THE ANTIOXIDANT AND FREE-RADICAL SCAVENGING ACTIVITIES OF TAMARIX BOVEANA AND SUAEDA FRUTICOSA FRACTIONS AND RELATED ACTIVE COMPOUND

Abstract

The antioxidant potentials of the ethyl acetate and the methanolic fractions of the halophytes Tamarix boveana Bunge and Suaeda fruticosa L. were established by using radical-scavenging assays, namely DPPH• scavenging and ABTS•+ scavenging, in addition to total polyphenol content assay. These fractions showed very interesting dose-dependent free radical scavenging properties in all samples. In particular, the ethyl acetate fraction of T. boveana exhibited a strong antioxidant activity toward DPPH and ABTS+ radicals reaching 100 % of inhibition. To search the active principle responsible for this activity, this extract was further fractionated by repeated chromatography on silica gel. Interestingly, Naringenin was found to be responsible for the major share of the unregistered activity in the company of other compounds participating synergistically. An important correlation between antioxidant capacities of the other fractions and their total phenolic contents was revealed.