Antioxidant potential and total phenolic content of Serbian red clover cultivars

Abstract

Red clover (Trifolium pratense) is rich in phytoestrogens as well as other phenolic substances which contribute to its antioxidative properties. Still, its antioxidative potential has not been thoroughly investigated. The aim of this study was to determine radical scavenging capacity and total phenolic content of red clover cultivars from Serbia observing different plant parts. Leaves, stems and flowers from four red clover cultivars (Kolubara, Una, Avala, K17) were grounded and extraction with water, 3M HCl and ethanol was performed. Radical-scavenging capacity was measured by reaction with the stable DPPH (2,2-diphenyl-1-picrylhydrazyl) radical and calculation of the amount necessary to decrease initial DPPH concentration by 50% (IC50). Total phenolic content (TPC) was determined according to the Folin-Ciocalteu method and expressed as gallic acid equivalents (GAE). Antioxidant potential and TPC of leaves and flowers were not statistically different, but on average, flower extracts had the highest antioxidant activity (IC500.087 mg/ml) and leaf extracts the highest TPC (30.30 mg/g GAE).