Determination of antioxidant activity, total phenolic and flavonoid contents in leaves, stem and roots of Uraria picta Desv

Abstract

Uraria picta Desv. belonging to family Leguminosae: Papilionoidae is one of the important constituent of "Dashmoolarista", a well-established Ayurvedic drug of Indian system of medicine. The objectives of the present study were to determine the free radical scavenging activity, total phenolic and flavonoid contents in leaves, stem and roots of U. picta. Powdered samples of leaves, stem and roots were subjected to successive extraction with solvents of increasing polarities i.e. Ethanol, Water: Ethanol (Aqua-alcoholic) (20: 80) and Water (aqueous) using soxhlet apparatus. Total phenol, flavonoid and antioxidant activity were determined by using Folin-Ciocalteau method, aluminum chloride colorimetric technique and DPPH free radical scavenging methods respectively. The results exhibited the maximum phenolic (1.991±0.299%) and flavonoid (2.865±0.11%) contents in ethanolic extract of leaves. For stem, the highest phenolic content (1.208±0.115%) and highest flavonoid content (22.189±2.7%) were detected in aqueous and ethanolic extracts respectively. For roots, both the maximum phenolic (3.554±0.004%) and flavonoid (0.497±0.507%) contents were found in Aqua-alcoholic extract of roots. The ethanolic extracts of leaves and stem and aqueous extract of roots were found to contain the lowest IC 50 and hence, the maximum antioxidant activity. Based on the findings, it can be concluded that among the different extracts of leaves, stem and roots of U. picta, the ethanolic extracts of leaves and stem and aqueous extract of roots exhibited the more promising antioxidant activity due to the presence of phenolic and flavonoid compounds.