Microwave Assisted Extraction, Fractionation, Total Phenolic and Flavanoid Estimation and antioxidant potential of Annona reticulata Leaves

The present study focuses on the microwave assisted extraction of Annona reticulata leaves in ethanol. The extract obtained was subjected to column chromatography and the fractionation was done to get different fractions. Preliminary phytochemical screening was done and the fractions were subjected to total phenolic and flavanoid content estimation. The crude extract contained 502 mg GAE/100g of phenolic content and among the fractions AM8 contained the maximum amount of phenolic content that is 360 mg GAE/100g. The flavanoid content present in the crude extract of the Annona reticulata was found to be 127mg QE/100g. Among all the tested fractions, the fraction AM8 showed more flavanoids i.e. 112 mg QE/100g and 118 AN/100g. The antioxidant activity has been studied in-vitro by using DPPH, hydrogen peroxide assay. DPPH, H₂O₂ and Nitric-oxide scavenging effect of Annona reticulata L. leaf extracts were found to be dose dependant with maximum inhibition at highest concentration. Methanolic extract of the leaves of Annona reticulata Linn. is found to have most potent anti-oxidant activity in DPPH, H₂O₂ Radical scavenging methods. IC50 value DPPH and H₂O₂ inhibition of methanolic extract at highest concentration (400μg/ml) are 62.58 ± 1.15, 68.27 ± 1.05 and 64.01 ± 1.02. The results suggest that all the tested extracts are having antioxidant property, but the methanol is having significantly higher flavonoid and phenol content. Due to presence of higher flavonoid and phenol content in methanol, it may be considered as the fraction with better pharmacological property in comparison to other tested extracts.