Antioxidant and free radical scavenging properties of an aqueous ripe fruit extract of Borassus aethiopum (M.) FWTA.

Abstract

The palmyra palm, sometimes called the African fan palm, Borassus aethiopum , is an important food source in Ghana and other African countries. The present study was aimed at investigating the possible antioxidant properties of the aqueous fruit extract of this plant. The total phenolic content was assessed by the Folin-Ciocalteau assay, the antioxidant capacity assayed by the phosphomolydbenum method whereas the antioxidant activity was measured by the ability of the extract to scavenge DPPH (1, 1-diphenyl-2-picryl-hydrazyl) radicals. Also, the ability of the extract to inhibit lipid peroxidation was established using the linoleic acid autoxidation assay. The results indicate that the extract (0.1-10 mg/ml) contains phenolic compounds which may be responsible for the antioxidant properties since the coefficient of correlation between the total phenolic content and the total antioxidant capacity was high (r 2 =0.9912). The n-propyl gallate (0.001-0.03 mg/ml), a reference antioxidant and the extract exhibited concentration-dependent free radical scavenging activity. The extract also inhibited concentration dependently the lipid peroxidation of linoleic acid. These findings suggest that the fruit extract of Borassus aethiopum contains antioxidant principles and its use as health supplement in alleviating oxidative stress can be exploited. Key words: Borassus aethiopum , Folin-Ciocalteau, phosphomolydbenum, 1, 1-diphenyl-2-picrylhydrazyl, n-propyl gallate.