Rachmühl Carole, Lacroix Christophe, Cabrera Paula Momo, Geirnaert Annelies
ETH Zurich.
Res Sq. 2023 Jul 7:rs.3.rs-3101157. doi: 10.21203/rs.3.rs-3101157/v1.
Appropriate models to investigate the impact of novel nutritional strategies on the gut microbiota of infants living in rural Africa are scarce. Here, we aimed to develop such a continuous gut fermentation model based on the PolyFermS platform. Eight immobilized Kenyan infant fecal microbiota were used as inoculum for continuous PolyFermS colon models fed with medium mimicking the weaning infant diet. Fructo-oligosaccharides (FOS) supplementation (1, 4 and 8 g/L) and cultivation pH (5.8 and 6.3) were stepwise investigated. Conditions providing a close match between fecal and microbiota (pH 5.8 with 1 g/L FOS) were selected for investigating long-term stability of four Kenyan infant PolyFermS microbiota. The shared fraction of top bacterial genera between fecal and microbiota was high (74-89%) and stable during 107 days of continuous cultivation. Community diversity was maintained, and two distinct fermentation metabolite profiles, propiogenic and butyrogenic, of infant fecal microbiota established from day 8 onwards and stayed stable. We present here the first rationally designed and accurate continuous cultivation model of African infant gut microbiota. This model will be important to assess the effect of dietary or environmental factors on the gut microbiota of African infants with high enteropathogen exposure.
用于研究新型营养策略对生活在非洲农村地区婴儿肠道微生物群影响的合适模型很少。在此，我们旨在基于PolyFermS平台开发这样一种连续肠道发酵模型。使用8种固定化的肯尼亚婴儿粪便微生物群作为接种物，接种到以模拟断奶婴儿饮食的培养基喂养的连续PolyFermS结肠模型中。逐步研究了低聚果糖（FOS）添加量（1、4和8 g/L）和培养pH值（5.8和6.3）。选择粪便和微生物群之间匹配度高的条件（pH 5.8，FOS添加量1 g/L）来研究4个肯尼亚婴儿PolyFermS微生物群的长期稳定性。粪便和微生物群中顶级细菌属的共享比例很高（74 - 89%），并且在连续培养107天期间保持稳定。群落多样性得以维持，从第8天开始建立了婴儿粪便微生物群的两种不同发酵代谢物谱，即产丙酸型和产丁酸型，并且保持稳定。我们在此展示了首个合理设计且准确的非洲婴儿肠道微生物群连续培养模型。该模型对于评估饮食或环境因素对高肠道病原体暴露的非洲婴儿肠道微生物群的影响具有重要意义。
