Interactions of saprophytic yeasts with a nor mutant of Aspergillus flavus.
The nor mutant of Aspergillus flavus has a defective norsolorinic acid reductase, and thus the aflatoxin biosynthetic pathway is blocked, resulting in the accumulation of norsolorinic acid, a bright red-orange pigment. We developed a visual agar plate assay to monitor yeast strains for their ability to inhibit aflatoxin production by visually scoring the accumulation of this pigment of the nor mutant. We identified yeast strains that reduced the red-orange pigment accumulation in the nor mutant. These yeasts also reduced aflatoxin accumulation by a toxigenic strain of A. flavus. These yeasts may be useful for reducing aflatoxin contamination of food commodities.
Hua
S S
SS
Western Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, Albany, California 94710, USA. ssth@pw.usda.gov
Baker
J L
JL
Flores-Espiritu
M
M
D000348:Aflatoxins / Q000037:antagonists & inhibitors / Q000096:biosynthesis*; D000429:Alcohol Oxidoreductases / Q000235:genetics* / Q000378:metabolism; D000880:Anthraquinones / Q000378:metabolism*; D001231:Aspergillus flavus / Q000201:enzymology / Q000235:genetics / Q000502:physiology*; D003470:Culture Media; D005656:Fungal Proteins; D009154:Mutation; D064430:NAD (+) and NADP (+) Dependent Alcohol Oxidoreductases; D014197:Trees / Q000382:microbiology; D015003:Yeasts / Q000302:isolation & purification / Q000502:physiology*
D000348:Aflatoxins; D000880:Anthraquinones; D003470:Culture Media; D005656:Fungal Proteins; D000429:Alcohol Oxidoreductases; D064430:NAD (+) and NADP (+) Dependent Alcohol Oxidoreductases; C062609:norsolorinic acid ketoreductase; C002754:norsolorinic acid