Antimicrobial Activity of Dioxidine Against Strains of Potential Pathogens of Otorhinolarygological Infections

Resumo

We present here the results of our studies of the in vitro antibacterial and antifungal activity of dioxidine (hydroxymethylquinoxaline dioxide) against 32 strains of bacteria and fungi. Dioxidine was found to exhibit high levels of activity against two of the anaerobic bacteria tested: Peptostreptococcus anaerobius and Bacillus fragilis (MIC ≤ 0.125 μg/ml). Dioxidine was moderately active against Gram-negative bacteria (MIC 8 – 64 μg/ml) apart from Pseudomonas aeruginosa (MIC = 1024 μg/ml) and Stenotrophomonas maltophila (MIC = 512 μg/ml). Dioxidine inhibited the growth of Gram-positive bacteria but at higher concentrations than for Gram-negative bacteria (MIC 64 – 1024 μg/ml). Dioxidine at 1024 μg/ml delayed the growth of yeast-like fungi of the genus Candida (C. albicans). The mold fungus Aspergillus niger was resistant to dioxidine (MIC > 4096 μg/ml).