Comparison of Different Soluble Dietary Fibers during the In Vitro Fermentation Process

Soluble dietary fibers being fermented by gut microbiota constitute a pivotal prerequisite for soluble dietary fibers exhibiting physiological functions. However, the relationship between fiber type and gut microbiota metabolism remains unclear. The purpose of this study was to investigate and compare the effect of fiber types on short-chain fatty acid (SCFA) biosynthesis in a simulated colon. Results showed that different soluble dietary fibers caused distinct metabolic profiles both in SCFAs and organic acids. Further analysis revealed that the SCFA biosynthesis pathway was related to the chain structure of fiber polysaccharides. Moreover, the microbial community structure showed substantial difference among experimental groups. Parabacteroides was substantially elevated in the resistant starch group, while Lactobacillus was the predominant genus in other groups. Correlation analysis further revealed that SCFA biosynthesis was correlated with microbial taxa at different taxonomic levels. Totally, the present study provided an insight into targeted intervention of gut microorganisms for dictating SCFA and organic acid production.