Antioxidant and free radical scavenging activity of Pithecellobium dulce (Roxb.) Benth wood bark and leaves

Abstract

Background: Several studies are going on worldwide directed towards finding natural antioxidants from plant origin which possess strong antioxidant activity. Objective: The aim of the present study was to study in vitro antioxidant and free radical scavenging activity of Pithecellobium dulce (Roxb.) Benth. Method: Methanol and 70% acetone extracts of wood bark and leaves of Pithecellobium dulce were evaluated for their total phenolic & flavonoid content, antioxidant and radical scavenging activity. Results: Total antioxidant activity (IC₅₀ values) in DPPH assay by methanol extract of bark (MB), acetone extract of bark (AB), methanol extract of leaf (ML) and acetone extract of leaf (AL) shown 150.23 ± 2.8, 16.83 ± 0.38, 250.32 ± 4.8 and 18.30 ± 0.43 μg/ml respectively. The IC₅₀ values for scavenging of free radicals like for hydroxyl, superoxide, nitric oxide, hydrogen peroxide, singlet oxygen and hypochlorous acid by MB, AB, ML and AL were studied. The extract was found to be a good iron chelator. The reducing power was increased with increasing amounts of extract. The MB, AB, ML & AL extracts (5 mg/ml) yielded 0.129 ± 0.11, 0.190 ± 0.14, 0.084 ± 0.24 and 0.115 ± 0.25 μg/ml gallic acid-equivalent phenolic content and 0.43 ± 0.01, 0.23 ± 0.01, 0.90 ± 0.01 and 0.25 ± 0.01 μg/ml quercetin-equivalent flavonoid content respectively. Conclusion: Thus, our findings provide evidence that the methanolic and 70% acetone extracts of P. dulce wood bark and leaves are potential source of natural antioxidants and some extent validated its medicinal potential.