STUDY OF THE MINIMUM BACTERICIDAL CONCENTRATION OF POLYHEXAMETHYLENEGUANIDINE, SILVER PREPARATIONS AND DIMEXIDE ON TEST-CULTURES OF MICROORGANISMS

Modern, highly efficient animal husbandry technologies provide for their significant accumulation in a limited area. In addition, this increases the requirements for choosing high-quality, environmentally friendly means for disinfection. In this regard, highly effective and safe drugs are polyhexamethyleneguanidine, silver drugs and dimexide, the composition of which can be an effective disinfectant in the future. That is why the work aimed to establish the minimum bactericidal concentration of polyhexamethyleneguanidine, colloidal silver, silver nanoaquachelates and dimexide on test cultures of microorganisms S. aureus, E. coli, B. subtilis, C. albicans. Microbiological studies on the determination of the minimal bactericidal effect of the test substances were carried out in two stages: by well and suspension methods following the methodological recommendations "Study of the specific activity of antimicrobial drugs" (Volyansky et al., 2004) and "Determination of the bactericidal activity and control of the absence of bacteriostatic effect of disinfectants" (Kovalenko, 2019). At the first stage of the study, it was established that a 0.1 % solution of silver nanoaquachelate has a higher bactericidal effect on test cultures of S. aureus, E. coli, B. subtilis, compared to a 10 % solution of colloidal silver. The results of the second stage of research showed that polyhexamethyleneguanidine and silver nanoaquachelates have bactericidal activity on test cultures of microorganisms S. aureus, E. coli, C. albicans in very low concentrations, namely: no growth of S. aureus was observed even at a concentration of polyhexamethyleneguanidine of 0, 00625 % for 20 min and 0.003125 % during 40 min, E. coli at concentrations of 0.003125 % and 0.001562%, respectively, and C. albicans regardless of the time regime at concentrations of 0.00625 %. The bactericidal effect of silver nanoaquachelates against S. aureus was manifested at a concentration of 0.005 % for 20 minutes. and 0.0025 % for 40 min, E. coli at concentrations of 0.0025 % and 0.00125 %, respectively, and C. albicans regardless of exposure time at concentrations of 0.0025 %. The effectiveness of dimexide concerning the specified test cultures of the studied microorganisms was observed at a much higher concentration at 0.4 % concerning S. aureus regardless of the time of action, E. coli at a concentration of 0.3 % for 20 minutes, respectively. action and 0.2 % within 40 min actions, and C. albicans regardless of exposure time at a concentration of 0.3 %.