In vitro antimicrobial effect of bacteriocin PsVP-10 in combination with chlorhexidine and triclosan against Streptococcus mutans and Streptococcus sobrinus strains.

Objectives: To determine the minimal inhibitory concentrations (MICs) of bacteriocin PsVP-10, chlorhexidine and triclosan on S. mutans and S. sobrinus and to study the potential synergistic combination between these antimicrobial and the bacteriocin PsVP-10.

Design: Were determined MICs of bacteriocin PsVP-10, triclosan and chlorhexidine on strains of S. mutans and S. sobrinus, which formed a biofilm or did not form a biofilm. In addition, the synergistic effect was analysed by the determination of respective fractionary inhibitory concentrations (FICs) between bacteriocin PsVP-10 plus chlorhexidine and bacteriocin PsVP-10 plus triclosan.

Results: MICs of three antimicrobials used were higher in those bacterial strains, which formed a biofilm. An interesting synergistic effect on both studied species was observed when bacteriocin and chlorhexidine were combined. A slighter synergy was determined for the combination bacteriocin PsVP-10 and triclosan.

Conclusions: The results showed that the combination of chlorhexidine bacteriocin PsVP-10 could reduce the number of cariogenic bacteria for in vitro studies. In the future this synergistic combination could be an alternative to antimicrobial therapy against S. mutans or S. sobrinus.