RESUMEN
The inability to integrate detection and disinfection hindered building a unified pathogen monitoring platform, risking secondary contamination. Herein, a novel "four - in - one" platform for monitoring foodborne Listeria monocytogenes (L. monocytogenes) was presented. The magnetic daptomycin - functionalized Fe3O4 (Dap/Fe3O4) could selectively bind to L. monocytogenes, enhancing detection accuracy. The separated bacteria were captured by aptamers - functionalized Fe - doped - silica nanoparticles (Apt/Fe@SiNPs) for tri - mode detection. Besides fluorescence, the Apt/Fe@SiNPs converted 3,3',5,5' - tetramethylbenzidine (TMB) to oxidized TMB (oxTMB) via peroxidase activity, allowing colorimetric and subsequent photothermal detection upon irradiation, as low as 2.06 CFU/mL. Magnetic - induced aggregation of Apt/Fe@SiNPs generated toxic hydroxyl radicals around L. monocytogenes, achieving â¼99.6% disinfection. Furthermore, the biofilm of L. monocytogenes was effectively inhibited by the action of hydroxyl radicals. The platform might offer a promising prospect to control L. monocytogenes in food industries.
Asunto(s)
Listeria monocytogenes , Listeria monocytogenes/efectos de los fármacos , Listeria monocytogenes/crecimiento & desarrollo , Desinfección/instrumentación , Desinfección/métodos , Nanopartículas/química , ColorimetríaRESUMEN
Photocatalytic disinfection is an eco-friendly strategy for countering bacterial pollution in aquatic environments. Numerous strategies have been devised to facilitate the generation of reactive oxygen species (ROS) within photocatalysts, ultimately leading to the eradication of bacteria. However, the significance of the physical morphology of photocatalysts in the context of sterilization is frequently obscured, and the progress in the development of physical-chemical synergistic sterilization photocatalysts has been relatively limited. Herein, graphitic carbon nitride (g-C3N4) is chemically protonated to expose more sharp edges. PL fluorescence and EIS results indicate that the protonation can accelerate photogenerated carrier separation and enhance ROS production. Meanwhile, the sharp edges on the protonated g-C3N4 facilitate the physical disruption of cell walls for further promoting oxidative damage. Protonated C3N4 demonstrated superior bactericidal performance than that of pristine g-C3N4, effectively eliminating Escherichia coli within 40 minutes under irradiation. This work highlights the significance of incorporating physical and chemical synergies in photocatalyst design to enhance the disinfection efficiency of photocatalysis.
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Desinfección , Nitrilos , Nitrilos/química , Desinfección/métodos , Catálisis , Escherichia coli/efectos de los fármacos , Especies Reactivas de Oxígeno , Grafito/química , Esterilización/métodos , Compuestos de Nitrógeno/químicaRESUMEN
Because of the recent widespread usage of antibiotics, the acquisition and dissemination of antibiotic-resistance genes (ARGs) were prevalent in the majority of habitats. Generally, the biological wastewater treatment processes used in wastewater treatment plants have a limited efficiencies of antibiotics resistant bacteria (ARB) disinfection and ARGs degradation and even promote the proliferation of ARGs. Problematically, ARB and ARGs in effluent pose potential risks if they are not further treated. Photocatalytic oxidation is considered a promising disinfection technology, where the photocatalytic process generates many free radicals that enhance the interaction between light and deoxyribonucleic acid (DNA) for ARB elimination and subsequent degradation of ARGs. This review aims to illustrate the progress of photocatalytic oxidation technology for removing antibiotics resistant (AR) from wastewater in recent years. We discuss the sources and transfer of ARGs in wastewater. The overall removal efficiencies of ultraviolet radiation (UV)/chlorination, UV/ozone, UV/H2O2, and UV/sulfate-radical based system for ARB and ARGs, as well as the experimental parameters and removal mechanisms, are systematically discussed. The contribution of photocatalytic materials based on TiO2 and g-C3N4 to the inactivation of ARB and degradation of ARGs is highlighted, producing many free radicals to attack ARB and ARGs while effectively limiting the horizontal gene transfer (HGT) in wastewater. Finally, based on the reviewed studies, future research directions are proposed to realize specific photocatalytic oxidation technology applications and overcome current challenges.
