| Abstract: | An antitumour-promoting activity in two-stage carcinogenesis, was found in the methanol and ethyl acetate extracts of the Japanese edible mushroom ‘Buna-shimeji’, Hypsizigus marmoreus (Tricholomataceae). From the active fractions of the extracts, two sterols, ergosterol and ergosterol 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 developing an effective method of cancer prevention. |
