming a mount of the cellulose agar with the particles upper­most directly beneath the cover slip. The advantage of this refinement was that a much clearer image was obtained when the particles were viewed under the microscope than with the usual method. Convenience apart however both methods gave the same results, and the results quoted in this paper were obtained with the original method.

Results

As a preliminary, counts were made on a large number of uninoculated plates in order to characterise the amount of variation which could be expected from the controls. A selection of representative counts obtained on uninoculated plates is shown in Table I together with estimates of standard deviation, each value quoted in the Table being the average of two counts. Since three replicate plates were later to be studied in the case of each organism tested, the control values shown in Table I are grouped into random triplets, as would normally occur upon inoculation of the plates.

TABLE !-Control values obtained before inoculation

(All values to nearest whole No.)

Average % Cover Triplet Plate Overall Standard

No. --------- Average Deviation I 2 3

I 86 87 91 88 2·6

2 88 89 89 89 0·7

3 89 90 91 90 1·0 ,

4 89 91 92 91 1·5

5 90 92 94 92 2·0

6 91 93 95 93 2·0

The results qnoted in Table I, together with most of the work quoted in this paper, were obtained using a cellulose powder derived from cotton yarn. This was done because we wished to compare estimates of cellulolytic activity obtained by the particle counting method with those obtained from measurements of tensile strength losses of cotton yarn. Due to the high level (approx. 10 %) of impurities present in the yarn, it was felt that such comparisons would be more valid if powdered yarn were used for the particle counting studies.

A simple method for the assay of the cellulolytic activity of fungi. J. H. Walsh and C. S. Stewart.

Since it is much easier to prepare ball milled cellulose from Whatman cellulose powder, tests were made to see to what extent this would give results similar to those for the powdered yarn. Since the particles are of the same size in each case, no modifica­tion of the method is needed, whichever powder is used.

Five organisms which showed rather sparse hypha! growth were selected for a comparison of the utilisation of ball milled Whatman cellulose powder (CF II) and

cotton yam powder. In these cases, successive deter­minations of particle counts could be made on the same plates after various time intervals, since it was not necessary to remove the fungal growth before counting. The results obtained with two of the fungi studied, Trichoderma koningi and an unidentified Aspergillus sp., are shown in Fig. I. The percentage clearing after 10 days for all five organisms studied is listed in Table 2.

Figure 1 Comparison of utilisation of ball milled Whatman cellulose powder CF 11, and cotton yarn powder. Incubation at 25°C.

TRICHODERMA KON.• T. ASPERGILLUS SP. 9. =A.

t- 75 z

z 8 uso

0

I

/

1: / ,/T

/ I

I

' I

--1

-,,·1 .... ' .... '

:t~/ A ,-'""" A.-..:-------A - ... -. ----3 7 10

TIME IN DAYS. -·- COTION YARN POWDER. --··-- BALL MILLEDWHATMAN

CF.II.

17

A simple method for the assay of the cellulolytic activity of fungi. J. H. Walsh and C. S. Stewart.

TABLE 2--Comparison of utilisation of Whatman cellulose powder and cotton yam powder; % clearing after 10 days at 25°C.

Initial % Organism cover, before

inoculation

Aspergillus sp. No. 9 93

Chaetomium g/obosum 90

Fusarium moniliforme 91

Gliomastix sp. 95

Trichoderma koningi 90

From these results, it can be seen that the attack of cotton yarn powder is higher throughout, although by an inconsistent margin. The results obtained were similar however, in that when fungi were arranged in sequence of their cellulolytic activity, .the same order was obtained, regardless of which powder was used for the assay.

The cellulolytic activity of a large number of fungal isolates was then measured by the particle counting method, using yarn cellulose powder. Simultaneously, the cellulolytic activity was estimated by the decrease in tensile strength of cotton yarn after the same period of incubation. For the tensile strength studies cotton yarn was incubated in test tubes, half immersed in the nutrient liquid recommended by Marsh, Bollen­bacher, Butler and Raper (1949). The isolates used in these experiments were all derived from PVC covered cotton conveyor belt exposed in coal mines. The results are given in Table 3.

Together with the results from these studies, Table 3 lists the cellulolytic activity of these fungi as given by Sin (1951) compiled from the results of previous workers.

Discussion

In comparing the present method with results obtained from tensile strength studies, two features are of major importance. The first of these is the reliability of the results obtained. Statistical analysis (A.S.T.M., 1957) of the tensile strength loss results indicates that at the level of variation encountered in this study, using 5 replicates, differences of 10-15% in average tensile strength losses were significant. In the case of the particle counting results, differences of between 20-25% were sigoificant in a similar analysis. This comparatively low reliability is however increased considerably if the 5 particle counting results (marked (x) in Table 3) which showed excessive variance, are deleted. In this case differences in particle count of 15% are found to be sigoificant, a figure which compares well with that from tensile strength studies, in which more replicates were studied.

18

%clearing after 10 days at 25°C

Whatman ~F 11 Cotton Yarn powder

II 17

83 93

62 77

73 84

77 93

The second important feature in which methods might be compared, is the ease of operation. In this respect, the particle counting method involves no specialised equipment, and thus has a considerable advantage over tensile strength studies. On the other hand it is more time-consuming.

It is apparent from Table 3 that for many isolates, particle counting and tensile strength, studies result in similar estimates of activity, indicating that the present method is useful for classifying isolates with regard to activity, particularly in comparative studies of a range of organisms, as studied here. In addition both methods show a good agreement with Siu's qualitative data (Siu 1951), though the subjective nature of Sin's terms makes this a more difficult comparison.

In a few cases there is more disparity, notably with Verticillium /ateritium, Aspergillus niger, A. nidulans and A. ustus, which all show higher activity when assayed by tensile strength losses. Conversely Peni­cillium eye/opium and Aspergillus oryzae show higher activity when assayed by particle counting. Although the latter effect may be due to degradation during ball milling, or the finely divided form of the cellulose, the former is more difficult to explain. It is suggested that reduced activity in particle counting estimates may result from the accumulation of inhibitory products around the culture in the petri dish studies, which would be expected to drain away or be dis­persed in the tensile strength studies in which the yarns were incubated vertically in a liquid medium. Bravery (1968) has shown the effect of non-cellulosic carbon sources in Eggins and Pugh medium in delaying the development of the cellulolytic activity of certain isolates, but this factor is probably not involved here. The cotton yam used is impure and contains 8% of non-cellulosic carbon compounds (fats, waxes, pectins, organic acids, free sugars etc.) so that differ­ences in the non-cellulosic carbon content of the media for particle counting, and for tensile strength studies are probably not important.

A simple method for the assay of the cellulolytic activity of fungi. J. H. Walsh and C. S. Stewart.

TABLE 3-Cellulolytic activity of fungi; decrease in yard particle count,

compared to yarn tensile strength losses

(Incubation 10 days at 25'C)

Average Replicate Average %Loss of* Organism Initial Final Final % Tensile

Count Count Count Decrease Strength

None (Control) 89 90 90 91 90 0 0

Aspergillus nidulans 89 70 69 74 71 21 41

Aspergillus niger 89 78 80 79 79 11 33

Aspergillus oryzae 92 50 41 44 45 51 12

Aspergillus recurvatus 90 67 61 58 62 31 30

Aspergillus ustus 91 75 70 S3(x) 66 27 54

Cephalosporium sp. 91 2 14 2l(x) 12 87 92

Chaetomium g/obosum 88 I 9 - 5 94 86

Circinella mucoroides 90 83 78 88 83 8 5

Doratomyces purpureofuscus 91 35 19 17(x) 24 74 88

Fusarium culmorum 90 21 15 15 17 81 66

Fusarium moniliforme 89 17 12 11 13 85 73

Fusarium so/ani 90 26 34 30 30 66 75

Geomyces cretaceus 89 29 33 29 30 66 53

Gliocladium roseum 91 16 14 8 13 86 87

Gft'omastix sp. 91 4 0 I 2 98 82

Memnoniella echinata 88 0 4 0 I 98 100

Mucor racemosus 92 86 86 90 87 6 0

Penecillium crustosum 88 79 76 80 78 11 11

Penecillium cyclopium 90 70 63 73 69 23 5

Penecillium notatum 90 82 77 82 80 11 26

Rhizopus oryzae 91 87 92 89 89 2 12

Stachybotrys atra 92 9 9 30(x) 16 83 91

Streptomyces sp. 90 89 91 91 90 0 0

Trichoderma koningi 88 2 6 0 3 97 75

Tritirachium roseum 90 83 87 84 85 6 14

Verticlllium /ateritlum 93 66 61 50(x) 59 37 92

(x) = excessive variation * = average of 5 detenninations

Siu's Estimate

-

Weak

Nonet

None (Jermyn, 1952) Not studied

Positive

Moderate (some strains) Very strong

None (other Circ. species) Not studied

Definite

Moderate

Moderate

Not studied

Moderate

Strong (G. convoluta) Strong

None

Not studied

Not studied

None

None

Strong

Varies according to species Stroog

None

Definite

t = Simpson and March (1964) found some strains were active.

