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 was
fractionated with solvents of increasing polarities. The antioxidant and
hepatoprotective activities of all successive extractives were evaluated.
The highest efficiency was, in most cases, observed for the ethyl
acetate-soluble fraction. Repeated column chromatography of this
fraction and sub-fractions derived therefrom, on different stationary
phases (Polyamide and Sephadex LH-20), allowed the isolation of six
known polyphenols, previously unreported in the genus. Isolated
compounds namely: (+) catechin, quercetin-3-O-β-D-glucopyranoside
(isoquercitrin), 3-caffoeylquinic acid (neochlorogenic acid), quercetin-
3-O-β-D-galactopyranoside (hyperoside), quercetin and kaempferol
were identified through physico-chemical and spectral analyses and by
comparison with published data. The antioxidant activity of the three
first isolates was also assessed and found significant.

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