ABSTRACT

The aim of the study was to compare Pseudomonas sp. strain isolated from distilled water and grown on the sterile filtrate from this water with the referent strain of Pseudomonas aeruginosa NCTC 6749 grown under the standard conditions, with the respect to their sensitivity to eight common disinfectants. Partly modified EN 1040 method was applied. The reduction factor (RF) for at least five concentrations of each of the products were determined. The linear relationship between concentration of the disinfectants and RF was  established in a graphic form. Sensitivity of the strains was compared at the RF = 4. The WS strain was found to be more sensitivity than the referent strain to the disinfectants. The ratio concentrations of the solutions that were effective during 15 minutes against both the strains were; 1,3 for ethyl alcohol; 2,1 for glutaraldehyde; 1,7 for formalin; 1,85 for phenol. In the case of chloramine-T, the sodium salt of dichloroisocyanuric acid, and peracetic aetd the ratios of concentrations were 156,0; 96,5 and 21,5 respectively. They indicate much higher sensitivity of the strain isolated from distilled water to these chemicals. Our study shows that Pseudomonas strain is more sensitive than referent strain to the following disinfectants: alcohols, aldehydes; chlorine, peroxygen and phenolic compounds. On the other hand Pseudomonas strain is less sensitive to quaternary ammonium compounds.