Contribution of phenolic compounds, ascorbic acid and vitamin E to antioxidant activity of currant (Ribes L.) and gooseberry (Ribes uva-crispa L.) fruits

Berries of four gooseberry (Ribes uva-crispa L.) cultivars of Invicta, Rixanta, Karat and Black Negus and five currant (Ribes L.) cultivars of NS 11, Focus, Ben Gairn, Otelo and Viola were evaluated as potential sources of bioactive compounds with extraordinary antioxidant activity. Their total phenolic, flavonoid and anthocyanin contents were determined in the range of 3.52-30.77 g GA.kg^-1, 2.83-17.35 g RE.kg^-1 and 0.03-186.12 mg COG.100 g^-1, respectively. Furthermore, quantification of phenolic compounds and vitamins was established by high-performance liquid chromatography-diode array detection. Flavonoids were the most abundant phenolic substances in the range of 345.0-3726.5 mg.kg^-1. Ascorbic acid and vitamin E were established in the amounts of 6.2-14.04 g.kg^-1 and 0.43-12.85 mg.kg^-1, respectively. Considering all analyzed factors and antioxidant activities determined by various methods (DPPH, ACW and ACL), red gooseberry Black Negus and black currant Otelo were the most significant cultivars.