CARTHAMI FLOS EXTRACT AND ITS COMPONENT, STIGMASTEROL, INHIBIT TUMOR PROMOTION IN MOUSE SKIN 2-STAGE CARCINOGENESIS

An antitumour-promoting activity in two-stage carcinogenesis, is found in the methanol extract of the Carthami Flos (Carthamus tinctorius L.; Compositae), which is a traditional Chinese medicine and natural pigment of rouge additivies in certain Asian countries. From these active fractions, Delta(5)- and Delta(7)-sterol fractions were separated. The separation was examined for inhibitory activity against TPA-induced inflammatory ear oedema in mice. Stigmasterol (71% in the mixture) was the most abundant of 14 sterols identified in the Delta(5)-sterol fraction. Schottenol (70% in the mixture) constituted the dominant sterol of the Delta(7)-sterol fraction. Furthermore, stigmasterol markedly inhibited tumour promotion in two-stage carcinogenesis experiments.