INHIBITORY EFFECTS OF ERGOSTEROL ISOLATED FROM THE EDIBLE MUSHROOM HYPSIZIGUS-MARMOREUS ON TPA-INDUCED INFLAMMATORY EAR EDEMA AND TUMOR PROMOTION IN MICE

An antitumour-promoting activity in two-stage carcinogenesis, was foun d in the methanol and ethyl acetate extracts of the Japanese edible mu shroom 'Buna-shimeji', Hypsizigus marmoreus (Tricholomataceae). From t he active fractions of the extracts, two sterols, ergosterol and ergos terol peroxide, were isolated. The isolates showed inhibitory activity against 12-O-tetradecanoylphorbol-13-acetate induced ear inflammation in mice, and ergosterol markedly inhibited tumour promotion in a two- stage carcinogenesis experiment. These sterols may be useful in develo ping an effective method of cancer prevention.