Potential Antagonistic Activity of Bifidobacterium adolescentis against Porphyromonas gingivalis in a Hamster Periodontitis Model

The antagonistic activity of Bifidobacterium adolescentis against Porphyromonas gingivalis was investigated in a hamster periodontitis model. Experimental periodontitis was induced by a silk-suture that was placed around the first molar of the lower jaw and inoculation with P. gingivalis. Real-time PCR was applied for the enumeration of P. gingivalis. Three B. adolescentis strains were individually used to inoculate the oral cavity for five weeks. In this study, B. adolescentis OLB6410 and KH96 were recovered from the oral cavity of hamsters and they seemed to weakly inhibit (p < 0.1) the growth of P. gingivalis as compared with the control group. In contrast, OLB6398 did not affect the growth of P. gingivalis. Although the results did not reach significance, we propose a hypothesis whereby colonizing B. adolescentis potentially competes with P. gingivalis. This study sheds new light on the development of probiotics for the prevention of periodontal disease.