Bactericidal Effect of Sodium Hypochlorite and Chlorine Dioxide against Mycobacteria and Mycobacterial Biofilm

The highly prescribed antidepressant, citalopram, as one of newly emerging pollutants, has been frequently detected in the aquatic environment. Citalopram oxidation was examined during sodium hypochlorite (NaOCl) and chlorine dioxide (ClO2) chlorination processes since conventional wastewater treatment plants cannot remove citalopram effectively. Citalopram has been demonstrated to form N-nitrosodimethylamine (NDMA) during chlorination in our previous study. Further investigation on NDMA formation kinetics was conducted in the present study. Influences of operational variables (disinfectant dose, pH value) and water matrix on citalopram degradation, as well as NDMA generation, were evaluated. The results indicated high reactivity of citalopram with NaOCl and ClO2. NDMA formation included two stages during CIT oxidation, which were linear related with reaction time. NaOCl was more beneficial to remove CIT, but it caused more NDMA formation. Increasing disinfectant dosage promoted citalopram removal and NDMA formation. However, no consistent correlation was found between citalopram removal and pH. Contrary to the situation of citalopram removal, NDMA generation was enhanced when citalopram was present in actual water matrices, especially in secondary effluent. DMA, as an intermediate of citalopram chlorination, contributed to NDMA formation, but not the only way.

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Bactericidal compounds controlling growth of the plant pathogen pseudomonas syringae pv. actinidiae, which forms biofilms composed of a novel exopolysaccharide

10.26686/wgtn.12597797 ◽

2020 ◽

Author(s):

S Ghods ◽

Ian Sims ◽

MF Moradali ◽

BHA Rehma

Keyword(s):

Pseudomonas Syringae ◽

Chlorine Dioxide ◽

Laser Scanning ◽

Extracellular Polymeric Substances ◽

Virulent Strain ◽

Bactericidal Effect ◽

Cell System ◽

Laser Scanning Microscopy ◽

Base Layer ◽

Confocal Laser

© 2015, American Society for Microbiology. Pseudomonas syringae pv. actinidiae is the major cause of bacterial canker and is a severe threat to kiwifruit production worldwide. Many aspects of the disease caused by P. syringae pv. actinidiae, such as the pathogenicity-relevant formation of a biofilm composed of extracellular polymeric substances (EPSs), are still unknown. Here, a highly virulent strain of P. syringae pv. actinidiae, NZ V-13, was studied with respect to biofilm formation and architecture using a flow cell system combined with confocal laser scanning microscopy. The biofilm formed by P. syringae pv. actinidiae NZ V-13 was heterogeneous, consisting of a thin cellular base layer 5 μm thick and microcolonies with irregular structures. The major component of the EPSs produced by P. syringae pv. actinidiae NZ V-13 bacteria was isolated and identified to be an exopolysaccharide. Extensive compositional and structural analysis showed that rhamnose, fucose, and glucose were the major constituents, present at a ratio of 5:1.5:2. Experimental evidence that P. syringae pv. actinidiae NZ V-13 produces two polysaccharides, a branched α-D-rhamnan with side chains of terminal α-D-Fucf and an α-D-1,4-linked glucan, was obtained. The susceptibility of the cells in biofilms to kasugamycin and chlorine dioxide was assessed. About 64 and 73% of P. syringae pv. actinidiae NZ V-13 cells in biofilms were killed when kasugamycin and chlorine dioxide were used at 5 and 10 ppm, respectively. Kasugamycin inhibited the attachment of P. syringae pv. actinidiae NZ V-13 to solid surfaces at concentrations of 80 and 100 ppm. Kasugamycin was bacteriostatic against P. syringae pv. actinidiae NZ V-13 growth in the planktonic mode, with the MIC being 40 to 60 ppm and a bactericidal effect being found at 100 ppm. Here we studied the formation, architecture, and composition of P. syringae pv. actinidiae biofilms as well as used the biofilm as a model to assess the efficacies of bactericidal compounds.

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Ground and surface water for drinking: a laboratory study on genotoxicity using plant tests

Journal of Public Health Research ◽

10.4081/jphr.2012.e7 ◽

2012 ◽

Vol 1 (1) ◽

pp. 7 ◽

Cited By ~ 3

Author(s):

Donatella Feretti ◽

Elisabetta Ceretti ◽

Bianca Gustavino ◽

Ilaria Zerbini ◽

Claudia Zani ◽

...

