基于体外发酵研究膳食纤维复合体对老年人肠道菌群的调节作用

Study on the Regulation of Gut Microbiota in the Elderly by Dietary Fiber Complex Based on in Vitro Fermentation

该研究旨在探究膳食纤维复合体(Dietary Fiber Complex,DFC)对代表性人体肠道菌群及其代谢物的调节。采集10位65~75岁老年人的粪便,分性别开展DFC干预的体外发酵实验。结果发现,2%添加量的DFC组干预效果最好,其中女性组大肠杆菌属、拟杆菌属、双歧杆菌属、乳酸杆菌属的相对表达量为对照组的52.76%、43.40%、249.79%和232.99%,男性组大肠杆菌属、拟杆菌属、双歧杆菌属和乳酸杆菌属的相对表达量为对照组的44.02%、53.14%、228.71%和206.11%。显著差异的肠道菌群代谢物中,女性组的异丁酸、丙酸、甲酸相对丰度显著增加(P<0.01),蛋氨酸、组氨酸、β-葡萄糖、苯丙氨酸、苏氨酸、丙三醇、天冬氨酸、精氨酸、1-甲基组氨酸的相对丰度显著减少(P<0.01),男性组的异丁酸、丙酸、丁酸盐、甲酸相对丰度显著增加(P<0.01),组氨酸、β-葡萄糖、苯丙氨酸、苏氨酸和天冬氨酸相对丰度显著减少(P<0.01),二者潜在的代谢途径都为组氨酸代谢与苯丙氨酸、酪氨酸和色氨酸生物合成。研究结果表明DFC对人体肠道菌群及代谢物的调节作用明显,且在不同性别上潜在的代谢途径变化一致。

The regulatory effect of dietary fiber complex(DFC)on the representative human gut microbiota and derived metabolites was explored.Faeces of 10 elderly people aged 65~75 years were collected,and in vitro fermentation of the DFC for intervention was performed according to gender.It was found that the intervention effect of the 2%DFC addition was the best,and the relative expressions of Escherichiacoil,Bacteroides,Bifidobacterium and Lactobacillus for the female group were 52.76%,43.40%,249.79%and 232.99%,respectively,of those in the control group.The relative expressions of of Escherichiacoil,Bacteroides,Bifidobacterium and Lactobacillus for the male group were 44.02%,53.14%,228.71%and 206.11%,respectively,of those in the control group.Among the significantly different gut flora metabolites,the relative abundances of isobutyrate,propionate and formic acid increased significantly(P<0.01),whilst the relative abundance of methionine,histidine,β-glucose,phenylalanine,threonine,alanine,aspartate,arginine and 1-methylhistidine decreased significantly(P<0.01)in the female group.In the male group,the relative abundance of isobutyrate,propionate,butyrate and formic acid increased significantly(P<0.01),whilst the relative abundance of histidine,β-glucose,phenylalanine,threonine and aspartate decreased significantly(P<0.01).The underlying metabolic pathways for both groups were histidine metabolism,and phenylalanine,tyrosine and tryptophan biosynthesis.The research results showed that DFC has a significant regulatory effect on human gut microbiota and derived metabolites,and the changes in the potential metabolic pathways are consistent across genders.