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1.
Viruses ; 13(3)2021 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-33807081

RESUMEN

The emergent human coronavirus SARS-CoV-2 and its high infectivity rate has highlighted the strong need for new disinfection systems. Evidence has proven that airborne transmission is an important route of spreading for this virus. Therefore, this short communication introduces CLODOS Technology®, a novel strategy to disinfect contaminated surfaces. It is a product based on stable and 99% pure chlorine dioxide, already certified as a bactericide, fungicide and virucide against different pathogens. In this study, CLODOS Technology®, by direct contact or thermonebulization, showed virucidal activity against the human coronavirus HCoV-229E at non-cytotoxic doses. Different conditions such as nebulization, exposure time and product concentration have been tested to standardize and optimize this new feasible method for disinfection.


Asunto(s)
Coronavirus Humano 229E/efectos de los fármacos , Desinfectantes/farmacología , Desinfección/métodos , Línea Celular , Compuestos de Cloro/análisis , Compuestos de Cloro/farmacología , Infecciones por Coronavirus/prevención & control , Infecciones por Coronavirus/virología , Desinfectantes/análisis , Desinfección/instrumentación , Humanos , Nebulizadores y Vaporizadores , Óxidos/análisis , Óxidos/farmacología
4.
Huan Jing Ke Xue ; 42(4): 1939-1945, 2021 Apr 08.
Artículo en Chino | MEDLINE | ID: mdl-33742829

RESUMEN

In order to study the effects of chlorine dioxide (ClO2) disinfection on the super antibiotic resistance genes (SARGs), the final effluents before and after chlorine dioxide were sampled throughout one year in a wastewater treatment plant (WWTP). The bacteria and extracellular nucleic acid were collected using microporous membrane filtration and nucleic acid adsorption particles, respectively. A total of 9 SARGs was detected through a quantitative real-time polymerase chain reaction (qPCR). The results revealed that both intracellular and extracellular NDM-1, MCR-1, and MEC-A could be positively detected in the samples. Overall, ClO2 disinfection enhanced the relative abundance of the iSARGs (P<0.05), exhibiting a seasonal pattern, and increasing in the spring, summer, and autumn. In spring, it improved the most, up to twice the abundance. No SARGs were detected positive in the winter, either intracellularly or extracellularly. There was no significant variation in the concentrations of eSARGs before and after ClO2 disinfection. Therefore, ClO2 disinfection cannot effectively remove iSARGs and eSARGs in the final effluent from the WWTP.


Asunto(s)
Compuestos de Cloro , Desinfectantes , Purificación del Agua , Antibacterianos/farmacología , Cloro , Compuestos de Cloro/farmacología , Desinfectantes/farmacología , Desinfección , Farmacorresistencia Microbiana/genética , Óxidos/farmacología
5.
Int J Food Microbiol ; 342: 109073, 2021 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-33550154

RESUMEN

Clam jeotgal, called "jogaejeotgal," is a Korean fermented seafood product with, generally, a high amount of added salt to inhibit the growth of pathogenic microorganisms. This study aimed to evaluate the efficacy of chlorine dioxide (ClO2) and sodium hypochlorite (NaOCl) against murine norovirus 1 (MNV-1), a surrogate for human norovirus, in salt-fermented clam, jogaejeotgal. The sequential effect of ClO2 and electron-beam (e-beam) irradiation on the inactivation of MNV-1 was also investigated. Treatments of up to 300 ppm ClO2 and 1000 ppm NaOCl were used to determine the disinfectant concentrations at which more than 1 log (90%) MNV-1 inactivation occurred. The sequential treatment of ClO2 (50-300 ppm) and e-beam (1-5.5 kGy) was performed after storage at 4 °C for 7 days. There was a 1.9-log reduction of the virus in seasoned clams irradiated at 5.5 kGy after ClO2 treatment at 300 ppm. No significant change (p > 0.05) in physicochemical quality was observed after the combined treatment, suggesting the potential for the use of a combined treatment using ClO2 (300 ppm) and e-beam (5.5 kGy) in the jeotgal manufacturing industry for the reduction of norovirus.


