Aflatoxin, cyclopiazonic acid and β-nitropropionic acid production by Aspergillus section Flavi from dried figs grown in Turkey

Abstract

Aspergillus section Flavi isolates from dried figs were screened for aflatoxins, cyclopiazonic acid (CPA) and β-nitropropionic acid (BNP) production on yeast extract sucrose, czapek yeast extract and potato dextrose agar media. According to molecular identification, Aspergillus flavus (n=51) was dominant followed by Aspergillus parasiticus (n=5) and Aspergillus tamarii (n=1). All isolates were toxigenic producing at least one of the mycotoxins. 98% of the A. flavus strains produced aflatoxins (0.3-1,620 ng/g) and CPA (0.07-398.2 μg/g), with 31% of them also producing BNP (7.9-1,571.2 ng/g). All isolates of A. parasiticus were aflatoxins producers (106.4-1,255 ng/g), while 2 of them (40%) also produced CPA at a very low level (0.05-0.06 μg/g). Regarding toxigenic profiles of A. flavus and A. parasiticus, 6 and 3 chemotypes were classified, respectively. A. flavus isolates producing both B type of aflatoxins and CPA, comprised the most represented chemotype followed by the chemotype consisting of aflatoxin B1, CPA and BNP producers. Regarding A. parasiticus chemotypes, two can be considered atypical being producer of only the B type of aflatoxins and being producer of the B, G type of aflatoxins along with CPA. To the best of our knowledge, an A. flavus isolate producing CPA and BNP but not aflatoxin has been found for the first time.