Base de dados : LILACS
Pesquisa : B01.300.381.081.170 [Categoria DeCS]
Referências encontradas : 101 [refinar]
Mostrando: 1 .. 10   no formato [Detalhado]

página 1 de 11 ir para página                         

  1 / 101 LILACS  
              next record last record
seleciona
para imprimir
Fotocópia
Texto completo
Id: biblio-1291803
Autor: Matias, Maria Helena IHA; Okada, Isaura Akemi; Briganti, Rita de Cássia; Oliveira, Maria Aparecida de; Cruz, Marcelo Ferreira da.
Título: Incidência de aflatoxinas B1, B2, G1 e G2 em amendoins / Incidence of aflatoxins B1, B2, G1 and G2 in peanuts
Fonte: Rev. Inst. Adolfo Lutz;79(Único):1-7, 31 mar. 2020. tab, graf.
Idioma: pt.
Resumo: Micotoxinas são substâncias tóxicas produzidas por fungos e encontradas nos alimentos. As micotoxinas mais tóxicas são as aflatoxinas, produzidas, principalmente por Aspergillus flavus. Estudos realizados no país demonstraram alta incidência dessas micotoxinas em produtos de amendoim, que representa risco à saúde da população. O objetivo do estudo foi avaliar a incidência de aflatoxinas B1, B2, G1 e G2 em amostras de amendoins comercializados na região Nordeste do Estado de São Paulo nos períodos de 1994-2001 e 2016-2017. O método utilizado para analisar as amostras no primeiro período foi extração líquido-líquido e cromatografia em camada delgada e no segundo foi utilizando colunas de imunoafinidade, cromatografia líquida com derivatização pós- coluna e detector por fluorescência. No levantamento de 1994-2001 das 82 amostras, 39% tiveram contaminação de aflatoxinas variando de 11 a 1556 µg/kg com 37% das amostras contendo níveis maiores que 20 µg/kg, enquanto na pesquisa de 2016-17, das 56 amostras, 38% apresentaram contaminação destas toxinas variando de 0,09 a 60,40 µg/kg com 13% das amostras contendo níveis maiores que 20 µg/kg. Os resultados dos dois períodos estudados indicam que houve uma diminuição na incidência e nível das aflatoxinas estudadas, embora esta contaminação em amendoim permaneça um problema de saúde pública. (AU)

Mycotoxins are toxic compounds produced by fungi found in food. The most toxic mycotoxins are the aflatoxins produced mainly by Aspergillus flavus . Studies carried out in Brazil showed a high incidence of these mycotoxins in peanut products, a fact that represents public health problems. The aim of the study was to evaluate aflatoxins B1, B2, G1, and G2 in samples of peanuts sold in cities of the Northeast of the State of São Paulo in the period from 1994 to 2001 and from 2016 to 2017. The samples of the first period were analyzed using liquid-liquid extraction and thin-layer chromatography and the second using immunoaffinity columns, post-column derivative liquid chromatography and fluorescence detector. In the 1994-2001 survey, among 82 samples, 39% presented aflatoxins contamination ranging from 11 to 1556 µg/kg with 37% with levels greater than 20 µg/kg whereas, in the 2016-17 survey, 38% of the 56 samples presented contamination of aflatoxins ranging from 0.09 to 60.40 µg/kg and 7 samples 13% containing aflatoxins levels higher than 20 µg/kg. The results indicated there was a decrease in the incidence and level of aflatoxins, but the contamination of aflatoxins in peanuts remains a public health problem. (AU)
Descritores: Arachis
Aspergillus flavus
Substâncias Tóxicas
Aflatoxinas
Micotoxinas
-Contaminação de Alimentos
Responsável: BR91.2 - Centro de Documentação


