Evaluation of antioxidant activities of various solvent extracts of Carissa opaca fruits

The chloroform and aqueous fractions of Carissa opaca fruit, a traditional medicinal fruit in Pakistan possessed a high amount of total phenolic and flavonoid contents as compare to other solvent fractions with potent antioxidant activities in scavenging DPPH, superoxides, hydroxyl, hydrogen peroxide, ABTS radicals, and had strong iron chelating activity. On the other hand, the ethyl acetate fraction showed the highest inhibition of beta-carotene linoleic acid peroxidation and phosphomolybdate assay. A high correlation coefficient existed between EC50 values of DPPH, superoxides, hydroxyl, hydrogen peroxide, ABTS radicals, total phenolics and flavonoids, but a non significant correlation was found in the case of iron chelaters, beta-carotene and phosphomolybdate assay. This study verified that the chloroform and aqueous fractions have strong antioxidant activities which were correlated with its high level of phenolics and flavonoids. These fractions can be used as a source of potential antioxidant or functional food material. (C) 2010 Elsevier Ltd. All rights reserved.