This research group plans to take patients with mild to moderate UC and diarrhea IBS diagnosed in the First Affiliated Hospital of Xinxiang Medical College as examples, and divide them into UC group and IBS group; Each group was randomly divided into two groups, namely, conventional treatment+probiotics group and conventional treatment+probiotics placebo group.Starting from the intervention of probiotics on intestinal flora to alleviate intestinal injury caused by UC and IBS patients, the indicators of intestinal flora, serum inflammatory factors, metabolites in vivo, intestinal barrier-related protein expression, and fecal short-chain fatty acid level were detected to explore the clinical efficacy, intestinal protective effect and mechanism of probiotics in adjuvant treatment of UC and IBS patients.To provide new methods and new ideas for refractory UC and IBS, so as to improve the cure rate of UC and IBS, reduce the recurrence rate, relieve the physical and mental pain and economic burden of patients, and provide new ideas for the development and utilization of functional probiotics. It also seeks biosafety evidence for the future use of probiotics in antibiotic environment.