Production of ochratoxins in different cereal products by Aspergillus ochraceus.
The effects of temperature and length of incubation on ochratoxin A production in various substrates were studied. The optimal temperature for toxin production by Aspergillus ochraceus NRRL-3174 was found to be around 28 C. Very low levels of ochratoxin A are produced in corn, rice, and wheat bran at 4 C. The optimal time for ochratoxin A production depends on the substrate, ranging from 7 to 14 days at 28 C. Ochratoxin B and dihydroisocoumaric acid, i.e., one of the hydrolysis products of ochratoxin A, were produced in rice but at levels considerably lower than ochratoxin A. No ochratoxin C was produced in rice at 28 C. When added to rice cereal or oatmeal, the toxin was found to be very stable over prolonged storage and even to autoclaving for 3 hr.
D001230:Aspergillus / Q000378:metabolism*; D002855:Chromatography, Thin Layer; D003374:Coumarins / Q000096:biosynthesis*; D002523:Edible Grain; D005506:Food Contamination; D005511:Food Handling; D005516:Food Microbiology; D009183:Mycotoxins / Q000096:biosynthesis*; D009793:Ochratoxins / Q000032:analysis / Q000096:biosynthesis; D012275:Oryza; D013242:Sterilization; D013696:Temperature; D013997:Time Factors; D014908:Triticum; D003313:Zea mays
D003374:Coumarins; D009183:Mycotoxins; D009793:Ochratoxins