Effect of Disinfectants with Different Active Ingredients on Biofilm Formation in Pseudomonas aeruginosa.

We compared the effects of disinfectants on biofilms of 10 Pseudomonas aeruginosa strains isolated from different loci of patients with purulent-septic infections. Identification was carried out by standard bacteriological methods. To substantiate the prospects of using in hospitals and to assess the effect of disinfectants on P. aeruginosa biofilms, the following disinfectants were used in various concentrations: Sekusept Aktiv, A-DEZ, and Monitor Oxy. All clinical strains of P. aeruginosa showed the ability to form biofilms. Both oxygen-containing and quaternary ammonium compounds effectively inhibited the formation of biofilms. In more than 50% cases, disinfectants with different active ingredients did not destroy pre-formed of P. aeruginosa biofilms.

Simulation of bacterial biofilms and estimation of the sensitivity of healthcare-associated infection pathogens to bactericide Sekusept active.

The effect of bactericide Sekusept active (B SA), a peracetic acid-based preparation, on microbial strains, isolated from patients with severe infectious diseases who were treated in a regional children's multi-specialty hospital, was studied. Based on the biochemical identification, the strains were classified as gram-negative non-fermenting bacteria (22 strains), Enterobacteriaceae family (18 strains), and bacilli - 3 strains. The biocidal activity of B SA was evaluated by the degree of inhibition of the growth of bacterial cells, existing in the planktonic form and in the form of biofilm (on a flat-bottomed plastic immunological tablet). It was shown that all the studied strains had the ability to biofilm formation, most of them (67,4%) formed moderately pronounced biofilms, and non-fermenting bacteria had a particularly pronounced coefficient of biofilm formation. The selected concentrations of B CA inhibited the growth of planktonic cells, and the ability of bactericide to prevent the formation of biofilms depended on the concentration (the most effective concentrations were 0,8 and 3,0%). Sensitivity of the strains existed in the aged biofilm to the bactericide was significantly lower, especially resistant to this effect were biofilms formed by non-fermenting bacteria and representatives of fam. Enterobacteriaceae. Our results confirm the importance of testing the effectiveness of biocides not only in accordance with standard methods developed for microorganisms in planktonic form, but also for biofilms.