Effect of naturally isolated hydroquinone in disturbing the cell membrane integrity of Pseudomonas aeruginosa MTCC 741 and Staphylococcus aureus MTCC 740

Abstract

Nosocomial pathogens cause various health problems in human and many novel drugs are under investigation to combat the pathogens. The present study explains the naturally derived hydroquinone possible mode of action against Pseudomonas aeruginosa MTCC 741 and Staphylococcus aureus MTCC 740. Time kill studies, cell viability assays, membrane potential assays, and potassium release assays were carried out to study the mode of action. Time kill studies revealed the rapid death of bacterial pathogens exposed to 4X MIC (Minimum inhibitory concentration) of the hydroquinone. Cell viability assay results showed that nearly half of the cell destruction of test pathogens occurred within one hour. Transmission electron microscopic (TEM) observations revealed the disruption of the cell membrane, which caused severe ultrastructural changes in both test pathogens. Hydroquinone dissipated the membrane potential of test pathogens, as confirmed by the depolarization of membrane potential, increases in permeability and leakage of intracellular potassium ions. At the concentration of 2X MIC hydroquinone in 5 min, about 91.41% and 84.85% potassium ions were released from P. aeruginosa MTCC 741 and S. aureus MTCC 740, respectively. This is the first report on the mode of action of naturally derived hydroquinone against clinical pathogens.

Hydroquinones Including Tetrachlorohydroquinone Inhibit Candida albicans Biofilm Formation by Repressing Hyphae-Related Genes

“…Hydroquinone (HQ) and its derivatives have been reported to exhibit antimicrobial activities against drug-resistant Staphylococcus aureus and Pseudomonas aeruginosa ( 11 – 13 ). However, the mechanisms responsible have not been determined, and little is known of their antibiofilm activities.…”

A Cyclic Disulfide Diastereomer From Bioactive Fraction of Bruguiera gymnorhiza Shows Anti–Pseudomonas aeruginosa Activity

“… Girard et al (2019) and Wu et al (2016) studied the viability of E. coli and S. aureus with essential oils and hydroquinic acid. Similarly, the effect of naturally isolated hydroquinone against cell membrane integrity of P. aeruginosa and S. aureus strains was evaluated by flow cytometry, and more than 46% inhibition of P. aeruginosa and S. aureus cells after 2 h incubation was reported ( Jeyanthi et al, 2021 ). Likewise, in the current study, the cell viability assay of P. aeruginosa was carried out at two concentration levels (1x MIC and 2x MIC), which shows concentration-dependent reduction of the cell population within 4 h. On the other hand, change in morphology and destruction of the cell membrane is demonstrated at the same MIC concentration by SEM analysis which shows irregularly shrunken cells and deformed, damaged membranes after treatment with BG138 for 4 h. Consistent with these results, Vernonia cinerea extract against P. aeruginosa ( Latha et al, 2010 ) and a semi-synthetic antimicrobial compound such as “3-(p-chlorophenyl)thio citronellal” show morphological changes in Listeria monocytogenes and P. fluorescens after exposure ( Goldbeck et al, 2014 ).…”

“…The percentage of PI-stained cells was determined using BD FACS Chorus TM application software. PI fluorescing cells (P8) were gated as dead or membrane-damaged cells, while untreated cells (P7) were gated as live cells ( Yasir et al, 2019 ; Jeyanthi et al, 2021 ).…”

Combinations of Peptide-Protein Extracts from Native Probiotics Suppress the Growth of Multidrug-Resistant Staphylococcus aureus and Citrobacter freundii via Membrane Perturbation and Ultrastructural Changes

“…The diseases associated with multidrug-resistant microorganisms such as Staphylococcus aureus, Salmonella spp., Clostridium perfringens, E. coli spp., and other Enterobacteriaceae, remain a public health concern [ 1 , 2 ]. S. aureus, a Gram-positive and cocci-shaped bacterium, is a pathogen involved in nosocomial and community-acquired infections, including skin tissue infection and pneumonia [ 3 ]. Several strains exhibit a multidrug-resistant phenotype, survive, and grow in a wide range of environmental conditions, having been detected in vegetables, fruits, meat, and bakery products, which impose a high risk for human health [ 4 ].…”