Effect of selected biofilm inhibitors, N-acetylcysteine and DNase, on some biological properties of taurine haloamines (TauCl and TauBr)

Abstract

Antibiotic resistance is a common problem accompanying biofilm-associated chronic infections. New therapeutic strategies are based on a combined application of antiseptics with anti-biofilm agents. Taurine haloamines, taurine chloramine (TauCl) and taurine bromamine (TauBr), show antimicrobial and anti-inflammatory properties, which have been examined in a variety of local infections, including biofilm- associated infections. In contrast to beneficial antimicrobial effects of taurine haloamines against the planktonic form of bacteria, their efficacy against bacteria hidden in biofilm need to be enhanced. One possibility is to use them together with agents capable of destroying components of biofilm matrix. In this study we ask a question whether TauCl or TauBr are effective in killing Streptococcus mutans and Porphyromonas gingivalis, major oral bacteria responsible for the development of dental plaque and pathogenesis of periodontal diseases. Moreover, we have examined TauBr and TauCl stability in the presence of N-acetylcysteine (NAC ) and DN ase, agents with known anti-biofilm activity. We have found that TauBr was much stronger than TauCl microbicidal agent against both tested bacterial strains. However, TauBr was less stable than TauCl. NAC readily decomposed TauBr but not TauCl. In addition, TauBr inhibited DNase activity, when used in excess. This preliminary study confirms previous opinions that taurine haloamines have great potential in killing oral bacteria. However, further studies are necessary to find anti-biofilm agent(s) which together with TauCl/TauBr will give at least an additive therapeutic effect in the treatment of chronic infections, to support or replace ineffective antibiotic therapy.