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1.
Braz J Microbiol ; 54(3): 1603-1621, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37584891

ABSTRACT

Biofuels are expected to play a major role in reducing carbon emissions in the aviation sector globally. Farnesane ("2,6,10-trimethyldodecane") is a biofuel derived from the synthesized iso-paraffin route wich can be blended with jet fuel; however, the microbial behavior in farnesane/jet fuel blends remains unknown. The chemical and biological stability of blends should be investigated to ensure they meet the quality requirements for aviation fuels. This work aimed at evaluating the behavior of two fungi Hormoconis resinae (F089) and Exophiala phaeomuriformis (UFRGS Q4.2) in jet fuel, farnesane, and in 10% farnesane blend during simulated storage. Microcosms (150-mL flasks) were assembled with and without fungi containing Bushnell & Haas mineral medium for 28 days at a temperature of 20±2°C. The fungal growth (biomass), pH, surface tension, and changes in the fuel's hydrocarbon chains were evaluated. This study revealed thatthe treatment containing H. resinae showed a biomass of 19 mg, 12 mg, and 2 mg for jet fuel, blend, and farnesane respectively. The pH was reduced from 7.2 to 4.3 observed in jet fuel treatment The degradation results showed that compounds with carbon chains between C9 and C11, in jet fuel, and blend treatments were preferably degraded. The highest biomass (70.9 mg) produced by E. phaeomuriformis was in 10% farnesane blend, after 21 days. However, no significant decrease was observed on pH and surface tension measurements across the treatments as well as on the hydrocarbons when compared to the controls. This study revealed that farnesane neither inhibited nor promoted greater growth on both microorganisms.


Subject(s)
Aviation , Biofuels , Biofuels/analysis , Fossils , Hydrocarbons/analysis
2.
Microb Cell ; 9(5): 103-122, 2022 May 02.
Article in English | MEDLINE | ID: mdl-35647176

ABSTRACT

This study has as objectives to determine the concentration and diversity of the air- and dustborne mycobiota in seven National Archive of the Republic of Cuba repositories, and to assess the potential risk of biodeterioration that isolated taxa may have. In the indoor and outdoor environmental microbiological samplings a SAS biocollector was used and the indoor/outdoor (I/O) ratio was determined for each repository. The settled dust was collected during six months. Sørensen's coefficient of similarity (QS) was calculated to compare the isolated taxa among the three studied niches (indoor air, dust, outdoor air). The biodegradation potential of the isolated taxa was determined by semi-quantitative tests. The concentrations in the air of repositories with natural cross-ventilation ranged from 225.2-750.3 CFU m-3, while in the Map library with air-conditioning the concentration was significantly lower. The I/O ratios ranged from 0.1-1.7 revealing different environmental qualities. The maximum settled dust load was 22.8 mg/m2/day with a top fungal concentration of 6000 CFU g-1. 14 and eleven genera were detected in the air and dust respectively with predominance of the genera Aspergillus, Cladosporium and Penicillium. A QS of 0.8 was obtained between the indoor and the outdoor environments with eleven taxa similar evidencing the incidence of outdoors on the indoor mycobiota. The isolated taxa showed several biodeteriogenic attributes highlighting twelve and 14 taxa from indoor air and dust respectively with positive results for the five tests performed. This demonstrates the potential risk that fungal environmental represent for the preserved documentary heritage.

3.
Fungal Biol ; 126(2): 101-112, 2022 02.
Article in English | MEDLINE | ID: mdl-35078581

ABSTRACT

Living organisms can induce deterioration of cultural heritage. Conservation strategies aimed at avoiding damage and aiding restoration, require a comprehensive knowledge of structure, chemical composition, and identity of microorganisms that colonize artworks. The National Theatre of Costa Rica (NTCR), a building with historic architecture, houses several oil paintings from the nineteenth century, some with visible signs of biodeterioration. One of them is a large format painting on canvas called La Danza (size 9.83 × 5.13 m) from 1896 by Italian artist Vespasiano Bignami, located on the ceiling of the theatre's foyer. In the present study, we undertook a physicochemical and microbiological study of La Danza to identify the fungal species that inhabit the artwork and are responsible for the damage observed. Scanning electron microscope (SEM) images and attenuated total reflectance - Fourier transform infrared (ATR-FTIR) spectroscopic data indicated that the canvas material is made of hemp, the binder contains linseed oil and lead white, and a material in the inner face of the canvas is mainly composed of beeswax. Fungi were isolated onto potato dextrose agar (PDA) and carboxymethyl cellulose (CMC) agar, and then identified with molecular (BTUB, nrDNA ITS, and TEF1 regions) and morphological methods. Four isolates belonging to the genera Myxospora, Pestalotiopsis, Ustilago, and aff. Penicillium, were obtained. Qualitative tests showed cellulolytic activity in all isolated specimens, confirming their possible role in biodeterioration of the canvas. Phylogenetic and morphological data revealed a new species of Myxospora we name here as Myxospora theatro sp. nov., in reference to NTCR. The findings broaden the knowledge of fungi capable of inhabiting and damaging cultural heritage. They also provide valuable information to develop strategies for conservation and restoration of oil paintings on canvas.


