A. O. Sharova, N. I. Hrynchuk, D. M. Dudikova, V. V. Nedashkivska, Z. S. Suvorova, N. O. Vrynchanu
Antibacterial activity of 4-(adamantyl)-(1-aminobutyl) benzole against S. aureus biofilms

   Biofilm formation is considered as a serious medical problem due to its resistance to antibacterials and
disinfectants, high treatment costs and the increase of the lethal complications rate. Therefore, there is a
constant demand for the new compounds possessing a distinct activity against mature biofilm on the different
stages of its formation.
   The aim of the study was to investigate the effect of compound AM-166 on S. aureus biofilms in comparison
to antibacterial drugs.
   Strain susceptibility to tested compound AM-166 and antibacterials (ciprofloxacin, azithromycin, gentamicin,
rifampicin) was performed using minimum inhibitory concentration (MIC) determination by broth
microdilution method and areas of growth retardation by disk diffusion method. Antibiofilm activity was
determined by the crystal violet assay.
   Our studies have shown that compound AM-166 possessed a distinct antibiofilm activity on the different
stages of biofilm formation. The compound at 5,0 × MIC concentration reduced biofilm formation at an
early stage by 7,4–27.3 %. Treatment of S. aureus 24-h mature biofilm with compound resulted in superior
or comparable antibiofim action compared with referent antimicrobials. Against 48-h mature biofilms
compound demonstrated more pronounced effect than ciprofloxacin, azithromycin and gentamicin.
AM-166 prevented S. aureus biofilm formation on polyurethane catheters, compound’ activity was superior
to ciprofloxacin and azithromycin.
   The data obtained suggest the promises of adamantane derivative AM-166 for the development of new
antimicrobial drugs.

Key words: adamantane derivative, antibacterial activity, S. aureus, biofilms