茶多酚在模拟胃肠消化过程中含量及活性的变化规律

通过模拟消化模型分析茶多酚在胃肠消化过程中成分和抗氧化活性的变化规律,及其对肠道细菌生长的影响。结果表明,与胃部相比,茶多酚在肠部降解能力更为显著;经过模拟胃消化,茶多酚含量降低了12.00%,GCG显著降低了32.50%,EGC增加了13.80%;模拟肠消化后,茶多酚含量大幅度地降低了35.90%～46.10%,EGCG显著降低了98.40%～98.70%,GC则显著增加了97.00%～114.00%;模拟胃肠消化后,茶多酚的总抗氧化能力、DPPH·和ABTS~+·的清除能力均大幅度降低(p0.05),除肠消化阶段清除ABTS~+·的能力外,其余消化阶段的抗氧化能力均与茶多酚含量呈正相关;此外,研究模拟消化前后茶多酚对肠道细菌生长的影响,发现消化前其具有显著抑制大肠杆菌和增殖嗜酸乳杆菌生长的作用,模拟胃肠消化后,茶多酚对大肠杆菌抑菌效果增强,但对嗜酸乳杆菌无显著作用。

Changes in Content and Antioxidant Activity of Tea Polyphenols during in Vitro Simulated Gastrointestinal Digestion

The composition and antioxidant activity of tea polyphenols in vitro were evaluated using gastric intestinal digestion model. Their effect on the growth of intestinal bacteria was also investigated. Results showed that the degradability of tea polyphenols in simulated gastrointestinal digestion was more significant than that of after simulated gastric digestion. During the simulated gastric digestion, the content of tea polyphenols decreased by 12.00%, GCG decreased significantly by 32.50%, EGC increased by 13.80%. During the simulated gastrointestinal digestion, the content of tea polyphenols decreased significantly by 35.90%~46.10%, EGCG decreased significantly by 98.40%~98.70%, GC increased significantly by 97.00%~114.00%. The total antioxidant capacity, DPPH? radical scavenging capacity and ABTS+? radical scavenging capacity of tea polyphenols were significantly decreased after simulated gastrointestinal digestion (p<0.05). During the simulated gastrointestinal digestion, the antioxidant capacity was positively correlated with the content of tea polyphenols, except ABTS+? radical scavenging capacity. Effect of tea polyphenols on intestinal bacterial growth during the simulated gastrointestinal digestion was evaluated. Results showed that tea polyphenols significantly inhibited the growth of Escherichia coli and proliferated the growth of Lactobacillus acidophilus. After simulated gastrointestinal digestion, bacteriostatic effect of tea polyphenols on Escherichia coli enhanced, but had no significant effect on Lactobacillus acidophilus.