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Chapter Title Production of Biosurfactants Using Eco-friendly MicroorganismsCopyright Year 2015Copyright Holder Springer IndiaAuthor Family Name Uzoigwe

ParticleGiven Name ChibuzoSuffixDivision School of Science and EngineeringOrganization Teesside UniversityAddress Middlesbrough, TS1 3BA, UK

Author Family Name EnnisParticleGiven Name Christopher J.SuffixDivision School of Science and EngineeringOrganization Teesside UniversityAddress Middlesbrough, TS1 3BA, UK

Corresponding Author Family Name RahmanParticleGiven Name Pattanathu K. S. M.SuffixDivision School of Science and EngineeringOrganization Teesside UniversityAddress Middlesbrough, TS1 3BA, UKEmail p.rahman@tees.ac.uk

Abstract Pathogenicity of biosurfactant-producing microorganisms is currentlyraising some health, safety and environmental concerns. As a result,the industrial-scale production and application of biosurfactants aspotential alternatives to the synthetic one is still an unachieved task.The production of biosurfactants using nonpathogenic/recombinantstrains requires more attention and investigation for some advantagesthat includes the discovery of non-toxic biosurfactants suitable forall industrial applications, identifying new biosurfactant congenerswith better inherent surface-active properties compared to that frompathogens and synthetic ones and the synthesis of biosurfactant withoutcomplex metabolic regulations. Although a number of nonpathogenic/recombinant, eco-friendly biosurfactant-producing strains have beendocumented, there is need for more research in this area focusingespecially on improved biosurfactant production by these strains using

optimisation processes and the discovery of new nonpathogenic/recombinant strain using molecular techniques for future sustainability.

Keywords(separated by “-”)

Bioremediation - Biosurfactants - Recombinant strains - Rhamnolipids

P. Thangavel and G. Sridevi (eds.), Environmental Sustainability: Role of Green Technologies,DOI 10.1007/978-81-322-2056-5_11, © Springer India 2015

Abstract

Pathogenicity of biosurfactant- producing microorganisms is currently raising some health, safety and environmental concerns. As a result, the industrial-scale production and application of biosurfactants as potential alternatives to the synthetic one is still an unachieved task. The production of biosurfactants using nonpathogenic/recombinant strains requires more attention and investigation for some advantages that includes the discov-ery of non-toxic biosurfactants suitable for all industrial applications, identifying new biosurfactant congeners with better inherent surface-active properties compared to that from pathogens and synthetic ones and the synthesis of biosurfactant without complex metabolic regulations. Although a number of nonpathogenic/recombinant, eco-friendly biosurfactant- producing strains have been documented, there is need for more research in this area focusing especially on improved biosurfactant production by these strains using optimisation processes and the discovery of new nonpathogenic/recombinant strain using molecular techniques for future sustainability.

Keywords

Bioremediation • Biosurfactants • Recombinant strains • Rhamnolipids

C. Uzoigwe • C.J. Ennis • P.K.S.M. Rahman (*) School of Science and Engineering, Teesside University, Middlesbrough TS1 3BA, UKe-mail: p.rahman@tees.ac.uk

Production of Biosurfactants Using Eco-friendly Microorganisms

Chibuzo Uzoigwe, Christopher J. Ennis, and Pattanathu K.S.M. Rahman

1 Introduction

Biosurfactants refer to surfactants from micro-bial origin and can be synthesised by several identified microorganisms including bacteria, yeast

and fungi. Originally, majority of the surfactants used in the industries today are petrochemical based, and these surfactants are not only par-tially biodegradable but are also toxic to living organisms and have contributed to a wide range of environmental hazards. In addition, the pro-duction of these petrochemical-based surfactants contributes to the depletion of the world’s non- renewable petrochemical resources. It has been reported that the worldwide production of

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synthetic surfactants is over 15 million tons per year (Van-Bogaert et al. 2007) that are employed in different industrial sectors ranging from food processing, pharmaceutical, cosmetics, deter-gent production, environmental cleanup (biore-mediation) and enhanced oil recovery. According to Reznik et al. (2010), the worldwide produc-tion of synthetic surfactants per annum was 13 million tons in 2008, increased by 2 % in 2009 resulting to annual turnover of US$ 2,433 billion. The market was then expected to experience a continuous growth by 28 % from 2009 to 2012 and thereafter increase approximately by 3.5–4 %. However, biosurfactants have been reported by many researchers to have a variety of advantages over the petrochemical-based or synthetic sur-factants. They display excellent surface activity and emulsification properties with very low toxicity and higher biodegradability features. They have also been found to be very effective at low concentrations and over a wide range of environmental conditions such as pH, temperature, salinity, alkalinity and acidity. Other important characteristics of these biomolecules include better environmental compatibility, lower critical micelle concentration, higher selectivity, specific activity and ability to be synthesised from renew-able low- cost resources (Desai and Banat 1997; Oliveira et al. 2009; Rahman and Gakpe 2008).

These biosurfactants due to their amphiphilic properties have found potential application in an extremely wide variety of industrial process involving emulsification, foaming, detergency, wetting, dispersing or solubilisation. In addition, biosurfactants are currently being used as anti-bacterial, antifungal, antiviral, antioxidant, mois-turisers and antiradical and stabilising agents in the production of various industries, products ranging from cosmetics, food, pharmaceutical, agriculture and detergents. Their ability to stimu-late dermal fibroblast metabolism and support healthy skin physiology has also put them on the front line as potential raw material for cosmetics such as deodorants, facial cosmetics, lotions, eye shadow, skin smoothing and anti-wrinkle and anti-ageing products (Rosenberg and Ron 1999; Banat et al. 2000; Rahman et al. 2002).

The commercial viability of biosurfactants as alternatives to the synthetic surfactants has been greatly hindered due to limiting technical and economic factors including high substrate cost (Mukherjee et al. 2006), low product yield (Maneerat 2005; Thavasi et al. 2011b), product mixtures resulting in high-cost downstream recovery/purification processes (Heyd et al. 2008) and the type of producing strains (Reiling et al. 1986). Most biosurfactant-producing organ-isms are pathogenic and difficult to handle in large-scale industrial processes (Gunther et al. 2005; Toribio et al. 2010). In this review, after a discussion of the pathogenicity of biosurfactant, producers focus on the state of the art of production of biosurfactants from nonpathogenic eco- friendly organisms and on the heterologous production by recombinant strains.

2 Biosurfactant Production Using Pathogenic Organisms and Health and Safety Issues

The development of biosurfactant production in nonpathogenic organisms is a current challenge that is receiving increased attention in order to avoid pathogenicity and complex metabolic regu-lations (Dusane et al. 2010) especially in rham-nolipid synthesis by Pseudomonas aeruginosa and to screen for novel product spectra (Müller et al. 2012). Application of crude biosurfactants from pathogens in industrial and environmental applications is largely unacceptable especially in the cosmetics, health and food sectors due to the potential presence of toxins and pigments (Nicas and Iglewski 1985).

2.1 Rhamnolipids

Rhamnolipids are widely studied glycolipid biosurfactants synthesised in large quantities by different strains of P. aeruginosa. As biosurfac-tants, rhamnolipids play an important role for the producing organism, displaying useful physico- chemical, physiological (Zhong et al. 2007)

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and antimicrobial functions on other living systems (Bergstrom et al. 1946; Abalos et al. 2001). Excellent emulsifying properties relative to syn-thetic surfactants make rhamnolipids viable alter-natives due to their efficacy at low concentrations and their inherent biodegradability (Ron and Rosenberg 2002; Calvo et al. 2009; Rahman et al. 2003), for example, the bioremediation of hydrocarbon- polluted sites (Thavasi et al. 2011a; Jorfi et al. 2013) and in enhanced oil recovery (Amani et al. 2013). However, the industrial- scale application of P. aeruginosa strains for rhamnolipid production is an unrealistic task: this organism is an opportunistic human pathogen (Rahman et al. 2010) and is responsible for infec-tious diseases in immune-compromised individuals (Goethals et al. 2001). Addressing these safety issues renders that P. aeruginosa-derived biosur-factant is uneconomical (Ochsner et al. 1995; Tuleva et al. 2002) and unsafe for industrial processes.

The cultivation of P. aeruginosa, a Gram- negative bacterium belonging to the taxonomi-cal class of Gammaproteobacteria and the family Pseudomonadaceae, has been well stud-ied, and the genome of strain PAO1 has been fully sequenced and annotated. The organism is found in various habitats including water, soil, plants and air, is resistant to a variety of antibi-otics (Tummler et al. 1991) and is the main causative organism for cystic fibrosis and noso-comial infections. The pathogenicity of P. aeru-ginosa in cystic fibrosis was confirmed by Kownatzi et al. (1987) who discovered rhamno-lipids of up to 8 μl/ml in the sputum of P. aeru-ginosa-colonised cystic fibrosis patients. Read et al. (1992) also showed the presence of 65 μl/ml rhamnolipid in the secretions of a lung removed from a cystic fibrosis patient. The cyto-toxic and haemolytic effects of crude rhamno-lipids from other rhamnolipid producers have been demonstrated by researchers (Häussler et al. 1998, 2003; Rahman et al. 2010). Rhamnolipids have been shown to be heat-sta-ble haemolysins having haemolytic activity on various erythrocyte species (Fujita et al. 1998; Johnson and Boese-Marrazzo 1980) and

cytotoxic at high concentration to immune cells (Bjarnsholt et al. 2005; Jensen et al. 2007).

Rhamnolipids from P. aeruginosa stimulate the release of allergy and inflammatory media-tors from the mast cells such as histamine, sero-tonin and 12-hydroxyeicosatetraenoic acid (Bergmann et al. 1989; McClure and Schiller 1992; König et al. 1992; Cosson et al. 2002; Andrä et al. 2006). Furthermore, rhamnolipids have been associated with several dysfunctions in the lungs and the entire respiratory tract. These include inhibition of ciliary function, damage to bronchial epithelium, alteration of respiratory epithelial ion movement and induction of the release of mucus conjugates from human bron-chial mucosa, and very recently it has been reported that rhamnolipid synthesis is an impor-tant prerequisite for the invasion of P. aeruginosa into human respiratory epithelial cells (Stutts et al. 1986; Graham et al. 1993; Fung et al. 1995; Zulianello et al. 2006). P. aeruginosa has been classified as biosafety level 2 organism due to the health and safety issues associated with the organism as well as the cytotoxic properties of their rhamnolipid species.

These safety concerns inhibit the economic viability of large-scale rhamnolipid production from P. aeruginosa. Such viability is further compromised by the involvement of complex quorum sensing and transcriptional mechanisms (Soberón-Chávez et al. 2005). Furthermore, the purification and treatment of the rhamnolipid yield from P. aeruginosa are also costly at the industrial scale, and it is important to note that rhamnolipids produced from P. aeruginosa fer-mentation cannot be considered as safe raw mate-rials in the production of food, pharmaceutical and cosmetics products. Thus there is need to explore for new nonpathogenic natural rhamno-lipid producers. A survey of biosurfactants pro-duced by pathogenic strains is presented in Table 1 together with their pathogenesis in humans, plants and animals.