Asunto(s)
Bivalvos , Compuestos de Cloro/farmacología , Electrones , Norovirus/fisiología , Óxidos/farmacología , Mariscos/virología , Animales , Desinfectantes/farmacología , Irradiación de Alimentos , Conservación de Alimentos/métodos , Norovirus/efectos de los fármacos , Norovirus/efectos de la radiación , República de Corea , Mariscos/análisis , Hipoclorito de Sodio/farmacología , Inactivación de Virus/efectos de los fármacos , Inactivación de Virus/efectos de la radiación
6.
Environ Res ; 195: 110840, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33587946

RESUMEN

Intimate coupling of visible-light photocatalysis and biodegradation (ICPB) offers potential for degrading chlorine dioxide bleaching wastewater. In this study, we reported a TiO2-coated sponge biofilm carrier with significant adhesion of TiO2 and the ability to accumulate biomass in its interior. Four mechanisms possibly acting in ICPB were tested separately: adsorption of chlorine dioxide bleaching wastewater to the carrier, photolysis, photocatalysis, and biodegradation by the biofilm inside the carrier. The carrier had an adsorption capacity of 17% and 16% for CODcr and AOX, respectively, in the wastewater. The photodegradation rate of wastewater was very low and could be ignored. Both biodegradation (AOX 30.1%, CODcr 33.8%, DOC 26.2%) and photocatalysis (AOX 65.1%, CODcr 71.2%, DOC 62.3%) possessed a certain degradation efficiency of wastewater. However, the removal rate of AOX, CODcr, and DOC in wastewater treatment by protocol ICPB reached 80.3%, 90.5%, and 86.7%. FT-IR and GC-MS analysis showed that the ICPB system had photocatalytic activity on the surface of the porous carrier in vitro, which could transform organic into small molecules for microbial utilization or complete mineralization. Moreover, the biofilm in the interior of the TiO2-coated sponge carrier could mineralize the photocatalytic products, which enhanced the removal of AOX, CODcr, and DOC by more than 15.2%, 20.0%, and 24.0%, respectively. The biofilm in the carrier of the ICPB system evolved, enriched in Proteobacteria, Chloroflexi, Bacteroidetes, and Actinobacteria, microorganisms known to play active roles in the biodegradation of papermaking wastewater.


Asunto(s)
Titanio , Aguas Residuales , Biodegradación Ambiental , Catálisis , Compuestos de Cloro , Óxidos , Fotólisis , Espectroscopía Infrarroja por Transformada de Fourier
7.
Bull Environ Contam Toxicol ; 106(4): 560-567, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33629148

RESUMEN

Chlorine dioxide (ClO2), an alternative disinfectant to chlorine, has been widely applied in water and wastewater disinfection. This paper aims at presenting an overview of the inactivation kinetics and mechanisms of ClO2 with viruses. The inactivation efficiencies vary greatly among different virus species. The inactivation rates for different serotypes within a family of viruses can differ by over 284%. Generally, to achieve a 4-log removal, the exposure doses, also being referred to as Ct values (mutiplying the concentration of ClO2 and contact time) vary in the range of 0.06-10 mg L-1 min. Inactivation kinetics of viruses show two phases: an initial rapid inactivation phase followed by a tailing phase. Inactivation rates of viruses increase as pH or temperature increases, but show different trends with increasing concentrations of dissolved organic matter (DOM). Both damages in viral proteins and in the 5' noncoding region within the genome contribute to virus inactivation upon ClO2 disinfection.


