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1.
Sci Rep ; 14(1): 12836, 2024 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-38834660

RESUMO

This study introduces an evaluation methodology tailored for bioreactors, with the aim of assessing the stress experienced by algae due to harmful contaminants released from antifouling (AF) paints. We present an online monitoring system equipped with an ultra-sensitive sensor that conducts non-invasive measurements of algal culture's optical density and physiological stage through chlorophyll fluorescence signals. By coupling the ultra-sensitive sensor with flash-induced chlorophyll fluorescence, we examined the dynamic fluorescence changes in the green microalga Chlamydomonas reinhardtii when exposed to biocides. Over a 24-h observation period, increasing concentrations of biocides led to a decrease in photosynthetic activity. Notably, a substantial reduction in the maximum quantum yield of primary photochemistry (FV/FM) was observed within the first hour of exposure. Subsequently, we detected a partial recovery in FV/FM; however, this recovery remained 50% lower than that of the controls. Integrating the advanced submersible sensor with fluorescence decay kinetics offered a comprehensive perspective on the dynamic alterations in algal cells under the exposure to biocides released from antifouling coatings. The analysis of fluorescence relaxation kinetics revealed a significant shortening of the fast and middle phases,  along with an increase in the duration of the slow phase, for the coating with the highest levels of biocides. Combining automated culturing and measuring methods, this approach has demonstrated its effectiveness as an ultrasensitive and non-invasive tool for monitoring the physiology of photosynthetic cultures. This is particularly valuable in the context of studying microalgae and their early responses to various environmental conditions, as well as the potential to develop an AF system with minimal harm to the environment.


Assuntos
Reatores Biológicos , Chlamydomonas reinhardtii , Chlamydomonas reinhardtii/efeitos dos fármacos , Chlamydomonas reinhardtii/metabolismo , Desinfetantes/farmacologia , Fluorescência , Fotossíntese/efeitos dos fármacos , Clorofila/metabolismo , Poluentes Químicos da Água/análise
2.
Sci Rep ; 14(1): 12651, 2024 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-38825618

RESUMO

Effective disinfection methods are crucial in the cold chain transportation process of food due to the specificity of temperature and the diversity of contaminated flora. The objective of this study was to investigate the sanitizing effect of different disinfectants on various fungi at - 20 °C to achieve accurate disinfection of diverse bacterial populations. Peracetic acid, hydrogen peroxide, and potassium bisulfate were selected as low-temperature disinfectants and were combined with antifreeze. The sanitizing effect of these cryogenic disinfectants on pathogens such as Bacillus subtilis black variant spores (ATCC9372), Staphylococcus aureus (ATCC 6538), Candida albicans (ATCC 10231), Escherichia coli (8099), and poliovirus (PV-1) was sequentially verified by bactericidal and virus inactivation experiments. After a specified time of disinfection, a neutralizing agent was used to halt the sanitizing process. The study demonstrates that different disinfectants exhibit selective effects during the low-temperature disinfection process. Peracetic acid, hydrogen peroxide, and potassium monopersulfate are suitable for the low-temperature environmental disinfection of bacterial propagules, viruses, and fungal contaminants. However, for microorganisms with strong resistance to spores, a low-temperature disinfectant based on peracetic acid should be chosen for effective disinfection treatment. Our results provide a valuable reference for selecting appropriate disinfectants to sanitize various potential pathogens in the future.


Assuntos
Temperatura Baixa , Desinfetantes , Desinfecção , Peróxido de Hidrogênio , Ácido Peracético , Desinfetantes/farmacologia , Desinfecção/métodos , Peróxido de Hidrogênio/farmacologia , Ácido Peracético/farmacologia , Sulfatos/farmacologia , Bacillus subtilis/efeitos dos fármacos , Compostos de Potássio/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Poliovirus/efeitos dos fármacos
3.
BMC Oral Health ; 24(1): 648, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824549

