Colonization of Clostridium butyricum in Rats and Its Effect on Intestinal Microbial Composition

Gut microorganisms participate in many physiological processes. In particular, Clostridium butyricum can modulate gut microorganisms and treat diseases. The colonization and persistence of strains in the gut contribute to beneficial effects, and the colonization by C. butyricum in the gut is currently unknown. We investigated the total intestinal contents of C. butyricum at 12 h, 24 h, 48 h, and four and six days using real-time reverse transcription-PCR, after oral administration of C. butyricum to rats for seven consecutive days. We assessed the bacterial community structure using Illumina MiSeq sequencing. The results showed that C. butyricum was mainly colonized in the colon. The total content of C. butyricum in the gut increased significantly at 12 h after administration. Exogenous C. butyricum could still be detected in the gut six days after administration. Administration of C. butyricum significantly enhanced gut microbial diversity. The relative abundance of short-chain fatty acid-producing bacterial genera was shown to be higher than that of the control group, and treatment with C. butyricum elevated Firmicutes and diminished Bacteroidetes phyla compared with to the control group. These findings laid the foundation for the study of probiotic colonization capacity and the improvement of microflora for the prevention of gut diseases.