Bacillus coagulans SANK 70258 suppresses Enterobacteriaceae in the microbiota of ulcerative colitis in vitro and enhances butyrogenesis in healthy microbiota.

The aim of this study was to clarify the effect of the spore-forming and lactic acid-producing probiotic strain, Bacillus coagulans SANK 70258, on human colonic microbiota of healthy subjects and ulcerative colitis patients. A model culture system was employed to construct the in vitro human colonic microbiota, to retain the bacterial species richness and simulate the patient's disordered composition, from the fecal inoculum. Bacterial 16S rRNA gene sequencing confirmed that administration of B. coagulans SANK 70258 (at an initial concentration of 4 × 10-total cells/mL) suppressed bacteria related to the family Enterobacteriaceae in the microbiota models for both healthy subjects (P = 0.016) and ulcerative colitis patients (P = 0.023). In addition, administration of B. coagulans SANK 70258 increased bacteria related to the family Lachnospiraceae (P = 0.031), thereby enhancing butyrate production (P = 0.031) in the microbiota models of healthy subjects. However, these changes were not observed in the microbiota models of ulcerative colitis patients, likely owing to the low abundance of Lachnospiraceae species. This study demonstrates the potential of B. coagulans SANK 70258 to exhibit antimicrobial activity against harmful organisms in patients with ulcerative colitis, while improving the intestinal microenvironment by increasing butyrogenesis in healthy persons. KEY POINTS: • B. coagulans SANK 70258 treatment reduced colonic Enterobacteriaceae species. • B. coagulans SANK 70258 treatment enhanced butyrogenesis in healthy individuals. • B. coagulans SANK 70258 treatment increased Lachnospiraceae in healthy persons. • B. coagulans SANK 70258 improves the colonic microenvironment in ulcerative colitis.