Abstract: The methanol extract of chaga (sclerotia of Inonotus obliquus) inhibited the promoting effect of 12-O-tetradecanoylphorbol-13-acatate (TPA) applied twice weekly on skin tumor formation in mice initiated with 7,12-dimethylbenz [a] anthracene. The methanol extract from chaga led to the isolation of eight triterpenoids (1–8). The anti-inflammatory activity of the isolated lanostane-type triterpenes was evaluated against TPA-induced inflammatory ear edema in mice. These compounds showed markedly anti-inflammatory effects, with a 50% inhibitory dose of 125-458 nmol/ear.

Keywords: Chaga, Inonotus obliquus, lanostane-type triterpene, antitumor promotion, anti-inflammation, two-stage carcinogenesis.