Asunto(s)
Compuestos de Cloro , Desinfectantes , Purificación del Agua , Cloro , Compuestos de Cloro/toxicidad , Desinfectantes/toxicidad , Cinética , Óxidos/toxicidad , Inactivación de Virus , Agua
8.
Ecotoxicol Environ Saf ; 211: 111907, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33453637

RESUMEN

Oxidation of phenol, cyanide and aniline have been analyzed by the enhanced electro-oxidation process in which sodium chlorite was used as an electrolyte and results were validated using statistical tool based on Box-Behnken design. The mineralization efficiency of 78.4%, and 98.18% were predicted at optimized variables condition for phenol, and aniline respectively, whereas complete mineralization has been observed for the cyanide at the optimized conditions, which describes the significance of the design model approach.The process mineralizes the higher phenol concentration revealing a drastic reduction in power consumption in comparison of direct oxidation, i.e., 799.36 kWh/kg to 138.18 kWh/kg for more than 90% mineralization of phenol even at a higher current density of 13.63 mA/cm2. The kinetic modelling approach justified that higher current density has also played a role in higher mineralization of pollutants at the specific operating conditions. The by-product formation and toxicity effect on microalgae in wastewater were assessed by the full scan mass spectrometry and microalgae pigment inhibition test after the electro-oxidation of coking wastewater. The pigment growth inhibition rate of Chlorella sp. NCQ and Micractinium sp. NCS2 suggests that sodium chlorite as an electrolyte aid can also effectively used as an oxidizing agent and algal inhibiter in the coking wastewater.


Asunto(s)
Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/toxicidad , Compuestos de Anilina , Chlorella , Compuestos de Cloro , Coque/análisis , Cianuros/análisis , Contaminantes Ambientales/análisis , Peróxido de Hidrógeno/química , Microalgas , Oxidación-Reducción , Óxidos , Fenol/análisis , Aguas Residuales/química , Contaminantes Químicos del Agua/análisis
9.
Int J Food Microbiol ; 337: 108938, 2021 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-33166912

RESUMEN

A packaging system using gaseous chlorine dioxide generating film (CDGF) in a sealed container was developed to extend the shelf life of semi-dry longan pulp (moisture content 38.8 wt%; aw0.8). The antimicrobial properties, formation of chloroxyanion residues and effects of CDGF on the quality of semi-dry longan pulp were investigated. CDGF was triggered by the moisture vapor from semi-dry longan pulp in the sealed container and released gaseous ClO2 into the headspace of the container. The antifungal test showed that CDGF significantly inactivated artificially inoculated molds in semi-dry longan pulp and achieved reductions of over 3 log CFU/g after 28 days storage at room temperature (25 °C). CDGF reduced total aerobic bacterial populations by over 6.4 log CFU/g and maintained these population levels at around 2.0 log CFU/g throughout the 180-day storage period at room temperature. The residual concentrations of chloride, chlorate and perchlorate in longan pulp increased and then decreased during the 180-day storage. Residual chloride levels were maintained at 1.5 mg/g after Day 120 and residual chlorate and perchlorate levels were not detected after Day 120 and Day 180, respectively, in CDGF-treated samples. CDGF treatments reduced total polyphenol content but didn't have any significant impact on the levels of polysaccharides in samples. There were no significant differences between CDGF-treated and control samples in color changes during storage. The content of 5-hydroymethylfurfural (5-HMF) in both samples increased during storage, suggesting that the Maillard reaction occurred. This study demonstrated an effective approach to develop a new antimicrobial packaging system for semi-dry longan pulp.


