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1.
rev. udca actual. divulg. cient ; 24(2): e1533, jul.-dic. 2021. tab, graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1361234

ABSTRACT

RESUMEN Las bacterias y los hongos son un riesgo potencial para el material arqueológico y trabajadores de los museos en Lambayeque, Perú. Con el objetivo de cuantificar la microbiología ambiental aislada del museo Tumbas Reales de Sipán, se muestrearon cuatro almacenes, con Agar Nutritivo y Agar Papa Dextrosa, incubándose a 30 °C, en aerobiosis, hasta por 7 días, para bacterias y, hasta por 10 días, para hongos. Se cuantificaron bacterias con un máximo de 2,7x104 UFC cm-2, en las superficies de pisos y paredes; 1,4x103 UFC m-3, en el aire y hongos filamentosos, con un máximo de 7,5x104 UFC cm-2, en las superficies y 9,1x104 UFC m-3, en el aire. Se aislaron e identificaron los géneros de bacterias: Bacillus, Micrococcus, Acinetobacter, Nocardia, Streptococcus, Staphylococcus y Streptomyces y los géneros de hongos filamentosos: Aspergillus, Cladosporium, Circinella, Syncephalastrum, Penicillium, Alternaria, Staphylotrichum, Cercospora, Rhizopus, Cunninghamella, Chrysosporium, Nigrospora, Stachybotrys, Gliocladium y Verticillium.


ABSTRACT Bacteria and fungi are a potential risk to archaeological material and museum workers in Lambayeque, Peru. In order to quantify the isolated environmental microbiology of the Tumbas Reales de Sipán museum, four warehouses were sampled with Nutritive Agar and Papa Dextrose Agar, incubated at 30 °C in aerobiosis for up to 7 days for bacteria and up to 10 days for fungi. Bacteria were quantified with a maximum of 2.7x104 CFU cm-2 on the floor and wall surfaces, 1.4x103 CFU m-3 in the air and filamentous fungi with a maximum of 7.5x104 CFU cm-2 on the surfaces and 9.1x104 CFU m-3 in the air. Bacterial genera were isolated and identified: Bacillus, Micrococcus, Acinetobacter, Nocardia, Streptococcus, Staphylococcus and Streptomyces and the filamentous fungal genera: Aspergillus, Cladosporium, Circinella, Syncephalastrum, Penicillium, Cyrryspunrichum, Cyrrysopositive, Cyrrysylopola Rushingum, Cyrrysophyllizum, Nigrospora, Stachybotrys, Gliocladium and Verticillium.

2.
Entramado ; 16(1): 192-202, ene.-jun. 2020. tab, graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1124735

ABSTRACT

RESUMEN Se evaluó la durabilidad natural de la madera de O, pyramidale en el municipio de Atrato, Chocó. En cada uno de los ambientes: bajo dosel de árboles BDA, libre exposición LE y bajo sombra de plástico negro BS, se empleó un diseño de bloques completamente al azar conformado por tres tratamientos y tres repeticiones de 30 probetas cada uno. Los resultados del análisis de varianza sugieren que no existe diferencia significativa para el contenido de humedad y la pérdida de masa. Se experimentó un aumento en el contenido de humedad de 119,32% y 90,63% de las probetas ubicadas a LE y BS, respectivamente. Basados en estas características, la madera de O. pyramidale se ubica en la categoría poco resistente, por lo que se puede inferir que, no es apta para construcciones que queden en contacto directo con el suelo, donde es afectada por diversos agentes de biodeterioro.


ABSTRACT The natural durability of O, pyramidalewood was evaluated in the municipality of Atrato, Chocó. In each of the environmental conditions: under canopy of UCT trees, free exposure FE and under black plastic shade UBP a completely random block design was used, consisting of three treatments and three repetitions of 30 wood samples each. The results of the analysis of variance suggest that there is no significant difference for moisture content and mass loss. An increase in moisture content of 119.32% and 90.63% of the wood specimens located at LE and BS, respectively, was observed. Based on these characteristics, O. pyramidalewood is located in the low resistance category, so it can be inferred that it is not suitable for constructions in direct contact with the ground, where it is affected by various biodeteriorating agents.


