Antifungal activity of arginine based-surfactants against yeasts

FAIT, M.E.; MYLEK, S.; GRILLO, P.; COTABARREN, J.; PRIETO, E.; GARROTE, G.L.; VÁZQUEZ, R.F.; MORCELLE, S.R.; BAKÁS, L.

Congreso; XLVII Reunión Anual de la Sociedad Argentina de Biofísica; 2018

SAB

The antifungal activity of two novel arginine-based compounds (Bz-Arg-NHC10 andBz-Arg-NHC12), which were synthesized by an enzymatic strategy, was studiedagainst different Candida species, using two clinical isolates (C. albicans and C.tropicalis) and the strain Candida albicans ATCC 64548 from the American TypeCulture Collection (ATCC, Manassas, USA) as indicator microorganisms. Cetrimide(alkyl trimethyl ammonium bromide mixture), a commercial cationic disinfectantwas used for comparison. Minimum Inhibitory Concentrations (MIC) werecalculated from DO measurements after 24 h of exposure to the compounds.Results were corroborated using the resazurin assay. Minimum FungicidalConcentrations were also obtained. The three surfactants proved antifungalactivity against all isolates, revealing their potential use as effective disinfectants.The effect of surfactants on pathogens survival was analyzed in SabouraudDextrose Broth added with Bz-Arg- NHC10 or Bz-Arg-NHC 12 at differentconcentrations. Viability curves showed a decrease of the number of viablemicroorganism after 24 h of incubation when compared to that of the control inabsence of the surfactant. Experiments in lipid monolayers composed bydioleoylphosphatidylcholine (PC), phosphatidylethanolamine (PE) and ergosterol(ERG) confirmed that both surfactants can insert in the fungal membranes,suggesting it as a possible target for the antifungal activity. Morphological changesin yeasts exposed to the surfactants were analyzed by AFM. Finally, antiadhesiveactivity was studied pretreating polyestyrene microplates with different surfactantconcentrations. Overall, the evidence from this preliminary study supports the useof these arginine-based surfactants as an alternative to commercial cationicsurfactants, especially for their use as additives in topical formulations and forsuperficial disinfection.