19

A simple method for the assay of the cellulolytic activity of fungi. J. H. Walsh and C. S. Stewart.

These disparities noted above serve to emphasise that in all probability, no single method yields an absolute value for cellulolytic activity. The technique used for any particular method may modify the results obtained. This is reaffirmed by the results in Table 2, since had Whatman cellulose powder CF I I been used in the general comparison listed in Table 3, a different set of figures would have been obtained, although the order of activity of the isolates relative to each other would have been much the same.

Bearing in mind the many factors which affect the relevance of results obtained by the methods available, it is felt that the present method gives results as valid as those obtained by any other method, avoiding the criticisms of existing clearing methods. At its best, the replication obtained is of a similar order to that of tensile strength studies on yarn using 5 replicates, a method involving much more specialised apparatus. Although the method was subject to occasional (5/78) erratic results, this is not thought to detract from the usefulness of the results. Some other methods (e.g. respirometric studies, Kaplan, 1964) have also shown this tendency, but have yielded many useful results.

Although the emphasis in this paper has been on the use of yarn cellulose powder, it is felt that the results quoted in the comparison of ball milled yarn and Whatman cellulose powder establish that the method is equally useful when the latter type of particles are used. Because of the ease of preparation of ball-milled Whatman cellulose powder, it is felt that this is probably the better substrate to use, where a simple comparison of one culture with another is required without reference to estimates of activity by other methods.

One point which has arisen in writing up where it is felt the method might be improved, lies in the selection of the area to be counted. In the present study, measurements were made I em. from the colony edge. It may be that the counting region would be better situated at a fraction (e.g. tl of the colony radius from the edge, so that the hyphae in the area investigated are of equal age in all cultures.

Acknowledgements

Identifications of the fungi studied were carried out at the C.M.I. (Kew) by J. J. Elphick, Dr. A. H. S. Onions and Dr. C. Booth, and we are grateful for their expert advice.

20

We wish to record our appreciation of a grant in aid of research which was donated by the National Coal Board. The views expressed, however, are those of the authors, and not necessarily those of the Board.

References

Aschan, K. and Norkrans, B. (1953). Physiologia Pl. 6, 564-583. A study in the cellulolytic variation for wildtypes and mutants of Collybia velutipes. I .

A. S. T. M. (1957). D684-57, pp. 47-53. Supplement to the book of A.S.T.M. standards including leota­lives. Part 7. Methods of test for the resistance of textile materials to micro-organisms.

Bravery, A. F. (I968) J. Sci. Fd. Agric., 19, 133-135. Microbiological breakdown of cellulose in the presence of alternative carbon sources.

Eggins, H. 0. W. and Pugh, G. J. F. (1962). Nature, 193, 94-95. Isolation of cellulose decomposing fungi from soil.

Jerrnyn, M. A. (1952). Aust. J. Bioi. Sci., 5, 409-432. Fungal Cellulases, I. General properties of on­purified enzyme preparations from Aspergillus oryzae.

Kaplan, A. M. (I964). Devs. Ind. Microbiol., 6, 191-201. Comments on the respirometric technique for assessment of micro-biological susceptibility of materials.

Marsh, P. B., Bollenbacher, K., Butler, M. L. and Raper, K. B. (1949). Text. Res. J., 19, 462-484. The fungi concerned in fabric deterioration, 2. Their ability to decompose cellulose.

Rautela, G. S. and Cowling, E. B. (1966). Appl. Microbiol., 14, 892-898. Simple cultural test for relative cellulolytic activity of fungi.

Savory, J. G., Mather, B., Maitland, C. C. and Selby, K. (I967). Cherny. Ind., No. 4, 153-I54. Jan. 28th, I967. Assay of fungi for cellulolytic activity.

Simpson, M. E. and Marsh, P. B. (I964). U.S. Dept. Agriculture, Tech. Bull., No. 1303. Cellulose de­composition by the Aspergilli.

Siu, R. G. H. (I95I). Microbial Decomposition of Cellulose. New York, Reinhold.

Traxler, R. W. and Bernard, J. M. Int. Biodetn Bull., 5, (1), 21-25 (1969). The utilization of n-alkanes by Pseudomonas aeruginosa under conditions of anaerobiosis. I. Preliminary observation.

THE UTILIZATION OF ·N-ALKANES BY PSEUDOMONAS AERUGINOSA UNDER CONDffiONS OF ANAEROBIOSIS.

I. PRELIMINARY OBSERVATION. R. W. Traxler' and J. M. Bernard'

Summary. This paper describes the utilization of n-ocatane and n-hexadecane by Pseudomonas aeruginosa strain I96Aa under anaerobic conditions as well as the reduction of nitrate by this organism.

L'utilisation par Pseudomonas aeruginosa des n-alkanes dans des conditions d'nnaerobiose. I. Observations prcliminaires. Dans cet article, on trouve une description de l'utilisation den-octane ct de n-hexadecane par Ia souche 196Aa de Pseudomonas aeruginosa, dans des conditions anaCrobiques, ainsi que de Ia reduction des nitrates par cet organisme.

There have been innumerable papers which describe the utilization of n-alkanes by micro-organisms in the presence of atmospheric oxygen. It seems logical that such a reduced substrate as an alkane should be oxidized by some micro-organism in the absence of molecular oxygen if the alkane can be induced to lose )lydrogen so as to form a double bond between two adjacent carbon atoms. Azoulay, et a/, (1963) have shown Pseudomonas aeruginosa strain Sol20 to possess the capacity to cause a dehydrogenation of n-heptane. 11Iis finding suggests that indeed biochemical mechan­isms are available whereby a bacterium could cause oxidation of an n-alkane in the absence of molecular oxygen. Hansen and Kallio (1957) report the inability of nitrate to serve as a terminal oxidant for hydro­carbons with Pseudomonas stutzeri. These workers used only resting cell preparations in their experiments which should be satisfactory but which would not detect a metabolic event which operates only under active growth conditions. One would expect to find nitrogen as a product of nitrate reduction only in the case of true dissimilatory nitrate reduction. If inciden­tal dissimilatory nitrate reduction or nitrate assimila­tion were the functional event in the cells, then ammonia would be an end product of the reduction process and nitrogen would not be liberated. Updegraff and Wren (1954) present evidence which suggests that many strains of Desu!fovibrio are unable to attack hexadecane, under anaerobic conditions with sulfate as the terminal hydrogen acceptor. It is mainly on the basis of these two papers and the demonstration of 0" incorporation in aerobic test systems that the anaerobic utilization of n-alkanes is generally not considered possible. In contrast to these results Feely and Kulp (1957) have shown that Desu!fovibrio will grow with petroleum as

Die Nutzung von N-Alkanen durch Pseudomonas aeruginosa unter nnaeroben Bedingungen. I. VorUiufige Beobachtung. Die Arbeit beschreibt die Nutzung von n-Oktan und n-Hexadekan dlirch Pseudomonas aeruginosa, Stamm 196Aa, unter anearoben Bedingungen sowie die Nitratreduktion durch diesen Organis­mus. La otillzaciOn de los alkanes N por Pseudomonas aeruginosa bajo las condiciones de1 anaerobiosis. L Observaci6n prcliminar. Este papel describe Ia utilizaci6n del octane n y del hexadecane n por Pseudomonas aeruginosa clase 1 Q6Aa bajo las condiciones anaer6bicas adem<is de la reducci6n del nitrate por este organismo.

the only source of energy and reduce sulfate under conditions where one would expect to find a lack of gaseous oxygen.

Pseudomonas aeruginosa strain 196Aa was isolated from contaminated JP-4 fuel. It has been shown to utilize n-alkanes and fatty acids. It will not utilize any of a variety of aromatic hydrocarbons. This organism is a typical pseudomonad with one polar flagellum as shown in Figure I.

Table I. Composition of mineral salts medium

Component Mg per liter

Na,HPO, 1000

KH,PO, 500

NH4N03 2500

MgS0.-7H,O 500

CaCI,.2H20 10

Fe,(SO.),.H,O 10

MnSO.-H,O 0·01

Co(N0,),·6H,O 0·005

(NHJ6Mo,0,.-4H,O 0·1

pH 6·8-7·0; Filter sterilized

'Department of Microbiology, The University of Southwestern Louisiana, Lafayette, Lonisiana 70501, U.S.A. (Copy received 4th November, 1968).