Keyword(s):

Drinking Water ◽

Surface Water ◽

Sodium Hypochlorite ◽

Chlorine Dioxide ◽

Molar Ratio ◽

Positive Effects ◽

Genotoxic Potential ◽

Micronucleus Tests ◽

Products Of Reaction ◽

Positive Results

Surface waters are increasingly utilized for drinking water because groundwater sources are often polluted. Several monitoring studies have detected the presence of mutagenicity in drinking water, especially from surface sources due to the reaction of natural organic matter with disinfectant. The study aimed to investigate the genotoxic potential of the products of reaction between humic substances, which are naturally present in surface water, and three disinfectants: chlorine dioxide, sodium hypochlorite and peracetic acid. Commercial humic acids dissolved in distilled water at different total organic carbon (TOC) concentrations were studied in order to simulate natural conditions of both ground water (TOC=2.5 mg/L) and surface water (TOC=7.5 mg/L). These solutions were treated with the biocides at a 1:1 molar ratio of C:disinfectant and tested for genotoxicity using the anaphase chromosomal aberration and micronucleus tests in Allium cepa, and the Vicia faba and Tradescantia micronucleus tests. The tests were carried out after different times and with different modes of exposure, and at 1:1 and 1:10 dilutions of disinfected and undisinfected humic acid solutions. A genotoxic effect was found for sodium hypochlorite in all plant tests, at both TOCs considered, while chlorine dioxide gave positive results only with the A.cepa tests. Some positive effects were also detected for PAA (A.cepa and Tradescantia). No relevant differences were found in samples with different TOC values. The significant increase in all genotoxicity end-points induced by all tested disinfectants indicates that a genotoxic potential is exerted even in the presence of organic substances at similar concentrations to those frequently present in drinking water.

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An Evaluation of Historical Bleaching with Chlorine Dioxide Gas, Sodium Hypochlorite, and Chloramine-T at the Fogg Art Museum

Restaurator International Journal for the Preservation of Library and Archival Material ◽

10.1515/res-2012-0012 ◽

2012 ◽

Vol 33 (3-4) ◽

Cited By ~ 2

Author(s):

Theresa Smith

Keyword(s):

Twentieth Century ◽

Formic Acid ◽

Sodium Hypochlorite ◽

Chlorine Dioxide ◽

Art Museum ◽

Sodium Chlorite ◽

Chlorine Dioxide Gas ◽

Brightness Reversion ◽

Chloramine T

AbstractIn the mid-twentieth century, drawings by Jean-Auguste-Dominique Ingres at the Fogg Art Museum were treated with chemical bleaches such as chlorine dioxide gas, sodium hypochlorite, and chloramine-T. Fifty years later, the darkened condition of the drawings was attributed to bleaching with chlorine dioxide gas. This paper discusses the three methods developed by Rutherford John Gettens to generate chlorine dioxide gas from sodium chlorite, formaldehyde and formic acid, examines the use of these bleaching methods to treat Ingres drawings at the Fogg, and discusses the sodium hypochlorite and chloramine-T bleaching methods also in use at the time. The treatments of two Ingres drawings are compared and evaluated in light of later bleaching studies and the current condition of each drawing. All of these historical bleaching methods, as practiced on the works studied, contributed to the darkening and colour/brightness reversion of drawings.

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Application of ozone ultrafine bubble water for cleaning and sterilizing the dialysis circuit

MATEC Web of Conferences ◽

10.1051/matecconf/201819203034 ◽

2018 ◽

Vol 192 ◽

pp. 03034

Author(s):

Yukiko Nakahara ◽

Kazutoku Miyazaki ◽

Junji Nakao ◽

Shijie Zhu

Keyword(s):

Aqueous Solution ◽

Sodium Hypochlorite ◽

Ozone Concentration ◽

Bactericidal Effect ◽

Water Influence

The dialysis circuit was washed by the ultrafine bubble (UFB) water and ozone UFB water and sodium hypochlorite aqueous solution. The effect of washing time, ozone concentration of UFB water, influence of UFB water on artificial dialysis equipment, etc. were investigated. The cleaning and sterilizing effect of ozone UFB water passed through the filter for artificial dialysis was verified. It was confirmed that there were no colony bacteria in the circuit which was washed by the ozone UFB water for 1 hour. Ozone UFB water has the same bactericidal effect as sodium hypochlorite. As an alternative of sodium hypochlorite, we are expecting its application to the cleaning and sterilization of ozone UFB water for dialysis circuit.

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Extension of Bactericidal Effect of Sodium Hypochlorite into Dentinal Tubules

Journal of Endodontics ◽

10.1016/j.joen.2013.09.045 ◽

2014 ◽

Vol 40 (6) ◽

pp. 825-829 ◽

Cited By ~ 36

Author(s):

Debbie T.S. Wong ◽

Gary S.P. Cheung

Keyword(s):

Sodium Hypochlorite ◽

Bactericidal Effect ◽

Dentinal Tubules

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Bactericidal compounds controlling growth of the plant pathogen pseudomonas syringae pv. actinidiae, which forms biofilms composed of a novel exopolysaccharide

10.26686/wgtn.12597797.v1 ◽

2020 ◽

Author(s):

S Ghods ◽

Ian Sims ◽

MF Moradali ◽

BHA Rehma

Keyword(s):

