Mycoflora of post-harvest maize and wheat grains and the implication of their contamination by molds.

Thirteen fungi including toxigenic Aspergillus nidulans and A. clavatus were isolated from the grains. The isolated fungi grew well at 25-30 degrees C. A. clavatus and A. nidulans were grown in liquid maize yeast extract medium and wheat yeast extract medium. Both fungi produced amylases on the two media and on the basal medium at 30 degrees C. During incubation more total reducing sugars were detected in maize grains than in wheat while non-reducing sugars were detected than reducing sugars in both grains. A. clavatus showed highest amylase activities at 25-30 degrees C and at a pH 7-8 while 30 degrees C and pH 6.0 were the optimum conditions for highest amylase activities of A. nidulans. During incubation with both fungi a decrease in the protein and carbohydrate contents of both grains was recorded while more fat was accumulated in the grains.