Comparative analysis of vitamin C content and antioxidant activity of some fruits extracts

Abstract

In this work was determined ascorbic acid concentration in orange fruits and plums as well as in aqueous, alcoholic and acetonic extracts obtained from them, at the same time evaluating the antioxidant activity of these extracts. Ascorbic acid content was determined by iodometric method and antioxidant activity was quantified by free# radical 2,2#diphenyl#1#picrylhy drazyl (DPPH) method. We notice a rich content of ascorbic acid both in the orange pulp (984,00 mg/100g) and in plums (870,16 mg/100g). Between obtained extracts, those in acetone are the richest in vitamin C, followed by those in water and then the alcoholic extracts. The highest concentration of ascorbic acid was determined in acetonic extracts of orange pulp (52.84 mg/100ml). Lowest content of vitamin C was recorded for alcoholic orange extract (26.42 mg/100ml). Acetonic extract of orange, which has the highest content of ascorbic acid, has the strongest antioxidant activity (the highest reaction speed of DPPH solution in the presence of this extract: v=3.886 µM/s) and the lowest antioxidant activity is for alcoholic extract of orange (v=2.007 µM/s), which presents the lowest concentration of vitamin C.