Inhibitory effect of Lactobacillus reuteri on periodontopathic and cariogenic bacteria

Abstract

The interaction between Lactobacillus reuteri, a probiotic bacterium, and oral pathogenic bacteria have not been studied adequately. This study examined the effects of L. reuteri on the proliferation of periodontopathic bacteria including Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, Porphyromonas gingivalis, and Tannerella forsythia, and on the formation of Streptococcus mutans biofilms. Human-derived L. reuteri strains (KCTC 3594 and KCTC 3678) and rat-derived L. reuteri KCTC 3679 were used. All strains exhibited significant inhibitory effects on the growth of periodontopathic bacteria and the formation of S. mutans biofilms. These antibacterial activities of L. reuteri were attributed to the production of organic acids, hydrogen peroxide, and a bacteriocin-like compound. Reuterin, an antimicrobial factor, was produced only by L. reuteri KCTC 3594. In addition, L. reuteri inhibited the production of methyl mercaptan by F. nucleatum and P. gingivalis. Overall, these results suggest that L. reuteri may be useful as a probiotic agent for improving oral health.

Antimicrobial Effect of Lactobacillus reuteri on Cariogenic Bacteria Streptococcus gordonii, Streptococcus mutans, and Periodontal Diseases Actinomyces naeslundii and Tannerella forsythia

“…There are some reports on the growth of these bacteria, although strains and culture media may differ to a point where growth kinetics is altered [21]. For example, L. reuteri isolated from human feces to treat against pathogenic gastrointestinal bacteria presented a similar slow growth dynamics as the one reported here [26].…”

“…On the other side, Kang et al [21] used the same T. forsythia strain as in this study; however, the lag phase lasted 8 h with a slower rate of growth.…”

“…When S. mutans is grown in anaerobic conditions, there is an absence of a lag phase and the exponential phase is stable for 8 h [21]. Other authors report the behavior of the same bacteria during biofilm formation on the surface of female rat teeth.…”

“…Some studies have shown promising results on the inhibition by L. reuteri isolated from humans and rats of both the growth of various oral pathogens, including T. forsythia, and biofilm formation [21]. Even more interesting is that antimicrobial property of L. reuteri appearing to be maintained when food products are used as a vector for their delivery.…”

Dual Effects of Lactobacilli as a Cholesterol Assimilator and an Inhibitor of Gastrointestinal Pathogenic Bacteria

“…The second solution was used without any changes in its composition. The prepared solutions were used as antimicrobial agents against the mentioned reference strains by the agar diffusion method (14,15). Thereafter, the mentioned reference strains were incubated at 37˚C for 24 h in the nutrient broth, then a suspension of each strain with 0.5 McFarland turbidity (1.5×10 8 cfu/mL) was prepared and inoculated evenly on the nutrient agar plates.…”