Oral Lactobacillus species and their probiotic capabilities in patients with periodontitis and periodontally healthy individuals

This study aimed to identify oral Lactobacillus species and characterize their adhesion properties and antibacterial activity in patients with periodontitis compared with periodontally healthy individuals.Three hundred and fifty-four isolates from the saliva, subgingival, and tongue plaque of 59 periodontitis patients and 59 healthy individuals were analyzed. Oral Lactobacillus species were identified through the culture method in the modified MRS medium and confirmed by molecular testing. Moreover, the radial diffusion assay and cell culture methods were used to determine the antibacterial activities of oral strains against oral pathogens and their adhesion activity in vitro.67.7% of the cases and 75.7% of the control samples were positive for the Lactobacillus species. Lacticaseibacillus paracasei and Limosilactobacillus fermentum were the dominant species in the case group, whereas Lacticaseibacillus casei and Lactiplantibacillus plantarum were dominant in the control group. Lactobacillus crispatus and Lactobacillus gasseri had higher antibacterial effects against oral pathogens. Moreover, Ligilactobacillus salivarius and L. fermentum demonstrated the highest ability to adhere to oral mucosal cells and salivary-coated hydroxyapatite.L. crispatus, L. gasseri, L. fermentum, and L. salivarius can be introduced as probiotic candidates since they demonstrated appropriate adherence to oral mucosal cells and salivary-coated hydroxyapatite and also antibacterial activities. However, further studies should be conducted to assess the safety of probiotic interventions using these strains in patients with periodontal disease.