AFLATOXIN B_1 PRODUCTION BY ASPERGILLUS SECTION NI-GRI STRAINS ISOLATED FROM GREEK DRIED VINE FRUITS AND COMPETITION WITH ASPERGILLUS PARASITICUS

摘要

Aflatoxin B_1 (AFB_1) represents one of the most important food toxicants. The most important aflatoxin producers are Aspergillus flavus and A. parasiticus. Strains identified as Aspergillus section Nigri were isolated from dried vine fruits originating from Corinthos (1 strain) and Crete (3 strains). In this study, the effect of Aspergillus section Nigri strains on growth and AFB_1 production by A. parasiticus was investigated during 18 days of incubation in liquid Yeast Extract Sucrose medium. It was found, that Aspergillus section Nigri strains produced AFB_1, even at low levels. On the 12th day of incubation, which was the day of AFB_1 maximum production for the four strains, the AFB_1 levels were 98.3 - 99.9 % less than those recorded for Aspergillus parasiticus, on the same day. The AFB_1 production by the strain of A. parasiticus on the 12th day of incubation was reduced by 97.5 % when co-cultured with the strain of Aspergillus section Nigri from Corinthian dried vine fruit, whereas it was reduced by 99.9 % when co-cultured with the three strains from Cretan dried vine fruits. These findings indicate that the presence of Aspergillus section Nigri strains may inhibit almost completely the AFB_1 production by A. parasiticus.