OCHRATOXIN-A - AN ANTIINSECTAN METABOLITE FROM THE SCLEROTIA OF ASPERGILLUS-CARBONARIUS NRRL-369

Ochratoxin A, a known mycotoxin with demonstrated toxicity to insects, has been isolated from the sclerotia of the fungus Aspergillus carbon arius NRRL 369. The sclerotia, harvested from a solid substrate fermen tation of corn kernels at 28 degrees C, produced quantities of ochrato xin A exceeding 50 ppm/g dry weight of sclerotia. Evidence is presente d that ochratoxin A accounts for the activity of the methanol extract against larvae of the detritivorous beetle Carpophilus hemipterus (Nit idulidae) (75% reduction in feeding rate) and corn ear worm Helicoverp a tea (50% mortality with 99% reduction in weight gain among surviving larvae) when incorporated into a pinto bean diet at levels less than those occurring naturally in the sclerotia.