Subject(s)
Paintings , Penicillium , Costa Rica , Fungi , Paintings/history , Phylogeny
4.
Acta amaz ; 52(3): 264-269, 2022. tab
Article in English | VETINDEX | ID: biblio-1392866

ABSTRACT

The natural durability of the wood is essential for the definition of its use, and this property can be enhanced with the proper chemical treatment of the wood. Thus, the objective of this study was to evaluate the resistance to termites and decay fungi of Jacaranda copaia wood chemically modified through acetylation. Five experimental treatments were assessed: acetylation for 2, 4, 6 and 8 hours and a control (non-acetylated). The acetylation was carried out by immersing wood samples in acetic anhydride at 90 °C. Acetylated and control samples were subjected to the action of xylophagous termites (Nasutitermes sp.) and decaying fungi (Gloeophyllum trabeum and Trametes versicolor). The acetylation process significantly increased the resistance of Jacaranda copaia wood to the attack of the xylophagous organisms. There was no mass loss after exposure to termites of the wood in any of the acetylation treatments, while in the control wood, mass loss was 9.5%. Regarding the decaying fungi, mass loss occurred in all treatments. Acetylation for 6 and 8 hours were the most efficient chemical treatments, increasing the resistance class of the Jacaranda copaia wood to highly resistant.(AU)


A durabilidade natural da madeira é essencial para a definição de seu uso, e essa propriedade pode ser potencializada com o tratamento químico adequado da madeira. Assim, o objetivo deste trabalho foi avaliar a resistência da madeira de Jacaranda copaia modificada quimicamente por acetilação a cupins e fungos apodrecedores. Cinco tratamentos experimentais foram avaliados: acetilação por 2, 4, 6 e 8 horas e um controle (não acetilado). A acetilação foi realizada por imersão das amostras de madeira em anidrido acético a 90°C. Amostras acetiladas e controle foram submetidas à ação de cupins xilófagos (Nasutitermes sp.) e fungos apodrecedores (Gloeophyllum trabeum e Trametes versicolor). O processo de acetilação aumentou significativamente a resistência da madeira de Jacaranda copaia ao ataque dos organismos xilófagos. Não houve perda de massa após exposição aos cupins da madeira em nenhum dos tratamentos de acetilação, enquanto na madeira controle a perda de massa foi de 9,5%. Em relação aos fungos em decomposição, ocorreu perda de massa em todos os tratamentos. Os tratamentos químicos mais eficientes foram os de acetilação por 6 e 8 horas, elevando a classe de resistência da madeira de Jacaranda copaia para altamente resistente.(AU)


Subject(s)
Animals , Biodegradation, Environmental , Isoptera/microbiology , Bignoniaceae/physiology , Acetylation , Wood/physiology , R Factors
5.
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.

6.
Folia Microbiol (Praha) ; 66(5): 797-807, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34131829

ABSTRACT

The research of the microbiological air quality of a building considered a human historical and cultural heritage site by the United Nations Educational, Scientific, and Cultural Organization is fundamental for preventive conservation action, mainly because it identifies cultivable fungal species around the collections and suggests the appropriate treatment choice. This study investigated the air microbiological parameters inside the Nossa Senhora da Conceição Church and identified the population of airborne fungi. Sixty filamentous fungal isolates were detected with ten distinct taxa. The counts of colony forming units (CFUs) performed at 10 different points were in accordance with Brazilian legislation. In addition, the presence of two fungal species was detected colonizing artworks covered with gold leaves: Cladosporium cladosporioides and Aspergillus versicolor. Air quality monitoring inside the church was in accordance with the required Brazilian legislation standards. The composition of the filamentous fungal community included the presence of human fungal pathogens; for this reason, the use of personal protective equipment was recommended during the restoration work. Thus, characterization of the air microbiological parameters helps to preserve not only the building's collection, but also the health of the faithful, conservators-restorers, tourists, and researchers.


