Biodeterioration - CICY.mx · Water content: amount of water content inside de rock. Water...
Transcript of Biodeterioration - CICY.mx · Water content: amount of water content inside de rock. Water...
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Mérida, Yucatán Octubre 12 [email protected]
Departamento de Física Aplicada Cinvestav- Mérida
Nanomateriales para la conservación de
bienes patrimoniales con actividad
antimicrobiana
Nanomaterials with antimicrobial activity
to preserve cultural heritage assets
Dra. Patricia Quintana
Tzompantlí, Chichén itza Lichens
Tzompantli Templo de las calaveras Chichen Itzá
Juego de Pelota de Chichen Itza
Algae: Trentepohlia sp
cyanobacteria
The breakdown of materials by
microbial action (Hueck, 1965)
The biodeterioration processes are
favored during the growth of
microorganisms, therefore the
decomposition and disintegration of
stones is due to the formation of
biominerals.
Rock: porous material
Environmental factors : weather, light,
humidity, solar radiation cycles, etc.
Biodeterioration
pitting
mosses
Biodeterioration by Microorganisms
Interpenetration of hyphae
Fungal growth
Meteorization cycles due to microorganisms Chemical, physical and biological interactions between the stone-atmosphere-microorganisms. (GADD Mycologist, 2004)
Fungal hyphae penetrates the surface of the stone to obtain nutrients and excreted small amounts of acid, which cause superficial damage to limestone
HYPHAE
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Biomineralization: The formation of hard mineral
deposits through a living organism
H2CO3 Ca+ + (HCO3)-
H2C2O4 Ca+ + (C2O4)2-
CaC2O4·2H2O Weddellite
Hydrated Calcium Oxalates
Tetragonal: a=b=12.33Å, c=7.35Å =β= γ= 90°
Monoclinic: a= 6.29Å, b=14.58Å, c=10.11Å =γ= 90°, β=109.47°
CaC2O4·H2O Whewellite
H2O + CO2 H2CO3 o H2C2O4 organic acids (carbonic)
CaCO3 +
Biomineralization: The synthesis of inorganic crystalline or amorphous minerals by living organisms often forms hard mineralized tissues.
These organisms produce inorganic solids with specific chemical and morphologic characteristics with organized crystals.
Minerals Biominerals
Calcium
carbonates
Calcite
Aragonite
Vaterite
Calcium oxalates Whewellite
Weddellite
Amorphous Silica SiO2 nH2O
Iron oxide Ferrihydrite
Sulfates Gypsum
Calcium
phosphates HAP
Microorganisms
a) Fungi b) Bacteria
c) Cyanobacteria and
microalgaes
d) Líchens
Mainly microorganisms which are involved in deterioration
processes of calcareous material
Prevention and remediation methods
When biological growths are found to be damaging
historical or modern constructions, requires removal
or management. The following actions may be
considered
Type of microorganisms
Weather conditions
Type of stone (composition, porosity,
density, surface, etc.)
Methods Advantages Disadvantages
Physical
Mechanical, washing
(water or vapor pressure)
and brushing the
biological material
Traditional method (usually
applied) good to remove algae,
lichens and mosses
The area is clean for a short period
of time, it only removes the
superficial mycelium, however
water goes into internal porous
favors the microorganisms to grow
again.
UV Energy penetration is very
effective on the surface
The work area is small and can
react with other mineral compounds
Chemical
Biocides Diluted in water or organic
solvents. Health dangerous
Fumigation Is fast removing fungi
microorganisms, insects, etc.
Gases are toxic, only applies in
close spaces
Anoxic atmosphere Fungi are susceptible with the
absence of oxygen
Large exposition period,
Expensive equipment
P. Fernández (2006)
OBJECTIVE
Preserve and protect the cultural heritage and modern
buildings, developing new coatings and biocides in order to
avoid the deterioration of petrous material
Develop new coatings compatible with the construction materials to preserve and
extend the useful life.
