新疆红枣主栽品种不同部位的总酚含量和抗氧化活性比较

Comparison of Total Phenolic Contents and Antioxidant Activities of Different Parts of Cultivars Jujube in Xinjiang

以和田玉枣、若羌灰枣、哈密大枣为研究对象,测定枣皮、枣肉、枣核的多酚类物质含量,并比较总抗氧化能力、羟基自由基(·OH)和DPPH·的清除能力。结果表明:果皮中总酚含量大小依次为若羌灰枣(28.10 mg/g)>哈密大枣(26.61 mg/g)>和田玉枣(25.03 mg/g),果肉中总酚含量大小依次为哈密大枣(17.26 mg/g)>若羌灰枣(15.75 mg/g)>和田玉枣(13.82 mg/g),枣核中总酚含量大小相差不大(约2.0 mg/g);在抗氧化能力方面,枣皮中总酚粗提物的总抗氧化能力是最高的,而枣核是最低的,哈密大枣枣肉的总抗氧化能力是优于其他两种红枣,其中在羟基自由基和DPPH自由基清除能力两方面,若羌灰枣枣皮的清除率最高为88.68%、87.40%,和田玉枣枣核的清除率最低为19.85%、9.13%,哈密大枣枣肉的清除率为82.22%、80.08%。抗氧化能力的强弱与红枣多酚类物质含量具有正相关关系。

The contents of polyphenols in jujube peel, jujube pulp and jujube kernel were determined while treating Hetian jujube, Ruoqiang jujube and Hami jujube as the research objects, and the antioxidant capacity were tested, including total antioxidant capacity, free radical scavenging capacity and hydroxyl radical and DPPH·radical. The results showed that the contents of total phenols in peels were in the order of Ruoqiang jujube (28.10 mg/g)> Hami jujube (26.61 mg/g)> Hetian jujube (25.03 mg/g), and the contents in the pulps were in the order of Hami jujube (17.26 mg/g)> Ruoqiang jujube (15.75 mg/g)> Hetian jujube (13.82 mg/g), while those in jujube kernels were almost same (about 2.0 mg/g). In terms of antioxidant capacity, the total antioxidant activity of the crude phenolic extract from the jujube peel was the highest, and that in the jujube kernel was the lowest. The antioxidant capacity of the jujube pulp of Hami jujube was superior to the other two jujubes, including the hydroxyl radical and DPPH· radical scavenging capacity with highest rates of 88.68 % and 87.40 % respectively, while the scavenging rates of Hetian jujube kernels were 19.85 % and 9.13 %, respectively. Then the scavenging rates of Hami jujube pulp were 82.22 %, 80.08 %. The antioxidant capacity has a positive correlation with the content of polyphenols in jujube.