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Eliminación de Residuos Líquidos , Aguas Residuales , Aguas Residuales/química , Eliminación de Residuos Líquidos/métodos , Bacterias , Desinfección/métodos , Farmacorresistencia Bacteriana/genética , Rayos Ultravioleta , Purificación del Agua/métodosRESUMEN
Epidemiological studies show that the care of patients in rooms with a previous stay by a person with evidence of multi-resistant pathogens (MRP) is associated with an increased risk of these pathogens occurring. The question therefore regularly arises as to whether MRP also exhibit resistance to the disinfectants used. To date, there are no standardised definitions for "resistance" to disinfectants. However, disinfectants authorised on the market are also effective against multi-resistant pathogens and the failure of efficient disinfection is mainly caused by application errors (insufficient cleaning, incomplete wetting, incorrect application concentration or exposure time etc.). The effectiveness of disinfectants depends on a variety of environmental factors (especially accompanying contamination). A reduced sensitivity to disinfectants can occur in individual isolates due to selection under sub-inhibitory concentrations of disinfectants. Resistance mechanisms to antibiotics do not mediate cross-resistance to disinfectants, but a change in the permeability of bacterial cells can influence sensitivity to disinfectants and antibiotics. In general, the success of routine disinfection can be improved by suitable process controls and contribute to reducing the transmission of MRP.
Asunto(s)
Desinfectantes , Desinfectantes/farmacología , Humanos , Desinfección/métodos , Infección Hospitalaria/prevención & control , Infección Hospitalaria/microbiología , Farmacorresistencia Bacteriana MúltipleRESUMEN
Paint is a versatile material that can be used to coat surfaces for which routine disinfection practices may be lacking. EPA-registered copper-containing supplemental residual antimicrobial paints could be used to reduce the bioburden on often-neglected surfaces. An interventional study was conducted by painting the walls of a preschool restroom and metal locker surfaces in two hospital locker rooms with a copper-containing antimicrobial paint to evaluate the potential for bioburden reduction compared to a non-copper-containing control paint. The antimicrobial paint reduced the bioburden on the preschool restroom walls by 57% and on lockers in one locker room by 63% compared to the control paint; no significant difference was observed between the two paint types in the second locker room. The upper quartile bacterial counts, which drive the overall risk by increasing exposure to pathogens, also exhibited 63% and 47% reductions for the antimicrobial paint compared to the control paint in the preschool restroom and the first locker room, respectively. Because detectible levels of bioburden are found on large-area surfaces such as walls and lockers, surfaces painted with copper-containing paints may make large-area surfaces that are prone to contamination safer in a way that is practical and economical.
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Antiinfecciosos , Desinfección , Pintura , Pintura/análisis , Desinfección/métodos , Antiinfecciosos/farmacología , Humanos , Cobre/farmacología , Propiedades de SuperficieRESUMEN
Bacterial spores in materials and equipment pose significant biosecurity risks, making effective disinfection crucial. This study evaluated Ortho-phthalaldehyde (OPA) and a quaternary ammonia-glutaraldehyde solution (AG) for inactivating spores of Bacillus thuringiensis (BT), B. cereus (BC), and two strains of B. velezensis (BV1 and BV2). Spores of BV1 and BT were treated with 22.5 mg/m3 OPA by dry fumigation or 1 mg/mL AG by spray for 20 min, according to the manufacturer's recommendation. As no sporicidal effect was observed, OPA was tested at 112.5 mg/m3 for 40 min, showing effectiveness for BT but not for BV1. Minimum bactericidal concentration (MBC) tests revealed higher MBC values for glutaraldehyde, prompting an overnight test with 112.5 mg/m3 OPA by dry fumigation and 50 mg/mL AG by spray, using formaldehyde as a control. AG reduced all Bacillus strains, but with limited sporicidal effect. OPA was sporicidal for BT and BV1 but not for BC and BV2, indicating a strain-dependent effect. Formaldehyde performed better overall but did not completely inactivate BV2 spores. Our findings suggest that OPA and AG have potential as formaldehyde replacements in wet disinfection procedures.
