Antimicrobial and anti-biofilm activities of Lactobacillus kefiranofaciens DD2 against oral pathogens

J Oral Microbiol. 2018 May 28;10(1):1472985. doi: 10.1080/20002297.2018.1472985. eCollection 2018.

Abstract

Background: Streptococcus mutans and Streptococcus sobrinus are major causative bacterial pathogens of dental caries. Objective: We investigated the applicability of three Lactobacillus strains (L. kefiranofaciens DD2, DD5, and DD6) isolated from kefir and three commercial Lactobacillus strains (L. plantarum ATCC 10,012, L. johnsonii JCM 1022, and L. rhamnosus ATCC 7469) as potential oral probiotics with respect to their survivability in an experimental oral environment, antimicrobial activity, and anti-biofilm formation activity against S. mutans and S. sobrinus. Results: Strains DD2, ATCC 10012, ATCC 7469, and JCM 1022 had the best oral survivability, including aerotolerance and enzymatic resistance, and inhibited the growth and biofilm formation of S. mutans and S. sobrinus. In particular, DD2 suppressed all three classes of biofilm formation-associated genes: those associated with carbohydrate metabolism and those encoding regulatory biofilm and adhesion proteins. Conclusions: These results indicate that the novel kefir isolate L. kefiranofaciens DD2 effectively and directly inhibits S. mutans and S. sobrinus.

Keywords: Kefir; Lactobacillus kefiranofaciens; Streptococcus mutans; Streptococcus sobrinus; artificial oral model system; dental caries; oral biofilm; oral probiotics.

Grants and funding

This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2017R1D1A1B03035427). In addition, this paper was supported by the KU Research Professor Program of the Konkuk University.