Rhamnolipids are also produced by Burkholderia species; some of these organisms such as B. cepacia have been identified as human pathogens. This organism capable of producing a

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Table 1 Biosurfactant production by pathogenic bacterial strains

Biosurfactants Pathogenic producers Pathogenicity References

Rhamnolipids Pseudomonas aeruginosa

Cystic fibrosis, respiratory infections, multidrug resistant

Thavasi et al. (2011b), Jorfi et al. (2014), Kownatzi et al. (1987)

Burkholderia cepacia Lung infection, pneumonia St Denis et al. (2007), Yalçin and Ergene (2010)

Burkholderia pseudomallei

Melioidosis Andrea et al. (2008), Howe et al. (2006)

Burkholderia plantarii Fire blight disease of apple and pear trees

Hörmann et al. (2010), Mitchell and Teh (2005)

Burkholderia glumae Rot of rice grains and seedlings

Urakami et al. (1994), Costa et al. (2011)

Renibacterium salmoninarum

Bacterial kidney disease of salmonid fish

Christova et al. (2004), Wiens et al. (2008)

Glycolipids Pantoae agglomerans Bacteraemia, wound infection, arthritis, infection of soft tissues bones and joints in children

Vasileva-Tonkova and Geshava (2007), Jacobucci et al. (2009), Koo et al. (2006)

Nocardia otitidiscaviarum

Pulmonary nocardiosis, brain abscess, actinomycetoma

Vyas and Dave (2011), Pelaez et al. (2009), Chi et al. (2013)

Alcaligenes faecalis Post-operative endophthalmitis, peritonitis

Kaliaperumal et al. (2006), Kahveci et al. (2011), Bharali et al. (2011)

Trehalose mycolates Acinetobacter calcoaceticus IMV B-7241

Urinary tract infections, respiratory tract infections, post-operative infections

Pirog et al. (2013), Pal and Kale (1981)

Phospholipids Klebsiella pneumoniae Haemorrhage/necrosis, upper and lower respiratory tract infections, osteomyelitis, UTI, diarrhoea, wound infection, meningitis, bacteraemia, septicaemia, ankylosing spondylitis

Jamal et al. (2012), Rashid and Ebringer (2007), Ryan and Ray (2004), Limbago et al. (2012)

Lipopeptides Serratia marcescens Urinary tract infections, nosocomial bacteraemia, meningitis, endocarditis

Ibrahim et al. (2013), Anyanwu et al. (2010), Körner et al. (1994)

Inquilinus limosus KB3

Cystic fibrosis, multidrug- resistant lung infections

Saimmai et al. (2013), Wellinghausen et al. (2005), Hayes et al. (2009)

Heteropolysaccharides Cronobacter sakazakii Bacteraemia, meningitis, necrosis, enterocolitis, contamination of infant formula

Lai (2001), Jain et al. (2012), CDC (2002)

biosurfactant exhibiting a surface tension value of 45.7 mN m−1 (Yalçin and Ergene 2010) has been associated with lung infections and pneumonia in humans of all ages (St Denis et al. 2007). Similarly, B. pseudomallei, a biosurfactant producer (Howe et al. 2006), is a facultative intracellular pathogen, although the mechanism of its intracellu-lar survival is yet unknown. This pathogen is the

causative agent of melioidosis, an infectious disease endemic to Southeast Asia, northern Australia and tropical and subtropical regions (Andrea et al. 2008). The di- rhamnolipids from B. pseudomallei have been found to exhibit serious cytotoxic effects on macrophages non- phagocytic and phagocytic cell lines (Sierra 1960; Kharazmi et al. 1989; Johnson and Boese- Marrazzo 1980;

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Fujita et al. 1988). Di-rhamnolipids have also been reported to be cytolytic to human mono-cyte-derived macrophages and can inhibit the phagocytic response of macrophages even at low concentration.

Burkholderia plantarii DSM 9509 has been demonstrated to be the most prominent rhamno-lipid producer. According to Hörmann et al. (2010) and Walter (2009), B. plantarii DSM 9509 produced Rha2-C14-C14 congeners that reduced the surface tension of water to 29.4 mN m−1 with critical micelle concentrations (CMC) between 15 and 20 mg L−1. The maximum rham-nolipid concentration during 0.5 L bioreactor cul-tivation was 45.75 mg L−1. However, this organism is a plant pathogen responsible for the fire blight disease of apple and pear trees, and the di-rhamnolipid from B. plantarii is an endotoxin (Mitchell and Teh 2005). Costa et al. (2011) also showed rhamnolipid concentration of 1 g L−1 in B. glumae AU6208 at 34 °C, 2 % canola oil and 100 mM urea, but this organism is toxic to rice grain and seedlings.

Renibacterium salmoninarum is a diplobacil-lus fastidious bacterium identified as potent bio-surfactant producer on n-hexadecane as a carbon source (Christova et al. 2004). It is also interest-ing to know that this bacterium produces the two typical rhamnolipid as in P. aeruginosa and has the potential of being useful in natural degrada-tion of hydrophobic pollutants due to its high cell hydrophobicity. Despite these promising charac-teristics, this organism has raised a significant ecological concern. It causes a haemorrhagic infection known as bacterial kidney infection (BKD) or salmonid kidney disease in young sal-monid fish (Wiens et al. 2008).

2.2 Glycolipids and Trehalose Mycolates

Glycolipid production by other known pathogens has been reported. The Antarctic facultative anaerobe Pantoea agglomerans is a biosurfactant producer with hydrocarbon compounds (hexane, kerosene and paraffin) as growth substrates (Vasileva-Tonkova and Gesheva 2007; Jacobucci

et al. 2009). Pantoea sp. has also been reported as producers of high levels of exopolysaccharides with maximum production of 21 g L−1 in 24 h on glucose fructose and sucrose. However, Pantoea sp. have recently been consistently linked with infections in humans (wound, blood, soft tissue, bone and urinary tract infections) and plants (Da Baere et al. 2004; Fullerton et al. 2007; Kratz et al. 2003). These organisms have also been associated with bacteraemia outbreaks in many patients through their contact with contaminated cotton pledgets (Koo et al. 2006; Silvi et al. 2013).

Production of glycolipid biosurfactant has been reported for Nocardia otitidiscaviarum, a marine strain. The biosurfactant possessed increased cell hydrophobicity, making it very potent for bioremediation of oil-polluted sites (Vyas and Dave 2011). Recently, these bacterial species have been identified as causative agents in a couple of clinical infections ranging from pulmonary nocardiosis, brain abscess and actino-mycetoma (Pelaez et al. 2009; Chi et al. 2013).

Alcaligenes faecalis has been reported by Bharali et al. (2011) as a producer of biosurfac-tant exhibiting excellent surface activity using different hydrocarbon substrates. However, A. faecalis is a known pathogen infecting human and domesticated birds such as chickens and tur-keys (Simmons et al. 1981). Kaliaperumal et al. (2006) reported A. faecalis as the causative agent in post-operative endophthalmitis in human eye resulting in symptoms such as swelling of the eyelid, redness and permanent loss of vision. In addition, Kahveci et al. (2011) have reported a link between the developments of peritonitis to contamination of catheters by A. faecalis. The pathogenic mechanism of this microbe is largely unknown.

Rosenberg et al. (1989) identified Acinetobacter calcoaceticus A2 as a producer of an extracellu-lar anionic surfactant referred to as biodispersan or emulsan which is a high molecular weight bio-surfactant. Pirog et al. (2009) have also reported the production of low molecular weight biosur-factant by A. calcoaceticus IMV B-7241 which was confirmed to be trehalose mycolates by enzymatic studies. A. calcoaceticus has been described as a commensal in humans but is also

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responsible for many clinical infections as an opportunistic pathogen. These infections include urinary tract infection, pneumonia, respiratory tract infection and post-operative infections (Pal and Kale 1981).

2.3 Phospholipids and Lipopeptides

Biosurfactant production by a prominent member of the Klebsiella genus known as Klebsiella pneumoniae has been identified. According to Jamal et al. (2012), Klebsiella pneumoniae WMF02 showed increased biosurfactant produc-tion after medium optimisation with a maximum yield of 85 g L−1 and surface tension reduction of 25.70 mN m−1 compared to the non-optimised medium (36.2 mN m−1). This organism has shown the promising potential of a good biosurfactant producer, but its application will involve certain health and safety risks. K. pneumoniae is a sig-nificant human pathogen causing different destructive effects to the human upper and lower respiratory tracts if inhaled which includes pneu-monia and bronchitis. Other notable infections caused by this organism include diarrhoea, wound infections, osteomyelitis, meningitis, bac-teraemia and septicaemia (Ryan and Ray 2004). Recently, these bacterial strains have been reported as resistant to antibiotics especially car-bapenem antibiotics (Limbago et al. 2012). They have also been associated with a chronic inflam-matory spinal and large joint arthritic condition known as ankylosing spondylitis (AS) affecting young-aged males (Rashid and Ebringer 2007).

Serratia marcescens is a multidrug-resistant pathogen causing infections in different hosts ranging from plants, animals and humans. This bacterium produces a lipopeptide biosurfactant known as serrawettin (Dusane et al. 2011). The biosurfactant is very potent and has been reported in literature to reduce the surface tension of water from 72 to 37 mN m−1, emulsifying kerosene and diesel with a maximum emulsion index of 72 % and 40 %, respectively (Wei et al. 2004). Ferraz et al. (2002) also reported biosurfactant produc-tion by S. marcescens strains. The biosurfactant

reduced the surface tension of the culture medium from 64.54 to 29.57 mN m−1, while the crude bio-surfactant reduced the surface tension of water from 72 to 28.70 mN m−1. However, this bacte-rium cannot stand the chance of being used for industrial-scale production of biosurfactant due to its pathogenicity. Most importantly, serrawettin biosurfactant is a virulence factor, and S. marcescens strains have been linked with a of number infections including nosocomial infections bac-teraemia, urinary tract infections, meningitis and endocarditis (Anyanwu et al. 2010; Körner et al. 1994). According to a report by the Centers for Disease Control in the USA, S. marcescens was confirmed as the main causative organism in the Alabama hospital outbreaks that happened in 2011 affecting 19 patients with 10 deaths.

Saimmai et al. (2013) identified a Gram- negative bacterium Inquilinus limosus KB3 capable of producing lipopeptide biosurfactant using palm oil cake as a carbon source. The bio-surfactant reduced the surface tension of water from 72 to 25.5 mN m−1 with a maximum yield of 5.13 g L−1 and CMC at 9 mg L−1. The genus Inquilinus was first defined in 2002 based on the molecular analysis of 51 unknown cystic fibrosis isolates. This group of organisms is unrelated to P. aeruginosa and B. cepacia. Inquilinus limosus has been reported as a multidrug-resistant pathogen and has been isolated from the lungs of cystic fibrosis patients (Wellinghausen et al. 2005; Hayes et al. 2009).

2.4 Heteropolysaccharides

Jain et al. (2012) reported the production of a het-eropolysaccharide biosurfactant by an alkaliphi-lic bacterium, Cronobacter sakazakii, formerly known as Enterobacter sakazakii. The biosurfac-tant comprised of total sugars (733 %), reducing sugars (1,464 %), protein (119 %), uronic acid (1,598 %) and sulphate (6,015 %). The monosac-charide moieties in this biosurfactant were revealed by GC-MS as glucose (14 %), mannose (24 %), galactose (14 %), xylose (20 %) and arabinose (19 %). The extracted biosurfactant from this bacterium efficiently emulsified aliphatic

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and aromatic hydrocarbons forming stable emul-sions in the presence of xylene, cyclohexane, cyclooctane, toluene, carbon tetrachloride, dichloromethane, cottonseed, jojoba and ground-nut oil at 1 mg mL−1. The inherent properties of the biosurfactant make it a potential candidate for bioremediation of oil and hydrocarbons. However, Cronobacter sakazakii is a Gram- negative pathogenic bacterium (Lai 2001), reported as the cause of meningitis bacteraemia, necrosis and enterocolitis in infants. Infections have been associated with the use of powdered infant formula contaminated with the bacterium (Bowen and Braden 2006; CDC 2002).

