Chen X N, Fan J F, Yue X, Wu X R, Li L T
College of Food Science & Nutritional Engineering, China Agricultural University, 17 Qinghua Dong Lu, Haidian, Beijing, 100083, China.
J Food Sci. 2008 Jan;73(1):C24-8. doi: 10.1111/j.1750-3841.2007.00587.x.
The Mopan persimmon (Diospyros kaki L. cv. Mopan) is the major cultivar of astringent persimmon in northern China. This study investigates the radical scavenging activity against ABTS and DPPH radical, and the content of total and individual phenolics (catechin, epicatechin, epigallocatechin, chlorogenic acid, caffeic acid, and gallic acid) with apple, grape, and tomato as controls. The radical scavenging activities against ABTS and DPPH radicals of the Mopan persimmon are 23.575 and 22.597 microm trolox eq/g f.w., respectively. These findings suggest that the Mopan persimmon's antioxidant activity is significantly (P < 0.05) stronger than that of reference materials. The Mopan persimmon showed the highest content of total phenolics among the 4 materials tested. Significant correlations (R(2)= 0.993, P < 0.05, ABTS radical; R(2)= 0.980, P < 0.05, DPPH radical) are found between the total phenolics and the radical scavenging activities. The total content of these 6 kinds of phenolics (catechin, epicatechin, epigallocatechin, chlorogenic acid, caffeic acid, and gallic acid) is significantly correlated (R(2)= 0.831, P < 0.05, ABTS radical; R(2)= 0.745, P < 0.05, DPPH radical) with the individual radical scavenging activity of the 4 materials, although the total content of the 6 phenolics accounts for no more than 20% of the total phenolics in the Mopan persimmon. Gallic acid exhibits the strongest antioxidant activity in all 6 kinds of phenolics and its content is the largest in the Mopan persimmon, presumably being responsible for its much higher antioxidant activity as compared to apple, grape, and tomato.
磨盘柿（Diospyros kaki L. cv. Mopan）是中国北方涩柿的主要栽培品种。本研究以苹果、葡萄和番茄为对照，研究了磨盘柿对ABTS和DPPH自由基的清除活性以及总酚和各单体酚（儿茶素、表儿茶素、表没食子儿茶素、绿原酸、咖啡酸和没食子酸）的含量。磨盘柿对ABTS和DPPH自由基的清除活性分别为23.575和22.597微摩尔Trolox当量/克鲜重。这些结果表明，磨盘柿的抗氧化活性显著（P<0.05）强于参考材料。磨盘柿在所测试的4种材料中总酚含量最高。总酚与自由基清除活性之间存在显著相关性（R(2)=0.993，P<0.05，ABTS自由基；R(2)=0.980，P<0.05，DPPH自由基）。这6种酚类物质（儿茶素、表儿茶素、表没食子儿茶素、绿原酸、咖啡酸和没食子酸）的总含量与4种材料各自的自由基清除活性显著相关（R(2)=0.831，P<0.05，ABTS自由基；R(2)=0.745，P<0.05，DPPH自由基），尽管这6种酚类物质的总含量在磨盘柿总酚中所占比例不超过20%。没食子酸在所有6种酚类物质中抗氧化活性最强，且在磨盘柿中含量最高，这可能是其抗氧化活性比苹果、葡萄和番茄高得多的原因。
