Propolis:anti-Porphyromonas gingival activity and synergism with ornidazole

Objectives: To evaluate inhibitory action of propolis and synergism between propolis and ornidazole on Porphyromonas gingival (P.g) growth in vitro. Methods: Minimal bactericidal concentration(MBC) of propolis for P.g was determined by the fluid dilution method. Synergism assay between propolis(100mg/mL,50mg/mL,25mg/mL) and ornidazole(0.5mg/mL, 0.4mg/mL, 0.3mg/mL, 0.2mg/mL, 0.1mg/mL) on P.g was carried out by the disk diffusion method and the data was analyzed statistically by F test.Results: MBC of propolis for P.g was 1.56mg/mL,which was equal to 0.125 mg/L to 0.25 mg/L ornidazole.The mean value (mm) of the inhibitory zone of 100mg/mL, 50mg/mL and 25mg/mL propolis in the disk diffusion method were 10.25,9.0 and 8.0 respectively.The seemingly bacteriostasis of propolis for P.g was not ideal,which shew the noticeable difference from the result in the fluid dilution method.But the size of microbial inhibitory zone (mm) of the mixture groups with 100mg/mL propolis were all more than the ornidazole groups and these observations existed in 50mg/mL and 25mg/mL propolis groups mixtured with ornidazole at low concentration.The values of the inhibitory zone of the mixtures were increased with increasing of propolis concentration.The statistical results indicated there was interaction between propolis and ornidazole(P<0.001).Conclusion: Although the further studies about propolis are needed to define the efficacy.This study had indicated the ideal inhibitory action of propolis on P.g growth and could determine the potential medical use of propolis in combination with ornidazole on periodontal diseases.