Department of Biological and Chemical Engineering, Aarhus University, Aarhus, Denmark.
Department of Food Science, Aarhus University, Aarhus, Denmark.
Gut Microbes. 2023 Jan-Dec;15(1):2241209. doi: 10.1080/19490976.2023.2241209.
Previous studies indicated an intrinsic relationship between infant diet, intestinal microbiota composition and fermentation activity with a strong focus on the role of breastfeeding on microbiota composition. Yet, microbially formed short-chain fatty acids acetate, propionate and butyrate and other fermentation metabolites such as lactate not only act as substrate for bacterial cross-feeding and as mediators in microbe-host interactions but also confer antimicrobial activity, which has received considerably less attention in the past research. It was the aim of this study to investigate the nutritional-microbial interactions that contribute to the development of infant gut microbiota with a focus on human milk oligosaccharide (HMO) fermentation. Infant fecal microbiota composition, fermentation metabolites and milk composition were analyzed from 69 mother-infant pairs of the Swiss birth cohort Childhood AlleRgy nutrition and Environment (CARE) at three time points depending on breastfeeding status defined at the age of 4 months, using quantitative microbiota profiling, HPLC-RI and H-NMR. We conducted fermentations in the presence of HMO fermentation metabolites and determined the antimicrobial activity of lactate and acetate against major and representatives. Our data show that fucosyllactose represented 90% of the HMOs present in breast milk at 1- and 3-months post-partum with fecal accumulation of fucose, 1,2-propanediol and lactate indicating fermentation of HMOs that is likely driven by . Concurrently, there was a significantly lower absolute abundance of in feces of exclusively breastfed infants at 3 months. , lactate inhibited strains of . Taken together, this study not only identified breastfeeding dependent fecal microbiota and metabolite profiles but suggests that HMO-derived fermentation metabolites might exert an inhibitory effect against selected gut microbes.
先前的研究表明，婴儿饮食、肠道微生物群落组成和发酵活动之间存在内在关系，其中母乳喂养对微生物群落组成的影响受到了广泛关注。然而，微生物形成的短链脂肪酸（如乙酸盐、丙酸盐和丁酸盐）和其他发酵代谢产物（如乳酸）不仅作为细菌互养的底物和微生物-宿主相互作用的介质发挥作用，而且还具有抗菌活性，但在过去的研究中，这方面的研究相对较少。本研究旨在探讨促进婴儿肠道微生物群落发展的营养-微生物相互作用，重点关注人乳寡糖（HMO）发酵。通过定量微生物分析、高效液相色谱-折射率（HPLC-RI）和核磁共振（H-NMR）技术，在婴儿 4 个月大时根据母乳喂养状态对 69 对瑞士出生队列“儿童过敏营养与环境（CARE）”的母婴进行了三次分析，检测了婴儿粪便微生物群落组成、发酵代谢产物和乳汁成分。我们在 HMO 发酵代谢产物存在的情况下进行了发酵实验，并测定了乳酸盐和乙酸盐对主要革兰氏阳性菌和革兰氏阴性菌的抗菌活性。我们的数据表明，岩藻糖基乳糖在产后 1 个月和 3 个月时分别占母乳中 HMO 的 90%，粪便中存在岩藻糖、1,2-丙二醇和乳酸盐，表明 HMO 可能是由 发酵的。同时，纯母乳喂养婴儿粪便中 3 个月时的绝对丰度明显较低。此外，乳酸盐抑制了 的生长。综上所述，本研究不仅确定了依赖母乳喂养的粪便微生物群和代谢物特征，而且表明 HMO 衍生的发酵代谢产物可能对选定的肠道微生物发挥抑制作用。
