Abstract

S. Melki Ben Fredj*, S. Chebil and A. Mliki

A survey was conducted to access mycotoxin-producing fungi and to evaluate the ochratoxin A (OTA) and the Aflatoxin B1 (AFB1) potential production for fungal strains contaminating table grapes in different Tunisian vineyards. Among 100 Aspergillus isolates, Aspergillus niger aggregate were the most frequent (70%) followed by Aspergillus carbonarius (7%) and Aspergillus flavus (23%). The mycotoxigenic capacity of the isolates was tested in culture media revealed that the highest levels of OTA production were obtained with strains of A. carbonarius (80% of them) whereas only 5% of A. niger aggregate were OTA producers. Furthermore, 39% of the A. flavus produced aflatoxin B1 (between 21 and 54 µg/g). Finally, we demonstrated, for the first time, that 3% of the Penicillium isolates (especially Penicillium expansum) were OTA producers in grapes.