21

The utili1a tion of n-alkanes by Pseudomonas aeruginosa under conditions of anaerobiosis. I. Preliminary observation. R. W. Traxler and J . M. Bernard.

Figure 1: Germanium shadowed Pseudomonas aeruginosa strain 196Aa.

The growth of this organism was compared in mineral salts medium with glucose or with n-octane as the carbon source (Table 1). These initial experi­ments demonstrated an interesting phenomenon which is shown in Figure 2. The growth response with glucose was much better if the culture was shaken than if it was allowed to incubate under static conditions. However, when hydrocarbon served as the sole source of carbon and energy the reverse situat ion was found . The aeration efficiency of these aerobic cultures was determined by the sul fi te method (Cooper eta/., 1944)

22

and found to be 0 ·85 mM 0 2/L/min for the shaken cultures and 0·52 mM OJ L/min for the cultures in­cubated without shaking. The superior yield of cells from n-alkane with reduced aeration indicated either there was accumulation of a toxic product under higher oxygen tension o r the organism preferred to utili7.C a non-oxygen req ui ring system. We do know that this organism is sensitive to high concentrations (0·1 %) of fatty acids and therefore the accumulation of fatty acids from n-octane cou ld be responsible for the lower cell yields.

,

The utilization of n-alkanes by Pseudomonas aeruginosa under conditions of anaerobiosis. I. Preliminary observation. R. W. Traxler and J. M. Bernard.

300 OCTANE GLUCOSE

r--- 500

., I /-········· !: I z 200 I / ____ ~ ... I ... Ill I .. llll: 300 ;r • I ::1: /I ... ,.,.~~~--~~~~~-~~~~~~-

~ 0 100

,, ;I Ill ,, 0 i/

If f f! 100

20 30 40 10 30 50

TIME, HOURS

Figure 2: Growth response of Pseudomonas aeruginosa on octane (2% u/v) and glucose (1% w/v) under static (---)and shake ( •.. ) conditions, at 30°C,

With the low aeration efficiency demonstrated for the static cultures it was possible that the metabolism of the organism was essentially anaerobic rather than aerobic. The medium contained nitrate (as NH,NOJ which could serve as an electron acceptor and which was shown to disappear from the medium. Table 2 summarizes the growth response obtained when the organism was grown under aerobic and anaerobic conditions on n.octane. The lower the oxygen tension in the culture medium the greater the cell yield, but the greater the time required to reach maximum growth.

The fate of ammonia and nitrate was followed in the aerobic cultures under static conditions. Figure 3 demonstrates that ammonia was used initially by the lag phase and early exponential phase culture. As the cell mass increased and oxygen became limiting in the latter portion of the exponential phase of growth nitrate was rapidly reduced to nitrite. The late increase in ammonia shown in this experiment could be due either to the reduction of nitrite to .ammonia or to the

23

endogenous release of ammonia by the stationary phase cells. This point has not been clarified at this time.

TABLE 2

Growth yield under different aeration conditions

Culture Conditions

Maximum Growth

Time Klett Dry Weight KLaC (hours) Units Cells mg/ml

Shake-aerobic 18 125

Static-aerobic 50 275

Static-anaerobic 96 300

1·3

1·4

1·8

0·85

0·52

0·00

Substrate, 2% n•octane; Temperature 30°C; KLaC in mM 0,/liter/minute.

The utilization of n-alkanes by Pseudomonas aeruginosa under conditions of anaerobiosis. I. Preliminary observation. R. W. Traxler and J. M. Bernard.

300

N02 NH• 4 .........

100 ' . l \ . . I \

., 80 !: 200 .a z \ ::::»

/ .............. , ... \ . ... 60 Ill

/ ' .6 ... :II!

:X/ ', • :z: /\ ' 40 ...

......... ~ ········ .4 3:100 . . ... \ 0

........ ························· \ Ill: C!)

\'looo•n•••••u•• .2 20

'

10 20 30 40 50 60 TIME, HOURS

Figure 3: Relationship between ammonia concentration ( ... ), nitrite accumulation(---), and growth(-) of Pseudomonas aeruginosa strain 196Aa on n-octane under static conditions of culture at 30oC.

Anaerobic cultures were grown in a National Appliance Company, Model 3640, Anaerobi~ Incuba­tor. The incubator was evacuated to 28 mches of mercury and back-filled with pure helium gas. Th cycle was repeated four times at which point the percentage of oxygen remaining in the chamber was less than 0 ·0006 per cent. In some experiments nitrogen was used for replacement rather than helium. The growth response was the same with either gas. Anaero­bic controls were a tube of Bacillus megaterium and Clostridium bifermentans placed in the chamber and a tube of decolorized methylene blue. The experiment was not considered valid unless there was growth of the C/ostridum, no growth of the Bacillus, and the methylene blue solution remained colorless. All hydro­carbon cultures were inoculated with I ml of a 200 Klett Unit n.octane grown cell suspension. Octane was

24

provided to the organism in the vapour phase and hexadecane added directly to the medium.

Three different organisms have been tested for the capacity to utilize n-alkanes in the absence of gaseous oxygen. Pseudomonas aeruginosa strain 196Aa from our laboratory, Pseudomonas aeruginosa strain Sol. 20 obtained from Dr. J. C. Senez (CNRS, Marsetlle, France), and Bacterium 7EIC obtained fro_m th~ stock culture collection of the Department of Microbiology, The University of Texas. Organism 7EIC would not grow under anaerobic conditions in our test system but the two pseudomonads gave the growth respon~ shown in Figure 4. The growth with the Sol 20 stram is feeble and may not be considered representative of alkane utilization. The response of the 196Aa strain is satisfactory evidence for growth obtained from an n-alkane under these conditions.

j I

1

The utilization of n-alkanes by Pseudomonas aeruginosa under conditions of anaerobiosis. I. Preliminary

observation. R. W. Traxler and J. M. Bernard.

I!! z ;::)

125

100

... 75 ... Ill ... ~

//

//

// // ····························· .;".-········

/.,":.······ ~-----~·

~-::.::--·· __. .. 50

/.:.-:;.-~ ....-:::-·····

...,.,~~-·

--~······ -- ····· ························ l5

24 48 72 96

TIME, HOURS

Figure 4: Growth of Pseudomonas aeruginosa strain 196Aa (-- -) and Pseudomonas aeruginosa strain Sol 20 ( ... ) on hexadecane under anaerobic conditions obtained with helium.

It is concluded from these results that Pseudomonas aeruginosa is capable of utilizing either n-octane or n-hexadecane in the absence of molecular oxygen. Nitrate undoubtedly serves as the terminal hydrogen (electron) acceptor in the respiratory scheme rather than oxygen. Oxygen is probably introduced into the hydrocarbon molecule from water/ via a hydration mechanism, at a double bond formed by the dehydro­genation of the alkane molecule. Proof of this assump­tion rests of course on the isolation and identification of inte mediates such as an alkene and the demon­stration of enzymes capable of carrying out the proposed mechanism. Work is now underway which it is hoped will provide such proof.

25

References

Azoulay, E., Chouteau, J., and Davidovics, G. (1963). Isolement et characterisation des enzymes respons­ables de l'oxydation des hydrocarbures. Biochim. Biophys. Acta, 77, 554-567.

Cooper, C. M., Fernstrom, G. M. and Miller, S. A. (1944). Performance of agitated gas- liquid contac­tors. Ind. Engng Chern., 36. 504-509.

Feely,H. W., and Kulp,J. L. (1957), OriginofGulfCoast salt-dome sulphur deposits. Bull. Am. Assoc. Petroleum Geologists, 41, 1802"1853.

Hansen, R. W., and Kallio, R. E. (1957). Inability of nitrate to serve as a terminal oxidant for hydro­carbons. Science, 125, 1198.

Updegraff, D. M., and Wren, G. B. (1954). The release of oil from petroleum-bearing materials by sulfate-reducing bacteria. App/. Microbial., 2, 309-322.

Coursey, D. G. and Russull, J. D. Int. Biodetn Bull., 5, (1); 27-30, (1969). A note on endogenous and biodeteriorative factors in the respiration of dormant yam tubers.

A NOTE ON ENDOGENOUS AND BIODETERIORATIVE FACTORS IN THE RESPIRATION OF DORMANT YAM TUBERS

D. G. Courseyl and J.D. Russu!Jl

Summary. Yam tubers (Dioscorea rotundota) were stored at 25DC until decay or sprouting occurred~ Weight and C02 output were determined at intervals. The results suggest that loss of dry matter as C02 was the major factor influencing weight loss. The tubers cou1d be divided into two groups with low and high respiration rates: the former remained sound while the latter quickly rotted. Decayed tubers were infected with Botryodip/odia theobromae Pat. and in one case with Penicillium eye/opium Westling.