Pseudomonas Syringae ◽

Chlorine Dioxide ◽

Laser Scanning ◽

Extracellular Polymeric Substances ◽

Virulent Strain ◽

Bactericidal Effect ◽

Cell System ◽

Laser Scanning Microscopy ◽

Base Layer ◽

Confocal Laser

© 2015, American Society for Microbiology. Pseudomonas syringae pv. actinidiae is the major cause of bacterial canker and is a severe threat to kiwifruit production worldwide. Many aspects of the disease caused by P. syringae pv. actinidiae, such as the pathogenicity-relevant formation of a biofilm composed of extracellular polymeric substances (EPSs), are still unknown. Here, a highly virulent strain of P. syringae pv. actinidiae, NZ V-13, was studied with respect to biofilm formation and architecture using a flow cell system combined with confocal laser scanning microscopy. The biofilm formed by P. syringae pv. actinidiae NZ V-13 was heterogeneous, consisting of a thin cellular base layer 5 μm thick and microcolonies with irregular structures. The major component of the EPSs produced by P. syringae pv. actinidiae NZ V-13 bacteria was isolated and identified to be an exopolysaccharide. Extensive compositional and structural analysis showed that rhamnose, fucose, and glucose were the major constituents, present at a ratio of 5:1.5:2. Experimental evidence that P. syringae pv. actinidiae NZ V-13 produces two polysaccharides, a branched α-D-rhamnan with side chains of terminal α-D-Fucf and an α-D-1,4-linked glucan, was obtained. The susceptibility of the cells in biofilms to kasugamycin and chlorine dioxide was assessed. About 64 and 73% of P. syringae pv. actinidiae NZ V-13 cells in biofilms were killed when kasugamycin and chlorine dioxide were used at 5 and 10 ppm, respectively. Kasugamycin inhibited the attachment of P. syringae pv. actinidiae NZ V-13 to solid surfaces at concentrations of 80 and 100 ppm. Kasugamycin was bacteriostatic against P. syringae pv. actinidiae NZ V-13 growth in the planktonic mode, with the MIC being 40 to 60 ppm and a bactericidal effect being found at 100 ppm. Here we studied the formation, architecture, and composition of P. syringae pv. actinidiae biofilms as well as used the biofilm as a model to assess the efficacies of bactericidal compounds.

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Comparative evaluation of human pulp tissue dissolution by different concentrations of chlorine dioxide, calcium hypochlorite and sodium hypochlorite: An in vitro study

Journal of Conservative Dentistry ◽

10.4103/0972-0707.144590 ◽

2014 ◽

Vol 17 (6) ◽

pp. 541 ◽

Cited By ~ 9

Author(s):

Sonali Taneja ◽

Neha Mishra ◽

Shubhra Malik

Keyword(s):

Sodium Hypochlorite ◽

Chlorine Dioxide ◽

Comparative Evaluation ◽

In Vitro Study ◽

Vitro Study ◽

Pulp Tissue ◽

Calcium Hypochlorite

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The Bactericidal Effect of a Combination of Food-Grade Compounds and their Application as Alternative Antibacterial Agents for Food Contact Surfaces

Foods ◽

10.3390/foods9010059 ◽

2020 ◽

Vol 9 (1) ◽

pp. 59 ◽

Cited By ~ 4

Author(s):

Kyung Min Park ◽

Sung-Geon Yoon ◽

Tae-Ho Choi ◽

Hyun Jung Kim ◽

Kee Jai Park ◽

...

Keyword(s):

Sodium Hypochlorite ◽

Salmonella Enteritidis ◽

Antibacterial Agents ◽

Multicomponent System ◽

Viable Cell ◽

Bactericidal Effect ◽

Food Grade ◽

Food Contact ◽

Food Contact Surfaces ◽

Contact Surfaces

Chemical antibacterials are widely used to control microbial growth but have raised concerns about health risks. It is necessary to find alternative, non-toxic antibacterial agents for the inhibition of pathogens in foods or food contact surfaces. To develop a non-toxic and “green” food-grade alternative to chemical sanitizers, we formulated a multicomponent antibacterial mixture containing Rosmarinus officinalis L., Camellia sinensis L., citric acid, and ε-polylysine and evaluated its bactericidal efficacy against Staphylococcus aureus, Escherichia coli, Bacillus cereus, Salmonella Enteritidis, and Listeria monocytogenes on food contact surfaces. A combination of the agents allowed their use at levels lower than were effective when tested individually. At a concentration of 0.25%, the multicomponent mixture reduced viable cell count by more than 5 log CFU/area, with complete inactivation 24 h after treatment. The inhibitory efficacy of the chemical antibacterial agent (sodium hypochlorite, 200 ppm) and the multicomponent antibacterial mixture (0.25%) on utensil surfaces against S. aureus, E. coli, S. Enteritidis, and L. monocytogenes were similar, but the multicomponent system was more effective against B. cereus than sodium hypochlorite, with an immediate 99.999% reduction on knife and plastic basket surfaces, respectively, and within 2 h on cutting board surfaces after treatment. A combination of these food-grade antibacterials could be a useful strategy for inhibition of bacteria on food contact surfaces while allowing use of lower concentrations of its components than are effective individually. This multicomponent food-grade antibacterial mixture may be a suitable “green” alternative to chemical sanitizers.

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