Antibacterial activity of propolis nanoparticles againstEnterococcus faecalis biofilm

Background and Aim : The presence of bacterial biofilm and its products in the root canal ofnecrosis is main etiological factor in the development of apical periodontitis. Antibiotics are usedin the treatment of biofilms but the current trend is towards the identification of natural productsin disinfection. Nanoparticles are able to penetrate bacteria and bacterial biofilms, so they can bea potential agent for controlling the growth of bacterial infections. The aim of this study was toinvestigate the antimicrobial efficacy of propolis nanoparticle (PN) as an endodontic irrigantagainst E. faecalis biofilm in vitro.Methods : In the present study, PN was prepared by the ultrasonication method. Scanning electronmicroscopy and dynamic light scattering were used to measure the size and morphology of theproduced nanoparticles. The PN and sodium hypochlorite (۵.۲۵% NaOCl) were evaluated in vitroagainst E. faecalis (PTCC ۱۷۷۸) by disk diffusion and broth micro-dilution method. The biofilmformation was assessed through the crystal violet staining and MTT assays.Results : The results indicated that PN was effective against E. faecalis biofilm. However, NaOClshowed strong antibacterial activity even at low concentrations. PN was able to inhibit the E.faecalis biofilm adherence at a sub-MIC concentration. Moreover, Electron micrographs indicatedthe inhibition of biofilms compared to control biofilms.Conclusion : PN was able to inhibit the adhesion of E. faecalis biofilm that could be due to thereduced particle size, better nanoparticle penetration and the synergistic impact of maincomponents in propolis. Further research is needed to investigate the synergistic effect of PN incombination with endodontic irrigants and to understand their mechanism of action.

کلیدواژه ها:

Antibacterial ، Biofilms ، E. faecalis ، Nanoparticles