The industrial application of pathogenic bio-surfactant producers is clearly problematic based on the pathogenic effects of the organisms and their products on humans and animals. Additionally, some of these pathogens exhibit multidrug resistance and have recorded high mortality rates from their associated diseases. Therefore, they are now considered as potential biological warfare agents and as such are not potential biological models for industrial bio-technological processes (Walter 2009). For this combination of security and health reasons, there is a need to develop industrial processes based on nonpathogenic biosurfactant-producing strains.

3 Biosurfactant Production Using Nonpathogenic Organisms

Recently, due to the health and safety issues asso-ciated with some biosurfactant-producing strains, research towards identifying new nonpathogenic producers and biotechnological production of biosurfactants using recombinant/mutant strains has been given more attention. The advantages of using nonpathogenic organisms may include production of biosurfactants with various con-gener species, including the possibility of bio-surfactants with less or no cytotoxic effects on living cells, and disconnection of their synthetic pathways from complex mechanisms such as quorum sensing in rhamnolipid synthesis.

Nonpathogenic natural producer strains and their biosurfactant types identified to date have been reported (Table 2).

3.1 Rhamnolipids

Novel natural producers of rhamnolipids identi-fied as P. clemancea nov. and P. teessidea nov. have been reported by Rahman et al. (2010). Rhamnolipid production can be achieved with Pseudomonas sp. other than P. aeruginosa. Pseudomonas fluorescens is a nonpathogenic Gram-negative, rod-shaped bacterium that has been found to produce biosurfactants as well as useful enzymes (cellulase, pectinase), self- defence factors (hydrogen cyanide), siderophores (pyochelin, pyoverdine), antibiotics (pyrrolnitrin, pyoluteorin) and 2,4-diacetylphloroglucinol, a molecule that can break down plant-derived car-bohydrates, enhance host immune mechanisms and inhibit phytopathogens and bacteriophages (Stover et al. 2000; Paulsen et al. 2005). This organism has been reported as a degrader of cer-tain environmental pollutants such as styrene, TNT and polycyclic aromatic hydrocarbons and as a result has been employed in many bioreme-diation processes.

The production of a thermostable rhamnolipid biosurfactant with excellent foaming and emulsi-fying stability by P. fluorescens was reported by Abouseoud et al. (2007). The biosurfactant was stable at 100 °C and retained its positive effect on surface tension (34–30 mN m−1) even at high pH values. Stoimenova et al. (2009) isolated from industrial wastewater P. fluorescens HW-6 capa-ble of producing rhamnolipid biosurfactants at relatively high levels on various carbon substrates including hexadecane, vegetable oil, mineral oil and glycerol. The culture supernatant of the strain exhibited a reduction in surface tension to 28.4 mN m−1. Vasileva-Tonkova et al. (2006) also reported production of rhamnolipid biosurfactant by P. fluorescens HW-6 at concentrations of 14–20 g L−1 on hexadecane and interfacial tension of 35 mN m−1, possessing a low critical micelle concentration value of 20 mg L−1. Recently, a

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Table 2 Biosurfactant production using nonpathogenic bacteria

Biosurfactants Microbial strainsPhysico-chemical characteristics References

Rhamnolipids Pseudomonas clemancea nov. Mesophilic Rahman et al. (2010)Pseudomonas teessidea nov. Mesophilic Rahman et al. (2010)Pseudomonas fluorescens Mesophilic Abouseoud et al. (2007),

Vasileva-Tonkova et al. (2006)

Pseudomonas chlororaphis Mesophilic Gunther et al. (2005)Pseudomonas putida BD2 Mesophilic Janek et al. (2013)Burkholderia thailandensis Mesophilic Dubeau et al. (2009)Enterobacter asburiae Mesophilic Hošaková et al. (2013)Thermus aquaticus Thermophilic Řezanka et al. (2011)Meiothermus ruber Thermophilic Řezanka et al. (2011)Enterobacter hormaechei PTCC 1799

Mesophilic Rabiei et al. (2013)

Tetragenococcus koreensis Halophilic Lee et al. (2005)Pseudoxanthomonas sp. PNK-04 Mesophilic Nayak et al. (2009)

Glycolipids Streptococcus thermophilus A Thermophilic Rodrigues et al. (2006a, b)Lactococcus lactis 53 L. acidophilus

Mesophilic Rodrigues et al. (2006a, b), Tahmourespour et al. (2011)

Lactobacillus coryniformis sp. torquens CECT 25600

Mesophilic Gudiña et al. (2011)

Lactobacillus paracasei sp. paracasei A20

Mesophilic Gudiña et al. (2011)

L. plantarum A14 Mesophilic Gudiña et al. (2011)Leuconostoc mesenteroides Mesophilic Gudiña et al. (2011)Lactobacillus delbrueckii Mesophilic Thavasi et al. (2011a)

Trehalose lipids Rhodococcus erythropolis IMV Ac-5017, Rhodococcus sp.

Mesophilic Pirog et al. (2013), Mutalik et al. (2008)

R. erythropolis ATCC 4277 Mesophilic Pacheco et al. (2010)R. ruber Z25 Mesophilic Zheng et al. (2009)

Lipopeptides/phospholipids Bacillus subtilis DM-03, Bacillus subtilis DM-04

Mesophilic Das and Murkherjee (2007)

B. subtilis PT2 Mesophilic Pornsunthorntawee et al. (2008)

B. subtilis LB5a Mesophilic Nitschke and Pastore (2006)

B. subtilis Mesophilic Cooper et al. (1981)B. lentus, B. firmus Mesophilic Ibrahim et al. (2013)Bacillus licheniformis Biria et al. (2010)Selenomonas ruminantium Mesophilic Saimmai et al. (2013)Brevibacterium aureum MSA13 Mesophilic Kiran et al. (2010)Corynebacterium kutscheri Mesophilic Thavasi et al. (2007)Corynebacterium alkanolyticum ATCC 21511

Mesophilic Crosman et al. (2002)

Heteropolysaccharides Halomona sp. BS4 Halophilic Donio et al. (2013)Halomonas sp. TG89 Halophilic Gutierrez et al. (2012)Halomona eurihalina Halophilic Calvo et al. (2002)

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rhamnolipid exhibiting high antimicrobial activities on both Gram-positive and Gram-negative pathogenic strains – Listeria monocytogenes, Staphylococcus aureus, methicillin- resistant S. aureus, E. coli, Salmonella typhimurium and Candida albicans – has been reported to be pro-duced from Pseudomonas fluorescens MFS03 (Govindammal and Parthasarathi 2013). The bio-surfactant was effective as a surface and emulsi-fying agent and could have potential applications in the bioremediation of hydrocarbon-polluted sites. Rhamnolipid production was also reported for nonpathogenic P. chlororaphis (Gunther et al. 2005) and P. putida BD2 (Janek et al. 2013).

Dubeau et al. (2009) reported production of 0.4–1.5 g L−1 rhamnolipid by Burkholderia thai-landensis at 34 °C with 4 % glycerol or canola oil in nutrient broth. B. thailandensis is a Gram- negative, mesophilic bacterium closely related to B. pseudomallei but rarely causes infections in humans or animals (Wuthiekanun et al. 1996; Smith et al. 1997; Lertpatanasuwan et al. 1999). The lethal inoculum size for B. thailandensis is approximately 1,000 times higher than that for B. pseudomallei (Joost Wiersinga et al. 2008). This organism does not require biosafety level 3 con-ditions and has no restriction on the use of antibi-otics or resistance markers for its genetic manipulation. The organism is not considered as a biosecurity threat and therefore is a potential industrial tool (Haraga et al. 2008; Glass et al. 2006). Recently, Hošaková et al. (2013) identi-fied Enterobacter asburiae as nonpathogenic rhamnolipid producers. Rezanka et al. (2011) reported on three novel rhamnolipid-producing organisms and were identified as Thermus sp., Thermus aquaticus and Meiothermus ruber. These organisms have been categorised as bio-safety level 1 organisms and are not pathogenic to humans. Pantazaki et al. (2010) have reported the simultaneous production of polyhydroxyal-kanoates (PHAs) and rhamnolipids by a non-pathogenic thermophilic bacterium Thermus thermophilus HB8 (DSM 579) cultivated in min-eral salt medium at 75 °C using glucose and sodium gluconate as sole carbon sources. Other new nonpathogenic rhamnolipid producers include Enterobacter hormaechei PTCC 1799

(Rabiei et al. 2013), Tetragenococcus koreensis (Lee et al. 2005) and Pseudoxanthomonas sp. (Nayak et al. 2009).

3.2 Glycolipids

The Streptococcus thermophilus bacterium is used widely in the dairy industries for the produc-tion of yogurt and cheese and is considered as beneficial to health since it aids digestion of dairy products in lactose-intolerant individuals (Kiliç et al. 1996; Hutkins 2002; Taylor and Mitchell 2007). According to Busscher et al. (1997), a bio-surfactant released from S. thermophilus was used in the control of fouling of heat-exchanger plates in pasteurisers because it inhibited the colonisa-tion of other thermophilic and pathogenic strains of Streptococcus responsible for fouling. Two probiotic bacteria Lactococcus lactis 53 and S. thermophilus A have been identified as produc-ers of cell-bound biosurfactants at the stationary growth phase in the presence of lactose and cheese whey as carbon substrates (Rodrigues et al. 2006a, b). A protein-containing biosurfactant from Lactobacillus acidophilus has also been demon-strated to reduce the adhesion and biofilm forma-tion of Streptococcus mutans on glass slides (Tahmourespour et al. 2011), indicating that the treatment of teeth with this biosurfactant may be an alternative dental control for biofilm develop-ment and adhesion of the pathogens on teeth.

Similarly, Gudiña et al. (2011) investigated the production of cell-bound and excreted biosur-factant by three lactobacilli strains and Leuconostoc mesenteroides strains. The lactoba-cilli strains were L. coryniformis sp. torquens CECT 25600, L. paracasei sp. paracasei A20 and L. plantarum A14. The studies revealed a decrease in surface tension of the culture broth for all the strains after 72 h incubation and the surface tension ranged from 1.4 to 6.4 mN m−1. The highest excreted biosurfactant rate was recorded for L. paracasei sp. paracasei A20 with surface tension of 6.4 mN m−1. However, the level of cell-bound biosurfactant was found to be higher than that of excreted molecules for all the strains. This is in contrast to other microorganisms

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such as Pseudomonas and Bacillus that primarily excrete biosurfactant into their medium. Biosurfactant production has also been reported for nonpathogenic L. delbrueckii by Thavasi et al. (2011a). This organism showed maximum glycolipid production of 5.35 mg L−1 at 144 h incubation with peanut oil cake as substrate, but higher production was recorded after the station-ary phase of growth. This was thought to be due to the release of cell-bound biosurfactant in the early stationary phase. In addition, L. delbrueckii could maximally degrade 61.25 % crude oil in the presence of fertilisers; hence the organism is both a biosurfactant producer and a hydrocarbon degrader. Lactobacilli are probiotics and non-pathogenic organisms designated “Generally Recognized as Safe” (GRAS) by the American Food and Drug Administration (FDA). The organism’s ability to utilise lactose instead of glucose via an alternative metabolic pathway for biosurfactant synthesis has proven them as ideal hosts for biotechnological techniques especially metabolic engineering towards large-scale pro-duction of cell-bound biosurfactants (Rodrigues et al. 2006a, b). Although the biosurfactant yield by these organisms is low, optimisation of culture conditions may improve their production.

