The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Patricia Sandra Guiamet - One of the best experts on this subject based on the ideXlab platform.
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scopulariopsis sp and fusarium sp in the documentary heritage evaluation of their Biodeterioration ability and antifungal effect of two essential oils
Microbial Ecology, 2016Co-Authors: Paola Lavin, Sandra Gabriela Gomez De Saravia, Patricia Sandra GuiametAbstract:Fungi produce pigments and acids, generating particular local conditions which modify the physicochemical properties of materials. The aims of this work are (i) to investigate bioadhesion, foxing production and biofilm formation by Scopulariopsis sp. and Fusarium sp. isolated from document collections under laboratory conditions; (ii) to verify attack on cellulose fibres and (iii) to study the possibility of reducing fungal growth using natural products. Biofilm formation and extracellular polymeric substance (EPS) production by fungi were demonstrated in laboratory assays and by scanning electron microscopy (SEM) observations. The biocidal activity of two essential oils of Origanum vulgare L. and Thymus vulgaris L. was evaluated using the microatmosphere method. SEM observations showed that these strains were able to attach to paper and form biofilms, causing damage on them, which demonstrates the Biodeterioration ability of these microorganisms. Scopulariopsis sp. and Fusarium sp. isolated from paper books showed the formation of fox-like reddish-brown colour spots, attack to the paper structure and pigment production on aged paper samples. The strains tested produced a decrease in the pH of one unit. This would substantiate the effect of the strains in paper Biodeterioration. The microatmosphere method showed that volatile compounds of the essential oils have antifungal activity.
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an environmental assessment of Biodeterioration in document repositories
Biofouling, 2014Co-Authors: Paola Lavin, S Gomez G De Saravia, Patricia Sandra GuiametAbstract:Experiments were designed (1) to investigate the bioadhesion, biofilm formation, foxing, and micropitting in documentary collections, (2) to assess the risk of Biodeterioration, (3) to investigate the environmental microbial concentration, and (4) to study the influence of environmental factors in Biodeterioration of documentary heritage in three archives. The importance of this work in the field of Biodeterioration of documentary heritage was verified by bioadhesion and biofilm formation by microorganisms isolated from the collections under study. Bacillus sp. and Scopulariopsis sp. isolated from paper books showed considerable evidence of attacking the paper structure and of pigment production, constituting a hazard to the loss of documentary heritage.
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Biodeterioration of funeral sculptures in la recoleta cemetery buenos aires argentina pre and post intervention studies
Colloids and Surfaces B: Biointerfaces, 2013Co-Authors: Paola Lavin, Patricia Sandra Guiamet, Sandra Gabriela Gomez De Saravia, Miguel Crespo, Beatriz Ponce, Christine C GaylardeAbstract:Stone materials exposed to weathering are subject to biological colonization and consequently to biofilm formation, causing Biodeterioration. The color changes on the stone substrates caused by biogenic pigments, mechanical stress on the mineral structure due to extracellular polymeric substances (EPS) and the accumulation of atmospheric pollutants by the biofilm are some of the deteriogenic effects, which modify esthetic and functional aspects of the work. The aim of this study was to determine Biodeterioration and biofilm formation on marble tombstones from La Recoleta Cemetery, Buenos Aires, Argentina. The effect of the biocide benzalkonium chloride on biofilm formation was studied, and a chart produced of the treated tombstones. Pre- and post-intervention microbiological studies, scanning electron microscopy and X-ray dispersion analysis showed a significant decrease of the biofilm flora after treatment. However, algae of the genus Trentepohlia were difficult to eradicate. These studies are a valuable contribution to determine restoration criteria against biofilm formation, to characterize chromatic variations of biological origin on the stone and to formulate conservation and restoration policies.
