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Rezende,Elisângela de Fátima; Borges,Josiane Gonçalves; Cirillo,Marcelo Ângelo; Prado,Guilherme; Paiva,Leandro Carlos; Batista,Luís Roberto. |
The genera Aspergillus comprises species that produce mycotoxins such as aflatoxins, ochratoxins and patulin. These are cosmopolitan species, natural contaminants of agricultural products. In coffee grains, the most important Aspergillus species in terms of the risk of presenting mycotoxins belong to the genera Aspergillus Section Circumdati and Section Nigri. The purpose of this study was to assess the occurrence of isolated ochratoxigenic fungi of coffee grains from organic and conventional cultivation from the South of Minas Gerais, Brazil, as well as to evaluate which farming system presents higher contamination risk by ochratoxin A (OTA) produced by fungi. Thirty samples of coffee grains (Coffea arabica L.) were analysed, being 20 of them of... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Aspergillus ochraceus; Ochratoxin A; Arabica coffee. |
Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822013000200006 |
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Palacios-Cabrera,Héctor; Taniwaki,Marta Hiromi; Hashimoto,Jorge Minoru; Menezes,Hilary Castle de. |
The objective of this paper was to determine the influence of three culture media with different water activities, times of incubation and temperatures on the growth of A. ochraceus, A. carbonarius and A. niger. Spores of A. ochraceus, A. carbonarius and A. niger were inoculated onto three culture media: Czapeck Yeast extract Agar (CYA), Dichloran 18% Glycerol Agar (DG18) and Malt Yeast extract 40% Glucose Agar (MY40G). The plates were incubated at five different temperatures (8, 25, 30, 35 and 41ºC). The growth of fungi was evaluated every 24h, measuring the colony diameter (mm). None of the species grew at 8ºC in any culture media. For A. carbonarius, 30ºC was the best temperature for growth while for A. niger temperatures above 30ºC were better in all... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Aspergillus ochraceus; Aspergillus carbonarius; Aspergillus niger; Growth measurement; Water activity; Temperature. |
Ano: 2005 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822005000100005 |
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Almeida,Ana Paula Morais Martins; Dias,Eustáquio Souza; Pereira,Ricardo Tadeu Galvão; Toledo,Rômulo César Clemente; Pfenning,Ludwig Heinrich. |
A obtenção de protoplastos é uma ferramenta importante para a transformação genética de fungos. Neste trabalho foi estudada a influência de fatores como idade micelial, tipo e concentração de enzimas e estabilizadores osmóticos na produção de protoplastos de Aspergillus ochraceus. Os melhores resultados de produção de protoplastos foram obtidos utilizando-se NH4Cl 0,8mol L-1 como estabilizador osmótico, micélio com 24h de crescimento e a combinação de Lysing Enzymes e Meicelase ambas, a 20mg mL-1. Entretanto, bons resultados foram também obtidos com a utilização apenas de Lysing Enzymes. |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Aspergillus ochraceus; Protoplastos e estabilizador osmótico. |
Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782008000500043 |
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Gonçalves,Heloísa Bressan; Riul,Alana Jacomini; Quiapim,Andréa Carla; Jorge,João Atílio; Guimarães,Luis Henrique Souza. |
Background: Tannases are enzymes that may be used in different industrial sectors as, for example, food and pharmaceutical. They are obtained mainly from microorganisms, as filamentous fungi. However, the diversity of fungi stays poorly explored for tannase production. In this article, Aspergillus ochraceus is presented as a new source of tannase with interesting features for biotechnological applications. Results: Extracellular tannase production was induced when the fungus was cultured in Khanna medium with tannic acid as carbon source. The extracellular tannase was purified 9-fold with 2% recovery and a single band corresponding to 85 kDa was observed in SDS-PAGE. The native apparent molecular mass was estimated as 112 kDa. Optima of temperature and pH... |
Tipo: Journal article |
Palavras-chave: Aspergillus ochraceus; Gallic acid; Tannase; Tannic acid; Tannin acyl hydrolase. |
Ano: 2012 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000500004 |
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