In Vitro Elucidation Free Radical Scavenging Activity of Flavonoids Extracted From Leaves and Flowers of Arbutus Pavarii (Ericaceae)

Increasing attention has been paid to the use of natural antioxidants, particularly of plant origin in order to substitute synthetic antioxidant due to their negative health effects.  The aim of this study was to screen the  flavonoid extracted from leaves and flowers of A. pavarii and their mixture of to show any antioxidant activity in vitro. the antioxidant and free radical scavenging activity were determined by several standard methods using spectrophotomer.  Flavonoid extracts showed higher reducing ability in comparison with ascorbic and BHA.  It was found that flavonoids extracted from leaves have the most activity to reduce the DPPH with an IC50 of 0.625mg/mL; more effective than others.  This extract also exhibited fairly good antioxidant activity by inhibiting the generation of OH (IC50= 0.625mg/mL) and  NO radicals (IC50= 1.25mg/ml). The inhibition of lipid peroxidation was recorded in flavonoids extracted from leaves (60%). Synergism was the main effect among the combined extract, C3 (L:F; 2: 1).  Three types of interactions (synergistic, additive and negative synergistic effect) were observed.