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essential oils of plants as biocides against microorganisms isolated from cuban and argentine documentary heritage
International Scholarly Research Notices, 2012Co-Authors: Sofia Borrego, Paola Lavin, Patricia Sandra Guiamet, Isbel Vivar, Oderlaise Valdes, Patricia Adriana Battistoni, Sandra Gabriela Gomez De SaraviaAbstract:Natural products obtained from plants with biocidal activity represent an alternative and useful source in the control of Biodeterioration of documentary heritage, without negative environmental and human impacts. In this work, we studied the antimicrobial activity of seven essential oils against microorganisms associated with the Biodeterioration of documentary heritage. The essential oils were obtained by steam distillation. The antimicrobial activity was analyzed using the agar diffusion method against 4 strains of fungi and 6 bacterial strains isolated from repositories air and documents of the National Archive of the Republic of Cuba and the Historical Archive of the Museum of La Plata, Argentina. Anise and garlic oils showed the best antifungal activity at all concentrations studied, while oregano oil not only was effective against fungi tested but also prevented sporulation of them all. Orange sweet and laurel oils were ineffective against fungi. Clove, garlic, and oregano oils showed the highest antibacterial activity at 25% against Enterobacter agglomerans and Streptomyces sp., while only clove and oregano oils were effective against Bacillus sp. at all concentrations studied. This study has an important implication for the possible use of the natural products from plants in the control of Biodeterioration of documentary heritage.
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the quality of air at archives and the Biodeterioration of photographs
International Biodeterioration & Biodegradation, 2010Co-Authors: Sofia Borrego, Paola Lavin, Patricia Sandra Guiamet, Sandra Gomez De Saravia, Patricia Batistini, Michel Garcia, Ivette PerdomoAbstract:The objectives of the paper were to evaluate the microbial prevalence inside the buildings of the Photographic Library of the National Archive of the Republic of Cuba (PLNARC) and of the Historical Archive of the Museum of La Plata (HAMP) and to estimate the levels of microbial contamination on photos stored in these repositories. We have also examined some of the physiological features of fungal and bacterial isolates in order to evaluate their potential for Biodeterioration. A sedimentation method was used for the microbiological sampling of air, while sterile cotton swabs were used for sampling documents. Petri dishes with appropriate selective culture media were used to isolate fungi and bacteria. The cellulolytic, proteolytic, and amylolytic activities and the production of acids and pigments of the fungal isolates were qualitatively determined. The predominant fungal genera in the air of both institutions were Cladosporium and Penicillium, respectively, for PLNARC and HAMP. At both places, the prevalent bacterial isolates were Gram positive. Among the microbial isolates from photos, various fungal and bacterial isolates were capable of degrading starch and protein and also to excrete acids and pigments, which constitute a high potential risk for the Biodeterioration of these documents.
Sandra Gabriela Gomez De Saravia - One of the best experts on this subject based on the ideXlab platform.
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scopulariopsis sp and fusarium sp in the documentary heritage evaluation of their Biodeterioration ability and antifungal effect of two essential oils
Microbial Ecology, 2016Co-Authors: Paola Lavin, Sandra Gabriela Gomez De Saravia, Patricia Sandra GuiametAbstract:Fungi produce pigments and acids, generating particular local conditions which modify the physicochemical properties of materials. The aims of this work are (i) to investigate bioadhesion, foxing production and biofilm formation by Scopulariopsis sp. and Fusarium sp. isolated from document collections under laboratory conditions; (ii) to verify attack on cellulose fibres and (iii) to study the possibility of reducing fungal growth using natural products. Biofilm formation and extracellular polymeric substance (EPS) production by fungi were demonstrated in laboratory assays and by scanning electron microscopy (SEM) observations. The biocidal activity of two essential oils of Origanum vulgare L. and Thymus vulgaris L. was evaluated using the microatmosphere method. SEM observations showed that these strains were able to attach to paper and form biofilms, causing damage on them, which demonstrates the Biodeterioration ability of these microorganisms. Scopulariopsis sp. and Fusarium sp. isolated from paper books showed the formation of fox-like reddish-brown colour spots, attack to the paper structure and pigment production on aged paper samples. The strains tested produced a decrease in the pH of one unit. This would substantiate the effect of the strains in paper Biodeterioration. The microatmosphere method showed that volatile compounds of the essential oils have antifungal activity.