  2 / 101 LILACS  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
Id: biblio-843149
Autor: Lahouar, Amani; Marin, Sonia; Crespo-Sempere, Ana; Saïd, Salem; Sanchis, Vicente.
Título: Efectos de la temperatura, la actividad de agua y el tiempo de incubación en el crecimiento fúngico y la producción de aflatoxina B1 por aislados toxicogénicos de Aspergillus flavus en sorgo / Effects of temperature, water activity and incubation time on fungal growth and aflatoxin B1 production by toxinogenic Aspergillus flavus isolates on sorghum seeds
Fonte: Rev. argent. microbiol;48(1):78-85, mar. 2016. graf, tab.
Idioma: en.
Resumo: Sorghum, which is consumed in Tunisia as human food, suffers from severe colonization by several toxigenic fungi and contamination by mycotoxins. The Tunisian climate is characterized by high temperature and humidity that stimulates mold proliferation and mycotoxin accumulation in foodstuffs. This study investigated the effects of temperature (15, 25 and 37 °C), water activity (a w, between 0.85 and 0.99) and incubation time (7, 14, 21 and 28 d) on fungal growth and aflatoxin B1 (AFB1) production by three Aspergillus flavus isolates (8, 10 and 14) inoculated on sorghum grains. The Baranyi model was applied to identify the limits of growth and mycotoxin production. Maximum diameter growth rates were observed at 0.99 a w at 37 °C for two of the isolates. The minimum a w needed for mycelial growth was 0.91 at 25 and 37 °C. At 15 °C, only isolate 8 grew at 0.99 a w. Aflatoxin B1 accumulation could be avoided by storing sorghum at low water activity levels (≤0.91 a w). Aflatoxin production was not observed at 15 °C. This is the first work on the effects of water activity and temperature on A. flavus growth and AFB1 production by A. flavus isolates on sorghum grains.

El sorgo, que se consume en Túnez como alimento humano, puede sufrir la colonización severa de varios hongos toxicogénicos, con la consiguiente bioacumulación de micotoxinas. Además, el clima de Túnez, caracterizado por las altas temperaturas y humedad, estimula el crecimiento fúngico y la acumulación de micotoxinas en los productos alimenticios. Este estudio investigó los efectos de la temperatura (15, 25 y 37 °C), la actividad de agua (a w) (entre 0,85 y 0,99) y el tiempo de incubación (7, 14, 21 y 28 días) sobre el crecimiento y la producción de aflatoxina B1 (AFB1) de 3 aislados de Aspergillus flavus (designados como 8, 10 y 14) que se inocularon sobre granos de sorgo. El modelo Baranyi se aplicó para identificar los límites del crecimiento y la producción de micotoxinas. Las tasas máximas de crecimiento para 2 de los aislados se observaron en la combinación 0,99 a w y 37 °C. La a w mínima necesaria para el crecimiento del micelio fue de 0,91 a 25 °C y 37 °C. A 15 °C, solo el aislado 8 creció a 0,99 a w, pero fue incapaz de producir la aflatoxina B1. Es posible evitar la acumulación de aflatoxina B1 en el sorgo almacenándolo a baja actividad de agua (≤ 0,91 a w). Este es el primer trabajo que ha estudiado el efecto de la actividad del agua y la temperatura sobre el crecimiento de aislados de A. flavus y su producción de aflatoxina B1 en granos de sorgo.
Descritores: Aspergillus flavus/crescimento & desenvolvimento
Aflatoxina B1/isolamento & purificação
Aflatoxina B1/análise
Umidade/efeitos adversos
Micotoxinas/análise
-Temperatura
Sorghum/microbiologia
Sorghum/toxicidade
Tipo de Publ: Estudo de Avaliação
Estudo de Validação
Estudo Observacional
Responsável: AR635.1 - FCVyS - Servicio de Información y Documentación


