INHIBITORY EFFECTS OF PERSIMMON (DIOSPYROS-KAKI) EXTRACT AND RELATED POLYPHENOL COMPOUNDS ON GROWTH OF HUMAN LYMPHOID LEUKEMIA-CELLS

We have investigated the effects of persimmon (Diospyros kaki) extract (PS) and related polyphenol compounds such as catechin (C), epicatech in (EC), epicatechingallate (EGG), epigallocatechin (EGG), and epigall ocatechingallate (EGCG) on the growth of human lymphoid leukemia Molt 4B cells, We found that PS, EGG, EGG, and EGCG strongly inhibited the growth of the cells in a dose-dependent manner, while C and EC inhibit ed the growth of the cells only moderately, Ornithine decarboxylase (O DC), a rate-limiting enzyme of polyamine biosynthesis, was inhibited b y 10-20% by these polyphenol compounds, The morphology of the Molt 4B cells indicated severe damage 3 days after treatment with PS, EGG, EGG , and EGCG, Irregular shape of the cells and DNA fragmentation were ob served in PS, EGG, EGG, or EGCG-treated cells, These results suggest t hat PS, EGG, EGG, and EGCG induce apoptosis (programmed cell death) of Molt 4B cells.