Evaluate In vitro the growth of microorganisms (antimicrobial and bactericide
activity) in calcareous rocks with the coatings
Stablish the mechanism of biocide or biostatic action of the coatings (CMF, CMB,
CMI; minimum concentration fungicidal, bactericidal, inhibitory) and the action
mode to prevent the organism to growth, and analysis the structural damage, etc.
Evaluate the effectivity against deterioration in situ of the calcareous rocks with
the coatings, when are exposed to different environments.
In Mexico, polymer coatings were applied to frescoes at 1990s; after 10 years it cause mechanical stresses and crystallization of salts leading to accelerated disintegration. also, the polymers became discolored and brittle. In 2008, Baglioni started to work with the Mexican INAH to come up with a removal treatment for murals at the Mayan site Mayapan
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• Synthesis of protective antifungal coatings of Ca(OH)2 + ZnO
(TiO2)
• Characterization of the natural limestone rocks collected from
quarries of Yucatan state
• Microbial and bacterial colonization analysis on the surface of
the rocks
• S. De la Rosa García, O.Ortega-Morales, Ch. Gaylarde, M. Beltrán-García, P. Quintana, M. Reyes-Estebanez,Influence of fungi in the weathering of limestone of Mayan monuments, Rev. Mx Micología 33 (2011) 43-51 (Uxmal)
• O. Ortega-Morales, S. Nakamura, G. Montejano-Zurita, J. C. Camacho-Chab, P. Quintana, S.de la Rosa García. Implications of colonizing biofilms and microclimate on west stucco masks at north Acropolis, Tikal, Guatemala. Heritage Sc. J 1:32 (2013) 2-8
Commercial Ca(OH)2 nanoparticles for the consolidation of immovable works of art, P. Baglioni, et al, Appl. Phys A (2014), 114 (3), 723
Chamber tomb on Ixcaquixtla (Puebla, Mexico). Painted layer before the application of Ca(OH)2 nanoparticles. The consolidation treatment allowed the removal of salts, recovering and revealing larger portions of the painted layer.
Optical microscope images and SEM of the red pigment painted layer in Calakmul (Mexico) Maya archaeological site. Bar is 100 μm
Before treatment After treatment
Before treatment After treatment Before treatment After treatment
Nanorestore® formulation Ca(OH)2 NPs in 2-propanol, 5 g/L Nps size 250 nm
Agitation cte
24°C 15 h
Precipitate
Washing/centrifugate (Acetone-H2O 6:3 mL)
Dry
Coating synthesis by SOL-GEL
1 11
2
3
45 6
7
8
9
1 10
2
3
45 6
7
8
9
1 10
70 °C
Titanium butoxide
H2O, tert-butanol, pH
60-90°C
Ti- butoxide Zn(ac)2 (NaOH) CaCl2.2H2O
Mix alcohol + H2O (5h)
Reflux system
Ca(OH)2-xZnO (x=10,20,30,40 y 50%) Ca(OH)2-xTiO2 (x=10,20 y 30%)
Start in 2010
SEM image of nanoparticles of: (a) Ca(OH)2, (b) ZnO and (c) TiO2
2m
(a)
100nm
(b)
100nm
(c)
15-30 nm spherical particles
10-20 nm nanoparticles
500 nm Hexagonal flakes
Culture and fungi growth Dra. Susana de la Rosa-García
Depto. Microbiología Ambiental y Biotecnología, UAC - Inoculation
- Evaluate microorganisms growth
In vitro, In situ,
- Light/darkness, UV
Stablish the action mode
Fungicidal/fungistatic
Bactericidal/bacteriostatic
Fungi and bacteria
- glass
- Limestone rocks
Specific medium Fungi:
Papa Dextrosa Agar (PDA)
Specific medium:
Bacteria Tripticaseína
Soya Agar (TSA)
Yeast (PDA)
Adjusted concentrations for
culture of microorganisms
