Dose dependency of anti-oxidant activity of quercetin glycosides of Annona cherimola

Chemical diversity in plants serves as a rich source of medicinal products because of their precious therapeutic activities and also low toxicity profile. In plants there are a wide variety of naturally occurring anti-oxidants, which are different in their composition, physical and chemical properties, mechanism and site of action. Hence screening of different plant extracts is being done by measuring the anti-oxidant activity through various in vitro and in vivo models. Through preliminary phytochemical screening the plant Annona cherimola was reported to contain alkaloids, flavonoids, saponins, tannins, carbohydrates, proteins phenolic compounds, phytosterols and amino acids [1, 2] . A study was carried out to isolate the constituents of leaves of A.cherimola and elucidated the structures of them by using spectroscopic methods and also evaluated their pharmacological activity by both in vivo and in vitro methods [1, 2, 3]. On identifying the anti-oxidant and anti-inflammatory potential of the chemical constituents isolated from the methanol extract of leaves of A.cherimola [4], further investigations are conducted to trace the effect of dose variation on the anti-oxidant activity of the three quercetin glycosides (flavonoids) isolated (figures: 1, 2 & 3). Journal of Comprehensive Pharmacy