RESUMO A durabilidade natural da madeira O. pyramidalefoi avaliada no munic'pio de Atrato, Chocó. Em cada um dos ambientes: sob uma copa de árvores BDA, exposição livre LE e sob uma sombra de plástico preto BS, foi utilizado um desenho de bloco completamente aleatório, consistindo em três tratamentos e três repetições de 30 espécimes cada um. Os resultados da análise de variância sugerem que não há diferença significativa para o conteúdo de umidade e perda de massa. Um aumento no teor de umidade de 119,32% e 90,63% foi experimentado por peças de teste localizadas no LE e na BS, respectivamente. Com base nestas caracter'sticas, a madeira O. pyramidaleestá na categoria de baixa resistência, pelo que se pode inferir que não é adequada para construções que estejam em contacto directo com o solo, onde é afectada por vários agentes biodeteriorantes.

3.
Bol. micol. (Valparaiso En linea) ; 31(1): 2-18, jun. 2016. tab, graf
Article in Spanish | LILACS | ID: biblio-868807

ABSTRACT

Las especies del género Aspergillus Link constituyen importantes agentes biodeteriorantes de objetos de valor constructivo, cultural y patrimonial. En ambientes laborales, sus propágulos y metabolitos pueden provocar afecciones a la salud humana. Los estudios aeromicológicos pueden contribuir a minimizar el impacto de Aspergillus spp. en el biodeterioro y la calidad de vida. Se han caracterizado de acuerdo a su potencial biodeterió- geno y patogénico representantes de Aspergillus spp. en el aire de depósitos de materiales en tres instituciones patrimoniales cubanas. Las muestras se tomaron empleando un biocolector SAS súper 100. Se evaluó cualitativamente la actividad celulolítica, amilolítica y proteolítica de los aislados; así como la excreción de pigmentos y ácidos orgánicos. Se evaluó el crecimiento a 37°C y la secreción de hemolisinas. Aspergillus spp. constituyó parte considerable de la micobiota aérea viable en los depósitos con 22 especies correspondientes a 12 secciones, las de mayor variabilidad fueron Flavi y Restricti, mientras la primera y la sección Aspergillus fueron las mejor representadas. El 74 por ciento de las cepas mostraron alta capacidad para degradar los compuestos orgánicos evaluados y secretar ácidos, mientras el 34 por ciento excretó pigmentos de amarillo a pardo oscuro, se evidenció un amplio potencial biodeteriorante en general. Más del 30 por ciento de los aislados mostraron ser patógenos oportunistas peligrosos para el hombre al crecer a 37°C, secretar hemolisinas, y presentar un tamaño conidial que posibilita la depositación en alvéolos pulmonares. Las cepas con mayor impacto biodeteriorante y patogénico fueron las correspondientes a las Secciones Flavi, Nigri y la especie Aspergillus fumigatus Fresen.


Species of the genus Aspergillus Link cause damage to objects constructive, cultural and heritage value. In work environments, their propagules and metabolites may cause disorders to human health. Aerobiological studies can help minimize the impact of Aspergillus spp. in the biodeterioration and quality of life. Aspergillus spp. strains present in the air of the repositories in three Cuban heritage institutions were characterized according to their biodeteriogenic and pathogenic potential. Each isolated was classified taxonomically, cellulolytic, amylolytic and proteolytic activity as well as excretion of pigments and organic acids was evaluated. The capacity to grow at 37°C and secrete hemolysins was qualitatively evaluated. Aspergillus spp. was significant portion of viable air micobiota in the three repositories with 22 species corresponding to 12 sections, most variability were Flavi and Restricti, while the first section and Aspergillus were the best represented. The 74 percent of the strains showed high ability to degrade organic compounds evaluated and secrete acids, while 34 percent excreted pigments from yellow to dark brown, evidenced a broad biodeteriogenic potential in general. More than 30 percent of the isolates were shown to be dangerous opportunistic pathogens for humans to grow at 37°C, secrete hemolysin, and present a conidial size which enables the deposition pulmonary alveoli. Strains higher biodeteriogenic and pathogenic impact were those corresponding to the Flavi, Nigri sections and the species Aspergillus fumigatus Fresen.