Asunto(s)
Compuestos de Cloro/farmacología , Microbiología de Alimentos , Almacenamiento de Alimentos/métodos , Óxidos/farmacología , Cloruros/análisis , Recuento de Colonia Microbiana , Desinfectantes/farmacología , Hongos/efectos de los fármacos , Gases/farmacología , Percloratos/análisis , Sapindaceae/microbiología
10.
Chemosphere ; 262: 127904, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32799153

RESUMEN

Manganese accumulated in corrosion scales on drinking water distribution systems (DWDSs) can be released into bulk water, causing discolouration and thereby leading to customer concerns about drinking water quality. A static release experiment was conducted on iron pipe scales under three different temperatures, pH values, alkalinity values, sulfate (SO42-) concentrations, and disinfectants to study the separate effect of these factors on Mn release from pipe scales under stagnant conditions. Results showed that more Mn was released from corrosion scales under the conditions of lower pH, lower alkalinity, higher temperature, and higher SO42- concentrations. Three commonly used disinfectants, sodium hypochlorite (NaClO), chlorine dioxide (ClO2), and monochloramine (NH2Cl) were found to inhibit the release of Mn from iron corrosion scales, with the ranked order of inhibitory effect of ClO2≈NaClO > NH2Cl under the same CT (product of disinfectant concentration and contact time) value. The orthogonal experimental results indicated that SO42- and alkalinity had extremely significant effects on the release of Mn from pipe scales, while pH and disinfectant type had a significant impact on the release of Mn from pipe scales. Thus, the SO42- concentration and alkalinity of the bulk water should be determined to avoid excessive release of Mn into drinking water. However, further investigation of the effect of disinfectants on Mn release in DWDSs is necessary. This research helps establish a systematic understanding of the influential factors in Mn release from pipe scales into bulk water, as well as their significant relationships.


Asunto(s)
Agua Potable/química , Manganeso/análisis , Contaminantes Químicos del Agua/análisis , Compuestos de Cloro , Corrosión , Desinfectantes/análisis , Concentración de Iones de Hidrógeno , Hierro , Óxidos , Sulfatos/análisis , Temperatura , Calidad del Agua , Abastecimiento de Agua
11.
Water Res ; 188: 116520, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33091806

RESUMEN

Chlorine dioxide (ClO2) is a prevalently used disinfectant alternative to chlorine, due to its effectiveness in pathogen inactivation and low yields of organic halogenated disinfection byproducts (DBPs). However, during ClO2 generation, chlorine is inevitably introduced into the obtained ClO2 solution as an "impurity", which could compromise the merits of ClO2 disinfection. In this study, drinking water disinfection with ClO2 containing 0‒25% chlorine impurity (i.e., at Cl2 to ClO2 mass ratios of 0‒25%) was simulated, and the effect of chlorine impurity on the DBP formation and developmental toxicity of the finished water was evaluated. With increasing the chlorine impurity in ClO2, the chlorite level kept decreasing and the chlorate level gradually increased; meanwhile, an unexpected trend from decline to rise was observed for the total organic halogenated DBPs, with the minimum level appearing at 5% chlorine impurity. To unravel the mechanisms for the variations of organic halogenated DBPs with chlorine impurity, a quantitative kinetic model was developed to simulate the formation of chlorinated, brominated, and iodinated DBPs in the ClO2-disinfected drinking water. The modeling results indicated that reactions involving iodide accounted for the decrease of organic halogenated DBPs at a relatively low chlorine impurity level. In accordance with DBP formation, ClO2 with 5% chlorine impurity generated less toxic drinking water than pure ClO2, while significantly higher developmental toxicity was induced until the chlorine impurity reached 25%. For E. coli inactivation, the presence of chlorine impurity enhanced the disinfection efficiency due to a synergistic effect of ClO2 and chlorine. Therefore, disinfection practices with ClO2 containing low chlorine impurity (e.g., <10%) might be favored (i.e., there is no need to eliminate low chlorine impurity in the ClO2 solution), while those containing high chlorine impurity should be concerned.


