Comparison of antioxidant capacities of extracts from five cultivars of Chinese jujube

The antioxidant capacities of extracts from five cultivars of Chinese jujube were evaluated and compared the antioxidant activities of α-tocopherol. The data indicated that the antioxidant capacity differed in cultivars. The antioxidant activities, scavenging effect on the 2,2-diphenyl-1-pycril-hydrazyl (DPPH) radical and reducing power of extracts decreased in the order of Zizyphus jujuba cv. jinsixiaozao, Zizyphus jujuba cv. yazao, Zizyphus jujuba cv. jianzao, Zizyphus jujuba cv. junzao, Zizyphus jujuba cv. sanbianhong. The antioxidant activities of extracts from Zyphus jujuba cv. jinsixiaozao, Zizyphus jujuba cv. yazao and Zizyphus jujuba cv. jianzao were stronger than α-tocopherol. Significant differences (p < 0.05) were found between α-tocopherol and both Zyphus jujuba cv. jinsixiaozao and Zizyphus jujuba cv. yazao, while no significant differences (p > 0.05) were found between α-tocopherol and Zizyphus jujuba cv. jianzao. Additionally, no correlation between total phenolic contents and antioxidant capacities of extracts from five cultivars of Chinese jujube was found.