Unveiling the microbiome-mediated potential of a carob-based formulation (Csat®): human fecal fermentation, SCFA production, and potential connections with satiety pathways

Microbial fermentation of dietary fibers produces short-chain fatty acids (SCFAs) that may shape host metabolism and appetite control. Csat®, a standardized carob extract, has shown satiety and metabolic benefits in animal models, but its influence on human gut microbiome remained untested. We therefore incubated human fecal microbiota in anaerobic batch fermentations with Csat®, a seed-derived galactomannan fraction (GM), a carob pulp extract (CPE), or control medium, and profiled bacterial community composition (sequencing of full-length 16S rRNA gene amplicons), predicted functional capacity (PICRUSt2/COG, CAZy), and SCFA output (GC-FID) at 0, 24 and 48 hours. Csat® produced the most pronounced fermentation response: across timepoints it generated the highest acetate, propionate and butyrate concentrations while preserving bacterial community balance. Taxonomically, Csat® shifted the microbiota toward carbohydrate-degrading taxa (notably Bacteroides ) and canonical butyrogenic genera ( Anaerostipes and Blautia ), and correlation networks pointed to active cross-feeding between primary degraders and secondary fermenters. Functional inferences mirrored these changes: GM elicited strong extracellular glycosidase signatures consistent with mannan hydrolysis, CPE favored pectin/fructan-targeting functions, and Csat® combined hydrolytic and enhanced sugar-uptake potential (transport ATPases), a combination that plausibly sustains higher SCFA flux. Together, these results show that Csat® can reprogram human-derived microbial communities in vitro to favour SCFA production via complementary hydrolysis and transport processes. The data provide a potential mechanistic bridge between prior in vivo efficacy and the rationale for further clinical studies to test whether microbiome-mediated SCFA increases translate into meaningful hormonal and appetite outcomes in humans.