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.

<p>Successful Incidences of Controlling Multidrug-Resistant, Extensively Drug-Resistant, and Nosocomial Infection <em>Acinetobacter baumannii</em> Using Antibiotic Stewardship, Infection Control Programs, and Environmental Cleaning at a Chinese University Hospital</p>

“…40 One study revealed that the incidence of MDRAB was addressed by controlling the inappropriate duration of antimicrobial treatments and the misuse of carbapenems. 41 However, the values of DDD in our study are clearly higher than those reported in Australia and the Netherlands. 21,42 This may be related to the insufficient of administration of antibiotic application.…”

Chlorine disinfection facilitates natural transformation through ROS-mediated oxidative stress

“…S10). This might be associated with the fact that disinfectant itself could also pose direct effects on the cell membrane, as reported in a previous study [53].…”

“…Consequently, the quenching of ROS may eliminate the antibacterial effects of chloramine and free chlorine. Previous studies also show that microbial ROS production potentiates antibacterial effects [52], and that chlorine-based disinfectants cause a ROS-dependent damage mechanism [53]. However, it should be admitted that there is much controversy about whether ROS changes are symptoms or causes of the increased HGT and antimicrobial induced killing of bacteria [36,37].…”

Molecular mechanism of antimicrobial activity of chlorhexidine against carbapenem-resistant Acinetobacter baumannii

“…Reports showed that chlorhexidine have role in ROS elevation to produce its antimicrobial effect [19–21]. Therefore, the reactive oxygen species (ROS) was measured by nitro blue tetrazolium assay (NBT) on a multi-well scanning spectrophotometer (ELISA reader) as per published protocol [22].…”

“…MDA (the secondary product) produce a pink-colored dimeric compound with thiobarbituric acid (TBA), which can be easily quantified using ELISA reader. We have quantified lipid peroxidation as per our published method [22].…”