体外模拟胃肠消化中山楂多酚及抗氧化活性的变化

本实验研究了山楂多酚、黄酮及抗氧化活性在体外模拟胃肠道环境下的变化规律，并利用高效液相色谱法测定了胃肠消化对山楂中5 种主要单体酚类化合物的影响。结果表明：山楂多酚在模拟胃液消化中稳定性较好，总多酚、黄酮含量及抗氧化能力均无显著性变化（P＞0.05）；而在模拟肠液消化中山楂多酚易发生降解，总多酚、黄酮含量在0.5 h内分别降低16.26%和7.46%，抗氧化能力也随之降低10.25%。高效液相色谱测定结果显示，5 种单体酚类化合物含量在胃液消化中无显著性变化（P＞0.05）；而在肠液消化中变化情况不相一致，其中金丝桃苷和异槲皮苷含量无显著性变化（P＞0.05），表儿茶素在0.5 h内完全降解，绿原酸和原花青素B2在0.5 h内分别显著下降40.78%和28.99%（P＜0.05）。

Changes in Polyphenol Contents and Antioxidant Activity in Hawthorn (Crataegus pinnatifida Bunge) during Simulated Gastrointestinal Digestion

This study was aimed to investigate the changes in the total polyphenol and flavonoid contents and antioxidant activity of hawthorn during simulated gastrointestinal digestion. The effect of simulated gastrointestinal digestion on 5 main phenolic compounds was also determined using high performance liquid chromatography (HPLC). The results showed that hawthorn polyphenols were stable to gastric digestion; the contents of total polyphenols and flavonoids and antioxidant activity showed no significant changes during gastric digestion (P > 0.05). However, hawthorn polyphenols were easily degraded during intestinal digestion and the contents of total polyphenols and flavonoids and antioxidant activity decreased by 16.26%, 7.46% and 10.25% after 0.5 h, respectively. Furthermore, HPLC results indicated that 5 phenolic compounds revealed no remarkable changes during gastric digestion (P > 0.05), whereas the changes during intestinal digestion were not consistent. During intestinal digestion, hypericin and isoquercitrin did not change noticeably (P > 0.05), while epicatechin was completely degraded after 0.5 h. Moreover, the contents of chlorogenic acid and procyanidin B2 decreased by 40.78% and 28.99% after 0.5 h (P < 0.05).