AS TFTAK, Mäealuse 2/4B, 12618, Tallinn, Estonia.
School of Natural Sciences and Health, Tallinn University, Narva mnt 25, 10120, Tallinn, Estonia.
Sci Rep. 2024 Sep 27;14(1):22208. doi: 10.1038/s41598-024-72673-9.
This study focuses on the resilience of gut microbiota during a five-month multi-interventional nutrition trial. The modulatory effects of beta-glucan, rye bran and two dietary fiber mixtures on the fecal pH and compositional changes of the microbiome of healthy subjects were studied. To analyze the stability of intestinal microbiota, we collected an extensive dataset of sequential fecal samples (23-29 from each participant) during a week of the base, beta-glucan consumption and wash-out periods accompanied by the collection of daily food diary data. Microbiota analyses were also conducted after the end of each fiber intake and wash-out period, along with measurements of fecal organic acids and pH. Based on the dominant bacterial taxa, two prevalent microbiota types were identified. The Prevotella-type microbiota responded more to the tested dietary fibers, while the Bacteroides-type microbiota was the least affected. Three microbiota types could not be clustered and behaved differently. Although we noted individual effects of definite fibers on participants' gut microbiota and metabolic profile, relative abundances of bacteria remained stable in the base period (z-scores - 2.2 to 2.3). In most cases, the bacterial abundances of the final samples remained within the normal fluctuation range stressing out the resilience of healthy microbiota. The pH of all fecal samples varied between 6.1 and 8.3 and was associated with the concentration of organic acids and microbial composition. The effect of dietary fibers on the metabolism of fecal microbiota clearly depended on the individual microbiota type. Combining the analysis of gut microbiota with knowledge of the properties of dietary fibers would provide a powerful strategy for nutrition guidance and disease prevention.
本研究关注的是在为期五个月的多干预营养试验中肠道微生物组的弹性。研究了β-葡聚糖、黑麦麸和两种膳食纤维混合物对健康受试者粪便 pH 值和微生物组组成变化的调节作用。为了分析肠道微生物组的稳定性，我们在基础期、β-葡聚糖消耗期和冲洗期的一周内收集了大量连续粪便样本（每个参与者 23-29 个），同时收集了每日食物日记数据。在每次纤维摄入和冲洗期结束后，还进行了微生物组分析，并测量了粪便有机酸和 pH 值。基于优势细菌分类群，确定了两种常见的微生物组类型。Prevotella 型微生物组对测试的膳食纤维反应更敏感，而 Bacteroides 型微生物组受影响最小。三种微生物组类型无法聚类，表现不同。尽管我们注意到某些纤维对参与者肠道微生物组和代谢特征的个体影响，但基础期相对细菌丰度仍保持稳定（z 分数为-2.2 至 2.3）。在大多数情况下，最终样本的细菌丰度仍在正常波动范围内，这强调了健康微生物组的弹性。所有粪便样本的 pH 值在 6.1 到 8.3 之间变化，与有机酸浓度和微生物组成有关。膳食纤维对粪便微生物组代谢的影响显然取决于个体微生物组类型。将肠道微生物组分析与膳食纤维特性的知识相结合，将为营养指导和疾病预防提供有力策略。
