Cytotoxic Metabolites from Pericarp of Garcinia mangostana

The pericarp of Garcinia mangostana (mangosteen) has been used as a medicinal agent by Southeast Asians for centuries in the treatment of skin infections and wounds. Its main active constituents were xanthones and phenolic compounds. The plant and its metabolites possessed diverse bioactivities.

A methanolic extract of G. mangostana pericarp was subjected to solvent partitioning and chromatographic purification to isolate α-mangostin (1), β-mangostin (2), gartanin (3), garcinone C (4), garcinone D (5), and (+)-2R,3R-taxifolin-3-O-α-L-rhamnoside (astilbin) (6) that were identified by NMR spectral data, as well as comparing with literature data. These compounds were assessed for their in vitro cytotoxic effect against ovarian adenocarcinoma cell line (SKOV-3), hepatic cell line (HepG-2), and colorectal cancer (HCT-116) cell lines using sulforhdamine B (SRB) assay. Doxorubicin was used as a positive control.

All compounds exhibited varying degrees of cytotoxic activity. Garcinone D demonstrated significant cytotoxic potential (IC₅₀ 27.27 ± 2.41 µM) against SKOV-3 cells. While α-mangostin and β-mangostin exhibited cytotoxic activity (IC₅₀ values of 28.1 ± 1.1 µM and 31.9 ± 10.7 µM, respectively) towards HepG-2 cells. Also, β-mangostin and garcinone D demonstrated cytotoxic effects with IC₅₀ values of 56.1 ± 2.5 µM and 44.3 ± 2.5 µM, respectively against HCT-116.

The study highlights the cytotoxic potential of xanthones derived from Garcinia mangostana pericarp. Among the isolated metabolites, garcinone D and α-mangostin emerged as promising lead compounds for further anticancer drug development due to their significant in vitro cytotoxic effects.