  3 / 101 LILACS  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
Id: biblio-1116352
Autor: Duo Filho, Valter Batista; Siqueira, João Paulo Zen; Colombo, Tatiana Elias.
Título: Monitoramento de fungos anemófilos no ambiente de uma biblioteca no Município de São José do Rio Preto - Sp, Brasil / Anemophilic fungi monitoring in a library environment in the city of São Jose do Rio Preto, Brazil
Fonte: Arq. ciências saúde UNIPAR;24(2):75-80, maio-ago. 2020.
Idioma: pt.
Resumo: Os fungos desempenham vários papéis que impactam a humanidade de diversas maneiras. Suas características metabólicas são importantes na biotecnologia, porém, tais microrganismos podem desencadear alguns problemas de saúde pública e até mesmo serem letais. Objetivo: detectar a presença de fungos no acervo de uma biblioteca no município de São José do Rio Preto. Metodologia: foram coletadas quarenta amostras nas superfícies inanimadas (livros, estantes, documentos, mapas, artigos e revistas) das principais salas da biblioteca com o auxílio de swabs umedecidos em solução salina estéril, posteriormente encaminhados ao laboratório de Biomedicina da Universidade Paulista ­ UNIP. As amostras foram semeadas em meio de cultura ágar Sabouraud Dextrose (SDA), tendo adicionado cloranfenicol e incubadas a 30 °C. Foi realizada a colônia gigante em todas as cepas crescidas em SDA para a realização da técnica de microcultivo para a identificação dos fungos, de acordo com o Manual de Detecção e Identificação dos Fungos de Importância Médica da Agência Nacional de Vigilância Sanitária. Resultados: Houve positividade em trinta e uma amostras (78%) e em quatro delas foi observado mais de um tipo de colônia (13%). Das vinte e duas superfícies de livros analisadas, foram isolados e identificados: Aspergillus flavus, Aspergillus niger, Cunninghamella sp., Cladosporium sp., Curvularia sp., Mucor sp. e Nigrospora sp. Nas oito superfícies de estantes: Aspergillus flavus, Aspergillus niger, Aspergillus versicolor, Penicillium sp. e Scopulariopsis sp. e, nos dez documentos: Aspergillus nidulans, Aspergillus sp., Cladosporium sp., Cunninghamella sp. e Trichoderma sp. Conclusão: Os fungos encontrados estão amplamente distribuídos no ambiente como solo e ar e, por diversos fatores, instalam-se em locais como bibliotecas. Em condições favoráveis, podem infectar o homem e causar perdas patrimoniais para os acervos.

Fungi play many roles that impact humankind in different ways. Their metabolic characteristics are important in biotechnology; however, these microorganisms can trigger some public health problems or may even be lethal. Objective: detect the presence of fungi in the collection of a public library in the city of São José do Rio Preto, Brazil. Methods: a total of forty samples were collected from inanimate surfaces (books, shelves, documents, maps, articles and magazines) located in the main rooms of the library with swabs soaked in sterile saline solution and sent to the Universidade Paulista ­ UNIP laboratories. The samples were plated in Sabouraud Dextrose Agar (SDA) supplemented with chloramphenicol and incubated at 30 °C. The colonies that grew in SDA were isolated in Potato Dextrose Agar for performing the slide culture technique for the identification of the fungi, performed according to the Manual of Detection and Identification of Fungi of Medical Importance from the Brazilian Health Surveillance Agency (ANVISA). Results: Thirty-one samples (78%) were positive, and in four of them more than one fungus genus was observed (13%). From the twenty-two book surfaces analyzed, the following fungi were isolated and identified: Aspergillus flavus, Aspergillus niger, Cunninghamella sp., Cladosporium sp., Curvularia sp., Mucor sp. and Nigrospora sp. On the eight shelves: Aspergillus flavus, Aspergillus niger, Aspergillus versicolor, Penicillium sp. and Scopulariopsis sp. The ten documents analyzed presented the following fungi: Aspergillus nidulans, Aspergillus sp., Cladosporium sp., Cunninghamella sp. and Trichoderma sp.. Conclusion: These fungi are widely distributed in the environment such as in the soil and air, and due to several factors, they colonize public places, such as libraries. In favorable conditions, they may infect humans and cause diseases.
Descritores: Monitoramento Ambiental
Acervo de Biblioteca
Fungos
-Penicillium
Aspergillus flavus
Aspergillus nidulans
Aspergillus niger
Trichoderma
Biotecnologia
Cladosporium
Cunninghamella
Ágar
Infecções
Responsável: BR513.1 - Biblioteca Central


