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Molecules (Basel, Switzerland) Sep 2021This study aimed to compare the SARS-CoV-2-inactivation activity and virucidal mechanisms of ozonated water (OW) with those of slightly acidic electrolyzed water (SAEW)...
This study aimed to compare the SARS-CoV-2-inactivation activity and virucidal mechanisms of ozonated water (OW) with those of slightly acidic electrolyzed water (SAEW) and 70% ethanol (EtOH). SARS-CoV-2-inactivation activity was evaluated in a virus solution containing 1%, 20% or 40% fetal bovine serum (FBS) with OW, SAEW or EtOH at a virus-to-test solution ratio of 1:9, 1:19 or 1:99 for a reaction time of 20 s. EtOH showed the strongest virucidal activity, followed by SAEW and OW. Even though EtOH potently inactivated the virus despite the 40% FBS concentration, virus inactivation by OW and SAEW decreased in proportion to the increase in FBS concentration. Nevertheless, OW and SAEW showed potent virucidal activity with 40% FBS at a virus-to-test solution ratio of 1:99. Real-time PCR targeting the viral genome revealed that cycle threshold values in the OW and SAEW groups were significantly higher than those in the control group, suggesting that OW and SAEW disrupted the viral genome. Western blotting analysis targeting the recombinant viral spike protein S1 subunit showed a change in the specific band into a ladder upon treatment with OW and SAEW. OW and SAEW may cause conformational changes in the S1 subunit of the SARS-CoV-2 spike protein.
Topics: COVID-19; Disinfectants; Disinfection; Ethanol; Humans; Ozone; SARS-CoV-2
PubMed: 34576934
DOI: 10.3390/molecules26185465 -
Water Research Oct 2021Pool water is continuously circulated and reused after an extensive treatment including disinfection by chlorination, ozonation or UV treatment. In Germany, these...
Pool water is continuously circulated and reused after an extensive treatment including disinfection by chlorination, ozonation or UV treatment. In Germany, these methods are regulated by DIN standard 19643. Recently, the DIN standard has been extended by a new disinfection method using hypobromous acid as disinfectant formed by introducing ozone into water with naturally or artificially high bromide content during water treatment. In this study, we tested the disinfection efficacy of the ozone-bromine treatment in comparison to hypochlorous acid in a flow-through test rig using the bacterial indicator strains Escherichia coli, Enterococcus faecium, Pseudomonas aeruginosa, and Staphylococcus aureus and the viral indicators phage MS2 and phage PRD1. Furthermore, the formation of disinfection by-products and their potential toxic effects were investigated in eight pool water samples using different disinfection methods including the ozone-bromine treatment. Our results show that the efficacy of hypobromous acid, depending on its concentration and the tested organism, is comparable to that of hypochlorous acid. Hypobromous acid was effective against five of six tested indicator organisms. However, using Pseudomonas aeruginosa and drinking water as test water, both tested disinfectants (0.6 mg L as Cl hypobromous acid as well as 0.3 mg L as Cl hypochlorous acid) did not achieve a reduction of four log levels within 30 s, as required by DIN 19643. The formation of brominated disinfection by-products depends primarily on the bromide concentration of the filling water, with the treatment method having a smaller effect. The eight pool water samples did not show critical values in vitro for acute cytotoxicity or genotoxicity in the applied assays. In real pool water samples, the acute toxicological potential was not higher than for conventional disinfection methods. However, for a final assessment of toxicity, all single substance toxicities of known DBPs present in pool water treated by the ozone-bromine treatment have to be analyzed additionally.