Rhodococcus sp. are a group of aerobic, non- sporulating, Gram-positive bacteria that can be found in a wide range of environments. They are usually considered as experimentally advanta-geous due to their high growth rate and simple developmental cycle. These organisms are effective for the degradation of aromatic hydro-carbons, production of bioactive steroids, bio-desulphurisation of fossil fuel and biocon-version of waste products to valuable com-pounds (McLeod and Eltis 2008). Strains of these species have been reported as biosurfac-tant producers including R. erythropolis IMV Ac-5017 (Pirog et al. 2013) and Rhodococcus sp. MTCC 2574 (Mutalik et al. 2008). Furthermore, Pacheco et al. (2010) have identi-fied Rhodococcus erythropolis ATCC 4277 is a producer of a biosurfactant exhibiting excellent enhanced oil desorption from an oil shale. Rhodococcus ruber Z25 identified by 16 rDNA sequencing produced cell growth-associated

biosurfactants on n- hexadecane with maximum yield of 13.34 g L−1 at 44 h (Zheng et al. 2009). Rhodococcus spp. produce surface-active treha-lose lipids, and reports have shown that these surface-active compounds present interesting physico-chemical and biological properties. Trehalose lipids can significantly reduce the surface tension of water from 70 mN m−1 to 30.8 mN m−1 (Mutalik et al. 2008) and can form microemulsions (Zaragoza et al. 2013). In addi-tion, trehalose lipids have been reported to inhibit protein kinase activity in vivo (Isoda et al. 1997) and induce the cell lysis of E. coli IEM-1 as well as the vegetative and spore cells of Bacillus subtilis BT-2 (Pirog et al. 2013). They have also been found useful in soil biore-mediation and microbial enhanced oil recovery (Philip et al. 2002; Bell et al. 1998). This group of bacteria is considered as an ideal host for bio-technological production of non-toxic biosur-factant on industrial scales because of their genetic and catabolic diversity (associated pre-sumably with their large chromosome and three large linear plasmids (van der Geize and Dijkhuizen 2004; McLeod et al. 2006). These organisms are usually nonpathogenic with only two species R. fascians and R. equi (Goethals et al. 2001) identified as plant and animal patho-gens as well as causing infections in immune- compromised individuals. Nonpathogenic biosurfactant producers and their biosurfactants are shown in Table 1.2.

3.3 Lipopeptides and Phospholipids

Biosurfactants other than glycolipids produced by nonpathogenic organisms have been docu-mented in literature. Bacillus subtilis is a ubiqui-tous Gram-positive rod-shaped bacterium, found commonly in water, soil and air, and contributes to nutrient cycling in the environment. This organism is industrially useful as it is one of the most widely used bacteria in the production of enzymes (amylases, proteases, inosine, ribosides and amino acids) and speciality chemicals including biosurfactants (Erikson 1976). This bacterium

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has also been shown to produce a variety of antibacterial (Katz and Demain 1977) and antifungal (Korzybski et al. 1978) compounds including difficidin and oxydifficidin with wide spectrum of antibiotic activities against aerobic and anaerobic bacteria (Zimmerman et al. 1987). It has been used as a fungicide because it has the inherent ability to colonise root systems and to inhibit the growth of fungal plant pathogens (Kimura and Hirano 1988; Loeffler et al. 1986). Although B. subtilis has been associated with outbreaks of food poisoning (Gilbert et al. 1981; Kramer et al. 1982) and human infections espe-cially in hospitalised patients with surgical wounds, breast cancer and leukaemia (Logan 1988), the exact nature of its involvement in infections has not been established. However, a literature review by Edberg (1991) revealed that B. subtilis does not produce significant quantities of extra-cellular enzymes or virulence factors that would predispose it to cause infection. In addition, Ihde and Armstrong (1973) reported that B. subtilis is an organism with low virulence. The organism has therefore been classified as neither a human (Edberg 1991) nor plant (Claus and Berkeley 1986) pathogen. According to the National Institutes of Health (NIH) guidelines for research involving recombinant DNA molecules (US Department of Health and Human Services 1986) and the European Federation of Biotechnology guidelines, B. subtilis is considered a class 1 containment agent, and their industrial use in fermentation processes presents low risk of adverse effects to human health and environment. Bacillus subtilis produces an effective and active cyclic lipopeptide biosurfactant known as surfactin (Cooper et al. 1987; Peypoux et al. 1999). Das and Mukherjee (2007) reported the production of lipopeptide surfactants by two strains Bacillus subtilis DM-03 and Bacillus subtilis DM-04 on potato peels using both submerged and solid-state fermentation techniques. Production of biosur-factant with enhanced surface tension reduction of 26 mN m−1 and lower CMC of about 25 mg L−1 has been reported for B. subtilis PT2 strain (Pornsunthorntawee et al. 2008). Similarly, B. subtilis LB5a decreased surface tension to a minimum value of 26.6 mN m−1 with CMC of

33 mg L−1 (Nitschke and Pastore 2006). Cooper et al. (1981) had earlier reported production of lipopeptide biosurfactants by B. subtilis strains with a minimum surface tension of 25 mN m−1 and a CMC of 25 mg L−1. Surfactin has been demonstrated as one of most effective biosur-factants because of its high surface activity, effi-ciency in bioremediation and in situ microbial enhanced oil recovery (Mulligan 2005; Awashti et al. 1999; Besson and Michel 1992). Therefore, the production of biosurfactants from B. subtilis has the potential for large-scale bio-industrial development. Nonpathogenic lipopeptide- producing bacteria identified as Bacillus lentus and B. firmus have also been reported by Ibrahim et al. (2013) and Joshi et al. (2013).

Bacillus licheniformis is an important pro-ducer of lipopeptide biosurfactants (Biria et al. 2010) and has been used in industrial fermentation processes for over a decade for the production of several enzymes, antibiotics and special chemi-cals (Gherna et al. 1989; Eveleigh 1981). Although these Bacillus species have been reported to be associated with human infections, these occurred only in immunosuppressed indi-viduals following trauma and other predisposing factors. Therefore, according to the Biotechnology Program under the Toxic Substances Control Act under the US EPA (1997), B. licheniformis is classified as a nonpathogen and is not toxigenic. Furthermore, the National Institutes of Health and European Federation of Biotechnology guidelines have also placed this organism as a class 1 containment agent (Frommer et al. 1989). Nonpathogens other than Bacillus sp. such as Selenomonas ruminantium (Saimmai et al. 2013) and Brevibacterium aureum MSA13 (Kiran et al. 2010) have also been identified for the produc-tion of lipopeptide biosurfactants.

Corynebacterium sp. is Gram-negative, catalase- positive, rod-shaped facultative anaero-bic bacterium. Most members of this genus are nonpathogenic and industrially useful as they are known for the synthesis of amino acids, nucleo-tides and enzymes, for the bioconversion of steroids and for the degradation of hydrocarbons and are used in cheese ageing (Seidel et al. 2007; Natsch et al. 2005). The production of glycolipopeptide and

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phospholipid biosurfactants has been reported for two nonpathogenic species such as C. kutscheri and C. alkanolyticum ATCC 21511, respectively (Thavasi et al. 2007; Crosman et al. 2002).

3.4 Heteropolysaccharides

Halomonas are a group of Gram-negative, non- sporing bacteria usually found in many different extreme water and soil environments, mainly saline, hypersaline or alkaline ecosystems. They belong to the family of Halomonadaceae and are classified as Gammaproteobacteria currently made up of 10 genera. They are considered to be nonpathogenic (von Graevenitz et al. 2000) and are potential industrial microbes due to their abil-ity to synthesise microbial exopolysaccharides. Levan and mauran are examples of microbial polysaccharides from Halomonas spp. with a considerable market due to their exceptional per-formance at extreme industrial conditions (Poli et al. 2009; Llamas et al. 2006.) Although a few strains have been associated with certain human infections and contamination in a dialysis centre (Stevens et al. 2009), several Halomonas species have been classified as nonpathogens and also identified as biosurfactant producers. According to Donio et al. (2013), Halomonas sp. BS4 iso-lated from solar salt works has produced a het-eropolysaccharide biosurfactant that suppressed the proliferation of mammary epithelial carci-noma cells by 46.77 % at 25 μL concentration. In addition, the pure biosurfactant exhibited antibacterial activity on Staphylococcus aureus, Klebsiella pneumoniae, Streptococcus pyogenes and Salmonella typhi and antifungal activity on Aspergillus niger, Fusarium sp., Aspergillus flavus and Trichophyton rubrum. The biosurfac-tant was also found to display antiviral activity on white spot syndrome virus at high percentage (60, 80 and 100 %) and effectively suppressed the pathological effect of the virus. Gutierrez et al. (2013) have also shown the significance of exopolysaccharide (EPS) produced from marine Halomonas sp. TG89 in trace metal biogeochemical cycling. Calvo et al. (2002) have also documented the production of EPS from Halomona eurihalina.

This research revealed that EPS from Halomonas contained high levels of K, Ca, Mg and several trace metals such as Zn, Cu, Fe and metalloid Si and has the specific ability to bind Ca, Si, Fe, Mn, Mg and Al in marine sediments. Furthermore, the growth of marine diatom Thalassiosira weissflogii was enhanced in the presence of purified EPS or to marine sediments exposed to EPS, indicating that the trace metals bound to the EPS become biologically available for the diatoms to utilise for growth. This bacterium therefore has the poten-tial for the biotechnological development of safe antimicrobial and anticancer drugs as well as eco-friendly environmental products.

4 Production of Biosurfactant by Recombinant Strains

Pathogenicity may be avoided by the expression of biosurfactant production in heterologous microbial strains and mutants. Rhamnolipids can be synthesised by nonpathogenic heterologous strains provided with the rhamnosyltransferase genes rhlA, rhlB and rhlC. According to Cha et al. (2008), nonpathogenic heterologous P. putida 1067 (pNE2) expressing the rhlABRI gene from pathogenic P. aeruginosa EMS1 cultured in the mineral salt medium for 7 days in the pres-ence of 2 % soybean oil as the sole carbon source exhibited rhamnolipid productivity that was greater than that of P aeruginosa EMS1. Scope remains for optimisation of the production condi-tions potentially leading to increased biosurfac-tant production making this organism useful for industrial biosurfactant production. Furthermore, Ochsner et al. (1995) investigated the heterologous expression of rhlAB in P. fluorescens, P. putida and E. coli. The results showed 0.25 g L−1, 0.6 g L−1 and no rhamnolipid, respectively, for the organisms, but Wang et al. (2007) have reported rhamnolipid production in E. coli BL21 with the expression of rhlAB operon (Table 3).

In another study, rmlBDAC operon involved in dTDP-l-rhamnose biosynthesis was introduced into E. coli W3110 in addition to rhlAB operon, and a total final concentration of 120.6 mg L−1 mono-rhamnolipid was achieved using glucose as

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carbon substrate (Cabrera-Valladares et al. 2006). Similarly, recombinant E. coli HB101 was also detected to produce 52 mg L−1 rhamnolipid with oleic acid as substrate (Cabrera-Valladares et al. 2006). A successful development of a non-pathogenic host capable of producing mono- rhamnolipids using glucose as substrate has been reported by Wittgens et al. (2011). In this study, the synthesis of mono-rhamnolipid independent from biomass formation was done using P. putida KT2440 expressing the rhlAB genes from P. aeruginosa PA01. A sevenfold increase in the final rhamnolipid concentration from 0.22 to 1.5 g L−1 was recorded after genetic optimisation of the strain. The engineered strain exhibited some advantages compared to rhamnolipid pro-duction in P. aeruginosa. Firstly, these strains are nonpathogenic and can appropriately substitute the opportunistic pathogenic P. aeruginosa. Secondly, rhamnolipid production in the recombinant strains was void of the complex quorum sensing regulation. However, the production rate in the recombinant strain was about two thirds of that usually obtained in optimised fermentation with P. aeruginosa although there remains the possibility of increasing the production rate by increasing the availability of activated rhamnose in the medium. More importantly, compared to P. aeruginosa, it is the utilisation by the recombinant strains of glucose instead of hydrophobic substances. Glucose as a carbon substrate is relatively cheap and is applied in many biotechnological processes (Blank et al. 2008). Furthermore, these recombinant strains capable of substituting P. aeruginosa can

utilise hydrophilic substances, reaching a maximum rhamnolipid concentration in medium after 1–2 days. This is compared with the wild-type strain of P. aeruginosa PA01 that although it exhibits higher rhamnolipid production, it requires 1–3 days to reach their maximal levels. This reduction in process time exhibited by recombinant strains enhances the space-time yield for the process (Wittgens et al. 2011). According to this investigation, the engineered P. putida KT2440 is the second recombinant strain featuring the highest recorded space, time, and yield, therefore making this strain a potential industrial tool for biotechnological rhamnolipid synthesis.

