Abstract

DETERMINATION OF ANTIOXIDANT ACTIVITY AND HPLC PROFILE OF EUPHORBIA COTINIFOLIA LINN. LEAF EXTRACT GROWING IN BANGLADESH

Hemayet Hossain*, Shaikh Emdadur Rahman, Proity Nayeeb Akbar, Tanzir Ahmed Khan, Md. Mahfuzur Rahman, Ismet Ara Jahan

Abstract

Antioxidant properties and HPLC profiling of polyphenolic contents of ethanol extract of Euphorbia Cotinifolia leaves were evaluated. Antioxidant activity was determined by ABTS radical scavenging activity, with an IC50 value of 95.60 ± 0.19 μg/ml, and maximum absorbance of reducing power of 0.0996 ± 0.013 at 250 μg/ml. The total antioxidant capacity, and total phenolic and flavanoid contents were also determined and were found in the range 328.7 ± 3.01 mg of ascorbic acid/g, 64.64 ± 2.14 mg/g of gallic acid, and 81.72 ± 6.05 mg/g of quercetin equivalent, respectively. Polyphenolic compounds like catechin, vanillic acid, p-coumeric acid, rutin hydrate and quercetin were obtained in the extract by reverse-phase HPLC and varied within the range of 80.14 ± 1.75, 3.09 ± 0.12, 1.22 ± 0.05, 27.09 ± 1.09 and 1.73 ± 0.03 mg/100 g extract, respectively. Due to the higher phytochemical content and significant antioxidant activity, the leaf extract of E. cotinifolia was selected as a valuable plant extract. A relationship between the polyphenolic compounds present in E. cotinifolia and its antioxidant activity can be suggested.

Keywords: Euphorbia cotinifolia, HPLC, caffeic acid, vanillic acid, p-coumeric acid, reducing power assay.