Antioxidant activities of the extracts and isolated compounds from <i>Treculia africana</i> (Decne) leaf

Abstract

Antioxidant activities of the crude leaf extract and four solvent fractions: hexane, dichloromethane, ethyl acetate and butanol fractions from Treculia africana leaf were carried out to determine their potentials and suitability in the management of oxidative diseases. Different antioxidant assays (TAC, DPPH, FRAP, inhibition of NO, metal chelating ability were carried out separately to study the activities of the samples. In addition, the total phenolic content of the extracts was evaluated. Bioassay guided fractionation of the most active fraction (ethyl acetate fraction) using repeated column chromatography on Silica gel and Sephadex LH-20 resulted in the isolation of apigenin-6-C-glucopyranoside (isovitexin) (1) and 2,3-dihydrokaempferol-3-O-glucopyranoside (2). The crude extract, solvent fractions and the compounds (1-2) exhibited strong to moderate antioxidant activities in all the tested assays. The two compounds isolated from T. africana are reported for the first time from this plant species. The activities demonstrated by the extracts and isolated compounds could provide rationale for the ethnomedicinal uses of the plant in folk medicine for the management of oxidative stress related diseases.

Keywords: Treculia africana, Moraceae, Antioxidant Activity, oxidative stress