Topics: Bromine; Chlorine; Disinfectants; Disinfection; Halogenation; Ozone; Water; Water Pollutants, Chemical; Water Purification
PubMed: 34543973
DOI: 10.1016/j.watres.2021.117648 -
Water Research Oct 2021The epidemic of COVID-19 has aroused people's particular attention to biosafety. A growing number of disinfection products have been consumed during this period.... (Review)
Review
The epidemic of COVID-19 has aroused people's particular attention to biosafety. A growing number of disinfection products have been consumed during this period. However, the flaw of disinfection has not received enough attention, especially in water treatment processes. While cutting down the quantity of microorganisms, disinfection processes exert a considerable selection effect on bacteria and thus reshape the microbial community structure to a great extent, causing the problem of disinfection-residual-bacteria (DRB). These systematic and profound changes could lead to the shift in regrowth potential, bio fouling potential, as well as antibiotic resistance level and might cause a series of potential risks. In this review, we collected and summarized the data from the literature in recent 10 years about the microbial community structure shifting of natural water or wastewater in full-scale treatment plants caused by disinfection. Based on these data, typical DRB with the most reporting frequency after disinfection by chlorine-containing disinfectants, ozone disinfection, and ultraviolet disinfection were identified and summarized, which were the bacteria with a relative abundance of over 5% in the residual bacteria community and the bacteria with an increasing rate of relative abundance over 100% after disinfection. Furthermore, the phylogenic relationship and potential risks of these typical DRB were also analyzed. Twelve out of fifteen typical DRB genera contain pathogenic strains, and many were reported of great secretion ability. Pseudomonas and Acinetobacter possess multiple disinfection resistance and could be considered as model bacteria in future studies of disinfection. We also discussed the growth, secretion, and antibiotic resistance characteristics of DRB, as well as possible control strategies. The DRB phenomenon is not limited to water treatment but also exists in the air and solid disinfection processes, which need more attention and more profound research, especially in the period of COVID-19.
Topics: Bacteria; COVID-19; Disinfection; Humans; Microbiota; SARS-CoV-2
PubMed: 34500181
DOI: 10.1016/j.watres.2021.117606 -
MethodsX 2021Hydrogen peroxide is commonly used as a sterilizing agent for medical devices and its use has recently been extended to N95 masks during PPE shortages as a result of the...
Hydrogen peroxide is commonly used as a sterilizing agent for medical devices and its use has recently been extended to N95 masks during PPE shortages as a result of the COVID-19 pandemic. The hydrogen peroxide remaining on the masks after sterilization could potentially pose a health hazard to the mask users. In the present study a colorimetric method was optimized for the determination of hydrogen peroxide on N95 masks following chemical sanitizations. The developed analytical method demonstrated an overall recovery of 98% ± 7%. The limit of detection ranged from 0.16 to 0.25 mg/mask, depending on the type of mask. The expanded measurement uncertainty was 13% (at a 95% confidence interval). The sanitization process itself introduced a significant variation in hydrogen peroxide load between masks. The ozone used in the sanitization process had no significant impact on analytical performance. Stamped and printed marks on the mask surfaces could induce biased readings. Hydrogen peroxide decomposes quickly on the mask surfaces so timing of analysis is an important factor in method standardization.•The validation data demonstrated that the in-house method is reliable and fit for the intended purpose, offering a sensitive, simple, rapid, and inexpensive method of residue monitoring.
PubMed: 34434883
DOI: 10.1016/j.mex.2021.101485 -
Bactericidal activity of three different antiseptic ophthalmic preparations as surgical prophylaxis.Graefe's Archive For Clinical and... Jan 2022In the era of antibiotic resistance, there is an increased interest in antiseptic solutions that might represent a reliable option for ocular surface disinfection. The...
PURPOSE
In the era of antibiotic resistance, there is an increased interest in antiseptic solutions that might represent a reliable option for ocular surface disinfection. The objective of this study is to compare for the first time three different antiseptic ophthalmic preparations to assess their in vitro antimicrobial activity.
METHODS
The antiseptic activity of three commercial ophthalmic solutions, IODIM (povidone-iodine 0.6% in hyaluronic acid vehicle-Medivis, Catania, Italy), OZODROP (nanoemulsion with ozonated oil-concentration not specified-FBVision, Ophthalmic Pharmaceuticals, Rome, Italy), and DROPSEPT (chlorhexidine 0.02% and vitamin E 0.5% Tocopherol Polyethylene Glycol 1000 Succinate-TPGS, Sooft Italia, Montegiorgio, Italy), was tested in vitro on six reference strains by time-killing assays. Viable cells were evaluated after 1, 15, 30 min; 2, 6, and 24 h exposure by seeding 100 µl of the suspension (or appropriate dilutions) on LB agar or Sabouraud-dextrose agar. All plates were incubated at 37 °C for 24 h and evaluated by manually counting the colonies.
