Fig. 4

Oral EGCG regulated the composition and function of intestinal microbiota. a α-diversity upon oral therapy represented by the Sobs index. b Principal coordinate analysis (PCoA) plots upon oral therapy assessed by PERMANOVA. The relative abundance of fecal bacterial phyla (c); and genera (d) presented in 99.5% of the community upon oral therapy. e Analysis of differences in the microbial taxa shown by LEfSe (linear discriminant analysis (LDA) coupled with effect size measurements) upon oral therapy. Concentrations of fecal acetate (f), propionate (g), and butyrate (h) upon oral therapy. Data were presented as means ± SEM (n = 7–8 per group). Statistical significance was determined using one-way ANOVA, followed by Tukey test. *P ≤ 0.05, **P ≤ 0.01, ***P ≤ 0.001. i Spearman correlation between intestinal microbiota and anti-inflammatory or anti-oxidative parameters in DSS-treated mice in response to oral EGCG. The red color denotes a positive correlation, while blue color denotes a negative correlation. The intensity of the color is proportional to the strength of Spearman correlation. *P ≤ 0.05, ***P ≤ 0.001