Abstract:
Phytochemical investigation on the dichloromethane stem bark extract of Calophyllum castaneum resulted in
the isolation of five compounds, namely isoblancoic acid (1), blancoic acid (2), euxanthone (3), friedelin (4) and
friedelinol (5). All these compounds were isolated for the first time from this plant. Their chemical structures were
elucidated based on the spectroscopic analyses. The cytotoxicity of compounds 1-5 was assessed on a panel of cancer
cell lines including bone (Saos-2, mg63), colorectal (HT29, Caco-2, HCC2998, SW48, HCT116, KM12), liver (HepG2),
lung (H1299, Calu-3), and brain (C6), using 5-fluorouracil as positive control. Pronounced antiproliferative activities
were observed for compound 1 which exhibited a comparable activity with the positive control, against brain (C6) and
colorectal (SW48, KM12, HCT116) cancer cell lines showing IC50 values in the range of 14 to 65µM. Meanwhile,
compound 5 displayed a greater cytotoxic effect showing at least 2-fold more strongly than the positive control, against
C6 brain cancer cells. The assay findings have unveiled the therapeutic value of phytochemicals from Calophyllum
castaneum as anti-cancer agents
