Effect of fractionation on antiradical efficacy of ethyl acetate extract of Terminalia chebula Retz.

Abstract

There is currently an upsurge of interest in phytochemicals as new sources of natural antioxidants. The aim is to use them in foods and pharmaceutical preparations in order to replace synthetic antioxidants, which are being restricted due to their potential health risks and toxicity. The relative levels of antioxidant activity and the total phenolic content of ethyl acetate extract/fractions of Terminalia chebula have been determined using DPPH, Deoxyribose, Reducing power, Chelating power, Lipid peroxidation, DNA nicking assay and the Folin- Ciocalteu colorimetric method. There was a positive linear correlation between antioxidant activity and total phenolic content of ethyl acetate extract/fractions. Thus, it was concluded that phenolic compounds were the predominant antioxidant components in the fruits of T. chebula. The extract was prepared by maceration method at room temperature and further fractionated with ethyl acetate and water. It was observed that the free radical scavenging activity of fractions was comparatively more as compared to their crude extract and ethyl acetate fraction showed the maximum effect in all assays. The percent inhibition with ethyl acetate fraction (EAF) of ethyl acetate extract was observed to be 71.5, 90.0, 75.1, 74.3 and 77.6% in DPPH, site specific and non-site specific deoxyribose, chelating power and lipid peroxidation assays, respectively at maximum concentration tested. Key words: Terminalia chebula, oxidative stress, phytochemicals, antioxidants, lipid peroxidation.