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Bacillus thuringiensis , Bacillus , Desinfectantes , Glutaral , Esporas Bacterianas , Desinfectantes/farmacología , Esporas Bacterianas/efectos de los fármacos , Bacillus/efectos de los fármacos , Bacillus/fisiología , Glutaral/farmacología , Bacillus thuringiensis/efectos de los fármacos , Bacillus thuringiensis/fisiología , Pruebas de Sensibilidad Microbiana , o-Ftalaldehído/farmacología , Bacillus cereus/efectos de los fármacos , Viabilidad Microbiana/efectos de los fármacos , Desinfección/métodosRESUMEN
Selenium nanoparticles (SeNPs) are used in several sectors as antitumor, antimicrobial, and environmental adsorbents. Thus, the present research objective was the production of bacterial-SeNPs as an active and environmentally-friendly antibacterial and adsorbent agents and application into novel nanocomposite filter. From a total of 25 samples (soil, wastewater, and water) obtained from different locations in Egypt, 60 selenium-resistant bacterial isolates were obtained (on a mineral salt medium supplemented with selenium ions). After screening (based on the conversion of selenium from ionic form to nanoform), a superior bacterial isolate for SeNPs formation was obtained and molecular identified as Bacillus pumilus isolate OR431753. The high yield of SeNPs was noted after optimization (glucose as carbon source, pH 9 at 30 °C). The produced SeNPs were characterized as approximately 15 nm-diameter spherical nanoparticles, in addition to the presence of organic substances around these particles like polysaccharides and aromatic amines (protein residues). Also, they have antibacterial activity increased after formation of nanocomposite with nano-chitosan (SeNPs/NCh) against several pathogens. The antibacterial activity (expressed as a diameter of the inhibitory zone) averaged between 2.1 and 4.3, 2.7 and 4.8 cm for SeNPs and SeNPs/NCh, respectively compared with 1.1 to 1.8 cm for Amoxicillin. The produced nanoselenium/chitosan was used as a biofilter to remove mercury (Hg) and AgNPs as model chemicals with serious toxicity and potential pollutant for water bodies in many industries. The new SeNPs/NCh biofilter has proven highly effective in individually removing mercury and AgNPs from their synthetic wastewaters, with an efficiency of up to 99%. Moreover, the removal efficiency of AgNPs stabilized at 99% after treating them with the syringe filter-Se nanocomposite for 4 cycles of treatment (5 min each).
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Biodegradación Ambiental , Mercurio , Nanocompuestos , Selenio , Plata , Aguas Residuales , Purificación del Agua , Aguas Residuales/química , Nanocompuestos/química , Selenio/química , Mercurio/química , Mercurio/aislamiento & purificación , Purificación del Agua/métodos , Plata/química , Contaminantes Químicos del Agua/química , Nanopartículas del Metal/química , Antibacterianos/farmacología , Antibacterianos/química , Desinfección/métodos , Filtración/métodos , Bacillus/metabolismo , Bacillus/efectos de los fármacos , Quitosano/química , Quitosano/farmacologíaRESUMEN
AIMS: The aim of this work was to evaluate the efficacy of an organosilicon-based, commercially available antimicrobial formulation in the My-shield® product line against bacterial surface contamination. METHODS AND RESULTS: The antimicrobial product was tested in vitro for its long-term persistence on surfaces and effectiveness against Staphylococcus aureus biofilms in comparison to 70% ethanol and 0.1% or 0.6% sodium hypochlorite. Field testing was also conducted over 6 weeks at a university athletic facility. In vitro studies demonstrated the log reductions achieved by the test product, 70% ethanol, and 0.1% sodium hypochlorite were 3.6, 3.1, and 3.2, respectively. The test product persisted on surfaces after washing and scrubbing, and pre-treatment with this product prevented S. aureus surface colonization for up to 30 days. In comparison, pre-treatment with 70% ethanol or 0.6% sodium hypochlorite was not protective against S. aureus biofilm formation after seven days. The field test demonstrated that weekly applications of the test product were more effective at reducing surface bacterial load than daily applications of a control product. CONCLUSIONS: The test product conferred greater long-term protection against bacterial growth and biofilm formation by S. aureus than ethanol and sodium hypochlorite. Even with less frequent applications, the test product maintained a high level of antimicrobial activity.