Note sur les facteurs endogCnes et de biodCtb-ioration du taux de respiration des tubercules d'igname 8 l'Ctat donnant. Les tubercules d'ignames (Dioscorea rotundata) ont CtC entrepostes a 25°C jusqu•au stade de pourriture ou de bourgeonnement. Le poids et la quantit6 de C02 Ctaient rn.esurCs A intervatles. D'aptes les r6iultats, il est pennis de suggCrer que la perte de matiere seche sous fonne de C02 Ctait le facteur prCpondCrant influenfJant Ia perte de poids. Les tubercules pouvaient etre divisCes en deux groupes, suivant les taux de respiration bas ou eh~ve: le premier groupe Ctait rest6 sain landis que le second a pourri rapidement. On a trouve dans les tubercules pourris Botryodiplodia theobromae Pat. et, dans un cas, Penicillium cyclopium Westling.

The tubers of yams, principally Dioscorea rotundato Poir. and D. a/ota L., are important foods in many tropical countries, the production being of the order of 20 million tons/annum (Coursey, 1967a).

However, little attention has been given to their post-harvest behaviour. Storage methods are general­ly primitive, and losses are severe, amounting to more than a million tons/annum globally (Coursey, 1967b). These losses appear to arise (a) from the natural metabolic processes of the dormant tubers and (b) from attack by micro-organisms causing decay.

Preliminary respiratory studies on whole D. rotun­da/a tubers have been described (Hayward, 1959; Hayward and Onyearu, 1962). The first indicates that the carbon dioxide output may vary between zero and SO mg. CO,jkg. fresh weight/hour, but the tech­niques are open to criticism; while the second suggests 5 to 10 mg.fkg./br. Gane and Robinson (unpublished) found rates of the order of 100 mg./kg./hr., but their material was old and highly deteriorated, and this high apparent respiration may have been due mainly to biodeteriogens. The respiration of slices of yam tuber tissue has been studied by Coursey et ol. (1966). The organisms responsible for decay in yams have been studied by several workers (reviewed by Coursey, 1967b).

Experiments were conducted using D. rotundata cv. "Labreko" purchased in Accra, Ghana. The material was recently harvested (ca. 3 days) and consisted of "first crop'" tubers (i.e. slightly immature tubers,

Ein kurzer Berlcht Uber endogene und durch Organismen hervor­gerufene Eini!Usse auf die Atmung von rohenden Jamswurzel­.lmollen. Jamswurzelknollen (Dioscorea rotunclata) wurden bei 25°C gegert bis zum Auftreten von Fdule oder Ausspriessen. In verschiedenen Zeitabsdi.nden wurden Gewicht und 002"" Abgabe bestimmt. Die Ergebnisse deuten darauf hin, dass der Verlust an Trockensubstanz, wie C02, der Hauptgrund flir den Gewichtsverlust war. Die Knollen konnten in Gruppen mit hohcr und mit niedriger Atmungsintensitiit eingeteilt werden. Erstere blieb gesund, w3hrend die zweite schnell verdarb. Verdorbene Knollen waren von Botryodiplodia theobromae Pat. tm.d in einem Fall von Penicillium eye/opium Westling befa11en.

Apuntes sobre los factures end6genos y blodeterlorativos en Ia respiracl6n de los tuberculos inactivos del yam. Se almacenaron a 25 grados C unos tubCrculos de yam (Dioscorea rotunda/a) hasta que emperzaron a echar botones o a pudrirse. Se deter­minaron a intervalos el peso y Ia producci6n de C02. Los resultados sugerian que Ia ¢rdida de materia seca como el C02 era el factor principal que inftufa en la pCrdida del peso. Result6 posible dividir los tuberculos en dos clases segUn su respiraci6n rApida o lenta; Cstos quedaron en buen estado mientras esos se pudrieron rApidamente. Se inf1Cion6 a los tubCrculos pudridos con Botryodiplodia theobromae. Pat. y en una ocasi6n con e1 Penicillium eye/opium Westling.

harvested from the growing plant). Ten tubers (weights between 2287 g. and 3786 g., mean 2859 g.) were selected to be as uniform as possible, and free from blemishes or decay.

These were stored at 25°C. The tubers were indivi­dually weighed at weekly or fortnightly intervals. Respiratory activity was determined at similar inter­vals by measuring CO, output by absorption in N/10 Ba(OH), and titration with standard HCI. The experiments were continued with each tuber until it either exhibited marked decay, or began to sprout. The results of respiratory measurements together with changes in weight, are given in the Table. Tubers which decayed during the experiment were found to be infected with Botryodip/odia theobromae Pat. (IMI 134625 to 134628) and in one case with Peni­cillium eye/opium Westling (lMI 134629).

A statistical analysis of the results was made by examining the regressions of weight loss on respiration rate. Each correlation coefficient was found to be significant at the 95% level of confidence, while using all the observations, a correlation coefficient of + 0.746 was obtained, which may be regarded as highly significant.

Loss of dry matter as CO, appears therefore to be the major factor influencing weight loss in yams, as has been suggested elsewhere (Coursey, 1961; 1967a; 1967b). This loss of dry matter is accompanied by moisture loss, as the dry matter content of the yams varies little during storage (Coursey, 1961).

'Tropical Products Institute, 56/62 Gray's Inn Road, London, W.C.l. (Copy received 19th December, 1968).

27

A note on endogenous and biodeteriorative factors in the respiration of dormant yam tubers. D. G. Coursey and J. D. Russull

Inspection of the results shows that the tubers may be divided between two groups. Group I includes those of comparatively low respiration rates, varying only slowly with time. Group II includes those with high respiration rates, which tended to vary erratically. All the tubers in Group II, although initially sound, quickly became rotten, while those of Group I remained sound until the end of the experiment, when sprouting occurred. Three individual tubers in Group I suddenly developed enhanced, fluctuating respiration rates during the course of the experiment, and, shortly afterwards, became rotten; they are therefore regarded as having moved into Group II. (see Figure).

It was noted that respiration rates in excess of about 65 mg./kg./hr. were associated with visible decay.

The marked difference in behaviour exhibited by the two groups of tubers is in agreement with earlier field experiments (Anon, 1937; Coursey, 1961) where it was shown that visible decay is associated with enhanced weight loss. Similar effects are, of course well known in many types of produce.

Of the two fungi isolated, B. theobromane has previously been reported as a storage rot of yams in several parts of West Mrica (Coursey, 1967b). P. eye/opium has not previously been reported in yams, but is common in association with decay in the hypogenous organs of other Liliales (Raper and Thorn, 1949).

Acknowledgements

The collection and supply of the experimental material was arranged by Prof. J. S. Matthews of the University of Ghana.

28

Mycological isolations were made by Mrs. H. C. Aldridge, and identifications by Mrs. A. Wallbridge; these were confirmed by the Commonwealth Myco­logical Institute. Statistical analyses were conducted by Mr. R. Pope.

This note is published by permission of the Director, Tropical Products Institute, Ministry of Overseas Development.

References

Anon. (1937). Annual Report, Puerto Rico Agricultural Experiment Station, U.S.D.A. 1937.

Coursey, D. G. (1961). The magnitude and origins of storage losses in Nigerian yams. J. Sci. Fd Agric., 12, 574.

Coursey, D. G. (1967a). Yams. Longmans, Green and Co. Ltd., London.

Coursey, D. G.l!967b). Yarn Storage. J. Stored Prod. Res., 2, 229.

Coursey, D. G., Fellows, Linda, E., and Coulson, C. B. (1966). Respiration of Yam Tuber Tissue. Nature Lond., 210, 1292.

Hayward, L. A. W. (1959). Annual Report W. Afr. Stored Prod. Res. Unit, 1959.

Hayward, L. A. W. and Onyearu, A. K. (1962). Annual Report W. Afr. Stored Prod. Res. Unit, 1962.

Raper, K. B. and Thorn, C. (1949). A Manual of the Penicillia. Williams and Wilkins Co., Baltimore.

A note on endogenous and biodeteriorative factors in the respiration of dormant yam tubers. D. G. Coursey and J. D. Russull

RE.SPIRATION RATE. (m9. COr_/ks. tresh wei<;3ht /hr.)

"' 0

0 0

0

(/) -1 0 ;o :1>' G'l rn

,........ 0.. 0.

