Lactobacillus Helpful Against Oral Pathogens

Aim:  To determine the inhibitory effect of oral Lactobacillus against putative oral pathogens.

Methods and Results:  Total 357 strains comprising 10 species of oral Lactobacillus, Lactobacillus fermentum (195), Lactobacillus salivarius (53), Lactobacillus casei (20), Lactobacillus gasseri (18), Lactobacillus rhamnosus (14), Lactobacillus paracasei (12), Lactobacillus mucosae (12), Lactobacillus oris (12), Lactobacillus plantarum (11) and Lactobacillus vaginalis (10) were used as producer strains. Inhibitory effect against a panel of indicators, periodontitis- and caries-related pathogens, was assessed. 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. Lactobacillus SD1-SD6, representing the six species with the strong inhibitory effect, inhibited growth of Streptococcus mutans ATCC 25175 in the biofilm model. Also, it was demonstrated that growth of S. mutans was inhibited in a mixture with L. paracasei SD1. The inhibition was enhanced in acidic condition and 5% glucose.

Conclusion:  The results have shown that oral Lactobacillus SD1-SD6 showed a strong inhibitory effect against S. mutans and Streptococcus sobrinus, as well as, gram-negative periodontal pathogens Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans.