A balanced gut microbiota and their metabolites are necessary for the maintenance of the host’s health. The antibiotic-induced dysbiosis can cause the disturbance of the microbial community, influence the immune homeostasis and induce susceptibility to metabolic- or immune-mediated disorders and diseases. The Lactobacillus and their metabolites or components affect the function of the host’s immune system and result in microbiota-mediated restoration. Recent data have indicated that, by altering the composition and functions of gut microbiota, antibiotic exposure can also lead to a number of specific pathologies, hence, understanding the potential mechanisms of the interactions between gut microbiota dysbiosis and immunological homeostasis is very important. The Lactobacillus strategies for detecting the associations between the restoration of the relatively imbalanced microbiome and gut diseases are provided in this discussion. In this review, we discuss the recently discovered connections between microbial communities and metabolites in the Lactobacillus treatment of β-lactam antibiotic-induced dysbiosis, and establish the relationship between commensal bacteria and host immunity under this imbalanced homeostasis of the gut microbiota.

Soybeans possess unexpected flavors and are difficult to be absorbed by the gastrointestinal tract. Kefir grain fermentation provides diverse strains and bioactive compounds, which may enhance flavor and bioaccessibility. Third-generation sequencing was applied to analyze the microbial diversity in milk and soybean kefir grains in this study. In both types of kefir grains, the most common bacterial genus was Lactobacillus, and their fungal communities were dominated by Kazachstania. Lactobacillus kefiranofaciens was the most abundant species in kefir grains, while Lactobacillus kefiri showed a higher proportion in soybean kefir grains. In addition, the quantification of free amino acids and volatile flavor compounds in soybean solution and soybean kefir have shown the increased content of glutamic acid and a decreased amount of unpleasant beany flavor compounds, demonstrating that the nutritive value and sensory properties of soybean can be improved by kefir grain fermentation. Finally, the bioconversion of isoflavones during fermentation and in vitro digestion was evaluated, suggesting that fermentation is beneficial for aglycone formation and absorption. To conclude, kefir fermentation is proposed to change the microbial structure of kefir grains, promote the nutritional value of soybean-based fermented products, and provide possible solutions for the development of soybean products.