Abstract: In order to investigate the gut benefits of Lactobacillus casei LC01, the impact of different LC01 doses on the intestinal microbiota and peristalsis in mice was evaluated. Based on MiSeq high-throughput sequencing, the modulatory effects of LC01 on the intestinal microbiota in normal mice and those with intestinal microbiota imbalance caused by penicillin were compared. The propulsion rate of ink was applied to estimate the effect of LC01 on intestinal peristalsis in mice with constipation. Results indicated that administration of LC01 significantly increased the relative abundance of Lactobacillus and Bacteroides, but decreased the abundance of the opportunistic pathogens Prevotella and Helicobacter in the gut of normal mice, evidencing that LC01 markedly regulates the mouse gut microbiota. Furthermore, after two weeks of intervention, the penicillin-treated group showed higher relative abundance of Bacteroides, Clostridum and Lactobacillus than the model group. Moreover, LC01 improved intestinal peristalsis in mice with constipation, and it was more effective at a viable cell count of 60 billion than at 30 billion. These results revealed that LC01 could exert a modulatory effect on the mouse intestinal microbiota and peristalsis, indicating that LC01 may have potential as a probiotic strain for human health.

Key words: Lactobacillus casei, intestinal microbiota, high-throughput sequencing, gastrointestinal transit