Sambutoxin, a new mycotoxin produced by toxic Fusarium isolates obtained from rotted potato tubers, it can cause toxic effects in rats, including body weight loss, feed refusal, hemorrhage in the stomach and intestines, and, finally, death when rats were fed diets supplemented with 0.05 and 0.1% sambutoxin. Sambutoxin has in vitro cytotoxicity against various human and murine tumor cells and values of sambutoxin ranged from 46.2 to 1,425.6 ng/ml. It inhibits rabbit platelet aggregation, which may be party due to the decrease of ATP release.