Successive solvent extraction and free radical scavenging activity of Azadirachta indica A. juss

Abstract

Background: Plant‑based or plant‑derived drugs occupied 30% of the modern system of medicine. Several trees possess a variety of biologically active compounds. Among them, Azadirachta indica, belonging to the family Meliaceae, plays a vital role as it acts as nature’s pharmacy from several centuries of time. In the path of searching for potential antioxidants from plant origin, different parts of Azadirachta indica have been selected. Aim: Successive solvent extracts of leaves, seeds and root barks of Azadirachta indica A. Juss (neem) were studied for their free radical scavenging activity. Materials and Methods: Extraction capacity of different solvents based on their polarity order was compared and the extracts were subjected to 1‑diphenyl‑2‑picryl hydrazyl (DPPH) free radical scavenging assay. Statistical Analysis: All values were expressed in mean±SEM and correlation coefficient (R2) values obtained from dose response curves were expressed for antioxidant results. Results: The results showed that the highest yields was found with the hydroalcoholic extract of leaves, followed by the hydroalcoholic extract of seeds and methanolic extracts of leaves and seeds, respectively. Free radical scavenging activity of various extracts was determined by measuring 1, DPPH free radical scavenging activity. The results were expressed in terms of IC50 values. The root bark methanol extract was found to exhibit the highest IC50 of 14.82‑μg/ mL at the concentration of 25‑μg/mL. Conclusion: It is concluded that hydroalcohol and methanol are the best solvents to extract the antioxidant compounds from Azadirachta indica. The root bark methanolic extract was found to have the highest free radical scavenging potential against DPPH radical. Key words: Antioxidant activity, Azadirachta indica, 1‑diphenyl‑2‑picryl hydrazyl, neem, root bark methanol extract and leaves hydroalcoholic extract