Keywords
toxigenic fungi
aflatoxins
ochratoxin A
coconut agar medium
corn medium
How to Cite
Abstract
Screening tests for aflatoxins B1, B2, G1 and G2, ochratoxin A and sterigmatocystin production
were performed in 13 strains of Aspergillus spp, isolated from the terrestrial environment in the Brazilian
Atlantic Rainforest (São Paulo State/Brazil). Coconut agar medium and moistened corn were employed as
substrates. The fungal extracts obtained from both media were submitted to thin-layer chromatography and the toxins were estimated according to the intensity of their fluorescence observed under UV light. None of the tested strains presented any of the mentioned mycotoxins. Because many unknown fluorescent spots were present, it was necessary to proceed a confirmation step using multiple chromatography, two dimensional chromatography and derivatization. In view of the accuracy of the employed methods and the
presence of many unknown fluorescent spots, the need of further studies on the production of others mycotoxins of fungi isolated under tropical conditions is justified.
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