In vitro action of some disinfectants on Paracoccidioides brasiliensis yeast forms Ação "in vitro" de alguns desinfetantes sobre formas leveduriformes de Paracoccidioides brasiliensis
The fungicidal action of sodium hypochlorite (0.3, 1, 2.5, 5 and 10%); formaldehyde (2, 5, and 10%); and ethyl alcohol (70%) on yeast forms of Paracoccidioides brasiliensis Pb 18 and a newly-isolated Goiana strain was described. Contact between the fungus and the disinfectants was maintained for 1,...
| Published in: | Revista do Instituto de Medicina Tropical de São Paulo |
|---|---|
| Main Authors: | , , , , , , , , , |
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
Universidade de São Paulo (USP)
1991
|
| Subjects: | |
| Online Access: | https://doi.org/10.1590/S0036-46651991000100008 https://doaj.org/article/dca82ed2d9a94167b5b7d65eb028ae9e |
| Summary: | The fungicidal action of sodium hypochlorite (0.3, 1, 2.5, 5 and 10%); formaldehyde (2, 5, and 10%); and ethyl alcohol (70%) on yeast forms of Paracoccidioides brasiliensis Pb 18 and a newly-isolated Goiana strain was described. Contact between the fungus and the disinfectants was maintained for 1, 2, 24, 48 and 72 hours at room temperature. Viability was evaluated by the fluorescein diacetate-ethidium bromide treatment, culture in solid and liquid media (36ºC and 26ºC); yeast to mycelial germination at room temperature; and radiometric study of metabolic activity. All concentrations of disinfectants were found to be effective in inactivating Pb 18 and Goiana strains, except for the 1-hour contact with 2% formaldehyde, in which fluorescein diacetate-ethidium bromide treatment was found to reveal 40 and 27% of viable cells, respectively. The yeast to mycelial germination method was considered to reveal faster and similar results as compared to culture in solid and liquid media. Descreveu-se a ação fungicida do hipoclorito de sódio (0,3; 1; 2,5; 5 e 10%); do formaldeído (em solução aquosa a 2,5 e 10%); e álcool etílico a 70,0% sobre formas leveduriformes de 2 cepas de Paraccoccidioides brasiliensis: Pb 18 e cepa Goiana, recentemente isolada. A incubação do fungo e desinfetantes foi realizada à temperatura ambiente por períodos de 1, 2, 24, 48 e 72 horas. A viabilidade foi avaliada pelo tratamento com diacetato de fluoresceína-brometo de etídeo; pela cultura em meios sólidos e líquidos a 36ºC e 26ºC; transformação de levedura em micélio à temperatura ambiente; e estudo radiométrico da atividade metabólica. Todas as concentrações de todos os desinfetantes estudados foram capazes de inativar ambas as cepas, exceto na incubação com formaldeído a 2% por 1 hora, em que o tratamento por diacetato de fluoresceína-brometo de etídeo revelou 40% e 27% de células viáveis, respectivamente, para a cepa Pb 18 e Goiana. A transformação de levedura em micélio foi considerada um método rápido, com resultados semelhantes ao cultivo ... |
|---|