Characterization of Aspergillus flavus isolated from winemaking grapes

Concern about filamentous fungi in vineyards has been traditionally linked to the spoilage of grapes. However, the recent detection of ochratoxin A in wines has increased the interest in mycotoxins. Although not very common in grapes, Aspergillus flavus is occasionally isolated from grapes. A. flavus is the main producer of the well known carcinogenic mycotoxins, the aflatoxins, and the presence of this fungus and aflatoxins is of major food safety concern. The identification of A. flavus is not straightforward due mainly to similarities with its closely related species (A. parasiticus, A. nomius). Various morphological and biochemical parameters may be used for identification: Color of colonies on Czapek Medium (CZ), seriation of conidial heads, conidia ornamentation, production of aflatoxins B1, B2, G1 and G2, and production of cyclopiazonic acid.FC