Asunto(s)
Desinfectantes , Contaminantes Químicos del Agua , Purificación del Agua , Cloro , Compuestos de Cloro , Desinfección , Escherichia coli , Halogenación , Óxidos , Contaminantes Químicos del Agua/análisis
12.
PLoS Negl Trop Dis ; 14(9): e0008539, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32956374

RESUMEN

During the initial phase of the 2014-2016 Ebola virus disease (EVD) outbreak in Monrovia, Liberia, all hospitals' isolation capacities were overwhelmed by the sheer caseload. As a stop-gap measure to halt transmission, Medecins sans Frontieres (MSF) distributed household disinfection kits to those who were at high risk of EVD contamination. The kit contained chlorine and personal protective materials to be used for the care of a sick person or the handling of a dead body. This intervention was novel and controversial for MSF. This paper shed the light on this experience of distribution in Monrovia and assess if kits were properly used by recipients. Targeted distribution was conducted to those at high risk of EVD (relatives of confirmed EVD cases) and health staff. Mass distributions were also conducted to households in the most EVD affected urban districts. A health promotion strategy focused on the purpose and use of the kit was integrated into the distribution. Follow-up phone calls to recipients were conducted to enquire about the use of the kit. Overall, 65,609 kits were distributed between September and November 2014. A total of 1,386 recipients were reached by phone. A total of 60 cases of sickness and/or death occurred in households who received a kit. The majority of these (46, 10%) were in households of relatives of confirmed EVD cases. Overall, usage of the kits was documented in 56 out of 60 affected households. Out of the 1322 households that did not experience sickness and/or death after the distribution, 583 (44%) made use of elements of the kit, mainly (94%) chlorine for hand-washing. At the peak of an EVD outbreak, the distribution of household disinfection kits was feasible and kits were appropriately used by the majority of recipients. In similar circumstances in the future, the intervention should be considered.


Asunto(s)
Desinfectantes , Promoción de la Salud/métodos , Fiebre Hemorrágica Ebola/prevención & control , Equipo de Protección Personal , Compuestos de Cloro , Brotes de Enfermedades/prevención & control , Ebolavirus , Humanos , Control de Infecciones/instrumentación , Control de Infecciones/métodos , Liberia
13.
Food Chem ; 333: 127500, 2020 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-32693317

RESUMEN

The objectives of this study were to optimize the condition of ultrasonic treatment combined with aqueous chlorine dioxide (ClO2) on nitrate content of spinach by response surface methodology (RSM), and determine the effectiveness of ultrasound (US) and ClO2 alone and in combination, on spinach postharvest quality during 7 days' storage period. The optimal treatment parameters obtained were ultrasonic power (300 W), ClO2 concentration (50 ppm), treatment time (4 min). The combined treatments significantly reduced the nitrate content and maintained better storage quality in terms of total soluble solids (TSS) and ascorbic acid content compared with the individual treatment or untreated. For Chlorophyll content, the combined treatment was significantly higher than the control and ClO2 treatment, but lower than ultrasonic treatment. The results demonstrated that US combined with ClO2 are promising alternatives for the reduction of nitrate content, as well as preserving the quality of stored leafy vegetables.


Asunto(s)
Compuestos de Cloro/farmacología , Conservación de Alimentos/métodos , Conservantes de Alimentos/farmacología , Nitratos/análisis , Óxidos/farmacología , Spinacia oleracea/química , Ultrasonido/métodos , Ácido Ascórbico/análisis , Clorofila/análisis , Conservación de Alimentos/instrumentación , Almacenamiento de Alimentos , Hojas de la Planta/química , Spinacia oleracea/efectos de los fármacos , Verduras/química , Verduras/efectos de los fármacos
15.
Environ Monit Assess ; 192(7): 422, 2020 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-32519186