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Biodeterioration of funeral sculptures in la recoleta cemetery buenos aires argentina pre and post intervention studies
Colloids and Surfaces B: Biointerfaces, 2013Co-Authors: Paola Lavin, Patricia Sandra Guiamet, Sandra Gabriela Gomez De Saravia, Miguel Crespo, Beatriz Ponce, Christine C GaylardeAbstract:Stone materials exposed to weathering are subject to biological colonization and consequently to biofilm formation, causing Biodeterioration. The color changes on the stone substrates caused by biogenic pigments, mechanical stress on the mineral structure due to extracellular polymeric substances (EPS) and the accumulation of atmospheric pollutants by the biofilm are some of the deteriogenic effects, which modify esthetic and functional aspects of the work. The aim of this study was to determine Biodeterioration and biofilm formation on marble tombstones from La Recoleta Cemetery, Buenos Aires, Argentina. The effect of the biocide benzalkonium chloride on biofilm formation was studied, and a chart produced of the treated tombstones. Pre- and post-intervention microbiological studies, scanning electron microscopy and X-ray dispersion analysis showed a significant decrease of the biofilm flora after treatment. However, algae of the genus Trentepohlia were difficult to eradicate. These studies are a valuable contribution to determine restoration criteria against biofilm formation, to characterize chromatic variations of biological origin on the stone and to formulate conservation and restoration policies.
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essential oils of plants as biocides against microorganisms isolated from cuban and argentine documentary heritage
International Scholarly Research Notices, 2012Co-Authors: Sofia Borrego, Paola Lavin, Patricia Sandra Guiamet, Isbel Vivar, Oderlaise Valdes, Patricia Adriana Battistoni, Sandra Gabriela Gomez De SaraviaAbstract:Natural products obtained from plants with biocidal activity represent an alternative and useful source in the control of Biodeterioration of documentary heritage, without negative environmental and human impacts. In this work, we studied the antimicrobial activity of seven essential oils against microorganisms associated with the Biodeterioration of documentary heritage. The essential oils were obtained by steam distillation. The antimicrobial activity was analyzed using the agar diffusion method against 4 strains of fungi and 6 bacterial strains isolated from repositories air and documents of the National Archive of the Republic of Cuba and the Historical Archive of the Museum of La Plata, Argentina. Anise and garlic oils showed the best antifungal activity at all concentrations studied, while oregano oil not only was effective against fungi tested but also prevented sporulation of them all. Orange sweet and laurel oils were ineffective against fungi. Clove, garlic, and oregano oils showed the highest antibacterial activity at 25% against Enterobacter agglomerans and Streptomyces sp., while only clove and oregano oils were effective against Bacillus sp. at all concentrations studied. This study has an important implication for the possible use of the natural products from plants in the control of Biodeterioration of documentary heritage.
Paola Lavin - One of the best experts on this subject based on the ideXlab platform.
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scopulariopsis sp and fusarium sp in the documentary heritage evaluation of their Biodeterioration ability and antifungal effect of two essential oils
Microbial Ecology, 2016Co-Authors: Paola Lavin, Sandra Gabriela Gomez De Saravia, Patricia Sandra GuiametAbstract:Fungi produce pigments and acids, generating particular local conditions which modify the physicochemical properties of materials. The aims of this work are (i) to investigate bioadhesion, foxing production and biofilm formation by Scopulariopsis sp. and Fusarium sp. isolated from document collections under laboratory conditions; (ii) to verify attack on cellulose fibres and (iii) to study the possibility of reducing fungal growth using natural products. Biofilm formation and extracellular polymeric substance (EPS) production by fungi were demonstrated in laboratory assays and by scanning electron microscopy (SEM) observations. The biocidal activity of two essential oils of Origanum vulgare L. and Thymus vulgaris L. was evaluated using the microatmosphere method. SEM observations showed that these strains were able to attach to paper and form biofilms, causing damage on them, which demonstrates the Biodeterioration ability of these microorganisms. Scopulariopsis sp. and Fusarium sp. isolated from paper books showed the formation of fox-like reddish-brown colour spots, attack to the paper structure and pigment production on aged paper samples. The strains tested produced a decrease in the pH of one unit. This would substantiate the effect of the strains in paper Biodeterioration. The microatmosphere method showed that volatile compounds of the essential oils have antifungal activity.
