Bacillus licheniformis promotes the enrichment of Prevotella and relieve coliti.

Although Bacillus licheniformis (B. licheniformis), as a well-established probiotic preparation, has been demonstrated to alleviate ulcerative colitis (UC), the precise mechanisms by which it modulates inflammation and the gut microbiome remain unclear. Here, we investigate the role of B. licheniformis in ameliorating colitis by modulating key bacterial species and metabolites, which is supported by multi-level experimental framework encompassing in vivo and in vitro functional validation, fecal microbiota transplantation models, and clinical intervention trials, while also revealing cross-feeding interactions among bacteria.