The toxins were purified by organic extraction, thin layer chromotography, and visualized by Ultra Violet light. Aflatoxin is a mixture of closely related molecules. Aflatoxins B1 B2, G1, and G3. Aflatoxins are bisfuranocoumarins . Structures of aflatoxins are show in t he handout.
Aflatoxins are among the most highly carcinogenic materials known.
Individual kernels may have 300,000 to 600,000 ppb with adjacent non-infected kernels having 4,000 ppb. This is enough aflatoxin to be distributed among 30,000 kernels such that each kernel would be at the tolerance level. Chronic exposure to aflatoxin has lowered feed efficiency, depressed the immune system, and reduced reproductive efficiency. Aflatoxin alters ruminal function by decreasing cellulose digestion, vola tile fatty acid formation, proteolysis and motility. Corn is the grain most susceptible to aflatoxins contamination in the United States.