Fig. 5. Administration of B. wexlerae altered the intestinal environment, including gut bacterial composition and fecal short-chain fatty acid (SCFA) content, in mice.

A Raman spectroscopic analysis. Raman shift signals specific for protein and starch were plotted on bacterial cells of B. wexlerae (Bw) and major intestinal bacteria including Bacteroide vulgatus (Bv), Prevotella copri (Pc), and Faecalibacterium prausnitzii (Fp). a.u., arbitrary units. B Starch (amylose and amylopectin) contents in B. wexlerae (Bw) and major intestinal bacteria, including B. vulgatus (Bv), P. copri (Pc), and F. prausnitzii (Fp). Data are representative of two independent experiments (n = 4 biologically independent samples, mean ± 1 SD). C The concentrations of succinate, lactate, acetate, propionate, propionate, and butyrate in fresh medium (none) and B. wexlerae culture supernatant (Bw). Data are representative of two independent experiments (n = 4, mean ± 1 SD). * P = 0.0286 (two-tailed Mann–Whitney U test). D SCFA content in fecal samples from mice. Mice were maintained on CD or HFD for 8 weeks with or without oral administration of B. wexlerae three times each week, after which fecal SCFAs were measured by HPLC. Data are combined from three independent experiments (n = 15, mean ± 1 SD). *P < 0.05 (one-way ANOVA). E Principal coordinate analysis (PCoA) of fecal bacterial composition in mice according to the Bray–Curtis distance at genus level. Mice were maintained on CD or HFD for 8 weeks with or without oral administration of B. wexlerae three times each week, after which fecal bacterial composition was analyzed by 16S amplicon sequencing. Data are combined from two independent experiments (n = 10). (F) Differences in bacterial taxonomy were ranked according to the linear discriminant analysis (LDA) effect size between HFD-fed mice and HFD-fed mice supplemented with B. wexlerae. CD, CD-fed mice; HFD, HFD-fed mice, HFD + Bw, HFD-fed mice supplemented with B. wexlerae.