食物基质对模拟消化茶多酚含量及抗氧化活性的影响

采用模拟胃肠消化模型研究食物基质对茶多酚含量及抗氧化活性的影响。结果表明:与茶多酚模拟胃消化比较,添加牛奶、糊化淀粉和食用油后,茶多酚含量分别降低21.7%、15.0%和3.3%,白砂糖或柠檬酸的添加对其含量无明显影响。添加柠檬酸后,茶多酚清除DPPH自由基(DPPH·)能力显著增强,清除ABTS自由基(ABTS+·)能力显著降低,总抗氧化能力无明显变化;添加白砂糖后其清除ABTS+·能力显著降低,其他抗氧化活性无明显变化;添加糊化淀粉或牛奶后,其抗氧化活性显著降低;添加食用油后其抗氧化活性无明显变化。与茶多酚模拟肠消化比较:添加牛奶后茶多酚含量显著降低7.7%,其他食物基质的添加则对其含量无明显影响。添加柠檬酸后,茶多酚的总抗氧化能力与清除ABTS+·能力显著增强,清除DPPH·能力无明显变化;添加食用油后其清除DPPH·和ABTS+·能力显著增强,总抗氧化能力无明显变化;添加糊化淀粉或牛奶后,其清除ABTS+·能力显著增强,其他则无明显变化;添加白砂糖后其抗氧化活性无明显变化。

Effects of food matrix on content and antioxidant activity of tea polyphenols during simulated gastrointestinal digestion

Simulated gastric intestinal digestion model was used to evaluate effects of food matrixes on the contents and antioxidant activities of tea polyphenols in vitro.Results showed that adding milk,gelatinized starch and soybean oil significantly decreased content of tea polyphenols by 21.7％,15.0％ and 3.3％,respectively.Comparing tea polyphenols after simulated gastric digestion,adding sucrose or citric acid had no influence on its content.DPPH · radical scavenging capacity of tea polyphenols significantly increased and ABTS+ · radical scavenging capacity significantly decreased after adding citric acid,with no changes of the total antioxidant capacity.ABTS+ · radical scavenging capacity of tea polyphenols significantly decreased after adding sucrose.Other antioxidant activities had no changes.The antioxidant activities of tea polyphenols were significantly reduced after adding gelatinized starch or milk.Soybean oil had no influences on its antioxidant activities.Comparing with tea polyphenols after simulated gastrointestinal digestion,adding milk significantly decreased contents of tea polyphenols by 7.7％ and adding others had no influence.The total antioxidant capacity and ABTS+ · radical scavenging capacity of tea polyphenols significantly increased after adding citric acid.DPPH · radical scavenging capacity had no change.DPPH · and ABTS+ · radical scavenging capacity of tea polyphenols significantly increased after adding soybean oil,with total antioxidant capacity of no change.ABTS+ · radical scavenging capacity of tea polyphenols significantly increased after adding gelatinized starch or milk,with other antioxidant activities of no changes.The antioxidant activities of tea polyphenols had no changes after adding sucrose.