E3 Journal of Biotechnology and Pharmaceutical Research

E3 Journal of Biotechnology and Pharmaceutical Research Vol. 4 (1) pp. 14-21, January 2013; © E3 Journals; ISSN 2141-7474

Antioxidant activity and GC-MS analysis of Grewia optiva

Abstract

In this study, total antioxidant capacity (TAC) of extracts of Grewia optiva Leaves (GOL) was investigated. The antioxidant components were initially extracted in methanol and subjected to partitioning in solvents of different polarity. Using ABTS•+ decolorization assay and FRAP assay GOL extracts showed a wide range of antioxidant activity. Trolox equivalent antioxidant capacity (TEAC) values for different fractions ranged from 0.09-0.915 mM of Trolox equivalents for GOL extracts. FRAP values for different fractions ranged from 22.64-43.28 mg/L FeSO4 equivalents. Using TPC Assay the amount of total phenolics for different fractions of GOL ranged from 10.57-78.37 mg/L Gallic acid equivalents. Employing inhibition of lipid peroxidation assay by ferric thiocyanate method, the extracts showed inhibition of lipid peroxidation comparable to Trolox. The Superoxide percentage scavenging activity for different fractions of GOL ranged from 4%-12%. Percentage bound iron for metal chelating activity varied from 3.69%-11.96% for GOL. On the basis of these results obtained here GOL may be considered as a rich source of antioxidant

Keywords: Antioxidants, ABTS radical cation, Free radicals, TEAC, Reactive oxygen species