Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, Japan.
J Agric Food Chem. 2013 Jan 30;61(4):966-72. doi: 10.1021/jf304105w. Epub 2013 Jan 22.
5-Caffeoylquinic acid (5-CQA) is generally referred to as chlorogenic acid and exhibits various biological activities such as antioxidant activity and porcine pancreas α-amylase inhibitory activities. 5-CQA may be useful as an antioxidant for food and to prevent diabetes and obesity. The degradation of 5-CQA and caffeic acid (CA) in an aqueous solution at 37 °C and pH 5.0-9.0 was studied. The degradation of 5-CQA and CA, demonstrating time and pH dependence (i.e., the rate constant, k, was higher at higher pH), was satisfactorily described by the Weibull equation. The stability of 5-CQA at pH 7.4 and 9.0 was improved by adding (-)-epigallocatechin gallate (EGCG) and ascorbic acid (AA). Moreover, the degradation of 5-CQA in the presence of EGCG or AA could be described by the Weibull equation. The k value in the presence of EGCG or AA was dependent on their concentration.
5-咖啡酰奎宁酸（5-CQA）通常被称为绿原酸，具有抗氧化活性和猪胰腺α-淀粉酶抑制活性等多种生物活性。5-CQA 可用作食品抗氧化剂，以预防糖尿病和肥胖症。在 37°C 和 pH5.0-9.0 的水溶液中研究了 5-CQA 和咖啡酸（CA）的降解。5-CQA 和 CA 的降解具有时间和 pH 依赖性（即，在较高 pH 下，速率常数 k 更高），可以用 Weibull 方程很好地描述。在 pH7.4 和 9.0 时，通过添加（-）-表没食子儿茶素没食子酸酯（EGCG）和抗坏血酸（AA）可以提高 5-CQA 的稳定性。此外，在 EGCG 或 AA 的存在下，5-CQA 的降解可以用 Weibull 方程来描述。在 EGCG 或 AA 存在下的 k 值取决于它们的浓度。