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Biopelículas , Desinfectantes , Hipoclorito de Sodio , Staphylococcus aureus , Biopelículas/efectos de los fármacos , Desinfectantes/farmacología , Staphylococcus aureus/efectos de los fármacos , Hipoclorito de Sodio/farmacología , Etanol/farmacología , Desinfección/métodosRESUMEN
Genome-resolved insights into the structure and function of the drinking water microbiome can advance the effective management of drinking water quality. To enable this, we constructed and curated thousands of metagenome-assembled and isolate genomes from drinking water distribution systems globally to develop a Drinking Water Genome Catalog (DWGC). The current DWGC disproportionately represents disinfected drinking water systems due to a paucity of metagenomes from nondisinfected systems. Using the DWGC, we identify core genera of the drinking water microbiome including a genus (UBA4765) within the order Rhizobiales that is frequently detected and highly abundant in disinfected drinking water systems. We demonstrate that this genus has been widely detected but incorrectly classified in previous amplicon sequencing-based investigations of the drinking water microbiome. Further, we show that a single genome variant (genomovar) within this genus is detected in 75% of drinking water systems included in this study. We propose a name for this uncultured bacterium as "Raskinella chloraquaticus" and describe the genus as "Raskinella" (endorsed by SeqCode). Metabolic annotation and modeling-based predictions indicate that this bacterium is capable of necrotrophic growth, is able to metabolize halogenated compounds, proliferates in a biofilm-based environment, and shows clear indications of disinfection-mediated selection.
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Agua Potable , Agua Potable/microbiología , Desinfección , Bacterias/genética , Microbiota , Genoma Bacteriano , MetagenomaRESUMEN
To systematize published laboratory methods to inactivate Mycobacterium tuberculosis (MTB) and to describe their effectiveness. We carried out a review of the scientific literature to identify the publications that reported methods for the inactivation of MTB, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses recommendations. The search addressed inactivation methodologies used in Public health laboratories for the treatment of biological material and only included studies reporting the efficacy of the method. The database used were PubMed (National Library of Medicine) and LILACS (Latin American and Caribbean Literature in Health Sciences). We evaluated the quality of the studies with the JBI (Joanna Briggs Institute) Critical Instrument Appraisal Checklist. We included 14 publications meeting the established inclusion and exclusion criteria. These 14 studies actually described a total of 35 inactivation methods. Most of them combined heat treatment with some chemical or enzymatic agent, and there were very few applying a single strategy. Twenty-four (68.57%) methods demonstrated significant efficacy in inactivating MTB. The systematic review identified 35 methods of inactivation of MTB, published in 14 studies. Most of the methods combined physical treatment techniques, especially heat, with chemical and/or enzymatic treatment techniques, obtaining mostly good results in preventing the reproduction of the microorganism. PROSPERO (International Prospective Register of Ongoing Systematic Reviews) (Code CRD42024503621).
Asunto(s)
Mycobacterium tuberculosis , Mycobacterium tuberculosis/efectos de los fármacos , Humanos , Tuberculosis/microbiología , Tuberculosis/prevención & control , Viabilidad Microbiana , Desinfección/métodosRESUMEN
Chlorine dioxide (ClO2) is a strong oxidizing agent and an efficient disinfectant. Due to its broad-spectrum bactericidal properties, good inactivation effect on the vast majority of bacteria and pathogenic microorganisms, low resistance to drugs, and low generation of halogenated by-products, chlorine dioxide is widely used in fields such as water purification, food safety, medical and public health, and living environment. This review introduced the properties and application status of chlorine dioxide, compared the action mode, advantages and disadvantages of various disinfectants. The mechanism of chlorine dioxide inactivating bacteria, fungi and viruses were reviewed. The lethal target of chlorine dioxide to bacteria and fungi is to destroy the structure of cell membrane, change the permeability of cell membrane, and make intracellular substances flow out, leading to their death. The lethal targets for viruses are the destruction of viral protein capsids and the degradation of RNA fragments. The purpose of this review is to provide more scientific guidance for the application of chlorine dioxide disinfectants.