  4 / 101 LILACS  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo SciELO Chile
Texto completo
Id: biblio-950731
Autor: Mahilrajan, Subajini; Nandakumar, Jeyarani; Kailayalingam, Robika; Manoharan, Nilushiny Aloysius; SriVijeindran, SriThayalan.
Título: Screening the antifungal activity of essential oils against decay fungi from palmyrah leaf handicrafts
Fonte: Biol. Res;47:1-5, 2014. ilus, graf, tab.
Idioma: en.
Resumo: BACKGROUND: The whitish tender leaves of Palmyrah are used for making handicrafts. The problem with these articles is discolouration with time and become more brittle due to fungal attack. This could be prevented by some protective coating. Instead of expensive and harmful chemicals we decided to test natural plant essential oils to control fungal attack. Palmyrah leaf article decay fungi were isolated from two different sites of Jaffna peninsula. In this investigation Antifungal Activity of different plant essential oils from neem (Azadirachta indica), castor (Ricinus communis), citronella (Cymbopogon sp) and camphor (Cinnamomum camphora) obtained from local market have been evaluated against isolated fungi. For screening of Antifungal activity, tests and controls were set to determine minimum inhibitory concentration (MIC) and Percentage of Growth Inhibition. RESULTS: Morphologically three different types of Palmyrah leaf decay fungi were isolated and characterized asAspergillus niger, Aspergillus flavus and Penicillium sp. Neem and castor oils have recorded no significant (0.05 > P) antifungal activity while citronella and camphor oils showed significantly different antifungal activity compared with control. Camphor oil and Citronella oil showed 100, 58.13% of average growth inhibition for A. niger. 96.38, 51.32% for A.flavus and 84.99, 72.76% forPenicillium sp respectively. Camphor oil showed highest percentage of growth inhibition at lowest minimum inhibitory concentration compared with citronella oil. Camphor oil was found to be highly antifungal and most effective against A niger, and A. flavus, compared with Penicillium sp and gave 100 percentage of growth inhibitions at 5, 1 and 15 ml/dl minimum inhibitory concentration respectively. CONCLUSION: Significantly higher broad-spectrum of antifungal activity was observed in camphor oil than other tested oils because it showed highest percentage of growth inhibition at lowest inhibitory concentration. Therefore it could be used for the development of new environmental friendly antifungal agent for the preservation of leafy handicrafts. Further formulation, field experiments are necessary to achieve this target.
Descritores: Penicillium/efeitos dos fármacos
Aspergillus/efeitos dos fármacos
Óleos Vegetais/farmacologia
Óleos Voláteis/farmacologia
Arecaceae/microbiologia
Inibidores do Crescimento/farmacologia
Antifúngicos/farmacologia
-Penicillium/isolamento & purificação
Penicillium/crescimento & desenvolvimento
Aspergillus/isolamento & purificação
Aspergillus/crescimento & desenvolvimento
Aspergillus flavus/isolamento & purificação
Aspergillus flavus/crescimento & desenvolvimento
Aspergillus flavus/efeitos dos fármacos
Aspergillus niger/isolamento & purificação
Aspergillus niger/crescimento & desenvolvimento
Aspergillus niger/efeitos dos fármacos
Ricinus/química
Testes de Sensibilidade Microbiana/métodos
Cinnamomum camphora/química
Azadirachta/química
Cymbopogon/química
Tipo de Publ: Research Support, Non-U.S. Gov't
Responsável: CL1.1 - Biblioteca Central


  5 / 101 LILACS  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
Id: biblio-1052045
Autor: Zhao, Xiaobo; Li, Chunjuan; Yan, Caixia; Wang, Juan; Yuan, Cuiling; Zhang, Hao; Shan, Shihua.
Título: Transcriptome and proteome analyses of resistant preharvest peanut seed coat in response to Aspergillus flavus infection
Fonte: Electron. j. biotechnol;39:82-90, may. 2019. graf, ilus.
Idioma: en.
Projeto: Taishan Scholar Project of Shandong Province, China; . Agro-industry Technology Research System of Shandong Province, China; . Fine Breeding Project of Shandong Province, China; . Agricultural Scientific and Technological Innovation Project of Shandong Academy of Agricultural Sciences, China.
Resumo: BACKGROUND: The infection of peanut (Arachis hypogaea L.) seed coat by the pathogenic fungus Aspergillus flavus has highly negative economic and health impacts. However, the molecular mechanism underlying such defense response remains poorly understood. This study aims to address this issue by profiling the transcriptomic and proteomic changes that occur during the infection of the resistant peanut cultivar J11 by A. flavus. RESULTS: Transcriptomic study led to the detection of 13,539 genes, among which 663 exhibited differential expression. Further functional analysis found the differentially expressed genes to encode a wide range of pathogenesis- and/or defense-related proteins such as transcription factors, pathogenesis-related proteins, and chitinases. Changes in the expression patterns of these genes might contribute to peanut resistance to A. flavus. On the other hand, the proteomic profiling showed that 314 of the 1382 detected protein candidates were aberrantly expressed as a result of A. flavus invasion. However, the correlation between the transcriptomic and proteomic data was poor. We further demonstrated by in vitro fungistasis tests that hevamine-A, which was enriched at both transcript and protein levels, could directly inhibit the growth of A. flavus. Conclusions: The results demonstrate the power of complementary transcriptomic and proteomic analyses in the study of pathogen defense and resistance in plants and the chitinase could play an important role in the defense response of peanut to A. flavus. The current study also constitutes the first step toward building an integrated omics data platform for the development of Aspergillus-resistant peanut cultivars
Descritores: Arachis/genética
Proteoma/análise
Transcriptoma
-Arachis/microbiologia
Aspergillus flavus/fisiologia
Sementes/genética
Expressão Gênica
Quitinases
Aflatoxinas
Resistência à Doença/genética
Reação em Cadeia da Polimerase em Tempo Real
RNA-Seq
Responsável: CL1.1 - Biblioteca Central


