猕猴桃果粉的体外消化、酵解特性及对肠道微生物菌群的影响

Characteristics of in Vitro Digestion and Fermentation of Kiwi Fruit Powder and Its Effects on Intestinal Flora

文章旨在探究猕猴桃果粉的生物活性,为猕猴桃深加工提供更为广阔的前景和方向,加速其产业化发展。利用体外胃肠消化和体外酵解试验,对比不同处理组生物活性物质的变化、对肠道微生物菌群的OTU聚类分析、对门水平和属水平上菌群的相对丰度以及微生物多样性进行分析,对猕猴桃果粉的生物活性和消化酵解特性进行深入研究。结果表明:猕猴桃果粉的总糖和还原糖含量在经过体外胃肠消化吸收后未发生显著变化(P>0.05),经体外酵解后,总糖和还原糖含量显著下降,表明其消化吸收主要发生在体外酵解阶段;总酚的含量在胃肠消化阶段有所增加,在体外酵解阶段无明显变化;猕猴桃果粉能够促进和调节短链脂肪酸的产生,经体外发酵48 h后,猕猴桃果粉组中乙酸含量可达(1.976±0.112)mg/m L发酵液,丙酸含量可达(1.964±0.092)mg/m L发酵液,丁酸含量可达(0.346±0.012)mg/m L发酵液,显著高于空白组和阳性对照组;与空白组相比,猕猴桃果粉组的放线菌门及双歧杆菌属相对丰度上升,分别为34.46%、33.71%;猕猴桃果粉组微生物菌落丰度降低,多样性和均匀度变化并不显著,与空白组群落组成差异较大,说明猕猴桃果粉具有调节肠道微生物组成、维持肠道菌群稳定性的功效,是一种潜在改善人体健康的益生元。研究结果可为明确猕猴桃果粉的生物活性及消化酵解特性提供理论依据。

The biological activity of kiwi fruit powder was explored to provide a broader prospect and direction for the deep processing of kiwi fruit.This study was also aimed to accelerate the industrialization of kiwi fruit powder.In vitro gastrointestinal digestion and in vitro fermentation test were carried out to compared the changes of bioactive substances in different treatment groups.OUT cluster analysis of intestinal microbiota,relative abundance of flora at phyla and genus levels,and microbial diversity analysis were used to study the in vitro digestion and glycolysis characteristics of kiwi fruit powder and its effects on intestinal microflora.The biological activity and digestive and glycolysis characteristics of kiwi fruit powder were conducted an in-depth study.The result showed that the contents of total sugar and reducing sugar of kiwi fruit powder hardly changed after gastrointestinal digestion in vitro,but decreased significantly after fermentation in vitro,which indicated that the digestion and absorption of total sugar and reducing sugar mainly occurred in the stage of fermentation in vitro.The content of total phenol increased in gastrointestinal digestion stage,but did not change significantly in vitro fermentation stage.Kiwi fruit powder promoted and regulated the production of short-chain fatty acids,which had the effect of improving human intestinal health.After 48 h in vitro fermentation,the acetic acid content of kiwi fruit powder group could reach(1.976±0.112)mg/mL,the propionic acid content could reach(1.964±0.092)mg/mL,and the butyric acid content could reach(0.346±0.012)mg/mL,which was significantly higher than that of control check group and positive control group.Compared with control check group,the relative abundance of Actinomycetes and Bifidobacteria in fruit powder group increased,reaching 34.46% and 33.71% respectively.In kiwi fruit powder group,microbial colony abundance decreased,diversity and uniformity did not change significantly,and community composition was significantly different from that in control check group,which indicated kiwi fruit powder had the effect of regulating intestinal microbial composition and maintaining the stability of intestinal flora,which was a potential prebiotic for improving human health.The study provided theoretical basis for clarifying the biological activity and digestive and glycolysis characteristics of kiwi fruit powder.