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Bacterias , Compuestos de Cloro , Desinfectantes , Desinfección , Hongos , Óxidos , Virus , Compuestos de Cloro/farmacología , Óxidos/farmacología , Desinfectantes/farmacología , Desinfección/métodos , Bacterias/efectos de los fármacos , Virus/efectos de los fármacos , Hongos/efectos de los fármacos , Purificación del Agua/métodos , HumanosRESUMEN
Human norovirus (HuNoV), the leading cause of foodborne acute gastroenteritis, poses a serious threat to public health. Traditional disinfection methods lead to destructions of food properties and functions, and/or environmental contaminations. Green and efficient approaches are urgently needed to disinfect HuNoV. Plasma-activated water (PAW) containing amounts of reactive species is an emerging nonthermal and eco-friendly disinfectant towards the pathogenic microorganisms. However, the disinfection efficacy and mechanism of PAW on HuNoV has not yet been studied. Murine norovirus 1 (MNV-1) is one of the most commonly used HuNoV surrogates to evaluate the efficacy of disinfectants. In the current study, the inactivation efficacy of MNV-1 by PAW was investigated. The results demonstrated that PAW significantly inactivated MNV-1, reducing the viral titer from approximately 6 log10 TCID50/mL to non-detectable level. The decreased pH, increased oxidation-reduction potential (ORP) and conductivity of PAW were observed compared with that of deionized water. Compositional analysis revealed that hydrogen peroxide (H2O2), nitrate (NO3-) and hydroxyl radical (OH) were the functional reactive species in MNV-1 inactivation. L-histidine could scavenge most of the inactivation effect in a concentration-dependent manner. Moreover, PAW could induce damage to viral proteins. Part of MNV-1 particles was destroyed, while others were structurally intact without infectiousness. After 45 days of storage at 4 °C, PAW generated with 80 % O2 and 100 % O2 could still reduce over 4 log10 TCID50/mL of the viral titer. In addition, PAW prepared using hard water induced approximately 6 log10 TCID50/mL reduction of MNV-1. PAW treatment of MNV-1-inoculated blueberries reduced the viral titer from 3.79 log10 TCID50/mL to non-detectable level. Together, findings of the current study uncovered the crucial reactive species in PAW inactivate MNV-1 and provided a potential disinfection strategy to combat HuNoV in foods, water, and environment.
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Desinfectantes , Desinfección , Peróxido de Hidrógeno , Norovirus , Inactivación de Virus , Agua , Norovirus/efectos de los fármacos , Norovirus/fisiología , Inactivación de Virus/efectos de los fármacos , Animales , Ratones , Agua/química , Desinfectantes/farmacología , Desinfección/métodos , Gases em Plasma/farmacología , Radical Hidroxilo/metabolismo , Nitratos/farmacología , Concentración de Iones de HidrógenoRESUMEN
With the outbreak and continued spread of the COVID-19 pandemic, people's demand for daily disinfection products has increased rapidly, and its innovative design has received widespread attention. In this context, this study aims to propose a design methodology for home entrance disinfection devices based on AHP-FAST-FBS. Firstly, the design requirements of the home entrance disinfection device were collected and analyzed through in-depth interviews and the KJ method, and a hierarchical model of design demand indicators was constructed. Secondly, the Analytical Hierarchy Process (AHP) was employed to quantify these design demand indicators, and core design demands for home entrance disinfection devices were identified by weight calculations. On this basis, the Functional Analysis System Technique (FAST) method was combined to rationally transform the design demands into product functional indicators, constructing a functional system model for the home entrance disinfection device through systematic decomposition and categorization. Lastly, based on the Function-Behavior-Structure (FBS) theoretical model, the mapping of each function of the product to its structure was realized, the product structure modules were determined, and the comprehensive design and output of the innovative design scheme for the home entrance disinfection device were completed. The results of this study indicate that the design methodology combining AHP-FAST-FBS can effectively improve the scientific rigor and effectiveness of the home entrance disinfection device design, thereby generating an ideal product design scheme. This study provides systematic theoretical guidance and practical reference for designers of subsequent related disinfection products and also offers a new path for improving social health and safety.