Subject(s)
Humans , Aspergillus/classification , Aspergillus/growth & development , Aspergillus/pathogenicity , Biodegradation, Environmental , Cellulose , Hydrolysis , Cuba , Culture Media , Coloring Agents/toxicity , Mycobiome , Plant Components, Aerial
4.
Braz. arch. biol. technol ; 56(3): 475-484, May-June 2013. ilus, tab
Article in English | LILACS | ID: lil-679195

ABSTRACT

Thermoplastics, poly vinyl chloride and low-density polyethylene were treated in the presence of indigenously developed bacterial consortium in laboratory and natural conditions. The consortium was developed using four bacteria, selected on the basis of utilization of PVC as primary carbon source, namely P. otitidis, B. aerius, B. cereus and A. pedis isolated from the plastic waste disposal sites in Northern India. The comparative in-vitro treatment studies as revealed by the spectral and thermal data, illustrated the relatively better biodegradation potential of developed consortium for PVC than the LDPE. Further, the progressive treatments of both the thermoplastics were conducted for three months under natural conditions. For this purpose, bioformulation of consortium was prepared and characterized for the viability up to 70 days of storage at 25±1ºC. The consortium treated polymer samples were monitored through SEM and FT-IR spectroscopy. Analytical data revealed the biodeterioration potential of the developed consortium for PVC and LDPE, which could help in disposing the plastic waste.

5.
Ciênc. rural ; 43(4): 623-630, abr. 2013. ilus, tab
Article in Portuguese | LILACS | ID: lil-669376

ABSTRACT

Objetivou-se avaliar o emprego de ensaios de dureza Rockwell na caracterização da biodeterioração das madeiras de Simarouba amara (marupá), Cariniana micrantha (jequitibá) e Dipteryx odorata (cumaru), submetidas ao ataque dos fungos apodrecedores Trametes versicolor (podridão branca) e Gloeophyllum trabeum (podridão parda). Para tanto, corpos de prova de cada espécie amazônica foram submetidos a ensaios de apodrecimento acelerado, de acordo com a ASTM D2017 (2005), durante 20 semanas. A caracterização da dureza Rockwell foi realizada semanalmente até a 4ª semana e, posteriormente, a cada duas semanas, até a 20ª semana. Adicionalmente, foram determinadas as perdas de massa, conforme critérios estabelecidos pela ASTM D2017 (2005). Quanto aos resultados, destaca-se que a dureza Rockwell pode ser empregada como ferramenta principal na caracterização da biodeterioração da madeira, sendo sensível na predição dos estágios iniciais. Dentre as madeiras amazônicas, o cumaru apresentou a maior resistência natural aos fungos apodrecedores. Com relação aos fungos, a podridão parda atacou mais intensamente as três madeiras amazônicas.


This study aimed to evaluate the use of Rockwell hardness in the characterization of the biodeterioration of Simarouba amara (marupá), Cariniana micrantha (jequitibá) e Dipteryx odorata (cumaru) woods, which were submitted to decay fungi Trametes versicolor (white rot) and Gloeophyllum trabeum (brown rot). For this purpose, specimens of each Amazon species were submitted to decay fungi, according to ASTM D2017 (2005). The characterization of the Rockwell hardness was performed weekly until the fourth week, and then every two weeks until the twentieth week. Additionally, it was determined the mass loss, according to criteria established by ASTM D2017 (2005). The results indicated that the Rockwell hardness can be used as a primary tool in the characterization of the biodeterioration of wood, being sensitive in predicting the early stages. Among the Amazon woods, cumaru wood showed a greater natural resistance to decay fungi. With respect to decay fungi, brown rot more intensely attacked the three Amazon woods.

6.
Univ. sci ; 18(1): 51-63, ene.-abr. 2013. ilus, tab
Article in English | LILACS | ID: lil-677559

ABSTRACT

Se compararon química y microbiológicamente morterosde Bogotá, Villa de Leyva y Barichara. Las muestras seanalizaron por espectrometría de absorción y emisión atómica,espectroscopia infrarroja con transformada de Fourier,difracción de Rayos X, microscopía electrónica de barrido yespectroscopia por dispersión de energía. Se encontraron óxidosde silicio, aluminio, calcio, hierro, magnesio, yeso, weddellita,despuljosita, cuarzo, berlinita, carbonatos, mica, feldespatos,silicatos, sales de nitratos, sulfitos y compuestos orgánicos.A su vez, se hallaron partículas irregulares entre 10, 50 y 100µm y fibras de tipo orgánico de 20 µm. Se realizó el conteo deunidades formadoras de colonias por el método de dilucionespara identificar microorganismos fúngicos. Se identificaron lossiguientes géneros Aspergillus, Penicillium, Alternaria, Fusarium,Mucor y Syncephalastrum. La muestra de Bogotá presentó el mayornúmero de UFC/mL y el mayor porcentaje de humedad relativa.La concentración de hongos en esta muestra, a diferencia delas de Villa de Leyva y de Barichara, causó la degradación de lamayoría de los metales identificados. Esta comparación químicay microbiológica propone un plan eficaz de intervención paraeliminar y prevenir el biodeterioro en apoyo a la conservación deobras patrimoniales...


