Modulation of human gut microbiota composition and metabolites by arabinogalactan and Bifidobacterium longum subsp. longum BB536 in the Simulator of the Human Intestinal Microbial Ecosystem (SHIME®)

[Display omitted] •Arabinogalactan (AG) gave higher amounts of SCFA, A. muciniphila and F. prausnitzii than starch.•The SCFA changes induced by the AG/B. longum combination continued after B. longum supplementation.•The AG/B. longum combination increased AG degradation, butyrate and F. prausnitzii.•The effect of the AG/B. longum combination was dependent on the colon region. The Mucosal-Simulator of the Human Intestinal Microbial Ecosystem (SHIME) was used to differentiate the gut microbial fermentation of arabinogalactan (AG) and starch before (T1), during (T2), and after (T3) one-week Bifidobacterium longum subsp. longum BB536 supplementation. Adding 10 g/L of either AG or starch to the basal medium (T1) promoted short-chain fatty acid (SCFA) production in three successive SHIME colon vessels. AG fermentation (T1) resulted in higher total SCFAs (P