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an environmental assessment of Biodeterioration in document repositories
Biofouling, 2014Co-Authors: Paola Lavin, S Gomez G De Saravia, Patricia Sandra GuiametAbstract:Experiments were designed (1) to investigate the bioadhesion, biofilm formation, foxing, and micropitting in documentary collections, (2) to assess the risk of Biodeterioration, (3) to investigate the environmental microbial concentration, and (4) to study the influence of environmental factors in Biodeterioration of documentary heritage in three archives. The importance of this work in the field of Biodeterioration of documentary heritage was verified by bioadhesion and biofilm formation by microorganisms isolated from the collections under study. Bacillus sp. and Scopulariopsis sp. isolated from paper books showed considerable evidence of attacking the paper structure and of pigment production, constituting a hazard to the loss of documentary heritage.
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Biodeterioration of funeral sculptures in la recoleta cemetery buenos aires argentina pre and post intervention studies
Colloids and Surfaces B: Biointerfaces, 2013Co-Authors: Paola Lavin, Patricia Sandra Guiamet, Sandra Gabriela Gomez De Saravia, Miguel Crespo, Beatriz Ponce, Christine C GaylardeAbstract:Stone materials exposed to weathering are subject to biological colonization and consequently to biofilm formation, causing Biodeterioration. The color changes on the stone substrates caused by biogenic pigments, mechanical stress on the mineral structure due to extracellular polymeric substances (EPS) and the accumulation of atmospheric pollutants by the biofilm are some of the deteriogenic effects, which modify esthetic and functional aspects of the work. The aim of this study was to determine Biodeterioration and biofilm formation on marble tombstones from La Recoleta Cemetery, Buenos Aires, Argentina. The effect of the biocide benzalkonium chloride on biofilm formation was studied, and a chart produced of the treated tombstones. Pre- and post-intervention microbiological studies, scanning electron microscopy and X-ray dispersion analysis showed a significant decrease of the biofilm flora after treatment. However, algae of the genus Trentepohlia were difficult to eradicate. These studies are a valuable contribution to determine restoration criteria against biofilm formation, to characterize chromatic variations of biological origin on the stone and to formulate conservation and restoration policies.
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essential oils of plants as biocides against microorganisms isolated from cuban and argentine documentary heritage
International Scholarly Research Notices, 2012Co-Authors: Sofia Borrego, Paola Lavin, Patricia Sandra Guiamet, Isbel Vivar, Oderlaise Valdes, Patricia Adriana Battistoni, Sandra Gabriela Gomez De SaraviaAbstract:Natural products obtained from plants with biocidal activity represent an alternative and useful source in the control of Biodeterioration of documentary heritage, without negative environmental and human impacts. In this work, we studied the antimicrobial activity of seven essential oils against microorganisms associated with the Biodeterioration of documentary heritage. The essential oils were obtained by steam distillation. The antimicrobial activity was analyzed using the agar diffusion method against 4 strains of fungi and 6 bacterial strains isolated from repositories air and documents of the National Archive of the Republic of Cuba and the Historical Archive of the Museum of La Plata, Argentina. Anise and garlic oils showed the best antifungal activity at all concentrations studied, while oregano oil not only was effective against fungi tested but also prevented sporulation of them all. Orange sweet and laurel oils were ineffective against fungi. Clove, garlic, and oregano oils showed the highest antibacterial activity at 25% against Enterobacter agglomerans and Streptomyces sp., while only clove and oregano oils were effective against Bacillus sp. at all concentrations studied. This study has an important implication for the possible use of the natural products from plants in the control of Biodeterioration of documentary heritage.
