Phytochemical screening and in vitro antioxidant activity of various Punica granatum l. Peel extracts from Algeria: A comparative study

Abstract

© 2014, Springer-Verlag France. This study was undertaken to evaluate the correlation between total phenolic and flavonoid contents and antioxidant activity of various extracts of Punica granatum peel using ferric reducing antioxidant power (FRAP) and radical scavenging methods (DPPH). Preliminary phytochemical screening shows that the major constituents of total extracts are tannins and flavonoids. Phenolic and flavonoid contents were determined using spectrophotometric methods of hydromethanolic and aqueous-acetone crude extracts and their fractions, showing a high content in ethyl acetate fractions of each extract (597.08 ± 3.9 and 602.8 ± 0.0 mg GAE/gE respectively) followed by n-butanol fractions of each extract (413.6 ± 1.48 and 417.56 ± 5.3 mg EQC/gE respectively). Crude extracts showed the lower contents than the ethyl acetate and n-butanol fractions. FRAP method revealed that the ethyl acetate fraction from hydromethanolic extract showed the highest power to reduce iron followed by n-butanol fraction from aqueousacetone extract. In comparison with ascorbic acid (EC50= 1.09 μg/mL), the ethyl acetate fractions of each extract showed highest antioxidant activity (EC50= 1 μg/mL and EC50= 0.75 μg/mL respectively) to scavenge DPPH free radical. These results indicated that antioxidant activity was correlated with the higher content of total phenolics and flavonoids of Punica granatum peel extracts.