Chemical constituents from the stems of garcinia cylindrocarpa and the stem bark of garcinia picrorhiza and garcinia tetrandra

Abstract

Aiming to discover novel bioactive secondary metabolites from genus Garcinia, we performed phytochemical and biological investigations of three Garcinia species collected from Indonesia. A series of chromatographic techniques and spectroscopic data analysis were used to isolate and characterize the Garcinia phytochemicals. The cytotoxicity of the isolated compounds was evaluated against five human cancer cell lines (HeLa S3, Hep G2, HT-29, MCF-7, and KB) using MTT assay. Four new xanthones, cylindroxanthones D–G, and two new biphenyls, cylindrobiphenyls A and B, together with 28 known compounds were successfully isolated from G. cylindrocarpa stems. From the stem bark of G. tetrandra, nine new xanthones, tetrandraxanthones A–I, were identified along with 22 previously described analogues. Eight new polyprenylated benzoylphloroglucinols (PPBPs), picrorhizones A–H, and four known analogues were reported from the stem bark of G. picrorhiza. Among the tested compounds, 9-hydroxycalabaxanthone showed significant cytotoxicity against five human cancer cell lines with IC50 values in the range of 1.6–3.4 µM, while 2-deprenylrheediaxanthone B and picrorhizone F were active against four cancer cells, except HT-29, with IC50 values ranging from 2.2 to 9.4 µM.