| Abstract
| - Myrica rubra var. acuminata is a native shrub widely distributed and used as folk medicine in Taiwanfor stomach disorders and diarrhea. Column chromatography combined with cytotoxic bioassay-guided fractionation was performed to isolate the antitumor principles from fresh leaves of M. rubravar. acuminata. The 20% MeOH eluate fraction of M. rubra var. acuminata inhibited the viability ofHeLa and P-388 cells in an in vitro assay and an in vivo P-388 tumor-bearing CDF1 mouse model.The percent increase in life span (%ILS) of 20% MeOH eluate fraction was greater than 125%. (−)-Epigallocatechin 3-O-gallate (1) and prodelphinidin A-2,3‘-O-gallate (2) were isolated from D-20 asthe antitumor principle components. Both compounds can inhibit the growth of HeLa cells, but 1 hadlower cytotoxic effects in normal cervical fibroblasts than did 2. Moreover, pretreatment with acaspase-3 specific inhibitor prevented 1- and 2-induced poly(ADP-ribose) polymerase cleavage. Inview of these results, we suggest that 1 and 2 can induce apoptosis in HeLa cells and that activationof caspase-3 may provide a mechanistic explanation for their cytotoxic effects. Therefore, we suggestthat the 20% MeOH eluate fraction extract is good for health and that M. rubra var. acuminata is aneconomically valuable plant. Keywords: Myrica rubra var. acuminata; Myricaceae; apoptosis; HeLa cells; P-388 cells; (−)-epigallocatechin 3-O-gallate; prodelphinidin A-2,3‘-O-gallate
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