...c II\ ~ 0

N 0 0

,. U\ 0

0 ... t; os-

:>E

' ~----- ----------- I ' -------r-' - ---)(

'x, \ \c ' ' \c.._ ......

......... ')(

-- --' ..... -----

Relationship of respiratory activity of dormant yam tubers to duration of storage.

Ill> 0

The full lines represent envelopes to curves of results obtained with individual tubers, enclosing areas I and 11 (see text). Dashed lines indicate behaviour of three individual tubers which moved from Group I to Group II during the experiment. The horizontal dashed line indicates the level of respiratory activity associated with obvious ' decay. · Arrow indicates time at which sprouting of the tubers was observed.

29

Table 1

Respiratory Activity and Weight Losses on Yam Tubers

Week No. I 2 3 4 5 6 7 8 10 12 14 16 18 20 22 24 26 27 28 29 30 31 32 33 34 35

Tuber No.1 Initial Weight 2344 g.

Respiration Rate (mg C02fkg/hr.) 13·0 15-6 19·5 23-7 28·8 38·2 46·7 55·2 73·7 107-2 44·2 29·3 13·3 20·2 37•3 39-6 63·5 . . Weight (as % of original) 100 99·5 99·0 98·4 97-6 97·0 96·2 95·0 92·9 90·6 88·5 86·4 84·6 82·8 80·8 78·6 75,8 D1scontmucd

Tu!Jer No.2 Initial Weight 2807 g.

Respiration Rate (mg CO,fkg/hr.) 16·0 26·0 17-6 14·9 14·1 13·0 14·7 16·2 142·0 132·0<220·0 D'scont'nued Weight (as % or original) .100 99·5 98·9 98·3 97-9 97•5 97-2 96•9 92•4 83•1 72•8 I I

Tuber No.3 Initial Weight 2983 g.

Respiration Rate (mg CO,fkg/hr.) 19·4 18·6 18·5 15·8 15·0 13·2 14·0 13-0 19·9 22·8 26·7 38·3 46·9 48·7 59·9 47-6 61·2 63·4 . . We1ght (as % of original) 100 99·3 98·7 98·3 97·7 97·3 96·9 96·3 95·4 94·0 92·5 90·3 87-6 84·4 81·0 77·0 73·2 71 •2 D1scontmued

Tuber No.4 Initial Weight 3449 g.

Respiration Rate (mg C02!kg/hr.) 18·6 17·5 16·2 12-8 14·2 13·0 9-8 12-4 11-4 !JoB 9·2 9·2 9·2 40·3 54·4 76·0 ~:ij Discontinued Weight (as % of original) 100 99·3 98·7 98-4 97·9 97-4 97·0 96·6 95·8 95·2 94·3 93·5 92·6 90·9 87-7 84·2

~ Tuber No.5

Initial Weight 3005 g. Respiration Rate (m8 CO 2!kgfhr.) IN 54·3 58·8 49-1 29·3 39·5 50'4 Discontinued Weight (as %of original) 100 98·3 96·5 94·4 92·5 90·2 87-6

Tuber No.6 Wtial Weight 2288 g.

Respiration Rate (mg C02!kgfhr.) 23·0 20·1 21·5 11·5 15·1 14·0 12·5 11'6 11·3 8·6 7-9 11·0 14-1 12·6 15·3 19·2 21-1 20·8 17-6 20·0 21-6 24·4 29·2 Discontinued Weight (as % of original) 100 99·3 98·7 98·2 97-6 97·2 96·8 96·4 95-6 94-7 94·0 93·4 92·2 90·3 88·1 85-4 82·6 81· 0 79-6 78·0 76·8 75·4 74·2

Tuber No.7 Discontinued Initial Weight 3787 g. Respiration Rate (mg C02!kg/hr.) 13•8 12·1 14·9 13-2 11·9 11·1 11·2 11'6 9·8 11·3 9·0 8·1 9-4 11·7 13·1 16·5 19·0 20·0 17·5 26·4 20·4 22·3 24·0 37·0 25-6 29-6 Weight (as % of original) 100 99·5 99·0 98·5 98·1 97·9 97-6 97·3 96·6 95·3 94-2 93-6 92-8 91·4 89-4 87·3 85·0 83-8 82·5 81·4 80·4 79·1 77-8 76·7 75·6 74-6

Tuber No.8 Discontinued Initial Weight 2420 g. Respiration Rate (mg C02!kg/hr.) 12-4 15-4 15·0 12·0 11·2 10·5 10·7 9·0 8·8 8·8 7-8 8·6 8·8 10·5 12·9 18·3 19·9 21·0 17-2 18·1 20·2 20·2 23·0 27·7 23-4 22·2 Weight (as % of original) 100 99·4 99·0 98·6 98·2 97-8 97·5 97-4 96·6 96·2 95·7 95·2 94·6 93-7 91·6 89·0 86·3 85·0 83-4 81·7 80·8 79-4 77-8 76·6 75-6 74·6

Tuber No.9 Initial Weight 2837 g.

Respiration Rate (mg CO,/kg/hr.) 45·5 38·3 54·2 48·7 41·0 59·0 59·3 57·0 32·0 43·9 39-4 41·2 29·0 26·1 34·9 47·3 5o-4 66·6 . . Weight (as % of original) 100 98·5 97-1 95-6 94·0 92-6 91·1 89·3 86·5 83-3 80·0 76·5 73·0 69-4 65-8 62-4 59·1 57,7 Dtscontmued

TuberNo.lO Initial Weight 2626 g.

Respiration Rate (mg CO,/kg/hr.) 40·3 34·3 32-7 33·6 33·5 4o-4 41·4 43·9 47·0 32·1 33-6 44·1 68·0 60·7 53·2 49-6 48·8 64-6 o· · d Weight (as % of original) 100 99·0 98·0 97-2 96·3 95·5 94·5 93·3 91-3 89·1 86·9 84·5 81-6 78·0 74·3 70·7 67-2 65•4 ISContmue

---- ·-·

•

·--

BOOK REVIEWS

BIODETERIORATION OF MATERIALS. MICROBIOLOGICAL AND ALLIED ASPECTS

Edited by A. Harry Walters and John J. Elphick.

(Elsevier Publishing Co. Ltd., Barking, Essex, 1968. x + 740 pp. Price £12. 10. 0.)

This book records the proceedings of the I st. International Biodeterioration Symposium held in September 1968, and I must first indicate my pleasure at being able to review this book while the Symposium itself remains fresh in the memory. The editors are to be congratulated for organising a very large amount of material-67 separate papers in all- in so short a time. An editorial note apologises for any errors which may have slipped through due to rapid processing and at the same time pays tribute to the publishers and printers. The apology is hardly necessary, the tribute well earned, for this book has been.produced to a very high standard and is pleasant to handle and easy to read.

Several other features of this book which may be attributable to editorial or publishing policy make the contents easy to assimilate. All the contributions are commendably brief, none exceeds ten pages of text if tables and illustrations are excluded. Within a brief space each manages to include a great deal of material and a ready understanding of this material is greatly assisted by a uniform policy of splitting each paper into short sub­sections. Each such sub-section is clearly headed so that the content of the article can be assessed at a glance. Where further subdivisions are necessary these too are clearly picked out in heavy type. A second feature which assists both understanding and brevity is the reproduction of large numbers of tables and diagrams, together with appreciable numbers of photographs which are particularly valuable where topics or materials unfamiliar to the majority of readers are dealt with. In short the overall effect is that of a well produced textbook, and this cannot be said of many symposium proceedings.

From the point of view of content this book is a very valuable summary of the sort of problems faced, and the sort of work being done in biodeterioration today. Its 700-odd pages contain a great deal of information and the contents list which accompanies this review shows the width of the field covered. A by-product of the large number of relatively short papers is the large number of references which they cite when taken together. The result is a comprehensive and up-to-date bibliography of biodeterioration work. While not detracting from the great value of this volume however, I do question whether it fully achieves the aims of the Symposium Organizing Committee. From the number of articles and the wide interests covered, I get the impression that the intention was to produce a comprehensive account of biodeterioration. This was a very sound aim in view of the recent establishment of biodeterioration as a separate disclipline. A comprehensive account would serve both as an introduction for workers in allied disciplines, and as a statement of the 'state of the art' for workers in biodeteriora­tion. However I question whether the balance and arrangement of papers in this book will give a correct im­pression of biodeterioration to outsiders, and whether there are sufficient papers attempting to increase the aware­ness amongst biodeteriorationists of the significance of some aspects of fundamental microbiology to their work.

