Total phenolics and antioxidant activity of jujube (Zizyphus jujube Mill.) genotypes selected from Turkey

We determined the total phenolic content and antioxidant activity of methanol extracts from fifteen selected jujube genotypes endogenous to the Mediterranean region of Turkey. Total phenolic content of the fruits was analyzed by Folin-Ciocalteu colorimetric method, while the total antioxidant activity was analyzed using the beta-carotene bleaching, ferric ion reducing antioxidant power (FRAP) and 2,2-diphenil-1-picrylhydrazyl radical scavenging capacity (DPPH) assays. The highest total phenolic content was observed in MHS 6 and MHS 7 genotypes (42 and 40 mg gallic acid equivalent (GAE) g(-1) dry weight (DW)), while the lowest content was found in MHS 5 and MHS 14 (28 and 25 mg GAE g(-1) DW). MHS 13 was among the genotypes with the highest antioxidant capacity in all three methods tested (1237 mu mol g(-1) in FRAP, 83% in beta-carotene bleaching method and 99% in DPPH). The present study demonstrates the potential value of jujube genotypes for pharmaceuticals and nutrition.