Chemical and Bioactivity Studies on Garcinia mangostana

Author

JOAZAIZULFAZLI JAMALIS & MUHAMMAD SUM IDRIS

Proceeding

The 21st Annual Seminar of the Malaysian Natural Product Society.(Herbal Medicine:Natural Products Society), Palm Garden, Putrajaya Malaysia.

Date

22/11/2005

Keyword

Guttiferae, Garcinia mangostana, mangosteen, mangostin, methylation, acetylation

Abstract

Chemical investigation on the fruits hull of Garcinia mangostana has been carried out. The samples were extracted with petroleum ether followed by ethyl acetate. Purification of the crude extracts was carried out by using chromatographic techniques such as vacuum and gravity column chromatography. Spectroscopic data analysis showed that the main compound was mangostin.  Maclurin and isomangostin were isolated as minor compounds. Methylation of mangostin with methyl iodide, acetone and K2CO3 gave dimethylmangostin and acetylation of mangostin with acetic anhydride in triethylamine in the presence of catalyst DMAP gave triacetoxymangostin. The isolated and derivatised compounds were characterized by spectroscopic techniques such as proton and carbon-13 nuclear magnetic resonance (1H-NMR and 13C-NMR) and infrared (IR).  Brine shrimps lethality test on the samples showed that maclurin was the most toxic compound (ED50 0.17), followed by  EtOAc extract with ED50 value of 1.21.