Novel dammarane-type sapogenins from Panax ginseng berry and their biological activities

Three new dammarane-type sapogenins (1, 3, and 5) together with two known ones (2 and 4) were isolated from the total hydrolyzed saponins extracted from Panax ginseng berry. Their structures were elucidated using a combination of 1D and 2D 1H and 13C NMR spectra and mass spectroscopy as 20(R)-25-methoxyl-dammarane-3β,12β,20-triol (1), 20(R)-25-methoxyl-dammarane-3β,6α,12β,20-tetrol (2), 20(R)-20-methoxyl-dammarane-3β,12β,25-triol (3), 20(R)-20,25-dimethoxyl-dammarane-3β,12β-diol (4), and (12R,20S,24S)-20,24-; 12,24-diepoxy-dammarane-3β-ol (5). Their antitumor activities were evaluated in six human cancer cell lines. The novel compounds 1 and 3 showed significant cytotoxic activity against the six cell lines. The IC50 values of 3 against HepG2, Colon205, and HL-60 were the lowest (8.78, 8.64, and 3.98 μM, respectively). Compounds 1 and 20(S)-25-OCH3-PPD, which are a pair of configuration isomers, showed a 10- to 100-fold greater growth inhibition than ginsenoside-Rg3 (an anti-cancer clinical agent in China). The data presented here may be useful for the development of novel anti-cancer agents.

Three new dammarane-type sapogenins (1, 3, and 5) together with two known ones (2 and 4) were isolated and identified from the total hydrolyzed saponins extracted from the fruits of Panax ginseng based on physicochemical characteristics and NMR data. Their antitumor activities were evaluated in six human cancer cell lines (MCF-7, HepG2, Du145, Colon205, A549, and HL-60). The novel compounds 1 and 3 showed significant cytotoxic activity against six cell lines and the IC50 values of 3 to HepG2, Colon205, A549, and HL-60 were much lower. These findings suggest a structure–activity relationship among dammarane-type sapogenins: the antitumor effects of compounds which have monomethoxyl group were more significant than those of compounds with no or two methoxyl groups.Figure optionsDownload as PowerPoint slide