COMPARATIVE ANTIOXIDANT ACTIVITY AND BRINE SHRIMP LETHALITY BIOASSAY OF DIFFERENT PARTS OF THE PLANT- ACACIA AURICULIFORMIS

The present study was undertaken to evaluate and compare the antioxidant activity and brine shrimp lethality bioassay of different parts (leaf and bark) of the plant Acacia auriculiformis. DPPH radical scavenging and NO scavenging capacity were measured for the determination of antioxidant activity. Ethyl acetate fraction of bark was found to possess highest DPPH radical scavenging activity with IC₅₀ value of 7.80 µg/ml followed by methanol extract of leaf (IC₅₀ value of 7.95 µg/ml). The IC₅₀ value of standard ascorbic acid was 33.77 µg/ml. Incase of NO scavenging activity, n-hexane fraction of root found to have highest scavenging activity with IC₅₀ value of 1.75 µg/ml followed by ethyl acetate fraction of leaf (IC₅₀ value of 3.35 µg/ml). The IC₅₀ value of standard ascorbic acid was 71.06 µg/ml. When compared with other fractions, the methanol fraction of leaf and bark had highest cytotoxic activity with LC₅₀ value of 0.55 and 0.79 µg/ml respectively. This was followed by ethyl acetate fraction of leaf with LC₅₀ value of 0.95 µg/ml. The standard vincristine sulfate had LC₅₀ value of 0.52 µg/ml. Thus, this study suggests that leaf and bark of A. auriculiformis may be a potential source of antioxidant and cytotoxic agents