岩藻糖基化胞外多糖降解产物对婴儿肠道菌群的影响

Effects of Degradation Products of Fucosylated Exopolysaccharide on Infant Gut Microflora

通过体外模拟发酵体系评价岩藻糖基化胞外多糖降解产物(degradation products of fucosylated exopolysaccharide,DFcP)对婴儿粪便来源菌群的调控作用。单菌培养结果表明DFcP能够被婴儿双歧杆菌(Bifidobacterium longum subsp.infantis ATCC 15697)、短双歧杆菌(B.breve ATCC 15700)和植物乳杆菌(Lactobacillus plantarum CGMCC 1.19)选择性利用,并促进短链脂肪酸(short chain fatty acids,SCFAs)的积累。婴儿粪便菌群体外模拟发酵实验表明,与2’-岩藻糖基乳糖相比,DFcP能够更快地被粪便菌群利用,产生更高水平的SCFAs(34.57 mmol/L,P<0.05)。单分子实时测序结果表明,DFcP提高了菌群厚壁菌门(Firmicutes)的占比,上调肠球菌属(Enterococcus)、乳杆菌属(Lactobacillus)和双歧杆菌属(Bifidobacterium)的相对丰度,并进一步通过实时聚合酶链式反应进行验证。综上,DFcP能够被婴儿粪便菌群快速利用,显著调节菌群结构并促进有益代谢产物SCFAs的积累。本研究证实DFcP作为新型益生元的潜力,为进一步开发新型岩藻糖基寡糖资源提供了理论基础。

The effects of the degradation products of fucosylated exopolysaccharide(DFcP)on the infant fecal microflora were evaluated in vitro in this study.The results of single-strain culture showed that DFcP was selectively utilized by Bifidobacterium longum subsp.infantis ATCC 15697,B.breve ATCC 15700 and Lactobacillus plantarum CGMCC 1.19,and promoted the accumulation of short chain fatty acids(SCFAs).Compared with 2’-fucosylactose(2’-FL),DFcP was utilized more quickly by the fecal microbiota and led to higher levels of SCFA production(34.57 mmol/L,P<0.05)during in vitro fermentation.The results of single-molecule real-time sequencing(SMRT)showed that DFcP increased the proportion of Firmicutes in the fecal microbiota,up-regulated the relative abundance of Enterococcus,Lactobacillus and Bifidobacterium,which was verified by the results of real-time polymerase chain reaction(PCR).In conclusion,DFcP could be rapidly utilized by the infant fecal microbiota,and significantly regulate its structure and promote the accumulation of the beneficial metabolite SCFAs.This study reveals the potential of DFcP as new prebiotics,which provides a theoretical basis for further development of novel fucosylated oligosaccharide resources.