Taking the point of balance first. The symposium adopted the policy of having longer contributions at the morning sessions outlining large areas of biodeterioration work (Parts I, II and V) with supporting detail in the shorter contributions of the afternoon. The balance of the longer review articles is about right, fairly reflecting the areas of interest in biodeterioration. Two of them particularly (Dr. Iverson on the microbial corrosion of metals, and Drs. Traxler and Flannery on hydrocarbon degradation) provide excellent brief summaries of topics which are not easily available elsewhere. Dr. Hueck's appraisal of the whole field is valuable in setting the tone of the symposium, but one or two of the others perhaps put too much emphasis on theoretical aspects of their subject. Dr. Selby's account of cellulose biodegradation on the other hand, by dealing with a more restricted field than the other reviews, incorporates a very full account of practical results in this field.

It is in the other sections which cover the afternoon sessions that I feel an unbalanced view may be presented to the outsider. Aspects of timber decay occupy almost a quarter of the book, whilst consideration of all other materials occupies only one third. The account of timber decay is admittedly a good one. The section on ecological aspects of biO<\eterioration, and the section on enzymes and physiology of wood,destroying organisms, taken together with Dr. Selby's article, provides an excellent account of the subject. I feel that a similar comprehensive coverage could have been given to many other topics, such as hydrocarbon microbiology, if space had allowed. The fact that such coverage has been given only to timber may create the impression in an outsider that bio­deterioration work is still mainly orientated towards traditional natural materials.

It is in these sections too that I feel the arrangement could be improved. It is unfortunate that no attempt was made in publication to separate the two styles of article which are included in these afternoon sessions. Most such contributions can be classified either as authoritative reviews of a limited area of work-for example deterioration problems in specific industries, or in the use of particnlar materials-or as detailed accounts of personal results. The inclusion of the latter with the review type of article perhaps gives these particular pieces of work undue emphasis. This is particularly true where a review of deterioration of paint and paint illms is followed

31

by an account of one series of tests of different fungicides in latex plants. Similarly a general article on the degrada­tion of lubricant oils and emulsions is followed by experimental results using one treatment-gamma radiation­on one type of emulsion-cutting oil. In future publications I feel that it would be valuable to clearly distinguish and possibly to separate reviews and original work.

The question of the content of fundamental microbiology is of more concern to people working within the discipline of biodeterioration. As I see it, one of the reasons for creating such a discipline is to bring together workers studying deterioration of many diverse materials by emphasising the common factor of the organism in their work. If this is so then a biodeterioration symposium should consider both the diverse materials, as this one does, and also relevant aspects of microbiology. The excellent paper by Drs. Mitchell and Shewen on aspects of taxonomy shows just how important wprk in this branch of microbiology may be to studies ofbiodeterioration, but this paper is the ·only representative of such an approach. Topics such as the formation, distribution and germination of spores, of the mechanisms of membrane transport might be relevant to biodeterioration work. A particular aspect of the latter is involved, in fact, in a research paper on the entry of a biocide into cells. In view of the many mechanisms for genetic assortment in microorganisms, some reference to this question might be appropriate. The importance of this point is recognized by both plant and animal pathologists. Similarly, in a field where many workers study the results of the action of adaptive enzymes, some comment on the mole­cular biology of the control of enzyme formation and activation might be useful. The question of time and space is obviously involved here, but I feel that one or two topics such as these might well have replaced some of the research papers since the tenor of this symposium is slanted toward a review treatment anyway.

In one other respect I would question the choice of contents. The title of this book bears the subscript 'microbiological and allied aspects' and the latter seem to be represented by marine fouling. While I do not question the status of marine fouling as an important aspect of deterioration I do wonder how closely it is allied to micro­biology, if one considers the relevance of results with microorganisms to marine fouling, and vice versa. Certainly the paper of Drs. Dolgopolskaya and Gurevich relates fouling to the growth of bacterial slime, but the other papers in this section seem to have more in common with invertebrate biology, an impression confirmed by the references they cite. There is a large sector of biodeterioration concerned with damage caused by invertebrates, excluded in this symposium but perhaps to be considered in the future. It is surely with this sector of biodeteriora­tion that marine fouling is more naturally allied.

Despite these criticisms this symposium has produced a very valuable book, and one which I welcome as perhaps the first book to describe the whole field of microbial degradation since 'The Deterioration of Materials' by G. A. Greathouse and C. J. Wessel, published in 1954. As such it is to be hoped that it will come to the notice of workers outside the immediate field of biodeterioration. General microbiologists may be surprised at the extent of this field of applied microbiology which IS given scant recognition in the usually medically orientated courses and textbooks. It may also come as a surprise to some engineers and chemists that microorganisms show sufficient versatility to allow them to intrude significantly in the most unexpected situations. Finally, for those already in the field of biodeterioration, the production of such a professional volume may help to establish their work as a distinct and legitimate branch of science. As a result the comment 'Biodeterioration! What's that?' may be Jess often heard in the future.

J. Walsh.

CONTENTS

PART I FUNDAMENTALS OF BIODETERIORATION

The role of Government in international co-operative research J, KNOX (U.K.)

The biodeterioration of materials-an appraisal H, J, HUECK (NETI:IERLANDS)

Aspects of taxonomy with respect to biodeterioration T. 0. MITCHELL and J. M. SHEW AN (U.K.)

Ecological aspects of biodeterioration H. 0. W. EGGINS (U.K.)

PART IT MECHANISMS OF BIODETERIORATION

Mechanisms of microbial corrosion W. P. IVERSON (U.S.A.)

Mechanisms of hydrocarbon degradation R. W. TRAXLER and W. L. FLANNERY (U.S.A.)

Mechanisms of marine fouling D. R. HOUGHTON (U.K.)

Mechanisms of biodegradation of cellulose K, SELBY (U,K,)

32

PART ill

ECOLOGICAL ASPECTS OF BIODETERIORATION

Factors in establishing microbial populations on biologically inert surfaces

R. A. RASMUSSEN, R. S. HUlTON and R. J. GARNER (U.S.A,)

Protection of sensitive components from microbial contamina­tion

M. H, BENGSON and J. R. GILLIS (U.S.A.)

Microbiological deterioration of materials in deep mines B. J. ZYSKA (POLAND)

Some techniques to investigate the colonization of cellulosic and wood substrates

H, 0. W. EGGINS, K. A. MALIK and R. F. SHARP (U.K.)

Fungal spom of the air at the Joint Tropical Research Unit, Tnnisfail, Queensland

F. J. UPSHER (AUSTRAUA)

The selective iso1ation of Sphaerotilus J. M. SHARPLEY (U.S.A.)

,

PART IV

TESTING FOR BIODETERIORATION RESISTANCE

Laboratory and service tests of PVC C. C. YEAGER, (U.S.A.)

A rapid method of determining degradation of plasticized PVC by micro-organisms

J. J. CAVElT and M. N. WOODROW (U.K.)

The evaluation of rot resistance of cellulosic textiles A. 0. LLOYD (U.K.),

L'experience des normes Francaises d'essai de resistance des materiaux centre la deterioration par les micro organismes. A vantages des cultures mixtes de champignons dans les essais d'inoculation

Y. LE GRAND (FRANCE)

Some Problems posed by quality screening for biodeterioration EUNICE S. L. JONES (U.K.)

PART V CONTROL OF BIODETERIORATION

The control of biodeterioration by fungicides-philosophy A. M. KAPLAN (U.S.A.)

Protection of timber G, BECKER (GERMANY)

Prevention of biodeterioration by control of environmental conditions ·

G. AYERST (U.K.)

Biodeterioration test methodology "' 0. W.i\LCHU (SWITZERLAND)

PART VI DETERIORATION AND PROTECTION OF MATERIALS

Section 1

Fungus contamination of Aorence art-maSterpieces before and after the 1966 disaster

G. GARGANI (ITALY)

Facteurs Biologiques de l'alteration des Pierres J. POCHON (FRANCE)

The microbiological deterioration of cosmetics and pharma­ceutical products

N. J. BliTLER (U.K.) Microbiological deterioration in the paper, printing and packaging industries

R. L. HUGHES (U.K.) Infections of industrial waters

B. E. PURKISS (U.K.)

Biodetcrioration in the leather industry A. ORLITA (CZECHOSLOVAKIA)

Section 2

Investigations into the effects of micro-organisms on PVC pressure-sensitive adhesive tape and its constituents

EILEEN S. PANKHURST and MARGARF:I' J. DAVIES (U.K.)

Biodeterioration of paint and paint films R. T. ROSS, J. R. SLAOEN and L. A. WIENART (U.S.A.)

