Mycotoxin-producing potential of fungi isolated from amaranth seeds in Argentina.

To evaluate the potential for mycotoxin production by molds in amaranth grains, the mycoflora was determined both before and after surface disinfection on dichloran-chloramphenicol-peptone agar (DCPA) and dichloran-18% glycerol agar (DG18). On both media Aspergillus, Penicillium, Fusarium and Alternaria were the predominant genera. A flaus and A. parasiticus were the Aspergillus species most frequently isolated. P. chrysogenum was the species most common among the penicillia. F. equiseti was the predominant Fusarium species. Isolates of Aspergillus, Penicillium and Fusarium were screened for mycotoxin production on sterile rice substrate and also using a simple screening method. Toxinogenic strains of A. flavus and A. parasiticus (aflatoxins), A. versicolor (sterigmatocystin), P. citrinum (citrinin), P. viridicatum (penicillic acid), F. moniliforme, F. equiseti and F. semitectum (zearalenone), were encountered. The simple screening method for toxinogenic molds showed good performance for the detection of molds producing aflatoxins and zearalenone compared with mycotoxins production on the natural substrate.