In vitro antimicrobial activity of three new generation disinfectants

Purpose: To determine the efficacies of three commercially available new generation disinfectants against some bacteria and yeast.Methods: Three commercially available new generation disinfectant (0.2 % chlorine dioxide, 0.3 % chlorine dioxide and 50 % hydrogen peroxide-stabilized by colloidal silver) were screened for their antimicrobial activity against Escherichia coli ATCC 25922, Klebsiella pneumonia RSKK 574, Pseudomonas aeruginosa ATCC 9027, Enterococcus faecalis ATCC 29212, Staphylococcus aureus ATCC 25923, S. aureus ATCC 43300 (methicillin resistant), S. epidermidis ATCC 12228 (non-biofilm forming), S. epidermidis ATCC 35948 (biofilm forming) and Candida albicans ATCC 10231. Quantitative suspension test was used to determine the efficacies of the disinfectants at contact times of 1, 3 and 5 min.Results: All of the new generation disinfectants were effective against test microorganisms at all test contact times.Conclusions: The findings indicate that the tested new generation disinfectants may be useful for routine disinfection purposes.Keywords: Antimicrobial activity, New generation disinfectants, Routine disinfectio

Pharmacological assessment of Co3O4, CuO, NiO and ZnO nanoparticles via antibacterial, anti-biofilm and anti-quorum sensing activities

Infectious diseases have risen dramatically as a result of the resistance of many common antibiotics. Nanotechnology provides a new avenue of investigation for the development of antimicrobial agents that effectively combat infection. The combined effects of metal-based nanoparticles (NPs) are known to have intense antibacterial activities. However, a comprehensive analysis of some NPs regarding these activities is still unavailable. This study uses the aqueous chemical growth method to synthesize Co3O4, CuO, NiO and ZnO NPs. The prepared materials were characterized by scanning electron microscopy, transmission electron microscopy and X-ray diffraction techniques. The antibacterial activities of NPs were tested against Gram-positive and Gram-negative bacteria using the microdilution method, such as the minimum inhibitory concentration (MIC) method. The best MIC value among all the metal oxide NPs was 0.63 against Staphylococcus epidermidis ATCC12228 through ZnO NPs. The other metal oxide NPs also showed satisfactory MIC values against different test bacteria. In addition, the biofilm inhibition and antiquorum sensing activities of NPs were also examined. The present study presents a novel approach for the relative analysis of metal-based NPs in antimicrobial studies, demonstrating their potential for bacteria removal from water and wastewater. HIGHLIGHTS Metal oxide nanoparticles were synthesized using the chemical growth method.; The prepared materials were characterized by scanning electron microscopy, transmission electron microscopy and X-ray diffraction techniques.; The antimicrobial activity was tested against Gram-positive and Gram-negative bacteria.