IADR Abstract Archives
Broad-Spectrum Antimicrobial Effects of a Novel Quaternary Ammonium Compound.
Objectives: Human diseases in general, and oral infections in particular, are caused by several biofilm-forming bacteria and yeasts. Benzyl-dimethyl-[3-(tetradecanoylamino)propyl]azanium chloride (miramistin/MIR), is a novel quaternary ammonium compound. Little is known about its effects on biofilms. The aim of this work was to determine the antimicrobial and antibiofilm effects of MIR against purposely selected oral pathogens.
Methods: The antimicrobial effects of MIR were determined against planktonic cells of Streptococcus mutans, Actinomyces naeslundii and Candida albicans by measuring the minimum inhibitory concentration (MIC) and minimum bactericidal/fungicidal concentration (MBC/MFC). Monospecies biofilm eradication by MIR was determined against 24h using the standard XTT reduction assay. The effects of MIR against mature (72h) biofilms were determined and compared with untreated controls. GraphPad Prism 9 software was used to plot dose-response curves. For 72h biofilms, the data were analysed using one-way ANOVA with Tukey’s HSD post-hoc test and one-sample t-test at significance of α=0.05.
Results: MIR potently killed planktonic cells at low micromolar concentrations (MIC for S. mutans, A. naeslundii and C. albicans = 9.11 μM). The minimum biofilm eradication concentration (MBEC80) was determined to be 86.23 µM for S. mutans, 88.03 µM for A. naeslundii and 64.18 µM for C. albicans. MIR (145.75 µM) significantly reduced biofilm viability of 72h biofilms compared to untreated control for all the 3 organisms (p<0.001).
Conclusions: This study provides evidence that MIR potently kills planktonic and biofilm cells of bacterial and fungal species, highlighting the potential to develop MIR into a broad-spectrum anti-infective agent.
Methods: The antimicrobial effects of MIR were determined against planktonic cells of Streptococcus mutans, Actinomyces naeslundii and Candida albicans by measuring the minimum inhibitory concentration (MIC) and minimum bactericidal/fungicidal concentration (MBC/MFC). Monospecies biofilm eradication by MIR was determined against 24h using the standard XTT reduction assay. The effects of MIR against mature (72h) biofilms were determined and compared with untreated controls. GraphPad Prism 9 software was used to plot dose-response curves. For 72h biofilms, the data were analysed using one-way ANOVA with Tukey’s HSD post-hoc test and one-sample t-test at significance of α=0.05.
Results: MIR potently killed planktonic cells at low micromolar concentrations (MIC for S. mutans, A. naeslundii and C. albicans = 9.11 μM). The minimum biofilm eradication concentration (MBEC80) was determined to be 86.23 µM for S. mutans, 88.03 µM for A. naeslundii and 64.18 µM for C. albicans. MIR (145.75 µM) significantly reduced biofilm viability of 72h biofilms compared to untreated control for all the 3 organisms (p<0.001).
Conclusions: This study provides evidence that MIR potently kills planktonic and biofilm cells of bacterial and fungal species, highlighting the potential to develop MIR into a broad-spectrum anti-infective agent.