Effects Of Punicalagin On The Growth And Adhesion Of Periodontal Pathogens Under Different Conditions

Objective:To study the in vitro antibacterial activity of punicalagin against Porphyromonas gingivalis（P.g）and Fusobacterium nucleatum（F.n）in planktonic state and biofilm state.Methods:1.The minimum inhibitory concentrations（MIC）and minimum bactericidal concentration（MBC）of punicalagin on P.g and F.n were determined at different concentrations（16.000mg/m L、8.000mg/m L,4.000mg/m L,2.000mg/m L,1.000mg/m L,0.500mg/m L,0.250mg/m L,0.125mg/m L,0.060 mg/m L）;2.At 0h,4h,8h,12h,24h and 48h,the effects of punicalagin on the growth of P.g and F.n at1/2MIC,MIC and 2MIC concentrations were detected,and the growth curves were drawn.3.The adhesion ability of P.g and F.n in planktonic state was determined by spectrophotometer;4.The minimum biofilm inhibition concentration(MBIC₅₀)and the minimum biofilm reduction concentration(MBRC₅₀)of punicalagin against major periodontal pathogens were determined under the condition of bacterial biofilm.Results:1.The MIC of P.g and F.n were 2mg/m L,and the MBC were 4mg/m L.2.The effects of punicalagin on the growth of P.g showed that the negative control group（P.g）rapidly entered the logarithmic growth phase at 8h and the stationary growth phase at 24h,while the 1/2MIC group entered the logarithmic growth phase at 12h,indicating that the 1/2MIC concentration of punicalagin inhibited P.g and prolonged the time of entering the logarithmic growth phase by 4h.However,the growth curves of P.g in MIC group and2MIC group were relatively flat,and the growth of bacteria almost stopped.The effect of punicalagin on the growth of F.n showed that the negative control group（F.n）entered the logarithmic growth phase quickly,and the 1/2MIC and MIC groups entered the logarithmic growth phase at 8h,and the time to enter the logarithmic growth phase was prolonged for 8h,while the growth curve of 2MIC was almost unchanged and relatively flat.3.The concentrations of MIC,1/2MIC and 1/4MIC have inhibitory effects on the adhesion of P.g and F.n in planktonic state,and the concentrations of MIC and 1/2MIC can inhibit the adhesion of P.g and F.n to the tube wall by more than 50%.4.The MBIC₅₀of P.g and F.n was 4mg/m L,while the MBRC₅₀was 16mg/m L and 8mg/m L,respectively.Conclusion:Punicalagin is a kind of natural medicine,which can inhibit the planktonic and biofilm status of the main periodontal pathogens to a certain extent.