RESUMO

BACKGROUND: Ensuring the safety of dental unit waterlines (DUWLs) has become a pivotal issue in dental care practices, focusing on the health implications for both patients and healthcare providers. The inherent structure and usage conditions of DUWLs contribute to the risk of biofilm formation and bacterial growth, highlighting the need for effective disinfection solutions.The quest for a disinfection method that is both safe for clinical use and effective against pathogens such as Staphylococcus aureus and Escherichia coli in DUWLs underscores the urgency of this research. MATERIALS: Chlorine dioxide disinfectants at concentrations of 5, 20, and 80 mg/L were used to treat biofilms of S. aureus and E. coli cultured in DUWLs. The disinfection effectiveness was assessed through bacterial counts and culturing. Simultaneously, human skin fibroblast cells were treated with the disinfectant to observe changes in cell morphology and cytotoxicity. Additionally, the study included corrosion tests on various metals (carbon steel, brass, stainless steel, aluminum, etc.). RESULTS: Experimental results showed that chlorine dioxide disinfectants at concentrations of 20 mg/L and 80 mg/L significantly reduced the bacterial count of S. aureus and E. coli, indicating effective disinfection. In terms of cytotoxicity, higher concentrations were more harmful to cellular safety, but even at 80 mg/L, the cytotoxicity of chlorine dioxide remained within controllable limits. Corrosion tests revealed that chlorine dioxide disinfectants had a certain corrosive effect on carbon steel and brass, and the degree of corrosion increased with the concentration of the disinfectant. CONCLUSION: After thorough research, we recommend using chlorine dioxide disinfectant at a concentration of 20 mg/L for significantly reducing bacterial biofilms in dental unit waterlines (DUWLs). This concentration also ensures satisfactory cell safety and metal corrosion resistance.


Assuntos
Biofilmes , Compostos Clorados , Equipamentos Odontológicos , Desinfecção , Escherichia coli , Óxidos , Staphylococcus aureus , Compostos Clorados/farmacologia , Óxidos/farmacologia , Biofilmes/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Humanos , Staphylococcus aureus/efeitos dos fármacos , Desinfecção/métodos , Equipamentos Odontológicos/microbiologia , Desinfetantes/farmacologia , Desinfetantes de Equipamento Odontológico/farmacologia , Fibroblastos/efeitos dos fármacos , Carga Bacteriana/efeitos dos fármacos , Técnicas In Vitro
4.
PLoS One ; 19(5): e0302967, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38722908

RESUMO

Ricin is a highly toxic protein, capable of inhibiting protein synthesis within cells, and is produced from the beans of the Ricinus communis (castor bean) plant. Numerous recent incidents involving ricin have occurred, many in the form of mailed letters resulting in both building and mail sorting facility contamination. The goal of this study was to assess the decontamination efficacy of several commercial off-the-shelf (COTS) cleaners and decontaminants (solutions of sodium hypochlorite [bleach], quaternary ammonium, sodium percarbonate, peracetic acid, and hydrogen peroxide) against a crude preparation of ricin toxin. The ricin was inoculated onto four common building materials (pine wood, drywall joint tape, countertop laminate, and industrial carpet), and the decontaminants were applied to the test coupons using a handheld sprayer. Decontamination efficacy was quantified using an in-vitro cytotoxicity assay to measure the quantity of bioactive ricin toxin extracted from test coupons as compared to the corresponding positive controls (not sprayed with decontaminant). Results showed that decontamination efficacy varied by decontaminant and substrate material, and that efficacy generally improved as the number of spray applications or contact time increased. The solutions of 0.45% peracetic acid and the 20,000-parts per million (ppm) sodium hypochlorite provided the overall best decontamination efficacy. The 0.45% peracetic acid solution achieved 97.8 to 99.8% reduction with a 30-min contact time.


Assuntos
Descontaminação , Ricina , Descontaminação/métodos , Hipoclorito de Sódio/farmacologia , Hipoclorito de Sódio/química , Materiais de Construção , Ácido Peracético/farmacologia , Ácido Peracético/química , Peróxido de Hidrogênio/química , Animais , Desinfetantes/farmacologia , Desinfetantes/química
5.
Pak J Pharm Sci ; 37(2): 399-404, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38767107

RESUMO

Hair loss (alopecia) continues to be an issue for both sexes. There are multiple ways to reduce the effects of alopecia, one of which is topical minoxidil (MXD). This study aimed to test the effects of minoxidil nanoliposomes (MXD-NLs) on the hair of mice, compared with free MXD and to examine the disinfectant ability of MXD-NLs toward scalp bacteria. To test the study hypothesis, MXD-NLs and free MXD were prepared. Mouse hair was shaved prior to the experiment. MXD-NLs, free MXD and their vehicles were applied for 15 days. In addition, dermal swabs were used to isolate scalp bacteria and test the inhibitory effect of pretreated media with the two formulations and their vehicles. The results revealed that hair growth in the MXD-NLs -treated group (0.65±0.1cm) was higher than that in the free MXD -treated group (0.53±0.2cm). In addition, MXD-NLs treated media reduced the number of scalp bacteria (p=0.0456) compared with free MXD. These results reveal a novel formulation of MXD with faster hair growth properties and a better disinfectant effect than free MXD. This study can help future researchers to expand and develop MXD-NLs.