Burkholderia kururiensis KP23(T), a trichloroethylene- degrading, nitrogen-fixing and plant growth-promoting bacterium, has been reported to produce rhamnolipids, and when genetically engineered with two biosynthetic enzymes from P. aeruginosa RhlA and RhlB, rhamnolipid production increased by sixfold compared to wild-type strain. Rhamnolipids pro-duced by the engineered strains were mainly mono-RL as opposed to wild-type strains B. kururiensis and P. aeruginosa that predominantly produce di-RLs. This organism is a promising biosurfactant producer with potential environ-mental and biotechnological application espe-cially due to its nonpathogenicity and compatibility with metabolic engineering proce-dures (Tavares et al. 2013).

5 Conclusion

The development of biosurfactant production in nonpathogenic organisms is a current challenge that is receiving increased attention in order to avoid pathogenicity and complex metabolic regu-lations. Most biosurfactant-producing organisms are pathogenic and difficult to handle in large- scale industrial processes. Pathogenicity of bio-surfactant producers is key factor to prevent large-scale production; therefore, the nonpathogenic eco-friendly organisms need to be explored further, and a library of collections is important for the future development in this area of study.

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Table 3 Recombinant biosurfactant producers

Biosurfactants Microbial strains References

Rhamnolipids Pseudomonas putida 1067(PNE2)

Cha et al. (2008)

Pseudomonas fluorescens

Ochsner et al. (1995)

E. coli W3110, E. coli HB101

Cabrera- Valladares et al. (2006)

P. putida KT2440 Wittgens et al. (2011)

Burkholderia kururiensis KP23(T)

Tavares et al. (2013)

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Acknowledgment The authors wish to thank the Commonwealth Commission for the financial support for this project.

References

Abalos A, Pinazo A, Infante MR, Casals M, Garcia F, Manresa A (2001) Physicochemical and antimicrobial properties of new rhamnolipids produced by Pseudomonas aeruginosa AT10 from soybean oil refin-ery wastes. Langmuir 17:1367–1371

Abouseoud M, Maachi R, Amrane A (2007) Biosurfactant production from olive oil by Pseudomonas fluores-cens. In: Méndez-Vilas A (ed) Communication current research and educational topics and trends in applied microbiology, pp 340–347

Amani H, Muller MM, Syldatk C, Hausmann R (2013) Production of microbial rhamnolipid by Pseudomonas aeruginosa MM1011 for ex-situ enhanced oil recov-ery. Appl Biochem Biotechnol 170:1080–1093

Andrä J, Rademann J, Howe J, Koch MHJ, Henie H, Zähringer U, Brandenburg K (2006) Endotoxin-like properties of a rhamnolipid exotoxin from Burkholderia (Pseudomonas) plantarii: immune cell stimulation and biophysical characterization. Biol Chem 387:301–310

Andrea H, West ET, Brittnacher MJ, Skerrett SJ, Miller SI (2008) Burkholderia thailandensis as a model system for the study of the virulence-associated type III secre-tion system of Burkholderia pseudomallei. Infect Immun 76:5402–5411

Anyanwu CU, Obi SKC, Okolo BN (2010) Lipopeptide biosurfactant production by Serratia marcescens NSK-1 strain isolated from petroleum-contaminated soil. J Appl Sci Res 7:79–87

Awashti N, Kumar A, Makkar R, Cameotra S (1999) Enhanced biodegradation of endosulfan a chlorinated pesticide in the presence of a biosurfactant. J Environ Sci Health B 34:793–803

Banat IM, Makkar RS, Cameotra SS (2000) Potential commercial applications of microbial surfactants. Appl Microbiol Biotechnol 53:495–508

Bell KS, Philp JC, Aw DWJ, Christofi N (1998) The genus Rhodococcus. J Appl Microbiol 85:195–210

Bergmann U, Scheffer J, Köller M, Schönfeld W, Erbs G, Müller FE, König W (1989) Induction of inflamma-tory mediators (histamine and leukotrienes) from rat peritoneal mast cells and human granulocytes by Pseudomonas aeruginosa strains from burn patients. Infect Immun 57:2187–2195

Bergström S, Theorell H, Davide H (1946) On a meta-bolic product of Pseudomonas pyocyania. Pyolipic acid active against M. tuberculosis. Ark Kemi Miner Geol 23A:1–12

Besson F, Michel G (1992) Biosynthesis of iturin and sur-factin by Bacillus subtilis: evidence for amino acid activating enzymes. Biotechnol Lett 14:1013–1018

Bharali P, Das S, Konwar BK, Thakur AJ (2011) Crude biosurfactant from thermophilic Alcaligenes faecalis: feasibility in petro-spill bioremediation. Int Biodeterior Biodegr 65:682–690

Biria D, Maghsoudi E, Roostaazad R, Dadafarin H, Lotfi AS, Amoozegar MA (2010) Purification and charac-terization of a novel biosurfactant produced by Bacillus licheniformis MS3. World J Microbiol Biotechnol 26:871–878

Bjarnsholt T, Jensen PO, Rasmussen TB, Christophersen L, Calum H, Hentzer ZM, Hougen HP, Rygaard J, Moser C, Eberl L, Hoiby N, Givskov M (2005) Garlic blocks quorum sensing and promotes rapid clearing of pulmonary Pseudomonas aeruginosa infections. Microbiology 151:3873–3880

Blank LM, Ionidis G, Ebert BE, Buhler B, Schmid A (2008) Metabolic response of Pseudomonas putida during redox biocatalysis in the presence of a second octanol phase. FEBS J 275:5173–5190

Bowen AB, Braden CR (2006) Invasive enterobacter sakazakii disease in infants. Emerg Infect Dis 12:1185–1189

Busscher HJ, van Hoogmoed CG, Geertsema-Doornbusch GI, van der Kuijl-Booij M, van der Mei HC (1997) Streptococcus thermophilus and its biosurfactants inhibit adhesion by Candida spp. on silicone rubber. Appl Environ Microbiol 63:3810–3817

Cabrera-Valladares N, Richardson A-P, Olvera C, Treviño LG, Déziel E, Lépine F, Soberón-Chávez G (2006) Monorhamnolipids and 3-(3-hydroxyalkanoyloxy) alkanoic acids (HAAs) production using Escherichia coli as a heterologous host. Appl Microbiol Biotechnol 73:187–194

Calvo C, Martinez-Checa F, Toledo FL, Porcel J, Quesada E (2002) Characteristics of bioemulsifiers synthesized in crude oil media by Halomonas eurihalina and their effectiveness in the isolation of bacteria able to grow in the presence of hydrocarbons. Appl Microbiol Biotechnol 60:347–351

Calvo C, Manzanera M, Siva-Castro GA, Uad I, González- López J (2009) Application of bioemulsifiers in soil oil bioremediation processes. Future prospects. Sci Total Environ 407:3634–3640

Centers for Disease Control and Prevention (CDC) (2002) Enterobacter sakazakii infections associated with the use of powdered infant formula – Tennessee, 2001. Morb Mortal Wkly Rep 51:297–300

Cha M, Lee N, Kim M, Kim M, Lee S (2008) Heterologous production of Pseudomonas aeruginosa EMS1 bio-surfactant in Pseudomonas putida. Bioresour Technol 99:2192–2199

Chi M-H, Hui RC-Y, Lu C-F, Yang L-C, Li S-Y (2013) Actinomycetoma caused by Nocardia otitidiscav-iarum: report of a case in Taiwan with long-term follow- up. Dermatol Sin 31:149–153

Christova N, Tuleva B, Lalchev Z, Jordanova A, Jordanov B (2004) Rhamnolipid biosurfactants produced by Renibacterium salmoninarum 27BN during growth on n-hexadecane. Z Naturforsch 59:70–74

[AU5]

[AU6]

C. Uzoigwe et al.

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1056

1057

1058

1059

1060

1061

1062

1063

1064

1065

1066

1067

1068

1069

1070

1071

Claus D, Berkeley RCW (1986) Genus bacillus Cohn 1872. In: Sneath PHA, Mair NS, Sharpe ME, Holt JG (eds) Bergey’s manual of systematic bacteriology, vol 2. Williams & Wilkins, Baltimore, pp 1105–1139

Cooper DG, Goldernberg BG (1987) Surface-active agents from two Bacillus species. Appl Environ Microbiol 53:224–229

Cooper DG, Macdonald CR, Duff SJB, Kosaric N (1981) Enhanced production of surfactin from Bacillus subti-lis by continuous product removal and metal cation additions. Appl Environ Microbiol 42:408–412

Cosson P, Zulianello L, Join-Lambert O, Faurisson F, Gebbie L, Benghezal M, van Delden C, Curty LK, Köhler T (2002) Pseudomonas aeruginosa virulence analyzed in a Dictyostelium discoideum host system. J Bacteriol 184:3027–3033

Costa SGVAO, Déziel E, Lépine F (2011) Characterization of rhamnolipid production by Burkholderia glumae. Lett Appl Microbiol 53:620–627

Crosman JT, Pinchuk RJ, Cooper DG (2002) Enhanced biosurfactant production by Corynebacterium alkano-lyticum ATCC 21511 using self-cycling fermentation. J Am Oil Chem Soc 79:467–472

Das K, Murkherjee AK (2007) Differential utilization of pyrene as the sole source of carbon by Bacillus subtilis and Pseudomonas aeruginosa strains: role of biosur-factants in enhancing bioavailability. J Appl Microbiol 102:195–203

De Baere T, Verhelst R, Labit C, Verschraegen G, Wauters G, Claeys G, Vaneechoutte M (2004) Bacteremic infection with Pantoea ananatis. J Clin Microbiol 42:4393–4395

Desai JD, Banat IM (1997) Microbial production of sur-factants and their commercial potential. Microbiol Mol Biol Rev 61:47–64

Donio MBS, Ronica FA, Viji VT, Velmurugan S, Jenifer JSCA, Michaelbabu M, Dhar P, Citarasu T (2013) Halomonas sp. BS4, a biosurfactant producing halophilic bacterium isolated from solar salt works in India and their biomedical importance. SpringerPlus 2:149–159

Dubeau D, Déziel E, Woods DE, Lépine F (2009) Burkholderia thailandensis harbors two identical rhl gene clusters responsible for the biosynthesis of rham-nolipids. BMC Microbiol 9:263

Dusane DH, Zinjarde SS, Venugopalan VP, McLean RJC, Weber MM, Rahman PKSM (2010) Quorum sensing: implications on rhamnolipid biosurfactant production. Biotechnol Genet Eng Rev 27:159–184

Dusane DH, Pawar VS, Nancharaiah YV, Venugopalan VP, Kumar AR, Zinjarade SS (2011) Anti-biofilm potential of a glycolipid surfactant produced by a trop-ical marine strain of Serratia marcescens. Biofouling 27:645–654