Lab. de microbiología ambiental y biotecnología
UAC
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Aspergillus niger
Penicillium oxalicum
Fungi
Fungi colonization on the coatings on glass slides
and on the surface of the rocks
Control Aspergillus niger
Control Penicillium oxalicum
Coating
composition
A. niger P. oxalicum
Time (h) 24 72 120 24 72 120
Control
(untreated)
(–) (–) (–) (–) (–) (–)
Ca (OH)2 (++) (++) (++) (++) (++) (++)
Ca (OH)2 TiO2 10% (++) (+) (–) (++) (++) (++)
Ca (OH)2 TiO2 20% (++) (+) (+) (++) (++) (++)
Ca (OH)2 TiO2 30% (++) (+) (+) (++) (++) (++)
ZnO (+++) (+++) (+++) (+++) (+++) (+++)
Ca (OH)2 ZnO 10% (++) (++) (++) (+++ ) (+++) (+++)
Ca (OH)2 ZnO 30% (+++) (+++) (++) (+++) (+++) (+++)
Ca (OH)2 ZnO 50% (+++) (+++) (+++) (+++) (+++) (+++)
(+++) effective (++) moderate, (+) poor (–) ineffective
Antifungal activity of antifungal coatings (in vitro) on glass slides under natural illumination conditions
DRX a) before and b) after inoculation
1) Without coating; 2) Ca(OH)2-50%TiO2 3) Ca(OH)2-50%ZnO
A. niger P. oxalicum
Semi-quantitative XRD of different nanosystem coatings on glass slides after 120 days. Before and after inoculation with two fungi and two types of treatments: in darkness (D) and under simulated photoperiod conditions (D/L).
Ca(OH)2 Ca(OH)2-xZnO
Ca(OH)2-xZnO P. oxalicum
Ca(OH)2-xZnO A. niger
DRX analysis on coatings Glass slide
A.Niger (NL)
A.Niger (D)
P. oxalicum (NL)
P. oxalicum (D)
Coating without fungi
photoperiod (NL) darkness (D)
Characterization of the natural
limestone rocks
collected from quarries of Yucatan state
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Dry density: material mass (volume) including empty spaces.
Effective porosity: connected porous volume in a volume unity of rock.
Water content: amount of water content inside de rock.
Water absorption: percentage of water that a rock can retain before the measurement.
Physical properties of limestones
PROPERTY FORMULA NORM
Density ISRM 1979
Porosity ISRM 1981
TSE 1987
Water
content
UNE-EN
1936:1999
RILEM 1980.
Water
absorption
UNE-EN
13755:2001;
NORMA 7/81
V
Md S
%100XV
VV
%100XM
MM
S
sub
%100XM
MMWA
S
Ssat
Ms = Dry mass; V = total volume;
Vv = Empty space volume
Msub= mass submerged; Msat= saturated mass
Rock Density
(g/cm3)
% Water
Content
% Effective
Porosity
% Water
Absorption
A 2.178 0.12 6.16 6.59
B 2.547 0.03 1.27 1.22
C 2.477 0.27 1.71 1.01
White flagstone from Ticul: carbonated rock with a micritic matrix (59%) and cemented sparitic calcite (18%) with a few bivalve mollusks and echinoderms Biomicrita (Folk, 1962) o Grainstone (Wright, 1992)
Porosity of ~ 5%
Ticimul: carbonated rocks mainly with bioclasts (80%) with a micritic matrix (9%), and patches of microsparite and sparite (6%). Biomicrita (Folk, 1962) o Rudstone (Wright, 1992)
Porosity of ~ 10%
A C B
Pisté: Micritic calcite matrix (16%) with partially sparitic cement (67%), few bioclasts and fragments of bivalves (11%) , with interlayer of iron oxides patches (4%)
Intramicrita (Folk, 1962) o Rudstone (Wright, 1992)
Porosity of ~18%
Petrographic Analysis
5 10 15 20 25 30 35 40 45 50 55 60
M
HFe
2
C
T+C
A
Q
T+C
con HCl
sin HCl
T = Tosudita
C = Caolinita
Q = Cuarzo
M = Microclina
H = Hematita
A = Anastasa
Fe = Hidroxido
oxido de Fe
MUESTRA (A)
In
ten
sid
ad
Re
lati
va
(a
.u.)