RESUMEN

Chlorine dioxide has been reported as very efficiently removing pesticides and other organic compounds from water matrixes. Due to pesticide toxicity and potential toxicity of their degradation products, it is important to monitor these compounds as environmental pollutants in ground and surface waters. Evaluating the effects of chlorine dioxide treatment is necessary, and toxicity studies are used to ascertain the severity of effects of intermediates due to incomplete degradation of the parent compounds. In this paper, for the first time, chlorine dioxide is applied and evaluated for the removal of chloroacetamide herbicides (pethoxamid and metazachlor) from waters (deionized water and Sava River water). The degradation degree of herbicides was measured by high-performance liquid chromatography, the main degradation products were identified using gas chromatography with a triple quadrupole mass detector, and the degree of mineralization was monitored by total organic carbon analysis. Four and two degradation products were identified after pethoxamid and metazachlor degradation, respectively. Total organic carbon analysis showed mineralization occurred, but it was incomplete. The mineralization and the characteristics of the degradation products obtained were tested using Daphnia magna and showed lower toxicity than the parent herbicides. The advantage of the applied treatment was a very high degradation percentage for pethoxamid removal from deionized water and Sava River water (100% and 97%, respectively), with higher mineralization efficiency (65%) than metazachlor. Slightly lower degradation efficiency in the Sava River water was due to chlorine dioxide oxidizing the herbicides and dissolved organic matter simultaneously.


Asunto(s)
Acetamidas , Compuestos de Cloro , Óxidos , Contaminantes Químicos del Agua , Purificación del Agua , Acetamidas/análisis , Acetamidas/química , Acetamidas/metabolismo , Acetamidas/toxicidad , Animales , Compuestos de Cloro/química , Daphnia/efectos de los fármacos , Ecotoxicología , Óxidos/química , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/metabolismo , Contaminantes Químicos del Agua/toxicidad , Purificación del Agua/métodos
16.
Food Chem ; 328: 127121, 2020 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-32474241

RESUMEN

Chlorine dioxide (ClO2) gas was utilized for detoxifying aflatoxin B1 (AFB1) in corn for the first time. Four degradation compounds were identified by LC-MS as C17H13O8, C17H15O10, C16H15O10, and C15H11O8. Structurally, the biological activity of ClO2-treated AFB1 was removed due to the disappearance of C8-C9 double bond in the furan ring and the modification of cyclopentanone and methoxy after ClO2 treatment. The cell viability assay on human embryo hepatocytes confirmed little toxicity of the degradation products. The degradation efficiency of AFB1 on corn peaked near 90.0% under the optimized conditions and reached 79.6% for low initial contamination of AFB1 at 5-20 µg/kg. Accordingly, ClO2 has the potential to be developed into an effective, efficient, and economic approach to detoxify AFB1 in grains.


Asunto(s)
Aflatoxina B1/química , Compuestos de Cloro/química , Cloro/química , Óxidos/química , Zea mays/química , Cromatografía Líquida de Alta Presión , Espectrometría de Masas
17.
J Environ Sci (China) ; 93: 129-136, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32446448

RESUMEN

Chlorine dioxide (ClO2), an alternative disinfectant to chlorine, has a superior ability to inactivate microorganisms, in which protein damage has been considered as the main inactivation mechanism. However, the reactivity of ClO2 with amino acid residues in oligopeptides and proteins remains poorly investigated. In this research, we studied the reaction rate constants of ClO2 with tryptophan residues in five heptapeptides and four proteins using stopped-flow or competition kinetic method. Each heptapeptide and protein contain only one tryptophan residue and the reactivity of tryptophan residue with ClO2 was lower than that of free tryptophan (3.88 × 104 (mol/L)-1sec-1 at pH 7.0). The neighboring amino acid residues affected the reaction rates through promoting inter-peptide aggregation, changing electron density, shifting pKa values or inducing electron transfer via redox reactions. A single amino acid residue difference in oligopeptides can make the reaction rate constants differ by over 60% (e.g. 3.01 × 104 (mol/L)-1sec-1 for DDDWNDD and 1.85 × 104 (mol/L)-1sec-1 for DDDWDDD at pH 7.0 (D: aspartic acid, W: tryptophan, N: asparagine)). The reaction rates of tryptophan-containing oligopeptides were also highly pH-dependent with higher reactivity for deprotonated tryptophan than the neutral specie. Tryptophan residues in proteins spanned a 4-fold range reactivity toward ClO2 (i.e. 0.84 × 104 (mol/L)-1sec-1 for ribonuclease T1 and 3.21 × 104 (mol/L)-1sec-1 for melittin at pH 7.0) with accessibility to the oxidant as the determinating factor. The local environment surrounding the tryptophan residue in proteins can also accelerate the reaction rates by increasing the electron density of the indole ring of tryptophan or inhibit the reaction rates by inducing electron transfer reactions. The results are of significance in advancing understanding of ClO2 oxidative reactions with proteins and microbial inactivation mechanisms.