Edberg SC (1991) US EPA human health assessment: Bacillus subtilis. US Environmental Protection Agency, Washington, DC

Erikson RJ (1976) Industrial applications of the bacilli: a review and prospectus. In: Schlesinger D (ed) Microbiology. American Society for Microbiology, Washington, DC, pp 406–419

Eveleigh DE (1981) The microbial production of industrial chemicals. Sci Am 245:154–178

Ferraz C, De Araújo AA, Pastore GM (2002) The influ-ence of vegetable oils on biosurfactant production by Serratia marcescens. Appl Biochem Biotechnol 98–100:841–847

Frommer W, Ager B, Archer L, Brunius G, Collins CH, Donikian R, Frontali C, Hamp S, Houwink EH, Küenzi MT, Krämer P, Lagast H, Lund S, Mahler JL, Normand-Plessier F, Sargeant K, Tuijnenburg Muijs G, Vranch SP, Werner RG (1989) Safe biotechnology III. Safety precautions for handling microorganisms of different risk classes. Appl Environ Biotechnol 30:541–552

Fujita K, Akino T, Yoshioka H (1988) Characteristics of the heat-stable extracellular hemolysin from Pseudomonas aeruginosa. Infect Immun 56:1385–1387

Fullerton DG, Lwin AA, Lal S (2007) Pantoea agglomer-ans liver abscess presenting with a painful thigh. Eur J Gastroenterol Hepatol 19:433–435

Fung DC, Somerville M, Richardson PS, Sheehan JK (1995) Mucus glycoconjugate complexes released from feline trachea by a bacterial toxin. Am J Respir Cell Mol Biol 12:296–306

Gherna R, Pienta P, Cote R (1989) The American type culture collection catalogue of bacteria and phages. American Type Culture Collection, Rockville

Gilbert RJ, Turnbull PCB, Parry JM, Kramer JM (1981) Bacillus cereus and other Bacillus species: their part in food poisoning and other clinical infections. In: Berkeley RCW, Goodfellow M (eds) The aerobic endospore-forming bacteria; classification and identi-fication. Academic, London, pp 297–314

Glass MB, Gee JE, Steigerwalt AG, Cavuoti D, Barton T, Hardy RD, Godoy D, Spratt BG, Clark TA, Wilkins PP (2006) Pneumonia and septicemia caused by Burkholderia thailandensis in the United States. J Clin Microbiol 44:4601–4604

Goethals K, Vereecke D, Jaziri M, Van Montagu M, Holsters M (2001) Leafy gall formation by Rhodococcus fascians. Annu Rev Phytopathol 39:27–52

Govindammal M, Parthasarathi R (2013) Investigation on antimicrobial activity of biosurfactant produced by Pseudomonas fluorescens isolated from mangrove ecosystem. Int Res J Pharm 4:230–232

Graham A, Steel DM, Wilson R, Cole PJ, Alton EWFW, Geddes DM (1993) Effects of purified Pseudomonas rhamnolipids on bioelectric properties of sheep tra-cheal epithelium. Exp Lung Res 19:77–89

Gudiña EJ, Teixeira JA, Rodrigues LR (2011) Biosurfactant-producing Lactobacilli: Screening, pro-duction profiles, and effect of medium composition. Appl Environ Soil Sci 10:1155. http://dx.doi.org/10.1155/2011/201254

Gunther NW, Nuñez A, Fett W, Solaiman DKY (2005) Production of rhamnolipids by Pseudomonas chloro-raphis, a non-pathogenic bacterium. Appl Environ Microbiol 71:2288–2293

Production of Biosurfactants Using Eco-friendly Microorganisms

1072

1073

1074

1075

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1183

1184

1185

1186

1187

1188

1189

Gutierrez T, Berry D, Yang T, Mishamandani S, McKay L, Teske A, Aitken MD (2013) Role of bacterial exopoly-saccharides (EPS) in the fate of the oil released during the deepwater horizon oil spill. PLoS One 8(6):e67717. doi:10.1371/journal.pone. 0067717

Haraga A, West TE, Brittnacher MT, Skerrett SJ, Miller SI (2008) Burkholderia thailandensis as a model system for the study of the virulence-associated type III secre-tion system of Burkholderia pseudomallei. Infect Immun 76:5402–5411

Häussler S, Nimtz M, Domke T, Wray V, Steinmetz I (1998) Purification and characterization of a cytotoxic exolipid of Burkholderia pseudomallei. Infect Immun 66:1588–1593

Häussler S, Rohde M, von Neuhoff H, Nimtz M, Steinmetz I (2003) Structural and functional cellular changes induced by Burkholderia pseudomallei rhamnolipid. Infect Immun 71:2970–2975

Hayes D Jr, Murphy BS, Kuhn RJ, Anstead MI, Feola DJ (2009) Mucoid Inquilinus limosus in a young adult with cystic fibrosis. Pediatr Pulmonol 44:619–621

Heyd M, Franzreb M, Hausmann R, Syldatk C, Berensmeier S (2007) Integral continuous microbial rhamnolipid production. J Biotechnol 131:S77

Heyd M, Kohnert A, Tan TH, Nusser M, Kirschhöfer F, Brenner-Weiss G, Franzreb M, Berensmeier S (2008) Development and trends of biosurfactant analysis and purification using rhamnolipids as an example. Anal Bioanal Chem 391:1579–1590

Hörmann B, Müller MM, Syldatk C, Hausmann R (2010) Rhamnolipid production by Burkholderia plantarii DSM 9509T. Eur J Lipid Sci Technol 112:674–680

Hošaková M, Schreiberová O, Ježdik R, Chudoba J, Mosák J, Sigler K, Řezanka T (2013) Characterization of rhamnolipids produced by non-pathogenic Acinetobacter and Enterobacter bacteria. Bioresour Technol 130:510–516

Howe J, Bauer J, Andrä J, Schromm AB, Ernst M, Rössle M, Zähringer U, Rademann J, Brandenburg K (2006) Biophysical characterization of synthetic rhamnolip-ids. FEBS J 273:5101–5112

Hutkins R (2002) Streptococcus thermophiles LMD-9. JGI Microbes

Ibrahim ML, Ijah UJJ, Manga SB, Bilbis LS, Umar S (2013) Production and partial characterization of bio-surfactant produced by crude oil degrading bacteria. Int Biodeterior Biodegrad 81:28–34

Ihde DC, Armstrong D (1973) Clinical spectrum of infec-tion due to Bacillus species. Am J Med 55:839–845

Isoda H, Kitamoto D, Shinmoto H, Matsumura M, Nakahara T (1997) Microbial extracellular glycolipid induction of differentiation and inhibition of the pro-tein kinase C activity of human promyelocytic leuke-mia cell line HL60. Biosci Biotechnol Biochem 61:609–614

Jacobucci DFC, de Godoy Oriani MR, Durrant LR (2009) Reducing COD level on oily effluent by utilizing biosurfactant- producing bacteria. Braz Arch Biol Technol 52:1037–1042

Jain RM, Mody K, Mishra A, Jha B (2012) Isolation and structural characterization of biosurfactant produced by an alkaliphilic bacterium Cronobacter sakazakii isolated from oil contaminated wastewater. Carbohydr Polym 87:2320–2326

Jamal P, Nawawi W, Fazli WMFW, Md Zahangir A (2012) Optimum medium components for biosurfactant pro-duction by Klebsiella pneumoniae WMF02 utilizing sludge palm oil as a substrate. Aust J Basic Appl Sci 6:100–108

Janek T, Łukaszewicz M, Krasowska A (2013) Identification and characterization of biosurfactants produced by the arctic bacterium Pseudomonas putida BD2. Colloids Surf B: Biointerfaces 110:379–386

Jensen PØ, Bjarnsholt T, Phipps R, Rasmussen TB, Calum H, Christoffersen L, Moser C, Williams P, Pressler T, Givskov M, Hoiby N (2007) Rapid necrotic killing of polymorphonuclear leukocytes is caused by quorum-sensing-controlled production of rhamnolipid by Pseudomonas aeruginosa. Microbiology 153:1329–1338

Johnson MK, Boese-Marrazzo D (1980) Production and properties of heat-stable extracellular hemolysin from Pseudomonas aeruginosa. Infect Immun 29:1028–1033

Joost Wiersinga W, De Vos AF, De Beer R, Wieland CW, Roelofs JJTH, Woods DE, Van Der Poll T (2008) Inflammation patterns induced by different Burkholderia species in mice. Cell Microbiol 10:81–87

Jorfi S, Rezaee A, Mobeh-Ali G-A, Jaafarzadeh NA (2013) Application of biosurfactants produced by Pseudomonas aeruginosa SP4 for bioremediation of soils contaminated by pyrene. Soil Sediment Contam 22:890–911

Joshi SJ, Suthar H, Yadav AK, Hingurao K, Nerurkar A (2013) Occurrence of biosurfactant producing Bacillus spp. in diverse habitats. ISRN Biotechnol. http://dx.doi.org/10.5402/2013/652340

Kahveci A, Ascioglu E, Tigen E, Ari E, Arikan H, Odabasi Z, Ozener C (2011) Unusual causes of peritonitis in a peritoneal dialysis patient: Alcaligenes faecalis and Pantoea agglomerans. Ann Clin Microbiol Antimicrob 10:12

Kaliaperumal S, Srinivasan R, Gupta A, Parija SC (2006) Postoperative endophthalmitis due to an unusual pathogen: Alcaligenes faecalis. Eye 20:968–969

Katz E, Demain AL (1977) The peptide antibiotics of Bacillus: chemistry, biogenesis, and possible func-tions. Bacteriol Rev 41:449–474

Kharazmi A, Bibi Z, Nielsen H, Hoiby N, Döring G (1989) Effect of Pseudomonas aeruginosa rhamno-lipid on human neutrophil and monocyte function. APMIS 97:1068–1072

Kiliç AO, Pavlova SI, Ma WG, Tao L (1996) Analysis of Lactobacillus phages and bacteriocins in American dairy products and characterization of a phage isolated from yogurt. Appl Environ Microbiol 62:2111–2116

Kimura N, Hirano S (1988) Inhibitory strains of Bacillus subtilis for growth and aflatoxin-production of afla-toxigenic fungi. Agric Biol Chem 52:1173–1179

[AU7]

C. Uzoigwe et al.

1190

1191

1192

1193

1194

1195

1196

1197

1198

1199

1200

1201

1202

1203

1204

1205

1206

1207

1208

1209

1210

1211

1212

1213

1214

1215

1216

1217

1218

1219

1220

1221

1222

1223

1224

1225

1226

1227

1228

1229

1230

1231

1232

1233

1234

1235

1236

1237

1238

1239

1240

1241

1242

1243

1244

1245

1246

1247

1248

1249

1250

1251

1252

1253

1254

1255

1256

1257

1258

1259

1260

1261

1262

1263

1264

1265

1266

1267

1268

1269

1270

1271

1272

1273

1274

1275

1276

1277

1278

1279

1280

1281

1282

1283

1284

1285

1286

1287

1288

1289

1290

1291

1292

1293

1294

1295

1296

1297

1298

1299

1300

1301

1302

1303

1304

1305

1306

1307

Kiran GS, Sabu A, Selvin J (2010) Synthesis of silver nanoparticles by glycolipid biosurfactant produced from marine Brevibacterium casei MSA19. J Biotechnol 148:221–225

König B, Bergmann U, König W (1992) Induction of inflammatory mediators release (serotonin and 12-hydroxyeicosatetraenoic acid) from human plate-lets by Pseudomonas aeruginosa glycolipid. Infect Immun 60:3150–3155