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the quality of air at archives and the Biodeterioration of photographs
International Biodeterioration & Biodegradation, 2010Co-Authors: Sofia Borrego, Paola Lavin, Patricia Sandra Guiamet, Sandra Gomez De Saravia, Patricia Batistini, Michel Garcia, Ivette PerdomoAbstract:The objectives of the paper were to evaluate the microbial prevalence inside the buildings of the Photographic Library of the National Archive of the Republic of Cuba (PLNARC) and of the Historical Archive of the Museum of La Plata (HAMP) and to estimate the levels of microbial contamination on photos stored in these repositories. We have also examined some of the physiological features of fungal and bacterial isolates in order to evaluate their potential for Biodeterioration. A sedimentation method was used for the microbiological sampling of air, while sterile cotton swabs were used for sampling documents. Petri dishes with appropriate selective culture media were used to isolate fungi and bacteria. The cellulolytic, proteolytic, and amylolytic activities and the production of acids and pigments of the fungal isolates were qualitatively determined. The predominant fungal genera in the air of both institutions were Cladosporium and Penicillium, respectively, for PLNARC and HAMP. At both places, the prevalent bacterial isolates were Gram positive. Among the microbial isolates from photos, various fungal and bacterial isolates were capable of degrading starch and protein and also to excrete acids and pigments, which constitute a high potential risk for the Biodeterioration of these documents.
Ralph Mitchell - One of the best experts on this subject based on the ideXlab platform.
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mechanical properties and durability of hemp lime concretes
Construction and Building Materials, 2014Co-Authors: Rosanne Walker, Sara Pavia, Ralph MitchellAbstract:Abstract Hemp-lime concrete is a sustainable and carbon negative construction material. This paper investigates the effect of binder type on mechanical strength and durability (resistance to freeze–thaw, salt exposure and Biodeterioration). It compares hemp-lime concretes made with a hydrated lime and pozzolan binder to those including hydraulic lime and cement. SEM analysis revealed abundant hydrates at the hemp interface of the strongly hydraulic commercial binder while the lime:pozzolan binders were mostly carbonated. Increasing binder hydraulicity enhances early strength development however, all concretes achieved similar compressive strengths at 1 year irrespective of the binder type. The concretes with lime:pozzolan binders are more sensitive to freeze:thaw action than those with more hydraulic binders. Salt exposure resulted in the precipitation of salt layers in the concrete however, this did not have a detrimental impact on the compressive strength of the concrete at 1 year. The results evidenced that hemp concrete is resistant to Biodeterioration (7 month exposure). Finally, the addition of water retainer improved the early strength development and freeze:thaw resistance of the concrete with lime–pozzolan binder.
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measurement of limestone Biodeterioration using the ca2 binding fluorochrome rhod 5n
Journal of Microbiological Methods, 2005Co-Authors: Christopher J Mcnamara, Thomas D Perry, Kristen A Bearce, G Hernandezduque, Ralph MitchellAbstract:Limestone and marble have been used extensively in the construction of modern and historic buildings. Microbial colonization and growth on these stone structures is common. Microbial deterioration of stone has been assessed by measuring Ca2+ released from the stone, using ion selective electrodes and titration with EDTA. In this study, the calcium binding fluorochrome Rhod-5N was used to measure Ca2+ released from limestone by endolithic bacteria as an indicator of Biodeterioration. In a 17 d flask experiment, Ca2+ released by endolithic bacteria was twice that of uninoculated controls. Rhod-5N is a rapid and accurate method for measuring microbial Biodeterioration of stone.
