黄酮醇
化学
特罗洛克
Trolox当量抗氧化能力
阿布茨
抗氧化剂
儿茶素
食品科学
氧自由基吸收能力
高效液相色谱法
多酚
表儿茶素没食子酸盐
没食子酸表没食子酸酯
色谱法
生物化学
抗氧化能力
DPPH
作者
Amanda Stewart,William Mullen,Alan Crozier
标识
DOI:10.1002/mnfr.200400064
摘要
Teas represent a rich source of dietary antioxidants. This paper describes analysis of the antioxidant potential of individual tea phenolics using an on-line high-performance liquid chromatography (HPLC) method. Tea phenolics from Kenyan green and black teas were identified using liquid chromatography – mass spectrometry (LC-MSn) in conjunction with the analysis of their 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS+) radical scavenging ability. Antioxidant potential of flavan-3-ols, caffeoylquinic acids, flavonols, and theaflavins was assessed in comparison to the synthetic vitamin E analogue Trolox. (–)-Epigallocatechin gallate was identified as the most potent antioxidant with a Trolox equivalent antioxidant capacity (TEAC) value of 3.0, contributing approximately 30% of the total antioxidant capacity of green tea. Theaflavins retained antioxidant capacity similar to that of (–)-epicatechin monomers whilst conjugated flavonols did not contribute significantly to the antioxidant capacity of either green or black tea. After HPLC analysis of the antioxidant capacity of phenolics in black tea some 80% of antioxidant activity remained unaccounted for indicating the potential importance of thearubigens as antioxidants in black teas.
科研通智能强力驱动
Strongly Powered by AbleSci AI