Koo H-S, Kim J-S, Eom J-S, You J-Y, Park J-Y, Kim H-S, Song W, Cho HC, Lee KM (2006) Pseudooutbreak of Pantoea species bacteremia associated with contaminated cotton pledgets. Am J Infect Control 34:443–446

Körner RJ, Nicol A, Reeves DS, MacGowan AP, Hows J (1994) Ciprofloxacin resistant Serratia marcescens endocarditis as a complication of non-Hodgkin’s lym-phoma. J Infect 29:73–76

Korzybski T, Kowszyk-Gindifer Z, Kurylowicz W (1978) Antibiotics isolated from the genus Bacillus (Bacillaceae). In: Antibiotics – origin, nature and properties, vol 3. American Society of Microbiology, Washington, DC, pp 1529–1661

Kownatzki R, Tümmler B, Döring G (1987) Rhamnolipid of Pseudomonas aeruginosa on phosphatides and on phospholipase C activity. J Bacteriol 93:670–674

Kramer JM, Turnbull PCB, Munshi G, Gilbert RJ (1982) Identification and characterization of Bacillus cereus and other Bacillus species associated with foods and food poisoning. In: Corry JEL et al (eds) Isolation and identification methods for food poisoning organisms. Academic, London

Kratz A, Greenberg D, Barki Y, Cohen E, Lifshitz M (2003) Pantoea agglomerans as a cause of septic arthritis after palm tree thorn injury; case report and literature review. Arch Dis Child 88:542–544

Lai KK (2001) Enterobacter sakazakii infections among neonates, infants, children, and adults: case reports and a review of the literature. Medicine 80:113–122

Lee M, Kim MK, Vancanneyt M, Swings J, Kim S-H, Kang MS, Lee S-T (2005) Tetragenococcus koreensis sp. nov., a novel rhamnolipid-producing bacterium. Int J Syst Evol Microbiol 55:1409–1413

Lertpatanasuwan N, Sermsri K, Petkaseam A, Trakulsomboon S, Thamlikitkul V, Suputtamongkol Y (1999) Arabinose-positive Burkholderia pseudomallei infection in humans: case report. Clin Infect Dis 28:927–928

Limbago BM, Rasheed JK, Anderson KF, Zhu W, Kitchel B, Watz N, Munro S, Gans H, Banaei N, Kallen AJ (2012) IMP-producing carbapenem-resistant Klebsiella pneumoniae in the United States. J Clin Microbiol 49:4239–4245

Llamas I, del Moral A, Martnez-Checa F, Arco Y, Arias S, Quesada E (2006) Halomonas maura is a physiologi-cally versatile bacterium of both ecological and bio-technological interest. Antonie Van Leeuwenhoek 89:395–403

Loeffler W, Tschen JS-M, Vanittanakom N, Kugler M, Knorpp E, Hsieh T-F, Wu T-G (1986) Antifungal effects

of bacilysin and fengymycin from Bacillus subtilis F-29-3: a comparison with activities of other Bacillus antibiotics. J Phytopathol 115:204–213

Logan NA (1988) Bacillus species of medical and veteri-nary importance. J Med Microbiol 25:157–165

Maneerat S (2005) Production of biosurfactants using substrates from renewable-resources. Songklanakarin J Sci Technol 27:675–683

McClure CD, Schiller NL (1992) Effects of Pseudomonas aeruginosa rhamnolipids on monocyte-derived mac-rophages. J Leukoc Biol 51:97–102

McLeod MP, Eltis LD (2008) Genomic insights into the aerobic pathways for degradation of organic pollutants. Microbial biodegradation: genomics and molecular biology. Caister Academic Press. http://wwwhorizon-presscom/biod

McLeod MP, Warren RL, Hsiao WWL, Araki N, Myhre M, Fernandes C, Miyazawa D, Wong W, Lillquist AL, Wang D, Dosanjh M, Hara H, Petrescu A, Morin RD, Yang G, Stott JM, Schein JE, Shin H, Smailus D, Siddiqui AS, Marra MA, Jones SJ, Holt R, Brinkman FSL, Miyauchi K, Fukuda M, Davies JE, Mohn WW, Eltis LD (2006) The complete genome of Rhodococcus sp. RHA1 provides insights into a catabolic power-house. Proc Natl Acad Sci U S A 103:15582–15587

Mitchell RE, Teh KL (2005) Antibacterial iminopyrro-lidines from Burkholderia plantarii, a bacterial patho-gen of rice. Org Biomol Chem 3:3540–3543

Mukherjee S, Das P, Sen R (2006) Towards commercial production of microbial surfactants. Trends Biotechnol 24:509–515

Müller MM, Kügler JH, Henkel M, Gerlitzki M, Hörmann B, Pöhnlein M, Syldatk C, Hausmann R (2012) Rhamnolipids – next generation surfactants? J Biotechnol 162:366–380

Mulligan CN (2005) Environmental applications of bio-surfactants. Environ Pollut 133:183–198

Mutalik SR, Vaidya BK, Joshi RM, Desai KM, Nene SN (2008) Use of response surface optimization for the production of biosurfactant from Rhodococcus spp. MTCC 2574. Bioresour Technol 99:7875–7880

Natsch A, Gfeller H, Gygax P, Schmid J (2005) Isolation of a bacterial enzyme releasing axillary malodor and its use as a screening target for novel deodorant formu-lations. Int J Cosmet Sci 27:115–122

Nayak AS, Vijaykumar MH, Karegoudar TB (2009) Characterization of biosurfactant produced by Pseudoxanthomonas sp. PNK-04 and its application in bioremediation. Int Biodeterior Biodegrad 63:73–79

Nicas TI, Iglewki BH (1985) The contribution of exoprod-ucts to virulence of Pseudomonas aeruginosa. Can J Microbiol 31:387–392

Nitschke M, Pastore GM (2006) Production and properties of a surfactant obtained from Bacillus subtilis grown on cassava wastewaters. Bioresour Technol 97:336–341

Ochsner UA, Reiser J, Fiechter A, Witholt B (1995) Production of Pseudomonas aeruginosa rhamnolipid biosurfactants in heterologous hosts. Appl Environ Microbiol 61:3503–3506

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Oliveira FJS, Vazquez L, de Campos NP, de França FP (2009) Production of rhamnolipids by Pseudomonas alcaligenes strain. Process Biochem 44:383–389

Pacheco GJ, Ciapina EMP, de Barros GE, Junior NP (2010) Biosurfactant production by Rhodococcus erythropolis and its application to oil removal. Braz J Microbiol 41:685–693

Pal RB, Kale VV (1981) Acinetobacter calcoaceticus: an important opportunistic pathogen. J Postgrad Med 27:218–221

Pantazaki AA, Dimopoulou MI, Simou OM, Pritsa AA (2010) Sunflower seed oil and oleic acid utilization for the production of rhamnolipids by Thermus thermoph-ilus HB8. Appl Microbiol Biotechnol 88:939–951

Paulsen IT, Press CM, Ravel J, Kobayashi DY, Myers GSA, Mavrodi DV, DeBoy RT, Seshadri R, Ren Q, Madupu R, Dodson RJ, Durkin AS, Brinkac LM, Daugherty SC, Sullivan SA, Rosovitz MJ, Gwinn ML, Zhou L, Schneider DJ, Cartinhour SW, Nelson WC, Weidman J, Watkins K, Tran K, Khouri H, Pierson EA, Pierson LS III, Thomashow LS, Loper JE (2005) Complete genome sequence of the plant commensal Pseudomonas fluorescens Pf-5. Nat Biotechnol 23:873–878

Pelaez AI, Grrcia-Suarez MM, Manteca A, Melon O, Aranaz C, Cimadevilla R, Mendez FJ, Vazquez F (2009) A fatal case of Nocardia otitidiscaviarum pul-monary infection and brain abscess: taxonomic charac-terization by molecular techniques. Ann Clin Microbiol Antimicrob 8:11. doi:10.1186/1476-0711-8-11

Peypoux F, Bonmatin JM, Wallach J (1999) Recent trends in the biochemistry of surfactin. Appl Microbiol Biotechnol 51:553–563

Philp JC, Kuyukina MS, Ivshina IB, Dunbar SA, Christofi N, Lang S, Wray V (2002) Alkanotrophic Rhodococcus ruber as a biosurfactant producer. Appl Microbiol Biotechnol 59:318–324

Pirog TP, Antonyuk SI, Karpenko YV, Shevchuk TA (2009) The influence of conditions of Acinetobacter calcoaceticus K-4 strain cultivation on surface-active substances synthesis. Appl Biochem Microbiol 45:272–278

Pirog T, Sofilkanych A, Konon A, Shevchuk T, Ivanov S (2013) Intensification of surfactants’ synthesis by Rhodococcus erythropolis IMV Ac-5017, Acinetobacter calcoaceticus IMV B-7241 and Nocardia vaccinii K-8 on fried oil and glycerol con-taining medium. Food Bioprod Process 91:149–157

Poli A, Kazak H, Gürleyendağ B, Tommonaro G, Pieretti G, Öner ET, Nicolaus B (2009) High level synthesis of levan by a novel Halomonas species growing on defined media. Carbohydr Polym 78:651–657

Pornsunthorntawee O, Arttaweeporn N, Paisanjit S, Somboonthanate P, Abe M, Rujiravanit R, Chavadej S (2008) Isolation and comparison of biosurfactants pro-duced by Bacillus subtilis PT2 and Pseudomonas aeruginosa SP4 for microbial surfactant-enhanced oil recovery. Biochem Eng J 42:172–179

Rabiei A, Sharifinik M, Niazi A, Hashemi A, Ayatollahi S (2013) Core flooding tests to investigate the effects of

IFT reduction and wettability alteration on oil recovery during MEOR process in an Iranian oil reservoir. Appl Microbiol Biotechnol 97:5979–5991

Rahman PKSM, Gakpe E (2008) Production, characteri-sation and applications of biosurfactants – review. Biotechnology 7:360–370

Rahman KSM, Rahman TJ, McClean S, Marchant R, Banat IM (2002) Rhamnolipid biosurfactants production by strains of Pseudomonas aeruginosa using low- cost materials. Biotechnol Prog 18:1277–1281

Rahman KSM, Rahman TJ, Kourkoutas Y, Petsas I, Marchant R, Banat IM (2003) Enhanced bioremedia-tion of n-alkane in petroleum sludge using bacterial consortium amended with rhamnolipid and micronu-trients. Bioresour Technol 90:159–168

Rahman PKSM, Pasirayi G, Auger V, Ali Z (2010) Production of rhamnolipid biosurfactants by Pseudomonas aeruginosa DS10-129 in a microfluidic bioreactor. Biotechnol Appl Biochem 55:45–52

Rashid T, Ebringer A (2007) Ankylosing spondylitis is linked to Klebsiella- the evidence. Clin Rheumatol 26:858–864

Read RC, Roberts P, Munro N, Rutman A, Hastie A, Shryock T, Hall R, McDonald-Gibson W, Lund V, Taylor G (1992) Effect of Pseudomonas aeruginosa rhamnolipids on mucociliary transport and ciliary beating. J Appl Physiol 72:2271–2277

Reiling HE, Thanei-Wyss U, Guerra-Santos LH, Hirt R, Käppeli O, Fiechter A (1986) Pilot plant production of rhamnolipid biosurfactant by Pseudomonas aerugi-nosa. Appl Environ Microbiol 51:985–989

Řezanka T, Siristova L, Sigler K (2011) Rhamnolipid- producing thermophilic bacteria of species Thermus and Meiothermus. Extremophiles 15:697–709

Reznik GO, Vishwanath P, Pynn MA, Sitnik JM, Todd JJ, Wu J, Jiang Y, Keenan BG, Castle AB, Haskell RF, Smith TF, Somasundaran P, Jarrell KA (2010) Use of sustainable chemistry to produce an acyl amino acid surfactant. Appl Microbiol Biotechnol 86:1389–1397

Rodrigues L, Teixeira J, Oliveira R, van der Mei HC (2006a) Response surface optimization of the medium components for the production of biosurfactants by probiotic bacteria. Process Biochem 41:1–10

Rodrigues LR, Banat IM, Teixeira JA, Oliveira R (2006b) Biosurfactants: potential applications in medicine. J Antimicrob Chemother 57:609–618

Ron EZ, Rosenberg E (2002) Biosurfactants and oil reme-diation. Curr Opin Biotechnol 13:249–252

Rosenberg E, Ron EZ (1999) High- and low-molecular- mass microbial surfactants. Appl Microbiol Biotechnol 52:154–162

Rosenberg E, Schwartz Z, Tenebaum A, Rubinovitz C, Legmann R, Ron EZ (1989) A microbial polymer that changes the surface properties of limestone: effect of biodispersan in grinding limestone and making paper. J Dispers Sci Technol 10:241–250

Ryan KJ, Ray CG (2004) Sherris medical microbiology, 4th edn. McGraw-Hill, New York. ISBN 08385-8529-9

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C. Uzoigwe et al.

