Interactions of saprophytic yeasts with a nor mutant of Aspergillus flavus

The nor mutant of Aspergillus flavus has a defective norsolorinic acid redu ctase,and thus the aflatoxin biosynthetic pathway is blocked, resulting in the accumulation of norsolorinic acid, a bright red-orange pigment. We deve loped a visual agar plate assay to monitor yeast strains for their ability to inhibit aflatoxin production by visually scoring the accumulation of thi s pigment of the nor mutant. We Identified yeast strains that reduced the r ed-orange pigment accumulation in the nor mutant. These yeasts also reduced aflatoxin accumulation by a toxigenic strain of A. flavus. These yeasts. m ay be useful for reducing aflatoxin contamination of food commodities.