RESULTS
IODIM solution showed a very rapid microbicidal activity: the number of viable cells for all the tested strains was under the detection limit (less than 10 CFU/ml) already after 1 min exposure, and this result was maintained at every incubation time. The rapid antimicrobial activity of povidone-iodine was not replicated when testing the other two antiseptics.
CONCLUSIONS
The study reports the great efficacy in reducing bacterial load in a very short time of povidone-iodine 0.6% compared with other antiseptic preparations.
Topics: Anti-Infective Agents, Local; Chlorhexidine; Disinfection; Ophthalmic Solutions; Povidone-Iodine
PubMed: 34427741
DOI: 10.1007/s00417-021-05361-3 -
Environment International Dec 2021Pre-ozonation can reduce the formation of disinfection byproducts (DBPs) and related adverse effects during subsequent chlorination, but the change of each molecular...
Understanding the influence of pre-ozonation on the formation of disinfection byproducts and cytotoxicity during post-chlorination of natural organic matter: UV absorbance and electron-donating-moiety of molecular weight fractions.
Pre-ozonation can reduce the formation of disinfection byproducts (DBPs) and related adverse effects during subsequent chlorination, but the change of each molecular weight (MW) fraction during each step of combined pre-ozonation and post-chlorination has not been well illustrated. In this study, it was investigated in terms of electron-donating-moieties (EDMs) and UVA for a representative natural organic matter from Suwanee river (SRNOM). Pre-ozonation suppressed the post-chlorination of SRNOM through oxidation of almost all EDMs (>85%) and UVA (>90%) in high MW fractions (HMW, >3.2 kDa) and moderate EDMs (43%) and UVA (72%) in medium MW fractions (MMW, 1.0-3.2 kDa). Furthermore, pre-ozonation led to comparable abatements of EDMs and UVA for HMW fractions, but lower abatement of EDMs than UVA for MMW fractions. However, when t-BuOH was used as an OH-quencher, pre-ozonation led to a few instances in which there were higher abatements of EDMs than UVA for the MMW fraction. These findings suggested that the HMW fraction dominantly underwent ring-cleavage of phenols via O- or OH-oxidation. Differently, the MMW fraction underwent ring-cleavage of phenols and quinones-formation via O-oxidation, but occasionally underwent hydroxylation and hydro-phenol formation via OH-oxidation. Because of forehand elimination of reactive moieties (e.g. EDMs), pre-ozonation obviously inhibited the formation of representative DBPs (67%-84% inhibition), total organic chloride (51% inhibition) and cytotoxicity (31% inhibition), but may have promoted the formation of carbonyl-DBPs (trichloroacetone and chloral hydrate). When compared with UVA, EDMs would better for surrogate of DBPs formation. EDM abatement surrogated the formation of total organic chlorine (TOCl) and cytotoxicity following a two-stage phase, possibly because the speciation of DBPs and transformation products varied with the abatement of EDMs.
Topics: Disinfectants; Disinfection; Electrons; Halogenation; Molecular Weight; Ozone; Water Pollutants, Chemical; Water Purification
PubMed: 34332302
DOI: 10.1016/j.envint.2021.106793 -
Environmental Science and Pollution... Dec 2021In recent years, the sanitization of environments, devices, and objects has become mandatory to improve human and environmental safety, in addition to individual...
In recent years, the sanitization of environments, devices, and objects has become mandatory to improve human and environmental safety, in addition to individual protection and prevention measures. International studies considered ozone one of the most useful and easy sanitization methods for indoor environments, especially hospital environments that require adequate levels of disinfection. The purpose of this work was to evaluate the microclimate influence on sanitizing procedure for indoor settings with ozone, to prevent infections and ensure the safe use of the environments. The concentration of ozone was measured during sanitization treatment and estimation of microorganisms' survival on the air and different contaminated plates after the sanitization operations were performed. The results demonstrated a significant reduction in the microbial count that always fell below the threshold value in different conditions of distance, temperature, and relative humidity.