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1530

1531

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1534

1535

1536

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1540

1541

1542

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1544

1545

Saimmai A, Udomsilp S, Maneerat S (2013) Production and characterization of biosurfactant from marine bacterium Inquilinus limosus KB3 grown on low-cost raw materials. Ann Microbiol 63:1327–1339

Seidel M, Alderwick LJ, Sahm H, Besra GS, Eggeling L (2007) Topology and mutational analysis of the single Emb arabinofuranosyltransferase of Corynebacterium glutamicum as a model of Emb proteins of Mycobacterium tuberculosis. Glycobiology 17:210–219

Sierra G (1960) Hemolytic effect of a glycolipid produced by Pseudomonas aeruginosa. Antonie Van Leeuwenhoek 26:189–192

Silvi S, Barghini P, Aquilanti A, Juarez-Jimenez B, Fenice M (2013) Physiologic and metabolic characterization of a new marine isolate (BM 39) of Pantoea sp. pro-ducing high levels of exopolysaccharides. Microb Cell Fact 12:10

Simmons DG, Davis DE, Rose LP, Gray JG, Luginbuhl GH (1981) Alcaligenes faecalis- associated respira-tory disease of chickens. Avian Dis 25:610–613

Smith MD, Angus BJ, Wuthiekanun V, White NJ (1997) Arabinose assimilation defines a non-virulent bio-type of Burkholderia pseudomallei. Infect Immun 65:4319–4321

Soberón-Chávez G, Lépine F, Déziel E (2005) Production of rhamnolipids by Pseudomonas aeruginosa. Appl Microbiol Biotechnol 68:718–725

St Denis M, Ramotar K, Vandemheen K, Tullis E, Ferris W, Chan F, Lee C, Slinger R, Aaron SD (2007) Infection with Burkholderia cepacia complex bacteria and pulmonary exacerbation of cystic fibrosis. Chest 131:1188–1196

Stevens DA, Hamilton JR, Johnson N, Kim KK, Lee J-S (2009) Halomonas, a newly recognized human patho-gen causing infections and contamination in a dialysis center: three new species. Medicine 88:244–249

Stoimenova E, Vasileva-Tonkova E, Sotirova A, Galabova D, Lalchev Z (2009) Evaluation of different carbon sources for growth and biosurfactant production by Pseudomonas fluorescens isolated from wastewaters. Z Naturforsh C 64:96–102

Stover CK, Pham XQ, Erwim AL, Mizoguchi SD, Warrener P, Hickey MJ, Brinkman FSL, Hufnagle WO, Kowalik DJ, Lagrou M, Garber RL, Goltry L, Tolentino E, Westbrock-Wadman S, Yuan Y, Brody LL, Coulter SN, Folger KR, Kas A, Larbig K, Lim R, Smith K, Spencer D, Wong GK-S, Wu Z, Paulsen IT, Reizer J, Saier MH, Hancock REW, Lory S, Olson MV (2000) Complete genome sequence of Pseudomonas aeruginosa PAO1, an opportunistic pathogen. Nature 406:959–964

Stutts MJ, Schwab JH, Chen MG, Knowles MR, Boucher RC (1986) Effects of Pseudomonas aeruginosa on bronchial epithelial ion transport. Am Rev Respir Dis 134:17–21

Tahmourespour A, Salehi R, Kermanshahi RK (2011) Lactobacillus acidophilus-derived biosurfactant effect on gtfB and gtfC expression level in Streptococcus mutans biofilm cells. Braz J Microbiol 42:330–339

Tavares LFD, Silva PM, Junqueira M, Mariano DCO, Nogueira FCS, Domont GB, Freire DMG, Neves BC (2013) Characterization of rhamnolipids produced by wild-type and engineered Burkholderia kururiensis. Appl Microbiol Biotechnol 97:1909–1921

Taylor JR, Mitchell D (2007) The wonder of probiotics. St Martin’s Press, New York

Thavasi R, Jayalakshmi S, Balasubramanian T, Banat IM (2007) Biosurfactant production by Corynebacterium kutscheri from waste motor lubricant oil and peanut oil cake. Lett Appl Microbiol 45:686–691

Thavasi R, Jayalakshmi S, Banat IM (2011a) Application of biosurfactant produced from peanut oil cake by Lactobacillus delbrueckii in biodegradation of crude oil. Bioresour Technol 102:3366–3372

Thavasi R, Subramanyam Nambaru VRM, Jayalakshmi S, Balasubramanian T, Banat IM (2011b) Biosurfactant production by Pseudomonas aeruginosa from renew-able resources. Indian J Microbiol 51:30–36

Toribio J, Escalante AE, Soberón-Chávez G (2010) Rhamnolipids: production in bacteria other than Pseudomonas aeruginosa. Eur J Lipid Sci Technol 112:1082–1087

Tuleva BK, Ivanov GR, Christova NE (2002) Biosurfactant production by a new Pseudomonas putida strain. Z Naturforsch C 57:356–360

Tümmler B, Koopmann U, Grothues D, Weissbrodt H, Steinkamp G, von der Hardt H (1991) Nosocomial acquisition of Pseudomonas aeruginosa by cystic fibrosis patients. J Clin Microbiol 29:1265–1267

Urakami T, Ito-Yoshida C, Araki H, Kijima T, Suzuki K-I, Komagata K (1994) Transfer of Pseudomonas planta-rii and Pseudomonas glumae to Burkholderia as Burkholderia spp. and description of Burkholderia vandii sp. nov. Int J Syst Evol Bacteriol 44:235–245

US Department of Health and Human Services (1986) NIH guidelines for research involving recombinant DNA molecules; Notice 51 FR 16958

US Environmental Protection agency (1997) Bacillus licheniformis final risk assessment. http://epagov/bio-tech_rule/pubs/fra/fra005htm

Van Bogaert INA, Saerens K, De Muynck C, Develter D, Soetaert W, Vandamme EJ (2007) Microbial produc-tion and application of sophorolipids. Appl Microbiol Biotechnol 76:23–34

van der Geize R, Dijkhuizen L (2004) Harnessing the catabolic diversity of Rhodococci for environmental and biotechnological applications. Curr Opin Microbiol 7:255–261

Vasileva-Tonkova E, Gesheva V (2007) Biosurfactant pro-duction by Antarctic facultative anaerobe Pantoea sp. during growth on hydrocarbons. Curr Microbiol 54:136–141

Vasileva-Tonkova E, Galabova D, Stoimenova E, Lalchev Z (2006) Production and properties of biosurfactants from a newly isolated Pseudomonas fluorescens HW-6 growing on hexadecane. Z Naturforsch 61:553–559

Production of Biosurfactants Using Eco-friendly Microorganisms

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1659

1660

1661

1662

1663

von Graevenitz A, Bowman J, del Notaro C, Ritzler M (2000) Human infection with Halomonas venusta following fish bite. J Clin Microbiol 38:3123–3124

Vyas TK, Dave BP (2011) Production of biosurfactant by Nocardia otitidiscaviarum and its role in biodegrada-tion of crude oil. Int J Environ Sci Technol 8:425–432

Walter V (2009) New approaches for the economic production of rhamnolipid biosurfactants from renew-able resources. Dissertation, Karlsruhe Institute of Technology, Germany

Wang Q, Fang X, Bai B, Liang X, Shuler PJ, Goddard WA III, Tang Y (2007) Engineering bacteria for production of rhamnolipid as an agent for enhanced oil recovery. Biotechnol Bioeng 98:842–853

Wei Y-H, Lai H-C, Chen S-Y, Yeh M-S, Chang J-S (2004) Biosurfactant production by Serratia marcescens SS-1 and its isogenic strain SMΔR defective in SpnR, a quorum-sensing LuxR family protein. Biotechnol Lett 26:799–802

Wellinghausen N, Andreas E, Sommerburg O (2005) Inquilinus limosus in patients with cystic fibrosis in Germany. Emerg Infect Dis 11:457–459

Wiens GD, Rockey DD, Wu Z, Chang J, Levy R, Crane S, Chen DS, Capri GR, Burnett JR, Sudheesh PS, Schipma MJ, Burd H, Bhattacharyya A, Rhodes LD, Kaul R, Strom MS (2008) Genome sequence of the fish pathogen Renibacterium salmoninarum suggests reductive evolution away from an environmental Arthrobacter ancestor. J Bacteriol 190:6970–6982

Wittgens A, Tiso T, Arndt TT, Wenk P, Hemmerich J, Müller C, Wichmann R, Küpper B, Zwick M, Wilhelm S, Hausmann R, Syldatk C, Rosenau F, Blank LM (2011) Growth independent rhamnolipid production

from glucose using the non-pathogenic Pseudomonas putida KT2440. Microb Cell Fact 10:80

Wuthiekanun V, Smith MD, Dance DAB, Walsh AL, Pitt TL, White NJ (1996) Biochemical characteristics of clinical and environmental isolates of Burkholderia pseudomallei. J Med Microbiol 45:408–412

Yalçin E, Ergene A (2010) Preliminary characterization of biosurfactant produced by microorganisms isolated from refinery wastewaters. Environ Technol 31:225–232

Zaragoza A, Teruel JA, Aranda FJ, Ortiz A (2013) Interaction of trehalose lipid biosurfactant produced by Rhodococcus erythropolis 51T7 with a secretory phospholipase A2. J Coll Interf Sci 408:132–137

Zheng C, Li S, Yu L, Huang L, Wu Q (2009) Study of the biosurfactant-producing profile in a newly isolated Rhodococcus ruber strain. Ann Microbiol 59:771–776

Zhong H, Zeng GM, Yuan XZ, Fu HY, Huang GH, Ren FY (2007) Adsorption of dirhamnolipid on four micro-organisms and the effect on cell surface hydrophobic-ity. Appl Microbiol Biotechnol 77:447–455

Zimmerman SB, Schwartz CD, Monaghan RL, Pleak BA, Weissberger B, Gilfillan EC, Mochales S, Hernandez S, Currie SA, Tejera E, Stapley EO (1987) Difficidin and oxydifficidin: novel broad spectrum antibacterial antibiotics produced by Bacillus subtilis. J Antibiot 40:1677–1681

Zulianello L, Canard C, Köhler T, Caille D, Lacroix J-S, Meda P (2006) Rhamnolipids are virulence factors that promote early infiltration of primary human air-way epithelia by Pseudomonas aeruginosa. Infect Immun 74:3134–3147

C. Uzoigwe et al.

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