Mortars from Bogotá, Villa de Leyvaand Barichara were compared chemically andmicrobiologically. We analyzed the samples using atomicabsorption and emission spectrometry, Fourier-transforminfrared spectroscopy, X-ray diffraction, scanningelectron microscopy and energy dispersive spectroscopy.Oxides of silicon, aluminum, calcium, iron, magnesium,gypsum, weddellite, despujolsite, quartz, berlinite,carbonate, mica, feldspars, silicates, nitrate salts, sulfites,and organic compounds were identified. In addition,irregular particles between 10, 50 an 100 µm werefound, as well organic fibers of 20 µm. Was performeda CFU count using a dilution method to identify fungalmicroorganisms and found following genera Aspergillus,Penicillium, Alternaria, Fusarium, Mucor and Syncephalastrum.The mortar sample taken in Bogotá presented thehighest number of CFU/mL and the highest percentageof relative humidity. The concentration of fungi in thissample, unlike those from Villa de Leyva and Barichara,caused degradation in most of the metals identified.This chemical and microbiological comparison proposesan effective plan of action to eliminate and preventbiodeterioration in support of the conservation ofheritage constructions...


As amostras foram analisadas por espectrometria deemissão e espectroscopia de absorção atômica, infravermelhocom transformada de Fourier, difração de raios X, microscopiaeletrônica de varredura e espectroscopia de energia dispersiva.Foram identificados óxidos de silício, alumínio, cálcio, ferro,magnésio, gesso, weddellita, despuljosita, quartzo, berlinita,carbonato, mica, feldspato, silicatos, sais de nitratos, sulfitos, ecompostos orgânicos. Partículas irregulares entre os 10, 50 e 100µm foram encontradas bem como fibras de tipo orgânico de20 µm. Realizou-se uma contagem CFU usando um método dediluição para identificar microorganismos fúngicos e encontrousefungos dos gêneros Aspergillus, Penicillium, Alternaria, Fusarium,Mucor e Syncephalastrum. A amostra de Bogotá apresentou o maiornúmero de UFC/mL e umidade relativa do ar. A maior presençade fungos desta amostra, ao contrário das amostras da Villa deLeyva e Barichara, causou degradação na maioria dos metaisidentificados. Esta comparação química e microbiológica podesugerir um plano de ação eficaz para a eliminação e prevenção dabiodegradação e assim preservar obras patrimoniais.Departamento de Química, Facultad de Ciencias. PontificiaUniversidad Javeriana. Bogotá, D.C., Colombia.Departamento de Microbiología, Facultad de Ciencias. PontificiaUniversidad Javeriana. Bogotá, D.C., Colombia.Departamento de Biología, Facultad de Ciencias. PontificiaUniversidad Javeriana. Bogotá, D.C., Colombia.Departamento de Arquitectura, Facultad de Arquitectura y Diseño.Pontificia Javeriana. Bogotá, D.C., Colombia.Received: 15-12-2012 Accepted: 02-02-2013 Published on line: 28-02-2013 Edited by Alberto Acosta mUniversitas Scientiarum, Journal of the Faculty of Sciences, Pontificia Universidad Javeriana, is licensed under the Creative Commons 2.5 of Colombia: Attribution - Noncommercial - No Derivative...