Fungicides in latex paints R. ENNINGA and W. J. BORDES (NETHERLANDS)

The anti-microbial and rot-proofing properties of cotton textiles comprising the cadmium salts of modified cellulose

L. B. QUESNEL (U.K.)

PART VII HYDROCARBON MICROBIOLOGY AND METALLIC CORROSION

Metal.arganic acid corrosion and some mechanisms associated with these corrosion processes

0. H. CALDERON, E. E. STAFFELDT and C. B. COLEMAN (U.S.A.)

Evaluating biocidal fuel additives for intermittent use in aircraft fuel systems

J. J. ELPHICK and S. K. P. HUNTER (U.K.)

The soil as a natural source of Cladosporium resinae D. G. PARBERY (AUSTRAUA)

Microbial degradation of lubricant oils and emulsions.and its engineering significance

E. C. HILL (U.K.)

Control of cutting oil deterioration with gamma radiation H. ROSSMOORE and J. G. BRAZIN (U.S.A.)

33

PART VIII ECOLOGICAL ASPECTS OF TIMBER DECAY

Microbial attack of timber and allied constructional materials 1. G. SAVORY (U.K.)

Ecology of decay fungi in birch and aspen pulpwood B. HENNINGSSON (SWEDEN)

Studies on the ecology of fungi in wooden fence posts J. F. LEVY (U.K.)

Microbial associations in the deterioration of wood under long tenn exposure

M, GREAVES and J. F. LEVY (U.K.) Ecology of fungi infecting untreated and preservative-treated sapwood of Pinus radiata D. Don

J. A. BUTCHER (NEW ZEALAND) The distribution of marine fWlgi on wood submerged in the sea

E. D. GARETH JONES (U.K.)

PART IX BIOCIDFS

Fungitoxic action of nonmetallic organic fungicides R. J. LUKENS (U.S.A.)

Action mechanisms of some organometallic preservatives B. A. RICHARDSON (U.K.)

Biocide development-the manufacturer's problems G. A. TIIOMAS (U.K.)

Some data on the relationship between fungicidal protection and pH

J. M. C. WESSELS and D. M. M. AOEMA (NETHERLANDS) The role of cell membrane permeability in determining the antimicrobial activity of 2, 4, 6-trichlorophenol at pH 6 and pHS

P. A. WOLF and M. M. SCHAEFFER (U.S.A.) Investigations on the biological activity of pentachlorophenyl esters

H. J. HUECK, J. LA BRUN, J. A. COPPER artd J. VAN HAM (NETIIER• LANDS)

PART X ENZYMES AND PHYSIOLOGY OF WOOD-DFSTROYING ORGANISMS

Some aspects of cellulose degradation in lignified cell walls P. J. BAILEY, W. LIFSE and R. ROSCH (GERMANY)

Degradation of wood-cell components by extracellular enzymes of Conlophora cerebelle

N. J. KING (U.K.) Lignolytic action of Schizophy/lum commune

L. JURASEK (CZECHOSLOVAKIA) Influence of extractives on cellulose and xylanase activities of Schizophyllum commune

R. SOPKO (CZECHOSLOVAKIA) The eff~t of carbon to nitrogen ratio of substrate on the growth, composition, cellulase production, and wood-destroying capa­city of Polys/ictus versicolor

M. P. LEVI and E. B. COWLING (U.S.A.) Growth of selected cellulolytic fungi on wood pulp

D. S. CHAHAL and D. GRAY (INDIA) Degradative activities on filamentous marine fungi

S. P. MEYERS (U.~.A.)

PART XI MARINE FOULING

Some factors affecting the underwater testing of wood-resisting antifouling paints

C. R. PEARSON (U.K.) The prevention of fouling by localized chlorine generation

T. LOVEGROVE and T. W. ROBINSON (deed.) (U.K.) Studies on possible mechanisms for the control of moulting and metamorphosis in barnacle larvae

A. M. MORTLOCK (U.K.) Marine boring and fouling organisms in open water off Monterey Bay, California

E. C. HARDERLIE (U.S.A.) Biological and physicochemical factors influencing the efficacy of antifouling paints

M.A. DOLGOPOLSKAYA and E. S. GUREVICH (U.S.S.R.)

PART XII STORED PRODUCIS MICROBIOLOGY

Effect of biocidal residues on wine making A. M. ADAMS (CANADA)

A new look at mouldy cocoa J. BROADBENT and J. 0. OYENIRAN (NIGERIA)

Biodeterioration of groundnut oil by Aspergilli R. J. TOMLTh.'S and R. J. TOWNSEND (U.K.)

Biodeterioration of harvested sugar cane R. H. TILBURY (U.K.)

MCthode d'apprCciation de Ia dCtCrioration biologique des grains par mesure du Temps Moyen de Germination

1. L. MULTON, P. LECOURS£ and A. GUILBOT (FRANCE)

Biodeterioration of Materials

Microbiological and Allied Aspects Edited by

A. HARRY WALTERS and JOHN J. ELPHICK

6! x !W x + 740 pages. 153 tables. 271 iUus. 1968. £12 lOs. Od.

This volume contains full reports of the 67 papers presented at the First International Biodeterioration Symposium, held at South­ampton in September 1968, and organized in association with the Society of Chemical Industry and the Organization for Economic Development and Cooperation to consider all aspects of biological action leading to the deterioration of materials, products or pro­cesses of economic importance.

ELSEVIER PUBLISHING CO. LIMITED

Ripple Road, Barking, Essex, England.

CONTENTS

Part I Fundamentals of Biodeterioration

Part ll Mechanisms of Biodeterioratlon

Part m Ecological Aspects of Biodeterioration

Part IV Testing for Biodeterioration Resistanee

Part V Control of Biodeterioration

Part VI Deterioration and Protection of Materials

Part Vll Hydrocarbon Microbiology and Metallic Corrosion

Part vm Ecological Aspects of Timber Decay

Part IX Biocides

Part X Enzymes and Physiology of Wood-destroying Organisms

Part XI Marine Fooling

Part Xll Stored Prodncts Microbiology

RADIATION PRESERVATION OF FOODS

Edited by Edward S. Josephson and J. Harry Frankfort

(American Chemical Society, Washington, 1967. Advances in Chemistry Series 65. viii + 184 pp. Price $7.00)

This volume performs a useful function in drawing together specialised information that would otherwise be lost in the very wide selection of journals publishing work on food irradiation. This collection of research papers, the proceedings of a conference, is not suitable for the reader requiring an introduction to the subject. It does not indicate whether commercial exploitation is imminent or wholesomeness problems overcome, subjects which one might expect to find discussed in a book with such a general title.

There are 6 papers on various aspects of dosimetry, sources, general engineering and design matters; 4 papers on the irradiation of beef; 3 on fruit or vegetables; 1 on fish and one paper on radiation effects in aqueous solutions of polyamino acids. Seven of the papers originated from or were written by scientists financially supported by the U.S. Army Natick Laboratories with a further three papers from other U.S. Government Laboratories.

The very impressive irradiation facilities at the Natick Laboratories are described in relation to the main Army effort to provide sterile meat for the armed services which needs no refrigeration "yet resembles fresh food when prepared." The U.S. Atomic Energy Commission program is also described and a paper on gamma irradiator design completes a trio of reports reiterating much material already published.

The main problem of using this technique to sterilise meat is the severe off-odour and off-flavour induced by radiation treatment. One paper describes the effect of different temperatures during irradiation on model amino acid and dipeptide systems. The production of carbonyl compounds and mercaptans was less at -196°C than at higher temperatures. Irradiation of beef steaks resulted in organoleptically satisfactory products if irradia­tion was performed at -196°C. Chemical findings and organoleptic results could not be correlated. Two other investigations, in which gas chromatographic techniques were used, showed that over 30 compounds of both protein and lipid origin could be isolated from the volatile material from irradiated meat. Amino acid destruction in beef was examined and cystine was found to be the most sensitive residue. The authors of this paper also describe

34

i

''I ' '

what they claim is a difference in amino acid destruction due to differences in the energy level of the radiation. The most interesting observation from the experiments on irradiated poly a-L glutamic acid is the optical inversion to D•glutamate particularly when oxygen was absent. The paper on radiation pasteurisation of fish and shellfish outlines suitable processing conditions for a number of species and also considers the question of survival and growth at various storage temperatures of resistant bacteria. A number of biochemical points are also considered including the interesting topic of enzyme irradiation by radiation. A good paper on surface treatment of spherical objects, the example taken being the orange, and a paper on biochemical changes in irradiated fruit and vegetables completes the volume. There is an adequate index.

This volume should be in the library for reference, but it does not add greatly to what is already known about the radiation preservation of foods.

G. Glew.

INSECf AND MARINE BORER DAMAGE TO TIMBER AND WOODWORK: RECOGNITION PREVENTION AND ERADICATION

J. D. Bletchley

(H.M.S.O., London, 1967. 87 pp. Price £1. 15. 0.)

