乌龙茶的抗氧化活性。

Antioxidative activities of oolong tea.

作者信息

Zhu Qin Yan, Hackman Robert M, Ensunsa Jodi L, Holt Roberta R, Keen Carl L

机构信息

Departments of Nutrition and Internal Medicine, University of California, Davis, California 95616-8669, USA.

出版信息

J Agric Food Chem. 2002 Nov 6;50(23):6929-34. doi: 10.1021/jf0206163.

DOI:10.1021/jf0206163

PMID:12405799

Abstract

While the antioxidative properties of green and black tea have been extensively studied, less attention has been given to these properties in oolong tea. The reducing powers, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activities, the amount of total phenolic compounds, the inhibitory effect on FeCl(2)/H(2)O(2) (Fenton reaction system)-induced DNA damage, and the inhibitory effect on erythrocyte hemolysis of an oolong tea water extract (OTE) were evaluated in the present study. The OTE was found to have strong antioxidative activities in all of the model systems tested. When the OTE was separated into different fractions according to molecular weight, it was found that the fractions with higher amounts of phenolic compounds (lower molecular weight) have stronger antioxidative activities. The present results support the concept that oolong tea contains several low molecular weight antioxidants that may have health promotion activities.

摘要

虽然绿茶和红茶的抗氧化特性已得到广泛研究，但乌龙茶的这些特性却较少受到关注。本研究评估了乌龙茶水提取物（OTE）的还原能力、2,2-二苯基-1-苦基肼（DPPH）清除活性、总酚类化合物含量、对FeCl₂/H₂O₂（芬顿反应体系）诱导的DNA损伤的抑制作用以及对红细胞溶血的抑制作用。结果发现，OTE在所有测试的模型体系中均具有较强的抗氧化活性。当根据分子量将OTE分离成不同组分时，发现酚类化合物含量较高（分子量较低）的组分具有更强的抗氧化活性。目前的结果支持了乌龙茶含有几种可能具有促进健康活性的低分子量抗氧化剂这一观点。