Mesaconate from Bacillus subtilis R0179 Supernatant Attenuates Periodontitis by Inhibiting Porphyromonas gingivalis in Mice

ABSTRACT Aims This research sought to assess the efficacy of Bacillus subtilis ( B. subtilis ) R0179 and explore potential metabolites in mitigating experimental periodontitis in mice induced by Porphyromonas gingivalis ( P. gingivalis ) ATCC 33277. Methods B. subtilis R0179 was administered to 8‐week‐old male C57BL/6J mice with periodontitis. Oral load of P. gingivalis ATCC 33277 and periodontal tissue loss were quantified. The cell‐free supernatant (CFS) was separated to assess its anti ‐ P. gingivalis effect. Proteomic and metabolomic analyses identified potential antibacterial components in the CFS, further evaluated for anti‐ P. gingivalis effects. Results B. subtilis R0179 significantly reduced P. gingivalis ATCC 33277 levels and mitigated periodontal tissue loss in mice. The CFS, rather than inactivated B. subtilis R0179 cells, exhibited antibacterial activity. Proteomic and metabolomic analyses identified mesaconate and citraconate as key antibacterial agents. Disk diffusion assays confirmed the efficacy of mesaconate against P. gingivalis , while citraconate had no effect. Mesaconate showed a dose‐dependent reduction in P. gingivalis ATCC 33277 population and periodontal tissue loss in mice. Conclusion These findings highlight B. subtilis R0179 and its metabolite mesaconate as promising candidates for therapeutic development against periodontitis by inhibiting P. gingivalis ATCC 33277 effectively.