Biologically-Guided Isolation Of Leishmanicidal Secondary Metabolites From Euphorbia Peplus L.

Leishmaniasis is a major worldwide health problem, highly endemic in developing countries. The incidence of leishmaniasis has increased after the emergence of AIDS [1]. In a research project designed to search for biologically active compounds from natural origin; twenty extracts from fifteen plants growing in Egypt have been investigated for in vitro leishmanicidal activity against Leishmania donovani promastigotes. Among the tested extracts, the methanol extract of Euphorbia peplus herb exhibited a powerful antileishmanial activity as it produced 100% inhibition of growth with activity similar to amphotericin B. The total extract was subjected to biologically-guided fractionation, followed by phytochemical exploration of the active n-hexane fraction (which produced 75% inhibition of growth) that led to isolation of four compounds; simiarenol (1), 1-hexacosanol (2), β-sitosterol (3), and β-sitosterol-3-O-glucoside (4) with compounds 1 and 4 being reported for the first time in E. peplus herb. Structure elucidation was aided by 1D and 2D NMR techniques.

References: [1] Rocha LG, et al. (2005) Phytomedicine; 12:514 – 35.