This study focused on the identification of the filamentous fungi associated with soapstone samples exposed to outdoor conditions and the biocidal effect of gamma radiations on isolated fungal populations in Minas Ger...This study focused on the identification of the filamentous fungi associated with soapstone samples exposed to outdoor conditions and the biocidal effect of gamma radiations on isolated fungal populations in Minas Gerais State in Brazil. Two soapstone blocks were placed outdoors under tropical environmental conditions for 12 months. A total of 9 filamentous fungal populations were identified on their surfaces, namely Acremomium （cf.） alternatum, Alternaria alternata, Aspergillusfumigatus, Calcarisporium （cf.） arbuscula, Cladosporium cladosporioides, Curvularia lunata, Epicoccum nigrum, Fusarium equiseti and Penicillium citrinum. The gamma radiation assay was then carried out as a test of biocidal action by exposing all fungal populations to the ionizing radiation. The results showed that only the C. cladosporioides species was resistant to this biocidal agent, since it was able to increase its population post exposure. Scanning electron microscopy images identified the microbial colonization on the soapstone blocks and the stone elementar composition was analyzed by energy dispersive X-ray spectrometry. After treatment, there was no structural and aesthetic alteration in the soapstone samples, and evidencing that gamma radiation can be used as a biocidal agent. However, the resistance of the black fungal population indicates caution in the choice of gamma irradiation as biocidal treatment.展开更多
The CBM （chromoblastomycosis） is a disease caused by dematiaceous fungi, which has the species Fonsecaea pedrosoi as main agent. This fungus is found in warm and moist climates, characteristically found in the amazo...The CBM （chromoblastomycosis） is a disease caused by dematiaceous fungi, which has the species Fonsecaea pedrosoi as main agent. This fungus is found in warm and moist climates, characteristically found in the amazonic lands of the region, where its environmental isolation was once described. This research aimed to identify the healthy population exposed to agent F. pedrosoi in four villages located in the Legal Amazon. In order to clarify the risk factors for allergic immune exposure, a survey was conducted by the technique of delayed skin reaction （IDR） with the metabolic antigen （chromomycin） in 449 healthy individuals. The results showed that 14.9% （67 subjects） were IDR positive, with induration 〉 5 mm. Multivariate analysis with logistic regression for risk factors： living in the village of Z6 Pedro （municipality of Bacabeira in the state of Maranhao, Brazil）,展开更多
The present study aims to evaluate the environmental effect on fungal community composition associated with biodeterioration occurring in stones （soapstone） at two distinct locations in Minas Gerais State, Brazil： ...The present study aims to evaluate the environmental effect on fungal community composition associated with biodeterioration occurring in stones （soapstone） at two distinct locations in Minas Gerais State, Brazil： Congonhas city and Sanctuary of Cara^a. Four collections of fungal communities over one year were obtained from both research sites from the soapstone block surfaces exposed for over two decades. The molecular diversity profile of the fungal community at the two localities was obtained by DGGE （Denaturing Gradient Gel Electrophoresis）, and the genomes of the most representative population were sequenced. DGGE showed the formation of two clusters with filamentous fungal communities. Sequencing of the most representative bands revealed the presence of fungi associated with the biodeterioration of soapstone. In addition, many of the identified species were associated with photobionts that could generate lichens, indicating that environmental characteristics affect the occurrence of filamentous fungi, which leads to biodeterioration of stones. Authors＇ study focused on an environmental variation of an extreme habitat for fungi associated with soapstone in the state of Minas Gerais, Brazil and identified the presence of interesting rock-inhabiting fungal communities including species related to lichens, which can accelerate the deterioration of stones by the production of organic acids.展开更多
文摘This study focused on the identification of the filamentous fungi associated with soapstone samples exposed to outdoor conditions and the biocidal effect of gamma radiations on isolated fungal populations in Minas Gerais State in Brazil. Two soapstone blocks were placed outdoors under tropical environmental conditions for 12 months. A total of 9 filamentous fungal populations were identified on their surfaces, namely Acremomium （cf.） alternatum, Alternaria alternata, Aspergillusfumigatus, Calcarisporium （cf.） arbuscula, Cladosporium cladosporioides, Curvularia lunata, Epicoccum nigrum, Fusarium equiseti and Penicillium citrinum. The gamma radiation assay was then carried out as a test of biocidal action by exposing all fungal populations to the ionizing radiation. The results showed that only the C. cladosporioides species was resistant to this biocidal agent, since it was able to increase its population post exposure. Scanning electron microscopy images identified the microbial colonization on the soapstone blocks and the stone elementar composition was analyzed by energy dispersive X-ray spectrometry. After treatment, there was no structural and aesthetic alteration in the soapstone samples, and evidencing that gamma radiation can be used as a biocidal agent. However, the resistance of the black fungal population indicates caution in the choice of gamma irradiation as biocidal treatment.
文摘The CBM （chromoblastomycosis） is a disease caused by dematiaceous fungi, which has the species Fonsecaea pedrosoi as main agent. This fungus is found in warm and moist climates, characteristically found in the amazonic lands of the region, where its environmental isolation was once described. This research aimed to identify the healthy population exposed to agent F. pedrosoi in four villages located in the Legal Amazon. In order to clarify the risk factors for allergic immune exposure, a survey was conducted by the technique of delayed skin reaction （IDR） with the metabolic antigen （chromomycin） in 449 healthy individuals. The results showed that 14.9% （67 subjects） were IDR positive, with induration 〉 5 mm. Multivariate analysis with logistic regression for risk factors： living in the village of Z6 Pedro （municipality of Bacabeira in the state of Maranhao, Brazil）,
文摘The present study aims to evaluate the environmental effect on fungal community composition associated with biodeterioration occurring in stones （soapstone） at two distinct locations in Minas Gerais State, Brazil： Congonhas city and Sanctuary of Cara^a. Four collections of fungal communities over one year were obtained from both research sites from the soapstone block surfaces exposed for over two decades. The molecular diversity profile of the fungal community at the two localities was obtained by DGGE （Denaturing Gradient Gel Electrophoresis）, and the genomes of the most representative population were sequenced. DGGE showed the formation of two clusters with filamentous fungal communities. Sequencing of the most representative bands revealed the presence of fungi associated with the biodeterioration of soapstone. In addition, many of the identified species were associated with photobionts that could generate lichens, indicating that environmental characteristics affect the occurrence of filamentous fungi, which leads to biodeterioration of stones. Authors＇ study focused on an environmental variation of an extreme habitat for fungi associated with soapstone in the state of Minas Gerais, Brazil and identified the presence of interesting rock-inhabiting fungal communities including species related to lichens, which can accelerate the deterioration of stones by the production of organic acids.
