Antioxidant Activities of Different Solvent Extracts of Moringa oleifera Seeds Using DPPH Assay

Moringa oleifera (Moringaceae) which grows in the tropical and subtropical regions of the world, has long unani system of medicine with ayurvedic history. The seeds are known to possess high medicinal properties. This study aimed to determine the antioxidant activity of M. oleifera seeds, extracted with different solvents (methanol, ethyl acetate and n-hexane) using 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. This research was carried out using different concentrations of methanol, ethyl acetate, and n-hexane extracts, (5, 10, 15, 20, 25, 30 mg/mL). Vitamin C was also used as standard antioxidant control. The percentage of inhibition and IC50 were measured. The results showed that the DPPH free radicals were scavenged by all seed extracts in a concentration dependent manner. Moreover, the IC50 values for DPPH radicals with methanol, ethyl acetate and n-hexane extract of the M. oleifera seeds were found to be 30.77, 44.77 and 45.04 mg/mL, respectively. Interestingly, the IC50 value of all the extracts revealed very active antioxidant activity but lower than the standard vitamin C due to their IC50 values < 50 mg/mL. The order of activity for all the assay was methanol > ethyl acetate > n-hexane. The results suggested that methanol extract of M. oleifera seeds has the most active antioxidant activity.