5 10 15 20 25 30 35 40 45 50 55 60
H
MMo
2
Mo
A
T+C
MUESTRA (B)T = Tosudita
C = Caolinita
Mo = Montmorillonita
Q = Cuarzo
M = Microclina
A = Anatasa
H = Hematita
C
Q T+C
con HCl
sin HCl
In
ten
sid
ad
Re
lati
va
(a
.u.)
Str
uctu
ral cha
racte
rizatio
n
4000 3500 3000 2500 2000 1500 1000 500
0
20
40
60
80
100
% T
rans
mita
ncia
(u. a
.)
longitud de onda (cm-1)
a)
OH
Si-O-Si
H-O-H
4000 3500 3000 2500 2000 1500 1000 500
0
20
40
60
80
100
Longitud de onda (cm-1)
% T
rans
mita
ncia
(u.
a.)
a)
OH
C-O-O
(O=)PO-H
CH3
CO3=
MgAlOH
CO=
SI-O-SI
Antifungal activity (in situ) on limestone rocks
after removing the biofilm
P. oxalicum A. niger Natural stone
White flagstone Ticul
Piste
Limestone
coupons A B
Coating
composition A. niger P. oxalicum A. niger P. oxalicum
Control
(untreated) (–)1 (–)1 (–)1 (–)1
Ca(OH)2-50%TiO2 (+)14 (+++)6 (++)6 (+++)6
TiO2 (++)14 (++)12 (++)6 (+++)6
Ca(OH)2-50%ZnO (+++)6 (+++)6 (+++)6 (+++)6
ZnO (+++)6 (+++)6 (+++)6 (+++)6
Antifungal activity of coatings applied to two different limestone coupons after 21 days of exposure under simulated photoperiod
(+++) effective (++) moderate, (+) poor (–) ineffective.
The superscript shows for how many days after inoculation the antifungal activity decreased with time
Laboratory hood near to a window
XRD analysis comparison between different coatings before and after the inoculation (21 days) with two fungi under photoperiod conditions.
a & b Coupon A Pisté
c & d Coupon B White flagstone (1) Control
(2) Ca(OH)2-50%TiO2 (3) Ca(OH)2-50%ZnO
A. niger P. oxalicum
Gomez-Ortiz, N., De la Rosa-Garcia, S.C., Gonzalez-Gomez, W.S., Soria-Castro, M., Quintana, P., Oskam, G., Ortega-
Morales, B.O. Antifungal coatings based on Ca(OH)2 mixed with ZnO/TiO2 nanomaterials for protection of limestone
monuments. ACS Applied Materials & Interfaces 5 (2013) 1556-1565
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Transversal cut side view of the surface of inoculated limestones
(e) Coupon A Ca(OH)2-50%TiO2 P. oxalicum
(b) Coupon B weddellite (a) Coupon A TiO2 A.niger (c) B whewellite P Oxalicum
(d) B TiO2 A. niger inhomogeneous layer, showed larger pores and cracks, fragile coating
(f) Coupon A Ca(OH)2-50%ZnO A. niger. Homogeneous layer and better adhered to the rock
B Ca(OH)2–50%ZnO
Limestone (2.3mm) cross-sectional images showing hyphae penetration with and without coating
Coupon A A niger
Coupon B A niger
B TiO2
No coating
Coating thickness
0.00
20.00
40.00
60.00
80.00
100.00
10% 20% 30% 40% 50%
Síntesis de Ca(OH)2-xZnO S/C
Calcita
Portlandita
Zincita
Hidróxido doble de Ca y Zinc
0.00
20.00
40.00
60.00
80.00
100.00
10% 20% 30% 40% 50%