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COVID-19 , Desinfección , COVID-19/prevención & control , COVID-19/epidemiología , Humanos , Desinfección/métodos , Pandemias/prevención & control , SARS-CoV-2/aislamiento & purificación , Modelos TeóricosRESUMEN
BACKGROUND: Coronaviruses, a group of highly transmissible and potentially pathogenic viruses, can be transmitted indirectly to humans via fomites. To date, no study has investigated their persistence on carpet fibers. Establishing persistence is essential before testing the efficacy of a disinfectant. METHODS: The persistence of BCoV and HCoV OC43 on polyethylene terephthalate (PET) and nylon carpet was first determined using infectivity and RT-qPCR assays. Then, the disinfectant efficacy of steam vapor was evaluated against both coronaviruses on nylon carpet. RESULTS: Immediately after inoculation of carpet coupons, 32.50% of BCoV and 3.87% of HCoV OC43 were recovered from PET carpet, compared to 34.86% of BCoV and 24.37% of HCoV OC43 recovered from nylon carpet. After incubation at room temperature for 1 h, BCoV and HCoV OC43 showed a 3.6 and > 2.8 log10 TCID50 reduction on PET carpet, and a 0.6 and 1.8 log10 TCID50 reduction on nylon carpet. Based on first-order decay kinetics, the whole gRNA of BCoV and HCoV OC43 were stable with k values of 1.19 and 0.67 h- 1 on PET carpet and 0.86 and 0.27 h- 1 on nylon carpet, respectively. A 15-s steam vapor treatment achieved a > 3.0 log10 TCID50 reduction of BCoV and > 3.2 log10 TCID50 reduction of HCoV OC43 on nylon carpet. CONCLUSION: BCoV was more resistant to desiccation on both carpet types than HCoV OC43. Both viruses lost infectivity quicker on PET carpet than on nylon carpet. Steam vapor inactivated both coronaviruses on nylon carpet within 15 s.
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Desinfección , Vapor , Desinfección/métodos , Desinfectantes/farmacología , Pisos y Cubiertas de Piso , Tereftalatos Polietilenos , Nylons/farmacología , Humanos , Coronavirus/efectos de los fármacos , Animales , Coronavirus Humano OC43/efectos de los fármacos , Coronavirus Humano OC43/fisiologíaRESUMEN
Salmonella Typhimurium (S. Typhimurium) contamination poses a significant challenge to breeder egg hatchability and chick health, necessitating the exploration of alternative disinfection methods. This study investigates the potential of phage vB_SPuM_SP02 (SP02) as a novel disinfectant for breeder eggs contaminated with S. Typhimurium SM022. Phage SP02 was isolated from poultry farm effluent and characterized for morphology, biological properties, and genome properties. Experimental groups of specific pathogen-free (SPF) eggs were treated with Salmonella and phage SP02, and efficacy was assessed through hatching rates, chick survival, weight, Salmonella load, immune organ indices, and intestinal flora. Phage treatment effectively eradicated Salmonella contamination on eggshells within 12 h, resulting in increased hatching and survival rates compared to controls. Furthermore, phage treatment mitigated weight loss and tissue Salmonella load in chicks without causing immune organ damage while reducing Salmonella spp. abundance in the intestinal tract. This study demonstrates the potential of phage SP02 as an eco-friendly and efficient disinfectant for S. Typhimurium-contaminated breeder eggs, offering promising prospects for practical application in poultry production.
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Pollos , Huevos , Salmonelosis Animal , Fagos de Salmonella , Salmonella typhimurium , Animales , Salmonella typhimurium/virología , Fagos de Salmonella/fisiología , Fagos de Salmonella/aislamiento & purificación , Salmonelosis Animal/microbiología , Huevos/microbiología , Huevos/virología , Enfermedades de las Aves de Corral/microbiología , Enfermedades de las Aves de Corral/prevención & control , Enfermedades de las Aves de Corral/virología , Desinfectantes/farmacología , Desinfección/métodos , Organismos Libres de Patógenos Específicos , Bacteriófagos/fisiología , Bacteriófagos/aislamiento & purificación , Cáscara de Huevo/microbiologíaRESUMEN
Recently, seven dihalohydroxybenzonitriles (diHHBNs) have been determined as concerning nitrogenous aromatic disinfection byproducts (DBPs) in drinking water. Herein, eight new monohalohydroxybenzonitriles (monoHHBNs), including 3-chloro-2-hydroxybenzonitrile, 5-chloro-2-hydroxybenzonitrile, 3-chloro-4-hydroxybenzonitrile, 3-bromo-2-hydroxybenzonitrile, 5-bromo-2-hydroxybenzonitrile, 3-bromo-4-hydroxybenzonitrile, 5-iodo-2-hydroxybenzonitrile, and 3-iodo-4-hydroxybenzonitrile, were detected and identified in drinking water for the first time. Thereafter, the relative concentration-cytotoxicity contribution of each HHBN was calculated based on the acquired occurrence level and cytotoxicity data in this study, the genome-scale cytotoxicity mechanism was explored, and a quantitative structure-activity relationship (QSAR) model was developed. Results indicated that new monoHHBNs were present in drinking water at concentrations of 0.04-1.83 ng/L and exhibited higher cytotoxicity than some other monohalogenated aromatic DBPs. Notably, monoHHBNs showed concentration-cytotoxicity contribution comparable to diHHBNs, which have been previously identified as potential toxicity drivers in drinking water. Transcriptomic analysis revealed immunotoxicity and genotoxicity as dominant cytotoxicity mechanisms for HHBNs in Chinese hamster ovary (CHO-K1) cells, with potential carcinogenic effects. The QSAR model suggested oxidative stress and cellular uptake efficiency as important factors for their cytotoxicity, highlighting the importance of potential iodinated HHBNs in drinking water, such as 3,5-diiodo-2-hydroxybenzonitrile, for future studies. These findings are meaningful for better understanding the health risk and toxicological significance of HHBNs in drinking water.