Asunto(s)
Compuestos de Cloro , Triptófano , Cloro , Oligopéptidos , Óxidos
18.
Environ Sci Pollut Res Int ; 27(21): 27147-27160, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32399889

RESUMEN

Chlorine dioxide (ClO2) degradation of the organophosphorus pesticides azamethiphos (AZA) and dimethoate (DM) (10 mg/L) in deionized water and in Sava River water was investigated for the first time. Pesticide degradation was studied in terms of ClO2 level (5 and 10 mg/L), degradation duration (0.5, 1, 2, 3, 6, and 24 h), pH (3.00, 7.00, and 9.00), and under light/dark conditions in deionized water. Degradation was monitored using high-performance liquid chromatography. Gas chromatography coupled with triple quadrupole mass detector was used to identify degradation products of pesticides. Total organic carbon was measured to determine the extent of mineralization after pesticide degradation. Real river water was used under recommended conditions to study the influence of organic matter on pesticide degradation. High degradation efficiency (88-100% for AZA and 85-98% for DM) was achieved in deionized water under various conditions, proving the flexibility of ClO2 degradation for the examined organophosphorus pesticides. In Sava River water, however, extended treatment duration achieved lower degradation efficiency, so ClO2 oxidized both the pesticides and dissolved organic matter in parallel. After degradation, AZA produced four identified products (6-chlorooxazolo[4,5-b]pyridin-2(3H)-one; O,O,S-trimethyl phosphorothioate; 6-chloro-3-(hydroxymethyl)oxazolo[4,5-b]pyridin-2(3H)-one; O,O-dimethyl S-hydrogen phosphorothioate) and DM produced three (O,O-dimethyl S-(2-(methylamino)-2-oxoethyl) phosphorothioate; e.g., omethoate; S-(2-(methylamino)-2-oxoethyl) O,O-dihydrogen phosphorothioate; O,O,S-trimethyl phosphorodithioate). Simple pesticide degradation mechanisms were deduced. Daphnia magna toxicity tests showed degradation products were less toxic than parent compounds. These results contribute to our understanding of the multiple influences that organophosphorus pesticides and their degradation products have on environmental ecosystems and to improving pesticide removal processes from water.


Asunto(s)
Plaguicidas , Contaminantes Químicos del Agua , Purificación del Agua , Animales , Compuestos de Cloro , Dimetoato , Ecosistema , Organotiofosfatos , Óxidos
19.
J Food Sci ; 85(5): 1411-1417, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32249422

RESUMEN

Tiger frog (Rana tigrina) meat is extremely perishable. This study investigated the antimicrobial efficacy of chlorine dioxide (ClO2 ) on frog meat, optimized the formulation of a phosphate-based enhancement solution by response surface methodology (RSM), and determined the quality parameters (i.e., total aerobic counts [TAC], pH, drip loss, cooking loss, color measurements, shear force, total volatile basic nitrogen [TVB-N], and thiobarbituric acid-reactive substances [TBARS]) of refrigerated frog meat pretreated with ClO2 and the optimized blend of phosphates. Treatments of frog meat with 35 and 70 ppm ClO2 for 3, 5, and 10 min achieved a 0.7-, 0.9- and 0.9-, and 0.8-, 1.4- and 1.6-log CFU/g reduction of TAC, respectively, indicating the antimicrobial efficacy of ClO2 was concentration- and time-dependent with such that higher concentrations and/or longer exposure time achieved greater bacterial reductions. The concentrations of the phosphates, including sodium tripolyphosphate (STPP), sodium pyrophosphate (SPP), and sodium hexametaphosphate (SHMP), were optimized as the formula of 0.3% STPP and 0.45% SPP obtaining the highest water retention of the frog meat. After washed with 70 ppm ClO2 for 10 min and subsequently soaked with 0.3% STPP and 0.45% SPP for 30 min, the frog meat stored at 4 °C shown significantly (P < 0.05) lower TAC (<4.4 log CFU/g) and higher water holding capacity during the whole storage of 12 days, compared to the control. Results indicated that the two-step process may be applicable to slow down deterioration and maintain quality frog meat during refrigeration. PRACTICAL APPLICATION: This research provides a means to slow down deterioration, maintain quality frog meat, and improve stability during refrigeration. Refrigerated frog meat products, which are preferred by consumers with juicier and more tender texture compared to the frozen-thawed meat, could be developed by the frog industry based on the data from this study.


Asunto(s)
Compuestos de Cloro/análisis , Conservación de Alimentos/métodos , Conservantes de Alimentos/análisis , Carne/análisis , Óxidos/análisis , Fosfatos/análisis , Animales , Culinaria , Difosfatos/análisis , Conservación de Alimentos/instrumentación , Almacenamiento de Alimentos , Polifosfatos/análisis , Ranidae , Refrigeración , Sustancias Reactivas al Ácido Tiobarbitúrico/análisis , Agua/análisis
20.
Physiol Int ; 107(1): 1-11, 2020 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-32208977

RESUMEN

Motivation: Viruses have caused many epidemics throughout human history. The novel coronavirus [10] is just the latest example. A new viral outbreak can be unpredictable, and development of specific defense tools and countermeasures against the new virus remains time-consuming even in today's era of modern medical science and technology. In the lack of effective and specific medication or vaccination, it would be desirable to have a nonspecific protocol or substance to render the virus inactive, a substance/protocol, which could be applied whenever a new viral outbreak occurs. This is especially important in cases when the emerging new virus is as infectious as SARS-CoV-2 [4]. Aims and structure of the present communication: In this editorial, we propose to consider the possibility of developing and implementing antiviral protocols by applying high purity aqueous chlorine dioxide (ClO2) solutions. The aim of this proposal is to initiate research that could lead to the introduction of practical and effective antiviral protocols. To this end, we first discuss some important properties of the ClO2 molecule, which make it an advantageous antiviral agent, then some earlier results of ClO2 gas application against viruses will be reviewed. Finally, we hypothesize on methods to control the spread of viral infections using aqueous ClO2 solutions.


Asunto(s)
Betacoronavirus , Compuestos de Cloro/farmacología , Enfermedades Transmisibles Emergentes , Infecciones por Coronavirus , Transmisión de Enfermedad Infecciosa/prevención & control , Óxidos/farmacología , Pandemias , Neumonía Viral , Antivirales/farmacología , Betacoronavirus/efectos de los fármacos , Betacoronavirus/patogenicidad , Betacoronavirus/fisiología , Protocolos Clínicos , Enfermedades Transmisibles Emergentes/prevención & control , Enfermedades Transmisibles Emergentes/virología , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/prevención & control , Infecciones por Coronavirus/transmisión , Infecciones por Coronavirus/virología , Desinfectantes/farmacología , Humanos , Pandemias/prevención & control , Soluciones Farmacéuticas/farmacología , Neumonía Viral/epidemiología , Neumonía Viral/prevención & control , Neumonía Viral/transmisión , Neumonía Viral/virología , Proyectos de Investigación
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