생리활성에 따른 용매분획을 통해 으름(Akebia quinata) 과피로부터 4종의 사포닌을 분리하였다. 으름 과피를 에탄올로 추출한 후 디클로로메탄, 에틸아세테이트, 부탄올 및 물 층으로 순차분획하였으며 분광학적 분석을 통해 부탄올 분획으로부터3-O--L-arabinopyranosyl hederagenin (-hederin), 3-O--L-rhamnopyranosyl (12) -L-arabinopyranoly oleanolic acid (-h

Four saponins (1~4) were isolated from Akebia quinata pericarp through bioassay-guided fractionation. Pericarps of A. quinata were extracted with ethanol and sequentially fractionated with dichloromethane, ethyl acetate, butanol and water. Compounds 1~4 from the butanol fraction were identified as 3-O--L-arabinopyranosyl hederagenin (-hederin), 3-O--L-rhamnopyranosyl (12) -L-arabinopyranoly oleanolic acid (-hederin), 3-O--D-xylopyranosyl (13) -L-arabinopyranosyl hederagenin (saponin C), and 3-O -L-rhamnopyranosyl (12) -L-arabinopyranosyl hederagenin (-hederin) based on the spectroscopic evidences, respectively. Oleanolic acid and hederagenin were identified as the corresponding sapogenins by acid-hydrolysis. These compounds exhibited strong cytotoxic activity in MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxy-methoxyphenyl)-2-(4-sulfophenyl)-2H- tetrazolium, inner salt] assay on HepG2 cells. -Hederin obviously attenuated the expression of bcl-2, an anti-apoptotic protein. All of the compounds also induced the activity of caspase-3, an apoptotic enzyme, while -hederin was the most potent activator of the enzyme. Our data demonstrate for the first time the apoptosis-inducing activity of A. quinata. These results suggest that A. quinata could be used as a potential source of natural cancer chemopreventive agents.

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