番石榴结合态多酚对小鼠肠道菌群结构及多样性的影响研究

为探究番石榴结合态多酚对小鼠肠道菌群的影响,本试验将CD-1小鼠分为空白组、高浓度组(500 mg·kg^-1)和低浓度组(100 mg·kg^-1)3组,在灌胃5周后,收集小鼠的无菌粪便,扩增肠道菌群16S rRNA基因高变域V3-V4,通过16S rRNA基因扩增子测序技术检测小鼠肠道菌群的α多样性、β多样性,以及门、属水平的物种组成。结果表明,与空白组相比,低浓度组中菌群的均匀性和丰富度显著提高(P<0.05);基于门水平分析,厚壁菌门、拟杆菌门和疣微菌门3个菌门的相对丰度值较大;在属水平中,高低浓度组均能降低拟杆菌属相对丰度,低浓度组能提高乳杆菌相对丰度,并且高浓度组中艾克曼菌属的相对丰度大幅提高。综上所述,番石榴结合态多酚能提高小鼠肠道菌群的均匀性和丰富度,且对菌群结构具有调节作用,既能提高益生菌的相对丰度,也能降低有害菌的相对丰度。本研究结果可为番石榴结合态多酚的活性研究和实际应用提供理论参考。

Effect of Bound Polyphenols in Psidium Guajava on Mice Intestinal Flora Structure and Diversity

In order to explore the effects of bound polyphenols in Psidium guajava on fut microbiota in mice, CD-1 mice were divided into three groups, the blank group, the high concentration group (500 mg·kg ^-1) and the low concentration group (100 mg·kg^-1). At the end of the fifth week of gavage, the gene hypervariable V3-V4 of 16S rRNA in the gut microbiota was amplified after sterile feces collection. The alpha and beta-diversity, the species composition of the gut microbiota at the phylum and genus levels were detected by 16S rRNA gene amplicon sequencing technology. The results showed that compared to the blank group, the microbial diversity and richness in low concentration group were improved significantly (P<0.05). Bacteroides, Firmicutes, and Verrucomicrobia were the dominated gut microbiota in mice at the phylum level. At the genus level, both high and low concentrations groups could decrease the relative abundance of Bacteroides. Low concentration group could enhance the abundance of Lactobacillus, and a substantial increase of the proportion of Akkermansia was observed in high concentration group. In summary, bound polyphenols in Psidium guajava could increase diversity and richness of gut microbiota in mice, which could improve the relative abundance of probiotics, while decrease that of harmful bacteria. The results of this study would provide theoretical reference for the activity research and practical application of bound polyphenols in Psidium guajava.