全麦粉对体外肠道菌群的影响

Effects of Whole Wheat Grain on the Gut Microbiota in Vitro

研究了全麦粉(whole wheat,WW)和精制小麦粉(refined wheat,RW)在体外模拟发酵对肠道微生物的调节作用。实验采用模拟体外消化的方法分别对全麦粉和精制小麦粉进行胃肠道消化,然后利用人体粪便菌群将消化残渣进行发酵并运用新一代16S rRNA测序技术对微生物结构进行分析。结果表明,在成分组成上,全麦粉较精制小麦粉的膳食纤维和多酚等可被微生物发酵利用的成分含量显著增加(p <0.05),分别为精制小麦粉的1.49倍和1.45倍;在肠道微生物组成上,两种小麦粉的发酵均降低了肠道微生物多样性,但显著增加了发酵液中短链脂肪酸的含量(p <0.05),同时调节了肠道菌群的物种组成,拟杆菌门相对丰度下降,厚壁菌门相对丰度升高。与精制小麦粉相比,全麦粉增加了氨基酸球菌属、双歧杆菌属、噬胆菌属、巨单胞菌属、巨型球菌属等的相对丰度,且益生菌-双歧杆菌属相对丰度是精制小麦粉发酵的1.19倍,降低了脱硫弧菌属、小类杆菌属、埃希式菌属、普拉梭菌属、普斯菌属和萨特式菌属等的相对丰度,尤其是致病菌-埃希氏菌属,其相对丰度降低了52%。

The gut microbiota modulation abilities of whole wheat grain (WW) and refined wheat grain (RW) were studied in vitro.In the experiment,the WW and RW were firstly digested in vitro,and then the digesta was fermented by human fecal flora,and the new generation of 16 S rRNA sequencing technology was used to analyzed the microbial structure.Results: Compared with RW,the contents of dietary fiber and phenolic compounds in WW was significantly increased (p < 0.05),and was 1.49 times and 1.45 times of RW,respectively. On the composition of intestinal microbes,fermentation of WW and RW all reduced the diversity of intestinal microorganisms,but significantly increased the contents of short-chain fatty acids in the fermentation broth (p < 0.05),and at the same time regulated the species composition of the intestinal flora,the relative abundance of Bacteroidetes decreased,thick-walled bacteria relative abundance increased. Compared with RW,the WW increased the relative abundance of Aminoococcus,Bifidobacterium,Marchantia,Megaomonas and Megasococcus,and the relative abundance of probiotic-Bifidobacterium was 1.19 times of fermented RW,but decreased the relative abundance of Desulfovibrio,Bacteroides,Echinococcus,Faecalibacterium,Pasteurella and Sutterella,especially pathogenic-Faecalibacterium,and its relative abundance was reduced by52%.