A total of 41 species and one variety related to 11 genera of filamentous fungi were isolated from 80
corn grain samples. The total fungal units emerged from non-surface disinfected (NSD) corn grains were much
higher than those emerged from surface disinfected (SD) corn grains. However, the number of isolated species in
case of SD corn grains exceeded those in case of NSD corn grains.
Aspergillus and Penicillium were the most
predominant genera.
Fusarium was recovered as the third most common genus of which F. verticillioide was the
most prevalent species. Thin layer chromatography (TLC) showed that of all corn samples tested only one was
contaminated by T-2 toxin while the other 79 samples were completely free of any detectable levels of
mycotoxins. Methanol extracts of
Fusarium isolates grown on corn medium showed that 59 out of the 90
Fusarium extracts contained at least one of the following Fusarium toxins: fumonisins B1 and B1 & B2,
zearalenone and deoxynivalenol. Most of
F. verticillioides isolates (44 out of 76) were fumonisins producers. The
HPLC analysis of crude extracts confirmed the results achieved by TLC plates. The highest yield of fumonisin B
(2015 µg/kg corn medium) was obtained from an isolate of Fusarium verticillioides.