Antioxidant capacity of straweberry polyphenols from Tucumán

Abstract

Free radicals are generated in the body by normal metabolic activity as well as lifestyle factors such as smoking, exercise and diet and have been associated in the causation and progression of several chronic diseases. The aim of this work was to investigate the antioxidant capacity of two varieties of strawberry juices and their relationship with the phenolic compound content. Total phenolics concentration was based on the procedure of Singleton and Rossi, flavonoid and phenolic acids concentration was determined using the method descript by Zoecklein (1990). The antioxidant activity was determined by FRAP, DPPH and ABTS methods in juices and pure phenolic compounds. The total phenolic concentrations in albion and camarosa juices were 1188.4 and 1257.7 mg GAE/l, respectively. The clarification process was effective to remove approximately the 80% of phenolic compounds. In both juices, flavonoid fraction was about 75% higher than phenolic acid fraction. With camarosa and albion strawberries juices were observed a high ferric reducing power, ABTS and DPPH radical scavenging activity. Gallic acid shows the highest antioxidant activity between individual compounds. Ours results indicate that phenolic compounds are the major contributors of these capacities and permit propose these juices as new sources of safe natural antioxidants.