Assuntos
Alopecia , Cabelo , Lipossomos , Minoxidil , Couro Cabeludo , Minoxidil/farmacologia , Animais , Cabelo/crescimento & desenvolvimento , Cabelo/efeitos dos fármacos , Cabelo/microbiologia , Couro Cabeludo/efeitos dos fármacos , Camundongos , Alopecia/tratamento farmacológico , Alopecia/microbiologia , Nanopartículas , Desinfetantes/farmacologia , Masculino , Feminino
6.
Environ Microbiol Rep ; 16(3): e13274, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38775382

RESUMO

The pathogenic fungus Batrachochytrium dendrobatidis has caused declines of amphibians worldwide. Yet our understanding of how water quality influences fungal pathogenicity is limited. Here, we reviewed experimental studies on the effect of water quality on this pathogen to determine which parameters impacted disease dynamics consistently. The strongest evidence for protective effects is salinity which shows strong antifungal properties in hosts at natural levels. Although many fungicides had detrimental effects on the fungal pathogen in vitro, their impact on the host is variable and they can worsen infection outcomes. However, one fungicide, epoxiconazole, reduced disease effects experimentally and likely in the field. While heavy metals are frequently studied, there is weak evidence that they influence infection outcomes. Nitrogen and phosphorous do not appear to impact pathogen growth or infection in the amphibian host. The effects of other chemicals, like pesticides and disinfectants on infection were mostly unclear with mixed results or lacking an in vivo component. Our study shows that water chemistry does impact disease dynamics, but the effects of specific parameters require more investigation. Improving our understanding of how water chemistry influences disease dynamics will help predict the impact of chytridiomycosis, especially in amphibian populations affected by land use changes.


Assuntos
Anfíbios , Batrachochytrium , Qualidade da Água , Animais , Batrachochytrium/efeitos dos fármacos , Anfíbios/microbiologia , Micoses/microbiologia , Micoses/veterinária , Micoses/prevenção & controle , Salinidade , Fungicidas Industriais/farmacologia , Quitridiomicetos/efeitos dos fármacos , Quitridiomicetos/patogenicidade , Praguicidas/farmacologia , Desinfetantes/farmacologia , Antifúngicos/farmacologia
7.
PLoS One ; 19(5): e0301913, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38787834

RESUMO

Small lentic water bodies are important emitters of methane (CH4) and carbon dioxide (CO2), but the processes regulating their dynamics and susceptibility to human-induced stressors are not fully understood. Bioturbation by chironomid larvae has been proposed as a potentially important factor controlling the dynamics of both gases in aquatic sediments. Chironomid abundance can be affected by the application of biocides for mosquito control, such as Bti (Bacillus thuringiensis var. israelensis). Previous research has attributed increases in CH4 and CO2 emissions after Bti application to reduced bioturbation by chironomids. In this study, we separately tested the effect of chironomid bioturbation and Bti addition on CH4 production and emission from natural sediments. In a set of 15 microcosms, we compared CH4 and CO2 emission and production rates with high and low densities of chironomid larvae at the bioturbating stage, and standard and five times (5x) standard Bti dose, with control sediments that contained neither chironomid larvae nor Bti. Regardless of larvae density, chironomid larvae did not affect CH4 nor CO2 emission and production of the sediment, although both rates were more variable in the treatments with organisms. 5xBti dosage, however, led to a more than three-fold increase in CH4 and CO2 production rates, likely stimulated by bioavailable dissolved carbon in the Bti excipient and priming effects. Our results suggest weak effects of bioturbating chironomid larvae on the CH4 and CO2 dynamics in aquatic ecosystems. Furthermore, our results point out towards potential functional implications of Bti for carbon cycling beyond those mediated by changes in the macroinvertebrate community.


