Effect of intervention with Bifidobacterium animalis subsp. lactis BLa80 on the composition of the gut microbiota of healthy volunteers: a placebo-controlled randomized trial.

Probiotics are live microorganisms that confer a health benefit on the host. Nevertheless, there is few pertinent research on the impact of probiotics on the healthy individuals. Therefore, a placebo-controlled randomized trial was conducted to investigate the effects of Bifidobacterium animalis subsp. lactis BLa80 supplementation on the gut microbiota composition in healthy individuals. A total of 112 participants were assigned to two groups: a placebo group that received maltodextrin, and a BLa80 group that received a combination of maltodextrin and strain BLa80 at a dosage of 1 × 1010 colony-forming units per day. The study duration was 8 weeks and 16S rRNA sequencing was employed to analyze changes in gut microbiota. Furthermore, the study assessed the metabolic effects of BLa80 by monitoring alanine transaminase (ALT), aspartate aminotransferase (AST), and uric acid (UA). The BLa80 intervention demonstrated the ability to modulate the gut microbiota and significantly increase the proportion of Bifidobacterium spp. The BLa80 intervention markedly reduced metabolic pathways associated with Biofilm formation-Pseudomonas aeruginosa, cationic antimicrobial peptide (CAMP) resistance and other metabolic pathways associated with conditionally pathogenic bacteria and CAMP. No adverse effects were reported throughout the study. Additionally, the BLa80 intervention slowed the increase in uric acid levels compared to the placebo group. For the primary outcome, these results demonstrate that BLa80 is capable of transient enrichment in the human intestine. Additionally, BLa80 was effective in increasing the relative abundance of beneficial bacteria. In conclusion, the observed beneficial effects position BLa80 as a promising probiotic strain.