Fig. 3

Heat map representation of the identified 48 bacterial taxa and their relation to the identified betaine compounds and the diets. Left: correlations between the relative abundance of microbial taxa in the caecal contents of mice and betaine compounds in the caecal tissue (Pearson correlation, p < 0.05 marked with a circle) in HF and bran-enriched diet groups. Centre: comparison of all diet groups (Kruskal–Wallis one-way ANOVA, p < 0.05 marked with a circle) and fold changes of the relative abundances of microbial taxa between the bran-enriched treatment diets and the control diets, between the rye bran and wheat aleurone-enriched diets, and between the diets containing unprocessed and bioprocessed rye bran or wheat aleurone (Mann–Whitney U test, p < 0.05 marked with a circle). Right: normalized average bacterial abundances in each diet group