Abstract

BIOACTIVE FRACTIONS AND POLYPHENOLS OF THE ETHANOL EXTRACT OF SWIETENIA MAHOGANI LEAVES

Ola Mohamed Mousa*, Marwa Yousry Issa, Hesham Ibrahim El-Askary, Soheir Mohamed El Zalabani and Amani A. Sleem

Abstract

The ethanol (90%) extract of Swietenia mahogani L. Jacq. leaves wasfractionated with solvents of increasing polarities. The antioxidant andhepatoprotective activities of all successive extractives were evaluated.The highest efficiency was, in most cases, observed for the ethylacetate-soluble fraction. Repeated column chromatography of thisfraction and sub-fractions derived therefrom, on different stationaryphases (Polyamide and Sephadex LH-20), allowed the isolation of sixknown polyphenols, previously unreported in the genus. Isolatedcompounds namely: (+) catechin, quercetin-3-O-β-D-glucopyranoside(isoquercitrin), 3-caffoeylquinic acid (neochlorogenic acid), quercetin-3-O-β-D-galactopyranoside (hyperoside), quercetin and kaempferolwere identified through physico-chemical and spectral analyses and bycomparison with published data. The antioxidant activity of the threefirst isolates was also assessed and found significant.

Keywords: Swietenia mahogani, leaves, antioxidant, hepatoprotective, polyphenols.