Topics: Air Pollution, Indoor; Disinfection; Hospitals; Humans; Microclimate; Ozone; Workplace
PubMed: 34318416
DOI: 10.1007/s11356-021-15457-2 -
PloS One 2021Influenza and RSV are human viruses responsible for outbreaks in hospitals, long-term care facilities and nursing homes. The present study assessed an air treatment...
Influenza and RSV are human viruses responsible for outbreaks in hospitals, long-term care facilities and nursing homes. The present study assessed an air treatment using ozone at two relative humidity conditions (RHs) in order to reduce the infectivity of airborne influenza. Bovine pulmonary surfactant (BPS) and synthetic tracheal mucus (STM) were used as aerosols protectants to better reflect the human aerosol composition. Residual ozone concentration inside the aerosol chamber was also measured. RSV's sensitivity resulted in testing its resistance to aerosolization and sampling processes instead of ozone exposure. The results showed that without supplement and with STM, a reduction in influenza A infectivity of four orders of magnitude was obtained with an exposure to 1.70 ± 0.19 ppm of ozone at 76% RH for 80 min. Consequently, ozone could be considered as a virucidal disinfectant for airborne influenza A. RSV did not withstand the aerosolization and sampling processes required for the use of the experimental setup. Therefore, ozone exposure could not be performed for this virus. Nonetheless, this study provides great insight for the efficacy of ozone as an air treatment for the control of nosocomial influenza A outbreaks.
Topics: Aerosols; Air Microbiology; Cross Infection; Disinfection; Humans; Influenza A virus; Influenza, Human; Ozone; Real-Time Polymerase Chain Reaction; Respiratory Syncytial Virus Infections; Respiratory Syncytial Viruses; Virus Inactivation
PubMed: 34252093
DOI: 10.1371/journal.pone.0253022 -
Materials Today. Proceedings 2023The current COVID-19 pandemic has increased the use of alcohol based hand sanitisers globally. These available alcohol based sanitisers cannot provide an antibacterial...
The current COVID-19 pandemic has increased the use of alcohol based hand sanitisers globally. These available alcohol based sanitisers cannot provide an antibacterial effect for an extended period of time, after the evaporation of ethanol. Hence, the need for a sanitiser with an anti-microbial activity combined with a long lasting effect is the need of the hour. In this study, we report the synthesis of a long lasting sanitiser from ozonated omega 9 fatty acid esters in an ethanolic medium. The formed vesicles made of the fatty acids have been characterized by DLS, Zeta potential, and time resolved fluorescence anisotropy studies. Ethanol although, provides an antibacterial effect, the effect is more pronounced in our prepared formulation owing to its high peroxide value that generates additional oxidative stress. Finally, this additional antimicrobial effect will have relevance in the current COVID-19 scenario in providing a long lasting hand sanitiser.
PubMed: 34178606
DOI: 10.1016/j.matpr.2021.05.623 -
Medycyna Pracy Nov 2021The COVID-19 pandemic is currently one of the major global health and economic challenges. An efficient method for reducing the transmission of the virus is a still...
The COVID-19 pandemic is currently one of the major global health and economic challenges. An efficient method for reducing the transmission of the virus is a still unmet medical need. Existing experimental data have shown that coronavirus survival is negatively impacted by ozone, high temperature, and low humidity. Therefore, it is feasible to use area ozonation in pharmacies - the front line of the healthcare system. Nevertheless, further work is needed to evaluate the effectiveness of ozone disinfection to reduce the transmission of this virus in pharmacies, hospitals, and other public environments. Med Pr. 2021;72(5):529-34.
Topics: COVID-19; Disinfection; Humans; Ozone; Pandemics; Pharmacies; SARS-CoV-2
PubMed: 34140707
DOI: 10.13075/mp.5893.01091