Subject(s)
Biodegradation, Environmental , Microbiology/classification , Microbiology/history
7.
Rev. luna azul ; (36): 247-284, ene.-jun. 2013. ilus, tab
Article in Spanish | LILACS | ID: lil-677407

ABSTRACT

Los monumentos pétreos declarados como patrimonio histórico son deteriorados a través del tiempo por efecto de agentes físicos, químicos y medioambientales. Estos últimos dependen en gran medida de la ubicación geográfica del inmueble, dichos agentes son: el régimen de vientos que desgasta la roca erosionándola; temporadas de lluvia que al contener sales disueltas causan corrosión por reacciones químicas de estas con la matriz del material calcáreo solubilizando el carbonato de calcio el cual es su principal componente; radiación solar durante todo el año causante de decoloramiento; humedad que permite el establecimiento de formas de vida. Las actividades antropogénicas que no son amigables con el ambiente son otro factor determinante, las emisiones de gases vehiculares por ejemplo, deterioran en gran medida los monumentos de piedra antiguos por ser agentes ácidos altamente corrosivos. Se crean así las condiciones para el establecimiento y proliferación de organismos vivos en la piedra tales como bacterias, algas, hongos, líquenes y plantas que por ser invasivos y colonizadores causan biodeterioro. Dado que los metabolismos de estas especies involucran el consumo de sustratos químicos orgánicos e inorgánicos presentes en la roca, son otro factor que va en detrimento de la estabilidad, durabilidad, y apariencia estética de la misma.


Stony monuments declared as cultural world heritage are deteriorated through the years because of physical, chemical and environmental agents which depend largely on their geographic location. Among these agents are: gust of, winds that wear away the stone eroding it; rainy seasons which bring dissolved salts and cause corrosion because of their chemical reaction with the calcareous material matrix which solubilizes calcium carbonate which is their main component; because of solar radiation all through the year stones lose their color; high humidity allows plants and living forms to grow. Anthropogenic activities which are not environmentally friendly are other important factor: vehicle gas emissions, for example, deteriorate greatly old stone monuments because they are highly corrosive acids. This way, optimal conditions are created for fungi, algae, bacteria, lichens and plants which are invasive and colonizing to live on the stone surface and cause biodeterioration. Since metabolisms of these species involve consumption of inorganic substrates that are present in the stones, they become another factor affecting monument's durability, stability, and aesthetic appearance.


Subject(s)
Humans , Biodegradation, Environmental , Chemical Reactions , Corrosion
8.
Rev. colomb. biotecnol ; 14(1): 108-120, ene.-jun. 2012. ilus, graf, tab
Article in Spanish | LILACS | ID: lil-656944

ABSTRACT

Se ha buscado y seleccionado sistemáticamente una proteasa que pudiese ser usada en la eliminación "limpia" de encolantes sobre soportes documentales con valor de patrimonio histórico de forma eficiente y económica, a partir de la colección de hongos filamentosos del Archivo de Bogotá. De 74 morfotipos viables evaluados sobre placas selectivas, 32 morfotipos presentaron formación de halos de hidrólisis evidentes sobre placas diferenciales. De ellos, se evaluó el perfil isoenzimático de 8 morfotipos provenientes de muestreos documentales directos y de 2 morfotipos proteolíticos promisorios provenientes de un trabajo previo. Los 10 morfotipos seleccionados fueron representativos de los géneros Penicillium, Stachybotrys, Chaetomium, y Eladia. Luego de inducir la producción de proteasas extracelulares en medios líquidos diferenciales bajo tres fases de fermentación, se realizaron isoelectroénfoques analíticos tendientes a la observación de isoformas en el gradiente de pH establecido (3.0-10.0). Solo los morfotipos 8D (Chaetomium sp.) y 21D (Eladia saccula) presentaron una isoforma alcalina extrema, de puntos isoeléctricos 8.5 y 8.8, respectivamente, susceptible de selección con miras a su purificación y caracterización parcial de forma económica y eficiente. Los demás morfotipos, representativos de los géneros Penicillium sp., y Stachybotrys sp., presentaron unicamente isoformas proteolíticas en el rango acido de pH con puntos isoeléctricos que oscilan entre 4.0 y 5.0.


Studies on a protease as an efficient, environmental friendly and relatively economical remover of residual proteins for historical valuable documents were performed and was selected for this work, from the filamentous fungi collection of the Bogota Archive. 32 morphotypes of 74 evaluated show hydrolytic activities over differential solid media. From them, 8 morphotypes obtained directly from documental samples and representative of the genera Penicillium and Stachybotrys were selected and their isoenzyme profile were tested. Also 2 previous morphotypes with promisorius proteolytic activities and representative of the genera Chaetomium and Eladia were analysed. Extracelullar proteases production was induced in differential liquid media on three fermentation steps and analitycal isoelectrofocusing were performed over pH 3.0-10.0 ranges. Only the morphotypes 8D (Chaetomium sp.), and 21D (Eladia sp.), showed an alkaline isoform with pIs 8.5 and 8.8, respectly, suceptible of selection for its purification and characterization through efficient and economical way. The others morphotypes only showed acid isoforms with pIs in the range of 4.0 and 5.0.


