通过体外模拟胃肠消化法模拟梨（鸭梨、蜜梨和香梨）在胃肠道的消化过程，测定模拟胃肠消化过程中抗氧化活性物质（以多酚表示）和黄酮的释放量及总抗氧化活性的变化规律。结果显示，模拟胃环境消化过程中，与消化0 h相比，鸭梨、蜜梨和香梨的多酚最大释放量是其2.11、1.51、2.24倍，黄酮最大释放量是其1.51、1.92、2.67倍，最大抗氧化活性是其1.79、1.79、3.12倍；模拟肠环境消化过程中，与胃消化0 h和肠消化0 h相比，鸭梨、蜜梨和香梨的多酚最大释放量分别为其1.83、1.99、2.58倍和0.92、1.17、1.18倍，黄酮的最大释放量分别为其0.90、1.21、1.79倍和0.49、0.63、0.63倍，最大抗氧化活性分别为其2.78、2.15、3.42倍和1.34、1.42、1.12倍。这表明，梨在模拟胃肠消化过程中，胃蛋白酶、胰酶及胃酸均可以促进抗氧化活性物质释放，释放的抗氧化活性物质可能来自多酚与蛋白质、多糖、脂质等形成的复合物的水解。

The Changes in release of antioxidant active substances (expressed in polyphenols) and flavonoids, as well as antioxidant activity by oxygen radical absorption capacity (ORAC) of pears (Yali, Mili and Fragrant pear) were determined during in vitro simulated gastrointestinal digestion process. The results showed that the maximum polyphenols release of Yali, Mili and Fragrant pear were 2.11-, 1.51- and 2.24-folder higher than that at timepoint 0 h during the gastric digestion process; the biggest flavonoids release were 1.51, 1.92 and 2.67 times more than that at 0 h as well as the maximum ORAC values raised 1.79, 1.79 and 3.12 times respectivly. In simulated gastric digestion and intestinal digestion, the biggest polyphenols release of Yali, Mili and Fragrant pear were 1.83-, 1.99-, 2.58- and 0.92-, 1.17-, 1.18-folder higher than that at timepoint 0 h (gastric digestion and intestinal digestion separately); the biggest flavonoids release were 0.90, 1.21, 1.79 and 0.49, 0.63, 0.63 times as much as that at 0 h, as well as the maximum ORAC values raised 2.78, 2.15,3.42 and 1.34, 1.42, 1.12 times respectivly. This indicates that pepsin, pancreatin and gastric acid can promote the release of antioxidative substances of pear during simulated gastrointestinal digestion, and the release antioxygen may come from hydrolysis of complexes that polyphenols form with proteins, polysaccharides, lipids, etc.

广东省省国际合作项目（2012B050600031）；深圳市科技计划项目（JCYJ20130331151512026）