Síntesis Ca(OH)2-xZnO Penicillium sp. D/N
Calcita
Vaterita
Zincita
Whewelita
Weddelita
0.00
20.00
40.00
60.00
80.00
100.00
10% 20% 30% 40% 50%
Síntesis Ca(OH)2-xZnO Aspergillus sp. D/N
Calcita
Vaterita
Zincita
Semi-quantitative XRD of different nanosystem coatings on glass slides
Sample A Sample B
Elements
Zone 1
10m
Zone 2
41.3m
Zone 3
48m Zone 4
Zone 1
4m
Zone 2
9m
Zone 3
16m Zone 4
C 17.35 16.32 14.82 14.03 19.28 17.80 15.62 18.44
O 50.94 47.14 45.76 43.20 52.24 50.30 45.61 48.36
Ca 30.49 31.71 29.91 40.41 23.98 26.46 30.86 33.20
Zn 1.22 4.83 9.51 ─ 4.50 5.44 7.91 ─
Al ─ ─ ─ 1.06
Si ─ ─ ─ 1.30
Total 100 100 100 100 100 100 100 100
Rock type A Piste Rock type B
48μm
18μm
ZnO
cross-sectional images showing coating thickness
White flagstone Ticul
Rock
Sample A Sample B
Elements
Zone 1
7m
Zone 2
21.8m
Zone 3
32m
Zone 1
4m
Zone 2
13m Zone 3
C 19.44 18.72 14.02 18.61 16.92 18.44
O 54.42 43.99 43.25 50.60 42.80 48.36
Ca 23.98 26.64 40.41 28.62 33.70 33.20
Zn 1.58 9.50 ─ 2.17 6.58 ─
Al 0.26 0.56 1.03 ─ ─ ─
Si 0.32 0.59 1.30 ─ ─ ─
Total 100 100 100 100 100 100
Sample A Sample B
17 μm 21.8 μm
Ca(OH)2-18%ZnO
Muestra A Muestra B
Elementos
Zona 1
6m Zona 2
Zona 1
5m
Zona 2
15m Zona 3
C 12.94 14.02 16.30 14.23 18.44
O 36.66 43.20 45.97 39.25 48.36
Ca 29.50 40.41 22.60 23.59 33.20
Zn 20.90 ─ 15.13 22.93 ─
Al ─ 1.03
Si ─ 1.30
Total 100 100 100 100 100
Muestra A Muestra B
12.6μm 18.5μm
Ca(OH)2-50%ZnO
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A. niger P. oxalicum ZnO
Rock A
Rock B
Coating thickness interlayer between fungy and stone
22.5m
21.2m
1.69m 1.16m
fungi
25.3 μm
Rock A
Rock B
12.2μm 8.5μm
Thickness layer of Ca(OH)2-18%ZnO coating
42.4 μm
fungi
13μm
12μm
Thickness layer of Ca(OH)2-50%ZnO coating
8.68μm 7.1μm
Rock A
Rock B fungi
Cross-section showing hyphae penetration A. niger
Roca A Roca B
A con Ca(OH)2 - 50%ZnO B con Ca(OH)2 - 50%ZnO
7.1 μm 13 μm
Gomez-Ortiz, N., De la Rosa-Garcia, S.C., Gonzalez-Gomez, W.S., Soria-Castro, M., Quintana, P., Oskam, G.,
Ortega-Morales, B.O. Antifungal coatings based on Ca(OH)2 mixed with ZnO/TiO2 nanomaterials for protection of
limestone monuments. ACS Applied Materials & Interfaces 5 (2013) 1556-1565
without/coating
with/coating
Microbial and bacterial
colonization analysis on the
surface of the rocks
Different concentrations of the coatings
10, 5, 2.5, 1.25, 0.625, 0.312, 0.156, 0.781 mg,
are added in 8 mm of gel perforations
Sterilized plate of 10 x10 cm
Biotest was applied according to CLSI (Clinical & Laboratory Standards Inst).
Diffusion method in agar
3.5 mL of adjusted liquid
suspension are deposited in a
flask with agar PDA or Agar
Mueller Hinton (AMH).