Subject(s)
Environmental Microbiology , Mycobiome , Air Microbiology , Aspergillus , Brazil , Cladosporium , Environmental Monitoring , Fungi , History , Humans
7.
Environ Monit Assess ; 192(12): 802, 2020 Dec 01.
Article in English | MEDLINE | ID: mdl-33263150

ABSTRACT

Organotin compounds are applied in several industrial reactions and can present antifungal and antibacterial activities. Incorrect handling and storage practices of biodiesel and diesel-biodiesel blends can lead to microbial development, impacting its final quality. Concerning this problem, this work investigated the antimicrobial action of two organotin catalysts used in biodiesel production with four isolated microroorganisms (Bacillus pumilus, Pseudomonas aeruginosa, Pseudallescheria boydii, and Aureobasidium pullulans) and a pool of microorganisms (ASTM E1259 standard practice). Samples of soybean biodiesel with different concentrations of dibutyl tin dilaurate (catalyst 1) and di-n-butyl-oxo-stannane (catalyst 2) were prepared and added of mineral medium. The pool of microorganisms was inoculated and incubated at 30 °C and final biomass was weighted after 14 days. Thereafter, soybean biodiesel with catalyst 2 was used. Fungal biomass was weighted, and plate count was used to assess bacterial growth. Results show that catalysts 1 and 2 presented no inhibitory activity on the pool of microorganisms evaluated. A slight inhibitory activity was observed for B. pumilus and A. pullulans growth, but not for P. boydii, P. aeruginosa, or the pool of microorganisms. All experiment exhibited acidification higher than sterile control. Infrared analysis show less microbiological degradation products in the tin-protected fuel with ASTM inoculum. These results suggest that these tin-based catalysts show no toxic effect on native microbial population and a slight effect on some isolated microbial population in laboratory scale and for the first time shows that these organotin compounds can be employed safely as biodiesel catalyst. Graphical abstract.


Subject(s)
Anti-Infective Agents , Organotin Compounds , Biofuels/analysis , Environmental Monitoring , Gasoline/analysis , Organotin Compounds/toxicity , Scedosporium
8.
Mycologia ; 112(5): 859-870, 2020.
Article in English | MEDLINE | ID: mdl-32821020

ABSTRACT

Paper-based works of art and documents of cultural importance kept in museums and libraries can show notorious signs of deterioration, including foxing stains, caused by fungal colonization. Some of the main chromophore agents of fungal origin that deteriorate paper and therefore affect paper cultural heritage both aesthetically and structurally are the group of pigments called melanins. Thus, knowledge of the diversity and features of fungal melanins and of the melanization pathways of fungi growing on paper is key to removing these pigments from paper-based works of cultural importance. This review provides an approach about the current knowledge of melanins synthesized by paper-colonizing fungi, their localization in the fungal structures, and their role in the deterioration of paper. This knowledge might contribute to developing new, effective, and sustainable strategies of restoration and conservation of historical documents and works of art based on paper.


Subject(s)
Art , Fungi/growth & development , Fungi/metabolism , Library Materials , Melanins/adverse effects , Melanins/metabolism , Paper , Museums , Pigments, Biological/adverse effects , Pigments, Biological/metabolism
9.
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.

10.
Environ Sci Pollut Res Int ; 25(30): 30410-30424, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30159846

ABSTRACT

Due to their renewable and sustainable nature, biodiesel blends boost studies predicting their stability during storage. Besides chemical degradation, biodiesel is more susceptible to biodegradation due to its raw composition. The aim of this work was to evaluate the deteriogenic potential (growth and degradation) of Pseudallescheria boydii and Meyerozyma guilliermondii in degrading pure diesel (B0), pure biodiesel (B100), and a B10 blend in mineral medium during storage. The biodeterioration susceptibility at different fuel ratios and in BH minimal mineral medium were evaluated. The biomass measurements of P. boydii during 45 days indicated higher biomass production in the B10 blend. The growth curve of M. guilliermondii showed similar growth in B10 and B100. Although there was no significant production of biosurfactant, lipase production was detected in the tributyrin agar medium of both microorganisms. The main compounds identified in the aqueous phase by GC-MS were alcohols, esters, acids, sulfur, ketones, and phenols. The results showed that P. boydii grew at the expense of fuels, degrading biodiesel esters, and diesel hydrocarbons. M. guilliermondii grew in B100 and B10; however, degradation was not detected.


Subject(s)
Ascomycota/physiology , Biofuels/microbiology , Gasoline/microbiology , Biomass , Brazil , Time Factors
11.
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
12.
Microb Ecol ; 71(3): 628-33, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26500067

ABSTRACT

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.


Subject(s)
Antifungal Agents/pharmacology , Fusarium/drug effects , Oils, Volatile/pharmacology , Origanum/chemistry , Plant Oils/pharmacology , Scopulariopsis/drug effects , Thymus Plant/chemistry , Biofilms/drug effects , Fusarium/physiology , Scopulariopsis/physiology
13.
Braz. arch. biol. technol ; 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.

14.
Ciênc. rural ; Ciênc. rural (Online);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.

15.
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
16.
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
17.
Ci. Rural ; 43(4)2013.
Article in Portuguese | VETINDEX | ID: vti-708574

ABSTRACT

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.


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.

18.
Ci. Rural ; 43(4)2013.
Article in Portuguese | VETINDEX | ID: vti-708288

ABSTRACT

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.


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.

19.
Article in Portuguese | LILACS-Express | VETINDEX | ID: biblio-1479346

ABSTRACT

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.


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.

20.
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
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