Effects of calcium supplementation on the composition and activity of in vitro simulated gut microbiome during inulin fermentation

abundance remained over 1% regardless of colonic pH gradient, calcium source, or fermentation time. In addition, short-chain fatty acid (SCFA) production was dependent on the calcium source. For instance, compared to the control group, the CaCi group exhibited higher acetate production at low and high colonic pH gradients, while the CaPi and CaCa groups showed enhanced lactate production at medium and low pH gradients. These findings can increase our understanding of the impacts of calcium-rich diets on the human gut microbiome and its metabolic activity.