16S rRNA Gene Amplicon Sequencing of Gut Microbiota Affected by Four Probiotic Strains in Mice

Simple Summary The overuse of antibiotics has led to an increase in resistant bacteria and unnecessary culture contamination. As one of the best green pollution-free antibiotics, probiotics and their preparations have become research hotspots. The different effects of different probiotics on gut microbiota are still unclear. In this study, the gut microbiota of mice treated with Lactobacillus acidophilus, Lactobacillus plantarum, Bacillus subtilis and Enterococcus faecalis for 14 days was assessed used 16S amplificon sequencing. The results showed that the four probiotics caused changes in the composition and structure of the gut microbiota in mice, but they did not cause changes in the diversity of the gut microbiota. These results provide a strong basis for the preparation of probiotics and theory regarding their targets. Probiotics, also referred to as "living microorganisms," are mostly present in the genitals and the guts of animals. They can increase an animal's immunity, aid in digestion and absorption, control gut microbiota, protect against sickness, and even fight cancer. However, the differences in the effects of different types of probiotics on host gut microbiota composition are still unclear. In this study, 21-day-old specific pathogen-free (SPF) mice were gavaged with Lactobacillus acidophilus (La), Lactiplantibacillus plantarum (Lp), Bacillus subtilis (Bs), Enterococcus faecalis (Ef), LB broth medium, and MRS broth medium. We sequenced 16S rRNA from fecal samples from each group 14 d after gavaging. According to the results, there were significant differences among the six groups of samples in Firmicutes, Bacteroidetes, Proteobacteria, Bacteroidetes, Actinobacteria, and Desferribacter (p < 0.01) at the phylum level. Lactobacillus, Erysipelaceae Clostridium, Bacteroides, Brautella, Trichospiraceae Clostridium, Verummicroaceae Ruminococcus, Ruminococcus, Prevotella, Shigella, and Clostridium Clostridium differed significantly at the genus level (p < 0.01). Four kinds of probiotic changes in the composition and structure of the gut microbiota in mice were observed, but they did not cause changes in the diversity of the gut microbiota. In conclusion, the use of different probiotics resulted in different changes in the gut microbiota of the mice, including genera that some probiotics decreased and genera that some pathogens increased. According to the results of this study, different probiotic strains have different effects on the gut microbiota of mice, which may provide new ideas for the mechanism of action and application of microecological agents.