Inhibitory Activity of Oral Lactobacillus Against Oral Pathogens

Abstract Objectives: To determine the inhibitory effect of oral Lactobacillus against putative oral pathogens. Methods: The selected strains of 10 species of oral Lactobacillus included Lactobacillus fermentum, Lactobacillus salivarius, Lactobacillus casei, Lactobacillus gasseri, Lactobacillus rhamnosus, Lactobacillus paracasei, Lactobacillus mucosae, Lactobacillus oris, Lactobacillus plantarum and Lactobacillus vaginalis were used as producer strains. Inhibitory effect against a panel of indicators, periodontitis- and caries-related pathogens, was assessed. Results: Most oral Lactobacillus was able to inhibit the growth of both periodontitis- and caries-related pathogens. The strongest inhibitory activity was associated with L. paracasei, L. plantarum, L. rhamnosus, L. casei and L. salivarius. Also, it was demonstrated that growth of S. mutans was inhibited in a mixture with L. paracasei and in a biofilm model. The inhibition was enhanced in acidic condition and 5% glucose. Conclusion: The results have shown that certain oral Lactobacillus showed a strong inhibitory effect against Streptococcus mutans and S. sobrinus, as well as, gram-negative periodontal pathogens Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans. The results indicated that Lactobacillus may be of benefit as probiotics for prevention of oral diseases.