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Microdilution method
Minimum inhibitory concentration (MIC)
Incubation in a
oven at 24°C
Microplates
Control de crecimiento Itraconazol
5 2.5 1.25 0.62 0.31 0.15 0.07 0.03 0.015 0.007 0.003 0.0015
CZ-H MIC
MIC
MIC
MIC
MIC
MIC
ZnO
CZ-ZnO H
CMF and CMB:
Is the minimum
concentration that
prevents the growing
of microorganisms
after been cultivated
in a free medium of
PDA (fungi) or
AMH (bacteria) and
without the coating
(< 3 colonies)
Microbiologic
Replicator Sterilized plate
with the culture
medium
Minimum concentration fungicide (CMF)
Minimum concentration bactericide (CMB)
Fungi and bacteria cultivated with the coating taken from the microplate
Stablish the action mode
fungicidal or fungistatic
bactericidal or bacteriostatic
Structural damage on
Aspergillus niger and
Penicillium oxalicum, when
caused by the coating applied
on the surface of the
calcareous rocks.
The procedure was the same
for MIC
Sterilized plate 24 wells
Glutaraldehyde
Structural damage on fungi
Aspergillus niger
Penicillium oxalicum
Fungi
Bacteria
Levaduriforme
Candida albicans
Escherichia coli Staphylococcus aureus
Microbial and bacterial colonization analysis on the coatings and on the surface of the rocks
Yeast
10 15 20 25 30 35 40 45 50 55 60
CZCZ
5h
4h
2h
P P
c)
b)
PP
P
ZZ Z
P
C
C
CZ
CZCZ
Inte
ns
ida
d R
ela
tiv
a (
u.a
)
CZ
C
Pa)
CZ=Calcium zincate C=Calcite P=Portlandite Z= Zincite
CaCl2 2H2O + 2 ZnO + 2 H2O + 2 NaOH Ca[Zn(OH)3]2 2H2O + 2 NaCl
CZ: retardation of cement hydration; passivation of galvanized steel corrosion in cement pastes or in alkali solutions; slowing anode degradation in Zn/NiOOH batteries, has higher lifecycle decreases precipitation and dissolution of Zn during charge-discharge; as solid base catalyst for the
methanolysis of sunflower for biodiesel.
Hydrated calcium zincate
MC a = 6.384Å, b = 10.967Å, c = 5.759Å; β = 101.92°
Zn (OH)4 Ca(OH)6
Limestone coupons A (Pisté) B (White flagstone Ticul) C (Ticimul)
A. niger P. oxalicum A. niger P. oxalicum A. niger P. oxalicum
Control (untreated) (–)2 (–)2 (–)2 (–)2 (–)2 (–)2
Ca[Zn(OH3)]2·2H2O (+++) (+++) (+++) (+++) (+++) (+++)
Antifungal activity of coatings applied to three different limestone coupons after 21 days of exposure under simulated photoperiod (D/UVL).
Antifungal activity (+++) effective (++) moderate, (+) poor (–) ineffective; superscript indicates the number of days after which the samples were completely covered with fungal colonies.
coated limestone coupons inoculated with A. niger & P. oxalicum.
without coating and before inoculation
Optical microscopy images of the limestone coupons
uncoated control coupons after inoculation with fungi strains
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Antifungal activity of the coatings and the biofilm
formation on the rock surfaces
without/coating Biofilm/coating CZ P. oxalicum +CZ
Biofilm growth on the rock without CZ
(1) Natural limestone without antifungal coating and inoculated with A. niger (2) without antifungal coating and inoculated with P. oxalicum; (3) with antifungal coating and inoculated with A. niger; (4) with antifungal coating and inoculated with P. oxalicum.
X-ray diffraction analysis of the limestone substrates, before and after 21 days of inoculation, with two fungi
A C B
The presence of weddelite is an indicator of the fungal activity
Limestone coupons A, B, C inoculated with A. niger, without and with CZ coatings.
Limestone coupons A, B, C inoculated with P. oxalicum, without and with CZ coatings.
