ATIHEMOLYTIC AD ATIOXIDAT ACTIVITY OF HIBISCUS ESCULETUS LEAVES

Summary Antioxidant activity of leaves of Hibiscus esculentus was investigated employing different models in vitro assay systems. Extract showed good antioxidant activity. IC 50 for DPPH radical.scavenging activity was 245 ± 12.2 �g ml .1 . Extract showed weak nitric oxide.scavenging activity between 0.1 and 1.6 mg ml .1 . The leaves extract had show good reducing power that was comparable with Vitamin C (p< 0.01). Also, extract showed weak Fe 2+ chelating ability. IC 50 was 1.24 ± 0.09 mg ml .1 . H. esculentus leaves Extract exhibited low antioxidant activity in linoleic acid model but were capable of scavenging hydrogen peroxide in a concentration dependent manner. Also, extract showed potent activity in inhibition of rat erythrocyte hemolysis. IC 50 was 274.3 ± 11 �g ml .1 . The total amount of phenolic compounds in extract was determined as gallic acid equivalents and total flavonoid contents were calculated as quercetin equivalents from a calibration curve.