Comparative mechanism based study on disinfectants against multidrug-resistant Acinetobacter baumannii.

ABSTRACT

Acinetobacter baumannii has emerged as a hospital-acquired pathogen and has spread in the hospital settings, leading to enhanced nosocomial outbreaks associated with high death rates. Therefore, the aim of the current study is to determine the effective concentration of disinfectants like sodium hypochlorite, hydrogen peroxide, and chlorine dioxide, against multidrug-resistant (MDR) strains of A. baumannii. In this study, we have investigated the effect of disinfectants on different MDR strains i.e. RS307, RS6694, RS7434, RS10953, RS122, and sensitive strain ATCC-19606 of A. baumannii, via differential growth curves analysis, disc diffusion assay, estimation of reactive oxygen species (ROS), lipid peroxidation, and protein carbonylation. All the results collectively showed that 1% sodium hypochlorite (P value < 0.0027), 2.5% hydrogen peroxide (P value = 0.0032), and 10 mM (P value = 0.017) chlorine dioxide significantly inhibit the growth of MDR strains of A. baumannii. A significant increase in the ROS generations, altered lipid peroxidation, and a decrease in protein carbonylation was also observed after treatment with disinfectants, which confirmed its ROS-dependent damage mechanism. These disinfectants also enhance the membrane leakage of reducing sugar, protein, and DNA. The current study highlights and recommends the use of 2.5% hydrogen peroxide to control the MDR strains of A. baumannii in the hospital setup. Therefore, the present results will help in selecting concentrations of different disinfectants for regular use in hospital setups to eradicate the multidrug-resistant A. baumannii from the hospital setup.