This publication replaces an earlier Forest Products Research Laboratory bulletin which was called "Beetles Injurious to Timber and Furniture." It deals briefly with the biology of wood-boring insects and marine borers and describes the organisms and the damage that they cause. Emphasis is laid on the need to be able to recognise the cause of damage from the appearance of the infested wood, since the insects themselves are often absent or hard to find. A useful feature of the book is the inclusion of a table summarising for easy reference the diagnostic characters of damage caused by the commoner wood-boring insects and marine borers. It is also helpful to have, in an appendix, descriptions of insects likely to be mistaken for wood-boring species, such as plaster beetles, flour beetles and carpet beetles. Remedial treatments for existing infestations are given after each insect, and there is a whole chapter on protection of timber and woodwork, dealing mainly with treatments with chemical preservatives.

Another chapter deals briefly with the inspection of buildings with particular reference to churches; and a final chapter deals with the eradication of wood• boring insects by (1) fumigation with toxic gases, (2) heat, (3) liquid insecticides, and (4) insecticidal smokes.

The text is well arranged and clearly written. It is splendidly illustrated with quite excellent photographs both of the insects and of the damage that they cause.

The very large format (30 X 21 em.) is inconvenient for a book of reference which might have to be taken around by an inspector. This size is quite unnecessary as there are no full page photographs or plans. The layout also seems needlessly extravagant-on page 63, for instance, two small photos are tucked up in one comer, occupying only about 15% of the page. Possibly this is one reason for the very high price (35/-) which is some 23 times more than the 1940 bulletin.

W. P. K. Findlay.

INSECfS AND HYGIENE

J. R. Busvine

(Second Edition, Methuen & Co. Ltd., London, 1966, xi + 467 pp., 58 figs. Price £5)

Since its publication in 1951, Professor Busvine's work has been the standard textbook on insect pests of medical and domestic importance in Britain and similar temperate countries, a valuable source of reference to all those, in the Public Health and other fields, in any way concerned with insects and their more direct associations with man. A glance at the references, listed at the end of each chapter of this second edition, will show how thorough has been the task of revision; 50 per cent of those cited are post-1951, whilst for the chapter on chemical control measures, which has been completely re-written, the figure is 80 per cent.

The first chapter introduces the subject of insects as pests of hygiene, and includes some interesting, and amusing, historical notes. It is followed by three chapters dealing with the structure and classification of insects (and Arachnids), their anatomy and physiology, and their ecology.

The subject of control is introduced by a discussion of the organisation of preventive and control measures, incorporating useful summaries of courses of technical information and legislation in Britain relating to domestic insect pests. There follows a short account of mechanical, physical and biological control measures such as screening, hot air disinfestation, asphyxiants, dehydrants, electrocution and the more recent techniques of r-radiation and sterilisation procedures based on radioactivity and the use of chemosterilants.

35

The most noteworthy feature of the new edition is the revised chapter on chemical control measures the introduction to which includes a useful list of commercial designations of insecticides and their B.S.I. equivalents. Detailed information on pesticides is presented under the headings stomach poisons, contact poisons, fumigants, chemosterilants, repellents and attractants. Practical considerations follow, with a discussion of insecticide application in which details are given of equipment and formulations, and the chapter concludes with sections on insecticide resistance and toxic hazards of pesticides.

The remaining chapters, representing well over half of the book, are devoted to a detailed account of the characteristics, life histories and control of specific pests, arranged according to habit. Of particular interest to workers in the field of biodeterioration will be those chapters dealing with houseflies and blowflies, pests (insects and mites) offoodstuffs, insect pests in waste products, clothes moths and carpet beetles and wood boring beetles.

The book concludes with a "Biological Appendix", the larger part of which is composed of simple keys for the identification of many of the pests described in the foregoing chapters, both in the larval and adult stage.

A book as wide in its scope and wealth of detail as this would be unique if it were completely free of errors, and some have been noted, albeit mostly of a minor nature as, for example, "carbonate", not carbamate, with reference to the secondary constituent of the fumigant tablets from which phosphine is liberated (p. 110), "mer­captor" for mercator (p. 310), "Epherstia and Anagaster" for Ephestia and Anagasta (p. 321), and (uncorrected from the first edition) "Antheribidae" for Anthribidae (p. 455).

In the introductory remarks on fumigants (p. 108) the reader is confused by the statement that "they do not normally leave residues and therefore give no protection from re,infestation". The latter part of this statement indicates, correctly, that a fumigation treatment will impart no residual pest control effect, but it is well known that it may leave residues as, for example, the inorganic bromide detectable in stored foodstuffs following fumiga­tion with methyl bromide.

In the chapter on pests of foodstuffs, information on the Tropical Warehouse Moth, Cadra cautella is wrongly inserted under Oecophoridae (p. 321), although the species is first mentioned, correctly, as a member of the family Phycitidae (p. 319).

Additional couplets have been inserted at the beginning of the key to adult beetles (p. 454) to include the Cerambycid, Hylotrupes and the Curculionids, Euophryum and Pentarthrum, and it is unfortunate that the author has failed to amend three of the couplets which follow; for example, couplet 5 should lead to couplets 6 and 8 (not 3 and 5), the first part of couplet 13, Ptinidae, to couplet 14 (not II) and the second part of couplet 28 to couplet 30 (not 27).

These are not serious criticisms, however, and do not detract from the value of a book which is both highly informative and well produced; it is well worthy of a place ou the shelves of any reference library.

P. F. Prevett.

36

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69/1- GRAY, T. R. G. & BAXBY, P. 6721

Transactions British Mycological Society, 51 (2): 293-309, (1968).

Chitin decomposition of soil. n. The ecology of chitinoclastic micro-organisms in forest soil. [Fungi. Bacteria. Actinomycetes.]

69/1· ORL!TA, A. 6722

LEATHER

Proceedings International Biodeterloration Symposium, 1st, Southampton, 9th-14th Sept., 1968: 297-301, (1968).

Biodcterioration in the leather industry. [Fungi.]

KERATIN AND ClDT1N (Coot), LEATHER, LIGNIN, METALS

69/1- ANDERSEN, J. E.; HERWIG, G. L. & 6n9 MOFFITT, R. B.

Australian Mining, 35-39, (IS April 1966).

Heap leaching at Rum Jungle. [Copper. Thiobacil/us.l

69/1· LOBL, M. 6730

Australasian Corrosion Engineering, 12 (6): 3-12, (1968).

The choice of materials for gas mains and modifications of existing systems. [Soil. Corrosion. Resistance.]

69/1- IYERSON, W. P. 6731

Nature, 217 (5135): 1265-1267, (1968).

Corrosion of iron and formation of iron phosphide by Desu/fovibrio desu/furlcans.

HAVE YOU PLACED YOUR ORDER FOR

IBBRISt (INTERNATIONAL BIODETERIORATION BULLETIN

REFERENCE INDEX SUPPLEMENT)

IBBRIS IS A BIBLIOGRAPHIC JOURNAL FOR THE DISSEMINATION OF REFERENCES TO MATERIAL PUBLISHED ON ALL ASPECTS OF

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COMBINED ANNUAL SUBSCRIPTION FOR THE INTERNATIONAL BIODETERIORATION BULLETIN AND IBBRIS : £6 ($15).

Tappi, 51 (7): 298-300, (1968). Improved ball milling in the isolation of milled wood lignin. [Grinding. Technique.]

METALS

69/1- GOLOMSIK, A. I. & IVANOV, V. I. 6727

Mikrobiologiya, 34 (3): 465468, (1965).

Adaptation of Thiobacillus ferroxidans to Increased concentrations of hydrogen and iron Ions. (In Russian; English summary.]

69/1- ANON. 6728

Newsletter Ontario Research Foundation, 9 (7): I p. (1966).

Corrosion engineering. [Metal.]

Metal-organic acid corrosion and some mechanisms associated with these corrosion processes. [Metal.]

69/1- GUPTA, S. K.; SANYAL, B. & NANDA, J. N. 6736

LabdevJ. Science Technology, 6-A (1): 1-13, (1968).

Underground corrosion: Pt. I- Factors affecting corrosion and methods of assessment. [Metals. Chemical deterioration. Bacteria. Testing.]

69/1- GUPTA, S. K.; SANYAL, B. & NANDA, J. N. 6737

LabdevJ. Science Technology, 6-A (2): 51-59, (1968).

Underground corrosion: Pt. n - Methods or protection.

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Published by the Biodeterioration Information Centre. COST PRICE C1 Printed by Suttons (Printers) Ltd.

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