Immunomodulatory and anticancer activities of phenolics from Garcinia mangostana fruit pericarp

Abstract The methanolic extract of Garcinia mangostana fruit pericarp was partitioned into butanol and water fractions in this work. Three major phenolics were purified and identified as P 1 [1,3,6,7-tetrahydroxy-2,8-(3-methyl-2-butenyl) xanthone], P 2 [1,3,6-trihydroxy-7-methoxy-2,8-(3-methyl-2-butenyl) xanthone] and P 3 (epicatechin). Strong antioxidant activities were detected for P 1 –P 3 . In vitro cell proliferation trials indicated that P 1 and P 3 exhibited good immunomodulatory activities when 7.5 μg/ml was used. Furthermore, P 1 and P 3 showed good cytotoxicities against human breast cancer cells (MCF-7) and human colon cancer cells (LOVO). P 1 exhibited the maximal cytotoxicity of 73.06% against MCF-7 cells and of 46.27% against LOVO cells when 62.5 μg/ml was used. The cytotoxicities of P 1 , P 2 , P 3 and paclitaxel against normal embryonic lung fibroblast cells (HELF) were in a decreasing order: paclitaxel > P 3  > P 1  > P 2. These results suggested that P 1 and P 3 could be used as a potential anticancer agent.