Propolis nanoparticle enhances antimicrobial efficacy against Enterococcus faecalis biofilms

Propolis is a natural product that is collected by honey bees from parts of plants, buds, and exudates. The gen-eral composition of this substance varies in different geographical locations and climates. The biological char-acteristics of propolis are attributed to its chemical composition especially polyphenols and flavonoids. In recent years, the current trend has been towards the identification of natural products in disinfection. In addition, Nanoparticles are able to penetrate bacteria and bacterial biofilms, so they can be a potential agent for controlling the growth of bacterial infections. Therefore, this study aimed to investigate the antimicrobial efficacy of propolis and propolis nanoparticle (PN) as an endodontic irrigant against E. faecalis biofilm in vitro. PN was prepared by the ultrasonication method. Scanning electron microscopy and dynamic light scattering were used to measure the size and morphology of the produced nanoparticles. The antimicrobial and anti-biofilm activity of Iranian propolis (IP), PN and sodium hypochlorite (5.25% NaOCl) against E. faecalis (PTCC 1778) were assessed. Results indicated that PN, at a concentration 10 times lower, was more effective against E. faecalis (PTCC 1778) than IP (p <0.001). Also, PN was able to inhibit the adhesion of E. faecalis biofilm at lower concentrations than IP (p <0.001) which could be due to the reduced particle size, leading to better nanoparticle penetration. Further research is needed to investigate the synergistic effect of propolis and PN in combination with endodontic irrigants and to understand their mechanism of action.(c) 2022 SAAB. Published by Elsevier B.V. All rights reserved.

Automated summary

Propolis and propolis nanoparticles (PN) show potential as antimicrobial agents for controlling bacterial infections. PN exhibits better antimicrobial and anti-biofilm activity, possibly due to its smaller particle size that allows for better nanoparticle penetration.