  6 / 101 LILACS  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo SciELO Brasil
ALVES, Sydney Hartz
Texto completo
Id: biblio-951621
Autor: Denardi, Laura Bedin; Hoch Dalla-Lana, Bianca; Pantella Kunz de Jesus, Francielli; Bittencourt Severo, Cecília; Santurio, Janio Morais; Zanette, Régis Adriel; Alves, Sydney Hartz.
Título: In vitro antifungal susceptibility of clinical and environmental isolates of Aspergillus fumigatus and Aspergillus flavus in Brazil
Fonte: Braz. j. infect. dis;22(1):30-36, Jan.-feb. 2018. tab, graf.
Idioma: en.
Projeto: FAPERGS; . CNPq.
Resumo: ABSTRACT The in vitro susceptibility of 105 clinical and environmental strains of Aspergillus fumigatus and Aspergillus flavus to antifungal drugs, such as amphotericin B, azoles, and echinocandins was evaluated by the broth microdilution method proposed by the European Committee on Antimicrobial Susceptibility Testing (EUCAST). Following the EUCAST-proposed breakpoints, 20% and 25% of the clinical and environmental isolates of A. fumigatus, respectively, were found to be resistant to itraconazole (Minimal Inhibitory Concentration, MIC > 2.0 mg/L). Voriconazole showed good activity against A. fumigatus and A. flavus strains, except for one clinical strain of A. fumigatus whose MIC was 4.0 mg/L. Posaconazole (≤0.25 mg/L) also showed appreciable activity against both species of Aspergillus, except for six A. fumigatus strains with relatively higher MICs (0.5 mg/L). The MICs for Amphotericin B ranged from 0.06 to 1.0 mg/L for A. fumigatus, but were much higher (0.5-8.0 mg/L) for A. flavus. Among the echinocandins, caspofungin showed a geometric mean of 0.078 and 0.113 against the clinical and environmental strains of A. flavus, respectively, but had elevated minimal effective concentrations (MECs) for seven of the A. fumigatus strains. Anidulafungin and micafungin exhibited considerable activity against both A. fumigatus and A. flavus isolates, except for one environmental isolate of A. fumigatus that showed an MEC of 1 mg/L to micafungin. Our study proposes that a detailed investigation of the antifungal susceptibility of the genus Aspergillus from different regions of Brazil is necessary for establishing a response profile against the different classes of antifungal agents used in the treatment of aspergillosis.
Descritores: Aspergillus flavus/efeitos dos fármacos
Aspergillus fumigatus/efeitos dos fármacos
Antifúngicos/farmacologia
-Aspergillus flavus/isolamento & purificação
Aspergillus fumigatus/isolamento & purificação
Valores de Referência
Brasil
Testes de Sensibilidade Microbiana
Reação em Cadeia da Polimerase
Farmacorresistência Fúngica Múltipla
Limites: Humanos
Responsável: BR1.1 - BIREME


