Study of antimicrobial activity of alkyl dimethylbenzylammonium chloride and didecyl dimethylammonium chloride in disinfectant composition against bee pathogens in vitro

The rise in the prevalence of infectious diseases among honey bees has prompted practitioners, scientists, and veterinarians to seek out novel, efficacious products to prevent and treat contagious bee diseases. In vitro testing of disinfectants enables the determination of the viability of continued use of the products in beekeeping. The objective of this study was to investigate the antimicrobial activity of alkyl dimethylbenzylammonium chloride and didecyl dimethylammonium chloride, constituents of the disinfectant Brovadez-plus, against pathogenic bee bacteria in vitro. Isolated cultures of bee bacteria, which produce dyspeptic diseases in bees, served as research materials. To determine the antimicrobial activity of «Brovadez plus» the disco diffusion method was applied. The bactericidal effect of «Brovadez plus» was registered at the action of 1 % and 1.5% solution of disinfectant against bacteria of Klebsiella pneumoniae species on the 1st day of research at the zone level of growth inhibition 8.2 ± 0.42 mm and 9.4 ± 0.27 mm, respectively. The largest diameter of bacteriostatic effect was registered on the first and third days of the experiment at the concentration of «Brovadez plus» 1.5 % (24.2 ± 0.22 mm). Under the action of this product against bacteria of Klebsiella (Enterobacter) aerogenes species was registered bacteriostatic effect after 24 hours at all tested concentrations at the zone level of growth inhibition of 9.8 ± 0.42 mm (0,05 %) ― 22.2 ± 0.42 mm (1.5%). After 120 hours a gradual bactericidal effect of «Brovadez plus» in contact with these investigated pathogenic enterobacteriaceae was registered. The bacteriostatic activity of «Brovadez plus» on a mixed culture of microorganisms at 24 hours of the experiment at concentrations of 0.5% (18.2 ± 0.42); 1 % (19.2 ± 0.42 mm) and 1.5% (21.6 ± 0.45 mm) was registered. The inhibition of microbial growth in this culture increased with time when cultured in the thermostat at 37.4 °C. The bacteriostatic and bactericidal effects resulting from the complex mechanism of action of «Brovadez plus» at concentrations of 0.05 %, 0.1 %, 0.25 %, 0.5 %, 1 %, 1.5 % on bee enterobacteriosis in the laboratory (in vitro) were investigated