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Desinfección , Agua Potable , Agua Potable/química , Animales , Contaminantes Químicos del Agua/toxicidad , Cricetulus , Células CHO , Desinfectantes/toxicidad , Nitrilos/toxicidad , Relación Estructura-Actividad Cuantitativa , Purificación del AguaRESUMEN
Research has demonstrated the difficulty associated with degrading the conventional 1-2 carbon aliphatic halogenated byproducts of disinfectant reactions with organic matter [disinfection byproducts (DBPs)] within advanced oxidation process (AOP) units in potable reuse trains, but the efficacy of AOP units for treating the emerging classes of halogenated aromatic DBPs is unclear. We herein demonstrate more effective removal of 28 halogenated aromatic DBPs in the UV/H2O2 AOP at 222 nm (UV222) than in the conventional UV/H2O2 AOP at 254 nm. Direct photolysis of 28 halogenated aromatic DBPs was greatly enhanced at 222 nm with fluence-based photodecay rate constants of 4.31 × 10-4-1.53 × 10-2 cm2 mJ-1, which was mainly attributed to the higher molar absorption coefficients of halogenated aromatic DBPs at 222 nm than 254 nm. Generally, quantum yields of halogenated aromatic DBPs at both 222 and 254 nm followed the order of halophenols > halohydroxybenzaldehydes > halonitrophenols. All 28 halogenated aromatic DBPs exhibit high reactivity toward HO⢠with second-order rate constants ranging from 2.18 × 109 to 1.15 × 1010 M-1 s-1 determined by X-ray radiolysis. The UV fluence required to achieve 90% loss of halogenated aromatic DBPs in the UV222/H2O2 AOP was 75-95% lower than that in the UV254/H2O2 AOP, and 90% removal of most tested halogenated aromatic DBPs can be achieved in the UV222/H2O2 AOP within the UV fluence levels commonly applied in potable reuse (700-1000 mJ cm-2).
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Desinfección , Peróxido de Hidrógeno , Oxidación-Reducción , Purificación del Agua , Peróxido de Hidrógeno/química , Purificación del Agua/métodos , Contaminantes Químicos del Agua/química , Rayos Ultravioleta , Agua Potable/química , Desinfectantes/química , FotólisisRESUMEN
The prevalence of airborne pathogens in indoor environments presents significant health risks due to prolonged human occupancy. This review addresses diverse air purification systems to combat airborne pathogens and the factors influencing their efficacy. Indoor aerosols, including bioaerosols, harbor biological contaminants from respiratory emissions, highlighting the need for efficient air disinfection strategies. The COVID-19 pandemic has emphasized the dangers of airborne transmission, highlighting the importance of comprehending how pathogens spread indoors. Various pathogens, from viruses like SARS-CoV-2 to bacteria like Mycobacterium (My) tuberculosis, exploit unique respiratory microenvironments for transmission, necessitating targeted air purification solutions. Air disinfection methods encompass strategies to reduce aerosol concentration and inactivate viable bioaerosols. Techniques like ultraviolet germicidal irradiation (UVGI), photocatalytic oxidation (PCO), filters, and unipolar ion emission are explored for their specific roles in mitigating airborne pathogens. This review examines air purification systems, detailing their operational principles, advantages, and limitations. Moreover, it elucidates key factors influencing system performance. In conclusion, this review aims to provide practical knowledge to professionals involved in indoor air quality management, enabling informed decisions for deploying efficient air purification strategies to safeguard public health in indoor environments.
