Tab 1) The gut microbial composition of C57BL/6J mice fed with diets enriched with rye bran and wheat aleurone, analyzed with 16S rRNA sequencing. Tab 2) Betaine levels in the colon contents of C57BL/6J mice fed with diets enriched with rye bran and wheat aleurone; Tab 3) betaine levels in the caecal tissue of C57BL/6J mice fed with diets enriched with rye bran and wheat aleurone; Tab 4) betaine levels in tissues of murine pathogen free (MPF) and germ-free (GF) C57BL/6NTac mice on a basal diet; Tab 5) betaine levels in the in vitro model of the human gut; Tab 6) betaine levels in cereal samples; all betaine levels analyzed with UPLC–QTOF-MS