Subject(s)
Biodegradation, Environmental , Chaetomium , Isoelectric Point , Paper , Penicillium , Stachybotrys , Fermentation , Filing
9.
Ciênc. rural ; 41(8): 1369-1374, Aug. 2011. ilus, tab
Article in Portuguese | LILACS | ID: lil-596952

ABSTRACT

O conhecimento acerca da resistência dos compostos ligno-celulósicos ao ataque de microrganismos é primordial para servir de base à prevenção da deterioração e a correta destinação de emprego do material. Nesse sentido, avaliou-se a resistência natural a fungos apodrecedores de painéis aglomerados confeccionados com partículas de madeira (Eucalyptus grandis) e/ou bambu (Bambusa vulgaris). Foram produzidas, em laboratório, chapas aglomeradas nas dimensões 50x50x0,95cm e massa específica pré-estabelecida em 0,70g cm-3, nas proporções de 100:0, 75:25, 50:50, 25:75 e 0:100 de madeira e bambu, respectivamente. A massa de partículas representou 91 por cento da massa seca de cada painel, sendo, o restante, formado pelo adesivo ureia-formaldeído (8 por cento) e parafina (1 por cento). Para determinação da resistência natural ao ataque de fungos xilófagos, os painéis foram testados em laboratório e utilizados os fungos Gloeophyllum trabeum (podridão parda) e Trametes versicolor (podridão branca), de acordo com a ASTM D 2017 (2005). Quanto aos resultados, foi observado que os painéis confeccionados com mistura de partículas de madeira e bambu apresentaram menor resistência ao ataque dos fungos apodrecedores. Painéis que utilizaram apenas bambu ou madeira apresentaram resistência biológica semelhante. Dentre os fungos, T. versicolor atacou mais severamente os painéis.


The knowledge about lignocellulosic compounds strength to the attack of microorganisms is essential for preventing deterioration and also for knowing the correct usage of the material. Accordingly it was evaluated the natural resistance of wood panels made of particles of wood (Eucalyptus grandis) and/or bamboo (Bambusa vulgaris) to decay fungi. Particleboards were produced in laboratory, each of them with dimensions 50x50x0.95cm and density pre-set at 0.70g cm-3, in proportions of 100:0, 75:25, 50:50, 25:75 and 0:100 of wood and bamboo, respectively. The particles mass represented 91 percent of the dry mass of each panel while the remainder was formed by the urea-formaldehyde adhesive (8 percent) and paraffin (1 percent). The panels were tested in the laboratory and Gloeophyllum trabeum (brown rot) and Trametes versicolor (white rot) were used to determine the natural resistance to attack by wood decay fungi. It was observed that panels which were made with a mixture of particles of wood and bamboo were less resistant to attack by decay fungi. Panels that were made from bamboo or wood only showed similar biological resistance. Among fungi, T. versicolor was the one that attacked panels more severely.

10.
Electron. j. biotechnol ; 13(6): 1-2, Nov. 2010. ilus, tab
Article in English | LILACS | ID: lil-591905

ABSTRACT

Mastic, one of the best natural varnishes, is frequently used as protective and finishing layer or as component of oleo-resinous media in paintings, both in the past and currently. However, this resin is affected by complex deterioration processes which can change its characteristics and thus the visual aspect of works of art. The alteration processes caused by radiation have been widely studied, but there is a lack of information on the biodeterioration of this natural product. In this paper, fungi from collections as well as from oil paintings of the Fine Arts Museum of Granada (Spain) were inoculated onto slides covered with mastic. The samples, after an incubation period of 15 days, were analysed by gas chromatography-mass spectrometry (GC-MS) to identify the chemical changes undergone, and a visual monitoring of the samples was performed to determine the formation of mycelia onto solidified resins. Major changes were detected in Chrysonilia sitophila, Phoma herbarum, and P. chrysogenum, showing evidence of alteration processes caused or favoured by these microorgamisms.