Gómez-Ortíz, N.M., González-Gómez, W.S., De la Rosa-García S.C., Oskam, G., Quintana, P. Soria-Castro, M., Gómez-Cornelio, S., Ortega-Morales, B.O. Antifungal activity of Ca[Zn(OH)3]2 ·2H2O coatings for the preservation of limestone monuments: An in vitro study. Int. Biodeter & Biodegr 91(2014).1-8
Tyoe of
pathogen
Microorganisms Replication MIC (mg/mL) CMF (mg/mL)
CZ ZnO CZ ZnO
Fungi
P. oxalicum
0.312-1.25
Fgt
0.039-0.625
Fgt
-
1.25
Fgc
A. niger 0.156-1.25
Fgt 0.039-1.25
Fgt - -
Yeast C. albicans
0.312-.0.625
Fgt 5.0
Fgt 1.25-10
Fgc 10.0
Fgc
Measurements of CMI and CMF and the action mode
Indicating the initial growing concentration
Fgc = Fungicidal Microorganisms die Fgt = Fungistatic Preventing the growth of fungi
Type of
pathogen Microorganisms
CMI (mg/mL) CMB (mg/mL)
CZ ZnO CZ ZnO Bacteria
Gram
positive
Escherichia coli 1.25
0.156-
1.25
Bct
1.25-10
Bac 2.5-10
Bac
Bacteria
Gram
negative
Staphylococcus
aureus
0.078-
0.625
Bct
0.019-
0.78
Bct
1.25-10
Bac
0.156-10
Bac
Measurements of CMI and CMB and the action mode
Bac = Bactericidal Microorganisms die
Bct = Bacteriostatic Preventing the growth of bacteria
Indicating the initial growing concentration
Gram+ higher susceptibility one cellular membrane Gram– double membrane higher protection
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SEM
Aspergillus niger.
a) Fungal control
b) Conidia
c) CMI of ZnO
(no cell damage or
formation of
hyphaes)
d) CZ after CMI
(no changes)
Morphological effect when fungi grows due to the
presence of CZ and ZnO
SEM
Penicillium oxalicum
a) Fungal control
b) Conidia
c) CMI of ZnO
(cell damage and
conidia germination)
d) ZnO after CMI
shows unusual
protuberances that
grows in the hyphaes
Morphological effect when fungi grows due to the
presence of CZ and ZnO
PATENT Mx/a/2015/004076: Formulaciones y compositos con propiedades
antibacterianas, antimicrobianas, antimicóticas y/o antivirales
All limestone substrates without protective coating, fungal growth and
penetration into the limestone was observed. In addition, it is clearly to
observe the presence of calcium oxalate crystals, and its presence is an
indicator of the fungal activity.
Calcium zinc hydroxide dihydrate coating is well-adhered to all
substrates. The diffusion method in agar of CZ show a high antifungal,
antibacterial and no activity of yeast, also an inhibitory activity of wide
spectra against bacteria Gram-positive, in comparison to ZnO.
therefore for the three limestone substrates with the protective coating,
no fungal growth was observed, illustrating the excellent antifungal
properties of the CZ.
PATENT: Mx/a/2015/004076: Formulaciones y compositos con propiedades
antibacterianas, antimicrobianas, antimicóticas y/o antivirales
in situ (22 d)
ex situ (46d)
in vitro
Ca[Zn(OH)3]2·2H2O
ZnO
Environmental
urban and marine
(3,6,9,12 months)
20 meses
(4/12/2015) 30 meses
(6/10/2016)
Cinvestav-Mérida
Depto Física Aplicada
Dra. Patricia Quintana
Dr. Gerko Oskam
Dr. Juan José Alvarado
Friedrich Schiller Univ. Jena
Dr Carlos Guerrero
Fernando May (Posdoctorado)
Nikté Gómez (Doctorado)
Santiago González (Doctorado)
Montserrat Soria (Doctorado)
Uriel Zagada (Maestría)
Universidad Autónoma
de Campeche
Lab Microbiología
Ambiental y Biotecnología
Dr. Otto Ortega Morales
Centro Investigación
Científica de Yucatán
Unidad Académica Materiales
Dr. Francis Avilés
Collaborations Universidad Juárez Autónoma de Tabasco Lab de Microbiología
Dra. Susana de la Rosa
García y MC Sergio Gómez
Gracias!
Trompetistas, Bonampak