POTENTIAL IN VITRO ANTIOXIDANT AND PROTECTIVE EFFECT OF CASSIA FISTULA LINN. FRUIT EXTRACTS AGAINST INDUCED OXIDATIVE DAMAGE IN HUMAN ERYTHROCYTES

Objective: To evaluate the antioxidant potential and protective effect of Cassia fistula Linn. on hydrogen peroxide induced oxidative damage in erythrocytes.Methods: The in vitro antioxidant potency was screened by various established chemical, biochemical and electrochemical techniques. The Chemical assays allowed an evaluation of their total phenolic and flavonoid contents, total antioxidant capacity, reducing power, radical scavenging activities and metal chelating activity. Both, CFE (C. fistula ethanolic extract) and CFA (C. fistula aqueous extract) were analyzed for phenolic acids and flavonoids by HPLC. The biochemical assays were employed to evaluate the lipid peroxidation and protective effect on induced oxidative damage in erythrocytes. Electrochemical measurement of CFE and CFA was determined by cyclic voltammetry.Results: CFE showed strong antioxidant activity as well as >90% protection of erythrocytes. This might be due to the presence of high 464.3 ± 0.02 µg EGA mgˉ1total phenolics and 272.5 ± 0.5 µg EQ mgˉ1 total flavanoids while, CFA showed 75% antioxidant and protective activity possibly due to 250.84 ± 0.25 µg EGA mgˉ1 total phenolics and 195 ± 0.5 µg EQ mgˉ1 total flavonoid content. Moreover, HPLC of CFE and CFA exhibited widely known various good antioxidant molecules such as gallic acid, coumaric acid, ellagic acid, rutin, quercetin, myricetin and kaempferol. The cyclic voltammetric behavior shows the broad peak towards anodic potential represents the antioxidant property of CFE and CFA.Conclusion: The present study clearly indicates that, C. fistula Linn. Fruit is an excellent source of natural antioxidant.Â