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Microbiología del Aire , Contaminación del Aire Interior , COVID-19 , Desinfección , SARS-CoV-2 , Contaminación del Aire Interior/prevención & control , Desinfección/métodos , COVID-19/prevención & control , COVID-19/transmisión , HumanosRESUMEN
Sprouts are an attractive food product that contains high amounts of nutritional substances and has pro-health features. Sprout consumption has strongly increased despite its potential risk to health due to its microbial load. Both the safety and shelf life of sprouts may be negatively affected by a high microbial load. To reduce the microbial contamination in sprouts before consumption, the initial microbial load on the seeds needs to be controlled. Many herbal sprouts have been recommended for diabetes, and fenugreek is one of these sprouts. Thus, the current experiment aimed at disinfecting fenugreek seeds using microwave (5, 10, and 20 s) and hot water (30, 45, and 60 s) treatments for different durations. The best-disinfected sprouts with the highest nutritional properties were used to evaluate their influence on streptozocin-induced diabetic rats in comparison with fenugreek seed feeding. Microwave treatments showed the highest sprout length, fresh weight, total free amino acids, antioxidants, reducing sugars, and total phenols. Additionally, microwave seed treatments showed the lowest bacteria and mold counts on sprouts produced relative to hot water treatments, and the best seed treatment was a microwave for 20 s, which gave the best values in this respect. Feeding diabetic rats with different fenugreek seeds or sprout rates (0, 5, 7.5, and 10% w/w) improved body weight, restricted the growth of glucose levels, lowered total cholesterol and triglycerides, and improved HDL compared with the positive control group, and fenugreek sprouts at higher rates showed the maximum improvements in blood glucose, total cholesterol, and triglycerides. Treating fenugreek seed with microwave radiation for 20 s to disinfect the seeds before sprouting is recommended for lowering the microbial load with optimum nutritional and antioxidant activity, and feeding diabetic rats with these sprouts at the rate of 7.5 and 10% had promising effects on hyperglycemia and associated disorders.
Asunto(s)
Diabetes Mellitus Experimental , Valor Nutritivo , Semillas , Trigonella , Animales , Trigonella/química , Semillas/química , Ratas , Masculino , Glucemia/metabolismo , Glucemia/efectos de los fármacos , Desinfección/métodos , Microondas , Antioxidantes/farmacología , Ratas Wistar , Extractos VegetalesRESUMEN
PURPOSE: To evaluate the in vitro antibacterial effect of Softsoap and Efferdent used as solutions to disinfect Lucitone 199 poly(methyl methacrylate) (PMMA) resin used for dentures. METHODS: S. mutans and plaque bacteria were grown for 24 hours, and suspended to a concentration of 1x106 cells/ml. Bacterial suspensions (0.2 mL) were added to the decontaminated PMMA discs placed in a 48-well culture plate and incubated for 3 days at 37°C. The discs were rinsed to remove the unbound bacterial cells and then incubated for 60 minutes with 5% and 1% dilutions (triplicates) of each of the detergent solutions (0.3 ml). Discs were rinsed and then MTT reagent (0.2 ml) was added and incubated for 2 hours, then overnight with a solubilizing agent. An aliquot from each well (0.1 ml) was transferred to a 96-well flat bottom plate and absorbance was measured to OD @ 595 nm (MTT) of four samples for each data point. Normalized data was compared and statistically analyzed using a three-way ANOVA with Student-Newman-Keuls on Rank data with P< 0.05 for significance. Additionally, data were double-checked with the Holm-Sidak test. RESULTS: There was no statistically significant difference between testing media for C. albicans and mixed plaque (P= 0.078) or testing duration in time at 24 hours and 21 days (P= 0.07). Statistically significant differences were found between all treatment solutions group combinations (P< 0.001) except for 30% Softsoap versus Efferdent (P= 0.056). CLINICAL SIGNIFICANCE: There was no statistically significant difference between testing media for C. albicans and mixed plaque (P= 0.078) or testing duration at 24 hours and 21 days (P= 0.07). Statistically significant differences were noted between all treatment solutions group combinations (P< 0.001), However, there was no difference between 30% Softsoap and Efferdent (P= 0.056).