Isolation And In Vitro Antimalarial Activity Of Hexane Extract From Thai Picrasma Javanica Bl Stembark

摘要

The in vitro antimalarial activities against Plasmodiumfalciparum Kl of four extracts from the stembark of Picrasma javanica Bl; ie water, methanol, chloroform and hexane extracts were studied using a modification of the [~3H]hypoxanthine incorporation method. It was found that the hexane extract showed in vitro antimalarial activity with IC_(50) of 3.3 mug/ml, The extract was further fractionated using quick column chromatography, resulting in ten fractions. Fraction V was the most effective against P.. falciparum Kl with IC_(50) of 4.4 mug/ml. Further isolation of fraction V using a column chromatographic technique provided six fractions According to !H- and ~(13)C-NMR spectra, it could be concluded that the major compound in fraction V-3 was p-sitosterol. Unfortunately, the antimalarial activity of P-sitosterol could not be determined because of its low solubility in DMSO. However, fractions V-2 and V-4 still showed in vitro antimalarial activities with IC_(50) of 2.8 and 3.4 mug/ml, respectively. The further fractionation of these two active fractions could lead to promising candidates as antimalarial agents.