Subject(s)
Fungi , Paint/microbiology , Triterpenes/analysis , Biodegradation, Environmental , Gas Chromatography-Mass Spectrometry , Paintings
11.
Electron. j. biotechnol ; 13(3): 6-7, May 2010. ilus, tab
Article in English | LILACS | ID: lil-577101

ABSTRACT

Since the middle of the XIX century, when dammar became popular in Occident, this natural resin is one of the most used in art painting techniques as final protective coating (varnish) as well as a component of pictorial media. The present work is the first approach to the study of the microbiological biodeterioration of this artistic material, which can seriously affect the appearance and integrity of works of art when bad conservation conditions -especially high humidity levels- take place. 12 microorganisms, fungi and bacteria, came from collection and from oil paintings affected by biodeterioration patterns, were inoculated on test specimens prepared with varnish dammar. These were incubated and analyzed by GC-MS to determine both the microbiological capacity of growth and chemical alteration on the resin. Some of the studied microorganisms have shown patterns of deterioration similar to those found in works dedicated to natural or accelerated photochemical ageing of triterpenoid varnishes.


Subject(s)
Oils/analysis , Biodegradation, Environmental , Paint/microbiology , Resins, Plant/analysis , Terpenes/analysis , Art , Fungi , Gas Chromatography-Mass Spectrometry
12.
Acta amaz ; 32(4)2002.
Article in Portuguese | LILACS-Express | LILACS, VETINDEX | ID: biblio-1454917

ABSTRACT

The durability of the stem of Bactris gasipaes Kunth (Peach palm) was evaluated in field tests in a forest and in an urban environment, as well as in laboratory conditions. Five trees with spines and five trees without spines from the Tabatinga population (Putumayo landrace) were used in the experiment. Disks approximately 25-30cm thick were taken from the butt, middle and top portions of each tree and distributed at random in forest area near the INPA Peach Palm Germoplasm Bank (2°38'S60°03'W). The disks were checked every three months for 18 months for susceptibility to fungi. In the urban environment each disk was halved to remove the center and each half was distributed at random, one in a concave and the other in a convex position, on a wooden framework in an area near the CPPF/INPA, Manaus, and checked every 2 months for one year. In the forest environment the coating of the disks was susceptible to the fungi Hymenogramme javanensis Mont. & Berk. and Hypoxylon rubiginosum (Pers.: Fr.) Fr. In the urban environment the wood was highly susceptible to the fungi Lenzites striata (Swart.: Fr.) Fr., Lenzites sp, Porostereum amethysteum Hjortst.& Ryv. and Stereum strigoso-zonatum (Sch.) G. H. Cunn. In laboratory conditions the peach palm wood showed great resistance to the fungi Lenzites trabea Pers.: Fr., Polyporus fumosus Pers.: Fr. and Pycnoporus sanguineus (L.: Fr.) Murr.


A durabilidade da madeira de Bactris gasipaes Kunth (pupunha) face aos fungos foi avaliada em ambiente florestal e urbano e em condições de laboratório. Foram utilizadas, cinco árvores com espinhos e cinco sem espinhos da população Tabatinga, raças Putumayo, sendo retirados discos de 25-30cm da base, meio e do topo de cada pupunheira e colocados em uma área florestal próxima ao Banco Ativo de Germoplama de B. gasipaes (2°38'S, 60°03'W). Os discos foram inspecionados trimestralmente, para acompanhar o processo de biodeterioração da madeira causado por fungos durante dezoito meses. No ensaio em ambiente urbano, as amostras do estipe foram distribuídas, uma na posição côncava e outra na convexa, sobre uma estrutura de madeira localizada em uma área próxima da CPPF do Campus do INPA, Manaus e inspecionadas bimestralmente por um ano. Em ambiente florestal, o revestimento dos discos mostrou-se suscetível aos fungos Hymenogramme javanensis Mont. & Berk. e Hypoxylon rubiginosum (Pers.: Fr.) Fr.. Em ambiente urbano, a madeira apresentou alta susceptibilidade a Lenzites striata (Swart.: Fr.) Fr. e a Lenzites sp. e o revestimento a Porostereum amethysteum Hjortst. & Ryv. e a Stereum strigoso-zonatum (Sch.) G. H. Cunn.. Em condições de laboratório, a madeira da pupunheira demonstrou alta resistência aos fungos Lenzites trabea Pers.:Fr., Polyporus fumosus Pers.:Fr. e Pycnoporus sanguineus (L.:Fr.) Murr.

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