IADR Abstract Archives
Novel Antimicrobial Compounds for Inhibition of Clinically Relevant Biofilms
Objectives: Biofilms are responsible for many human infections, including those of the oral cavity. The high tolerance of biofilms to physical and chemical removal necessitates research into novel agents and surfaces to inhibit their development. The objective of this research was to evaluate the antimicrobial and antibiofilm potential of novel agents (n=3) with potential for incorporation into biomaterials.
Methods: Minimum inhibitory concentrations (MICs) of the novel antimicrobial compounds and triclosan were established for 7 bacterial species and Candida albicans using a broth microdilution approach. Minimum biocidal concentrations (MBCs) were determined by culture on agar following MIC assessment. Antibiofilm assessment involved exposing preformed biofilms in 96-well plates to the antimicrobials. Regrowth of biofilm post treatment was then determined by optical density.
Results: All compounds had species dependent antimicrobial activity (MIC between 0.0098 and 100 μg/ml). With exception of P. aeruginosa and S. marcescens, planktonic cultures were all sensitive to triclosan. Antibiofilm activity occurred with triclosan at concentrations (25 and 100 mg/ml) higher than MICs. Staphylococcus aureus, P. mirabilis and S. marcescens biofilms were resistant to triclosan whilst biocidal activity was seen against S. aureus and P. mirabilis. A novel imidazolium salt, exhibited activity against all planktonic bacteria and C. albicans, except P. stuartii and P. aeruginosa, and was biocidal against E. coli, P. mirabilis, K. pneumoniae, S. marcescens and C. albicans. Antibiofilm effect was only evident with this agent for S. aureus.
Conclusions: A novel imidazolium compound was effective against a range of bacterial species and C. albicans in planktonic form. Further development of this compound is however required to eradicate equivalent biofilms.
Methods: Minimum inhibitory concentrations (MICs) of the novel antimicrobial compounds and triclosan were established for 7 bacterial species and Candida albicans using a broth microdilution approach. Minimum biocidal concentrations (MBCs) were determined by culture on agar following MIC assessment. Antibiofilm assessment involved exposing preformed biofilms in 96-well plates to the antimicrobials. Regrowth of biofilm post treatment was then determined by optical density.
Results: All compounds had species dependent antimicrobial activity (MIC between 0.0098 and 100 μg/ml). With exception of P. aeruginosa and S. marcescens, planktonic cultures were all sensitive to triclosan. Antibiofilm activity occurred with triclosan at concentrations (25 and 100 mg/ml) higher than MICs. Staphylococcus aureus, P. mirabilis and S. marcescens biofilms were resistant to triclosan whilst biocidal activity was seen against S. aureus and P. mirabilis. A novel imidazolium salt, exhibited activity against all planktonic bacteria and C. albicans, except P. stuartii and P. aeruginosa, and was biocidal against E. coli, P. mirabilis, K. pneumoniae, S. marcescens and C. albicans. Antibiofilm effect was only evident with this agent for S. aureus.
Conclusions: A novel imidazolium compound was effective against a range of bacterial species and C. albicans in planktonic form. Further development of this compound is however required to eradicate equivalent biofilms.