  7 / 101 LILACS  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
Id: biblio-1013372
Autor: Castellari, Claudia C; Marcos Valle, Facundo J; Pacin, Ana M.
Título: Observación de interacciones entre hifas de Fusarium verticillioides, Aspergillus flavus y Talaromyces funiculosus en microcultivos desarrollados en ambientes herméticos / Observation of interactions between hyphae of Fusarium verticillioides, Aspergillus flavus and Talaromyces funiculosus in microcultures developed in hermetic environments
Fonte: Rev. argent. microbiol;51(2):335-336, jun. 2019.
Idioma: es.
Descritores: Aspergillus flavus/isolamento & purificação
Aspergillus flavus/crescimento & desenvolvimento
Talaromyces/isolamento & purificação
Talaromyces/crescimento & desenvolvimento
Fusarium/isolamento & purificação
Fusarium/crescimento & desenvolvimento
-Meios de Cultivo Condicionados
Micobioma/fisiologia
Tipo de Publ: Ensaio Clínico
Responsável: AR635.1 - FCVyS - Servicio de Información y Documentación


  8 / 101 LILACS  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
Id: biblio-1003275
Autor: Barberis, Carla L; Carranz, Cecilia S; Magnoli, Karen; Benito, Nicolás; Magnoli, Carina E.
Título: Desarrollo y capacidad de remoción de los pesticidas atrazina, clorpirifós y endosulfán por parte de cepas de Aspergillus sección Flavi no toxigénicas / Development and removal ability of non-toxigenic Aspergillus section Flavi in presence of atrazine, chlorpyrifos and endosulfan
Fonte: Rev. argent. microbiol;51(1):3-11, mar. 2019. ilus, graf, tab.
Idioma: en.
Resumo: This study evaluated the in vitro effect of three concentrations of atrazine, chlorpyrifos and endosulfan on the growth parameters of four non-toxigenic Aspergillus section Flavi strains. The ability of the strains to remove these pesticides in a synthetic medium was also determined. Growth parameters were measured on soil extract solid medium supplied with 5,10 and 20mg/l of each pesticide, and conditioned to -0.70, -2.78, -7.06 and -10.0 water potential (MPa). Removal assays were performed in Czapek Doc medium (CZD) supplied with 20mg/l of each pesticide under optimal environmental conditions (-2.78 of MPa and 25 °C). The residual levels of each pesticide were detected by the reversed-phase HPLC/fluorescence detection system. The lag phases of the strains significantly decreased in the presence of the pesticides with respect to the control media. This result indicates a fast adaptation to the conditions assayed. Similarly, the mycelial growth rates in the different treatments increased depending on pesticide concentrations. Aspergillus oryzae AM 1 and AM 2 strains showed high percentages of atrazine degradation (above 90%), followed by endosulfan (56 and 76%) and chlorpyrifos (50 and 73%) after 30 days of incubation. A significant (p <0.001) correlation (r = 0.974) between removal percentages and growth rate was found. This study shows that non-toxigenic Aspergillus section Flavi strains from agricultural soils are able to effectively grow in the presence of high concentrations of atrazine, chlorpyrifos and endosulfan under a wide range of MPa conditions. Moreover, these strains have the ability to remove high levels of these pesticides in vitro in a short time.

En este estudio se evaluó los efectos in vitro de 3 concentraciones de atrazina, clorpirifós y endosulfán sobre los parámetros de crecimiento de 4 cepas no toxigénicas de Aspergillus sección Flavi. También se evaluó la capacidad de las cepas de remover los pesticidas. Los parámetros de crecimiento se ensayaron en medio agar extracto de suelo suplementado con 5, 10 y 20mg/l de cada pesticida y acondicionado a -0.70, -2.78, -7.06 y -10.0 de potencial de agua (MPa). Los ensayos de remoción se realizaron en medio Czapek Dox con 20mg/l de cada pesticida bajo condiciones óptimas de crecimiento (-2.78 de MPa y 25 °C). Los niveles residuales de atrazina, clorpirifós y endosulfán se detectaron en un sistema HPLC con detección por fluorescencia. La fase de latencia de las cepas disminuyó significantemente en presencia de los pesticidas, indicando una rápida adaptación a dichas condiciones. La velocidad de crecimiento se incrementó considerablemente dependiendo de la concentración de pesticida. Las cepas Aspergillus oryzae AM1 y AM2 mostraron porcentajes elevados de degradación de atrazina (aproximadamente el 90%), seguidos por endosulfán (56 y 76%) y clorpirifós (50 y 73%). Se observó una correlación (r = 0.974) significante (p <0.001) entre el porcentaje de pesticida removido y la velocidad de crecimiento. Este estudio muestra que cepas no-toxigénicas de Aspergillus sección Flavi aisladas de suelos agrícolas desarrollan eficientemente en presencia de altas concentraciones de atrazina, clorpirifós y endosulfán en un amplio rango de MPa. Además, presentan capacidad de remover in vitro altos niveles de pesticidas en corto tiempo.
Descritores: Praguicidas/antagonistas & inibidores
Aspergillus flavus/patogenicidade
Aspergillus oryzae/patogenicidade
-Aspergillus flavus/isolamento & purificação
Aspergillus oryzae/isolamento & purificação
Técnicas In Vitro
Parâmetros de Referência
Tipo de Publ: Ensaio Clínico
Estudo de Avaliação
Responsável: AR635.1 - FCVyS - Servicio de Información y Documentación


