Bacillus coagulans idrc019 Attenuates Irritable Bowel Syndrome by Revealing Multimodal Protective Mechanisms

Bacillus coagulans has attracted widespread attention in the treatment of irritable bowel syndrome due to its multiple probiotic functions, yet its specific molecular mechanisms remain unclear, and the efficacy of probiotics exhibits significant strain specificity, posing a key bottleneck for practical application. To address this, this study obtained a bile salt-tolerant B. coaguans idrc019 through in vitro screening. This strain demonstrated strong survival and germination in simulated gut conditions, supporting effective intestinal colonization. Further evaluation in an IBS animal model revealed that idrc019 alleviated visceral hypersensitivity and colonic inflammation in a dose-dependent manner. Through enhanced intestinal barrier integrity, microbiota modulation (e.g., Actinobacteria restoration), and elevated metabolites (e.g., kynurenine), the strain exerted IBS-alleviating effects via synchronized immune, microbial, and metabolic regulation. Our findings offer a mechanistically grounded probiotic candidate, underscore functional screening as a critical strategy, and pave the way for clinical application.