模拟消化中藜麦的酚类化合物释放和抗氧化活性

Phenolic Compounds Release and Antioxidant Activity of Quinoa(Chenopodium quinoa Willd.)During Simulated Digestion

为了解藜麦(Chenopodium quinoa Willd.)功能性营养成分在人体消化系统的利用效率,以籽粒颜色白、红和黑的3种颜色藜麦为实验材料,采用模拟消化模型分析了藜麦经模拟口腔、胃和肠消化时酚酸、多酚和黄酮释放量、生物可及性及抗氧化活性.结果表明:模拟消化过程中,3种颜色藜麦的酚酸、多酚和黄酮的释放量随消化进程的进行而增加,其中酚酸和黄酮在肠消化阶段释放较多,多酚在胃消化阶段释放较多,红藜麦和黑藜麦的酚类化合物释放量多于白藜麦(P<0.05);模拟消化结束时的酚酸、多酚和黄酮释放量在白藜麦、红藜麦和黑藜麦之间也差异显著(P<0.05),依次分别为34.39、41.73、51.88 mg/(100 g),362.19、400.40、436.62 mg(GAE)/(100 g),28.73、48.90、41.24 mg(RE)/(100 g);模拟消化结束时的生物可及性,酚酸为白藜麦90.33%、红藜麦85.41%和黑藜麦91.61%,多酚为白藜麦81.44%、红藜麦84.09%和黑藜麦78.75%,黄酮为3种颜色藜麦无显著差异约20%(P>0.05);模拟消化过程中,3种颜色藜麦的抗氧化活性(ABTS和DPPH自由基清除能力)也随消化进程的进行而增大,多酚释放量与抗氧化活性呈正相关(P<0.01),红藜麦和黑藜麦的抗氧化活性大于白藜麦(P<0.05).从这些结果可以推论,食用藜麦可以获取酚类化合物功能性营养成分和抗氧化生物活性,食用红藜麦和黑藜麦会获取较白藜麦更多的酚类化合物功能性营养成分和更大的抗氧化生物活性.

In order to understand how functional nutrients from the seeds of the herbaceous plant,quinoa(Chenopodium quinoa Willd.)are utilized in the human digestive system,we examined the release of phenolic acids,polyphenols,and flavonoids together with the bioavailability and antioxidant activity of quinoa during simulated oral,gastrointestinal,and intestinal digestion.White,red,and black varieties of quinoa were used in these experiments.Our results revealed that the release of phenolic acids,polyphenols,and flavonoids from all three varieties of quinoa increases as digestion progresses.Phenolic acids and flavonoids were mainly released during intestinal digestion,while polyphenols were primarily released during gastric digestion.Red and black quinoa varieties released more phenolic compounds as compared to the white quinoa variety(P<0.05).At the completion of simulated digestion,the net release of phenolic acids,polyphenols,and flavonoids was significantly different when comparing results among white,red,and black quinoa(P<0.05),and these values are 34.39,41.73,and 51.88 mg/(100 g);362.19,400.40,and436.62 mg(GAE)/(100 g);and 28.73,48.90,and 41.24 mg(RE)/(100 g)from white,red,and black varieties,respectively.At the completion of simulated digestion,the bioavailability of phenolic acids from white,red,and black quinoa was 90.33%,85.41%,and 91.61%,respectively and the bioavailability of polyphenols was 81.44%,84.09%,and 78.75%,respectively.We detected no significant differences in the bioavailability of flavonoids among the three varieties of quinoa(P>0.05),which were all about 20%.Likewise,the antioxidant activity(the free radical scavenging capacity of ABTS and DPPH)of each of the three varieties of quinoa also increased as digestion progressed;this activity positively correlated with the release of polyphenols(P<0.01).Finally,we found higher levels of antioxidant activity in red and black quinoa compared to that detected in the white variety(P<0.05).Thus,our results suggest that functional nutrients and antioxidant effects are among the benefits obtained from consumption of quinoa.Moreover,when compared to white quinoa,the consumption of red or black varieties may provide relatively higher levels of phenolic compounds and antioxidant effects.