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Biodeterioration of concrete by the fungus fusarium
International Biodeterioration & Biodegradation, 1998Co-Authors: Timothy E Ford, Neal S Berke, Ralph MitchellAbstract:The bacterial genus Thiobacillus is known for its ability to degrade concrete. A fungus was isolated from concrete samples and identified as a Fusarium species. Our data indicate that fungi also play an important role in the deterioration of concrete. We observed both weight loss and release of calcium when concrete was exposed to our isolate. Fungal degradation proceeded more rapidly than Thiobacillus-mediated degradation. Our study suggests that interaction between fungal metabolites and calcium in the concrete results in the formation of soluble calcium organic complexes.
Etienne Paul - One of the best experts on this subject based on the ideXlab platform.
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laboratory test to evaluate the resistance of cementitious materials to Biodeterioration in sewer network conditions
Materials, 2021Co-Authors: Amr Aboulela, Amaury Buvignier, Cédric Patapy, Matthieu Peyre Lavigne, Marlene Fourre, Maud Schiettekatte, Tony Pons, Orlane Robin, Mansour Bounouba, Etienne PaulAbstract:The Biodeterioration of cementitious materials in sewer networks has become a major economic, ecological, and public health issue. Establishing a suitable standardized test is essential if sustainable construction materials are to be developed and qualified for sewerage environments. Since purely chemical tests are proven to not be representative of the actual deterioration phenomena in real sewer conditions, a biological test–named the Biogenic Acid Concrete (BAC) test–was developed at the University of Toulouse to reproduce the biological reactions involved in the process of concrete Biodeterioration in sewers. The test consists in trickling a solution containing a safe reduced sulfur source onto the surface of cementitious substrates previously covered with a high diversity microbial consortium. In these conditions, a sulfur-oxidizing metabolism naturally develops in the biofilm and leads to the production of biogenic sulfuric acid on the surface of the material. The representativeness of the test in terms of deterioration mechanisms has been validated in previous studies. A wide range of cementitious materials have been exposed to the Biodeterioration test during half a decade. On the basis of this large database and the expertise gained, the purpose of this paper is (i) to propose a simple and robust performance criterion for the test (standardized leached calcium as a function of sulfate produced by the biofilm), and (ii) to demonstrate the repeatability, reproducibility, and discriminability of the test method. In only a 3-month period, the test was able to highlight the differences in the performances of common cement-based materials (CEM I, CEM III, and CEM V) and special calcium aluminate cement (CAC) binders with different nature of aggregates (natural silica and synthetic calcium aluminate). The proposed performance indicator (relative standardized leached calcium) allowed the materials to be classified according to their resistance to biogenic acid attack in sewer conditions. The repeatability of the test was confirmed using three different specimens of the same material within the same experiment and the reproducibility of the results was demonstrated by standardizing the results using a reference material from 5 different test campaigns. Furthermore, developing post-testing processing and calculation methods constituted a first step toward a standardized test protocol.
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Resistance to Biodeterioration of aluminium-rich binders in sewer network environment: Study of the possible bacteriostatic effect and role of phase reactivity
Cement and Concrete Research, 2019Co-Authors: Amaury Buvignier, Cédric Patapy, Matthieu Peyre Lavigne, Etienne Paul, Alexandra BertronAbstract:This paper aims to better understand the mechanisms explaining the superior resistance of calcium aluminate cement (CAC) materials compared to Portland cement (PC) based materials in sewer networks. The bacteriostatic effect of CAC materials on Sulfur Oxidising Bacteria (SOB) is often argued in the literature as a possible mechanism explaining their better resistance. Reactor tests conducted on SOB demonstrated their ability to acclimatise to high aluminium contents. More generally, using a laboratory Biodeterioration protocol reproducing aggressive conditions, the nature of the material (CAC or PC with different slag contents) did not significantly affect the SOB selection. Moreover the CAC materials seemed to favour the development of a higher SOB activity (and so acid production) than PC-based systems, leading to more aggressive conditions. Finally, the resistance of CAC materials to Biodeterioration appeared to be mainly linked to the intrinsic resistance of phases initially present or precipitated during the deterioration process.