The impact of Bifidobacterium longum CCFM1112 on chronic constipation: a randomised, double-blind, placebo-controlled study.

A mounting body of evidence suggests that probiotics may mitigate constipation through their favourable modulation of gut microbiota and its metabolic byproducts. The precise mechanisms underlying this effect remain to be fully elucidated. This randomised, double-blind, placebo-controlled study investigates the clinical efficacy of Bifidobacterium longum (B. longum) CCFM1112 in treating chronic constipation. Fifty-six volunteers diagnosed with chronic constipation according to the Rome IV criteria were randomly assigned to either the B. longum CCFM1112 group or a placebo group for a 4-week intervention. Key outcomes measured included weekly spontaneous bowel movements (SBM), stool consistency (Bristol Stool Form Scale [BSFS]), Patient Assessment of Constipation-Symptoms (PAC-SYM) questionnaire, and Quality of Life (PAC-QOL) questionnaire. In addition, gut microbiota was detected using metagenomic sequencing, and non targeted metabolomics was used to detect fecal and serum metabolites. Results demonstrated that B. longum CCFM1112 significantly reduced PAC-QOL scores and improved BSFS in patients with chronic constipation. Correlation analyses revealed that B. longum CCFM1112 significantly increased the abundance of the genera Blautia, Anaerobutyricum, and Streptococcus. Furthermore, the abundance of species, including Blautia massiliensis, Blautia sp. SC05B48, Anaerobutyricum hallii, and Streptococcus salivarius, was also significantly elevated. Furthermore, it elevated fecal levels of linoleic acid, gamma-aminobutyric acid (GABA), and arachidonic acid, while increasing L-glutamic acid and decreasing adenosine in serum. Our research findings provide evidence that the intake of B. longum CCFM1112 can alleviate constipation.