Abstract

Fringe tree (Chionanthus virginicus L.) is used as a raw material by pharmaceutical industries for the preparation of homeopathy tinctures. In this study, antioxidant activity of methanol extract (MEFT) and ethylacetate extract (EEFT) from root bark of fringe tree (C. virginicus L.) were evaluated. 2,2-Azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging, 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH·) scavenging, superoxide anion (O₂^•-) radical scavenging, total antioxidant activity, reducing activity, hydrogen peroxide (H₂O₂) scavenging and ferrous metal chelating activities were for used antioxidant evaluation of MEFT and EEFT. The both extracts neutralized the activities of radicals and inhibited the peroxidation reactions of linoleic acid emulsion. Total antioxidant activity was measured according to ferric thiocyanate method. Butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), a-tocopherol and trolox, a water-soluble analogue of tocopherol, were used as the reference antioxidant compounds. MEFT and EEFT showed 69.4, 79.3, 72.3 and 83.7% inhibition on lipid peroxidation of linoleic acid emulsion, respectively, at the 10 and 20 µg/mL concentrations. On the other hand, 20 µg/mL of α-tocopherol, trolox, BHA and BHT exhibited 54.7, 20.1, 74.4 and 71.2% inhibition on peroxidation of linoleic acid emulsion, respectively. Also, MEFT and EEFT have effective DPPH•, ABTS^•+ and superoxide anion radicals scavenging, hydrogen peroxide scavenging, total reducing power and metal chelating on ferrous ions activities.

Key words: Chionanthus virginicus; oleaceae; antioxidant activity; fringe tree; radical scavenging, metal chelating.