  9 / 101 LILACS  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
Id: biblio-1057392
Autor: Guan, Xuanli; Zhao, Yueju; Liu, Xiao; Shang, Bo; Xing, Fuguo; Zhou, Lu; Wang, Yan; Zhang, Chushu; Bhatnagar, Deepak; Liu, Yang.
Título: El factor de transcripción bZIP Afap1 afecta al estrés oxidativo y la biosíntesis de aflatoxinas en Aspergillus flavus / The bZIP transcription factor Afap1 mediates the oxidative stress response and aflatoxin biosynthesis in Aspergillus flavus
Fonte: Rev. argent. microbiol;51(4):292-301, dic. 2019. graf.
Idioma: en.
Resumo: Abstract Aflatoxin is a carcinogenic secondary metabolite produced mainly by Aspergillus flavus and Aspergillus parasiticus, which can seriously endanger the health of humans and animals. Oxidative stress is a common defense response, and it is known that reactive oxygen species (ROS) can induce the synthesis of a series of secondary metabolites, including aflatoxin. By using mutants lacking the afap 1 gene, the role of afap 1 gene in oxidative stress and aflatoxin synthesis was assessed. The growth of the mutant strains was significantly inhibited by the increase in the concentration of H2O2, inhibition was complete at 40mmol/l. However, in the quantitative analysis by HPLC, the concentration of AFB1 increased with the increased H 2O 2 until 10mmol/l. Following an analysis based on the information provided by the NCBI BLAST analysis, it was assumed that Afap1, a basic leucine zipper (bZIP) transcription factor, was associated with the oxidative stress in this fungus. Treatment with 5mmol/l H 2O 2 completely inhibited the growth of the mutant strains in afap 1 but did not affect the growth of the CA14PTs strain (non-mutant strain). In addition, the concentration of AFB 1 in the mutant strains was approximately V of that observed in the CA14PTs strain. These results suggested that Afap1 plays a key role in the regulation of oxidative stress and aflatoxin production in A. flavus. ©2018 Published by Elsevier España, S.L.U. on behalf of Asociación Argentina de Microbiología. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/ licenses/by-nc-nd/4.0/).

Resumen La aflatoxina es un metabolito secundario cancerígeno producido principalmente por Aspergillus flavus y Aspergillus parasiticus, que pone en riesgo grave a la salud de los humanos y los animales. El estrés oxidativo es una respuesta de defensa común, y es sabido que las especies reactivas de oxígeno (ROS) pueden inducir la síntesis de una serie de metabolitos secundarios, incluida la aflatoxina. Empleando mutantes carentes del gen afap1 se evaluó el papel de Afap1 en el estrés oxidativo y la síntesis de aflatoxinas. El crecimiento de las cepas mutadas se vio significativamente inhibido con el aumento de la concentración de H 2O 2, la inhibición fue completa a 40mmol/l. Sin embargo, en el análisis cuantitativo por HPLC, la concentración de la aflatoxina AFBi aumentó con el aumento de la concentración de H 2O 2 hasta 10mmol/l. Tras un análisis apoyado en la información provista por la herramienta NCBI BLAST, se supuso que Afap1, un factor de transcripción de la cremallera de leucina básica (bZIP), estaba asociado con el estrés oxidativo en este hongo. El tratamiento con 5mmol/l de H 2O 2 inhibió completamente el crecimiento de las cepas mutantes en afap1, pero no afectó el crecimiento de la cepa CA14PTs (cepa no mutada). Además, la concentración de AFB 1 en las cepas mutadas fue de aproximadamente 1/4 de la observada en CA14PTs. Estos resultados sugieren que Afap1 juega un papel clave en la regulación del estrés oxidativo y la producción de aflatoxinas en A. flavus.
Descritores: Aspergillus flavus/patogenicidade
Aflatoxinas/biossíntese
-Fatores de Transcrição/análise
Estresse Oxidativo/fisiologia
Tipo de Publ: Estudo de Avaliação
Responsável: AR635.1 - FCVyS - Servicio de Información y Documentación


