Antioxidant capacity and chemical properties of selected barberry (Berberis vulgaris L.) fruits

Six purple-black barberry accessions (Berberis vulgaris L.) were obtained from various sites in Sivas province of Turkey. Fruits were analyzed for their total phenolic (TP), total monomeric anthocyanin (TMA) contents and for their antioxidant capacity by the ferric reducing antioxidant power (FRAP) and TEAC assays. Sugar and organic acid composition were also determined by HPLC. TP and TMA contents were measured using the Folin-Ciocalteu reagent and pH differential methods, respectively. Variability between the accessions was not high. Variability among accessions was greatest for FRAP content (C.V. 17.9%); individuals ranged from 41.0 to 65.6 μmol TEㆍg-¹ on a fresh weight basis. Variation among the accessions was also evident for TP, TMA, and TEAC values (C.V. 16.21%, 14.85%, and 7.13%, respectively). The major sugars of barberry fruits were glucose (8.84 gㆍ100 mL-¹) and fructose (6.12 gㆍ100 mL-¹) and dominant organic acids were malic (7.59 gㆍ100 mL-¹) and citric (1.34 gㆍ100 mL-¹). Within this limited study of six different accessions, chemical profile and antioxidant capacity of barberry fruits have rich source of natural antioxidant substances.