  10 / 101 LILACS  
              first record previous record
seleciona
para imprimir
Fotocópia
Texto completo SciELO Brasil
Texto completo
Id: lil-546977
Autor: Pimentel, Flávio Araújo; Cardoso, Maria das Graças; Batista, Luis Roberto; Guimarães, Luiz Gustavo de Lima; Silva, Daiani Maria.
Título: Ação fungitóxica do óleo essencial de Tanaecium nocturnum (Barb. Rodr.) Bur. e K. Shum sobre o Aspergillus flavus isolado da castanha-do-Brasil (Bertholletia excelsa) / Fungitoxic action of the essential oil of Tanaecium nocturnum (Barb. Rodr.) Bur. and K. Shum on Aspergillus flavus isolated from the Brazil nut (Bertholletia excelsa)
Fonte: Acta amaz;40(1):213-220, mar. 2010. ilus, tab.
Idioma: pt.
Resumo: Neste trabalho, avaliou-se a capacidade fungitóxica do óleo essencial de folhas frescas de Tanaecium nocturnum sobre o Aspergillus flavus isolado da castanha-do-brasil, por meio das técnicas de contato e fumigação. Pelos resultados dos bioensaios realizados até 10 dias de incubação, verificou-se que a inibição total do crescimento micelial ocorreu quando se utilizou o óleo essencial nas concentrações de 782 ppm (técnica de contato) e 1000 ppm (técnica de fumigação). Em ambas as técnicas, o óleo essencial inibiu a esporulação a partir da concentração de 500 ppm. Observou-se que nos cinco primeiros dias de incubação não houve diferença significativa nos resultados apresentados pelas duas técnicas estudadas, havendo a partir daí uma redução da atividade do óleo essencial nas concentrações inferiores a 1000 ppm pelo teste de fumigação. A ação fungitóxica do óleo essencial sobre o microrganismo estudado pode ser atribuída à presença do benzaldeído (composto majoritário do óleo essencial estudado), em associação com outros compostos também presentes nesse óleo essencial, tais como; álcool benzílico, benzoato de benzila e mandelonitrila.

The present work sought to evaluate the fungitoxic activity of the essential oil from fresh Tanaecium nocturnum fresh leaves on Aspergillus flavus isolated from Brazil nuts, using contact and fumigation techniques. The results of bioassays performed up to 10 days of incubation demonstrated that total inhibition of mycelial growth occurred when using the essential oil at concentrations of 782 ppm (contact technique) and 1000 ppm (fumigation technique). In both techniques, the essential oil inhibited the formation of spores at the concentration of 500 ppm. No significant difference in the results presented by the two techniques was observed in the first five days of incubation. After this period, the essential oil showed a reduction in activity at concentrations lower than 1000 ppm in the fumigation test. The fungitoxic activity of the essential oil on the organism studied can be attributed to the presence of benzaldehyde (major component of the essential oil), in combination with other compounds also present in this oil, such as, benzyl alcohol, benzyl benzoate and mandelonitrila.
Descritores: Aspergillus flavus
Óleos Voláteis
Bertholletia
Fungos
Responsável: BR6.1 - BCS - Biblioteca de Ciências da Saúde



página 1 de 11 ir para página                         
   


Refinar a pesquisa
  Base de dados : Formulário avançado   

    Pesquisar no campo  
1  
2
3
 
           



Search engine: iAH v2.6 powered by WWWISIS

BIREME/OPAS/OMS - Centro Latino-Americano e do Caribe de Informação em Ciências da Saúde