Assuntos
Dióxido de Carbono , Chironomidae , Água Doce , Sedimentos Geológicos , Larva , Metano , Animais , Chironomidae/metabolismo , Chironomidae/efeitos dos fármacos , Chironomidae/crescimento & desenvolvimento , Dióxido de Carbono/metabolismo , Dióxido de Carbono/farmacologia , Larva/efeitos dos fármacos , Larva/metabolismo , Metano/metabolismo , Sedimentos Geológicos/química , Bacillus thuringiensis/metabolismo , Desinfetantes/farmacologia , Controle de Mosquitos/métodos , Culicidae/efeitos dos fármacos , Culicidae/metabolismo
8.
Curr Microbiol ; 81(7): 198, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38819647

RESUMO

Although usefulness of masks for protection against respiratory pathogens, accumulation of pathogens on their surface represents a source of infection spread. Here we prepared a plant extract-based disinfecting layer to be used in coating masks thus inhibiting their capacity to transmit airborne pathogens. To reach this, a polypropylene membrane base was coated with a layer of polyvinyledine difluoride polymer containing 500 µg/ml of Camellia sinensis (Black tea) methanolic extract. Direct inhibitory effects of C. sinensis were initially demonstrated against Staphylococcus aureus (respiratory bacteria), influenza A virus (enveloped virus) and adenovirus 1 (non-enveloped virus) which were directly proportional to both extract concentration and incubation time with the pathogen. This was later confirmed by the capacity of the supplemented membrane with the plant extract to block infectivity of the above mentioned pathogens, recorded % inhibition values were 61, 72 and 50 for S. aureus, influenza and adenovirus, respectively. In addition to the disinfecting capacity of the membrane its hydrophobic nature and pore size (154 nm) prevented penetration of dust particles or water droplets carrying respiratory pathogens. In summary, introducing this layer could protect users from infection and decrease infection risk upon handling contaminated masks surfaces.


Assuntos
Camellia sinensis , Máscaras , Extratos Vegetais , Staphylococcus aureus , Camellia sinensis/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Staphylococcus aureus/efeitos dos fármacos , Máscaras/virologia , Desinfetantes/farmacologia , Vírus da Influenza A/efeitos dos fármacos , Humanos
9.
Sci Total Environ ; 934: 173210, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38750753

RESUMO

Controlling the dissemination of antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) is a global concern. While commonly used chlorine disinfectants can damage or even kill ARB, dissolved oxygen (DO) may affect the formation of reactive chlorine species. This leads to the hypothesis that DO may play roles in mediating the effectiveness of chlorine disinfection for antibiotic resistance. To this end, this study investigated the impacts of DO on the efficiency of chlorine disinfection for antibiotic resistance. The results revealed that DO could increase the inactivation efficiency of ARB under chloramine and free chlorine exposure at practically relevant concentrations. Reactive species induced by DO, including H2O2, O2-, and OH, inactivated ARB strains by triggering oxidative stress response and cell membrane damage. In addition, the removal efficiency of extracellular ARGs (i.e. tetA and blaTEM) was enhanced with increasing dosage of free chlorine or chloramine under aerobic conditions. DO facilitated the fragmentation of plasmids, contributing to the degradation of extracellular ARGs under exposure to chlorine disinfectants. The findings suggested that DO facilitates disinfection efficiency for antibiotic resistance in water treatment systems.


Assuntos
Cloro , Desinfetantes , Desinfecção , Oxigênio , Cloro/farmacologia , Desinfecção/métodos , Desinfetantes/farmacologia , Purificação da Água/métodos , Resistência Microbiana a Medicamentos/genética , Farmacorresistência Bacteriana/genética , Antibacterianos/farmacologia
10.
ACS Appl Mater Interfaces ; 16(21): 26998-27010, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38748642

RESUMO

A coating that can be activated by moisture found in respiratory droplets could be a convenient and effective way to control the spread of airborne pathogens and reduce fomite transmission. Here, the ability of a novel 6-hydroxycatechol-containing polymer to function as a self-disinfecting coating on the surface of polypropylene (PP) fabric was explored. Catechol is the main adhesive molecule found in mussel adhesive proteins. Molecular oxygen found in an aqueous solution can oxidize catechol and generate a known disinfectant, hydrogen peroxide (H2O2), as a byproduct. However, given the limited amount of moisture found in respiratory droplets, there is a need to enhance the rate of catechol autoxidation to generate antipathogenic levels of H2O2. 6-Hydroxycatechol contains an electron donating hydroxyl group on the 6-position of the benzene ring, which makes catechol more susceptible to autoxidation. 6-Hydroxycatechol-coated PP generated over 3000 µM of H2O2 within 1 h when hydrated with a small amount of aqueous solution (100 µL of PBS). The generated H2O2 was three orders of magnitude higher when compared to the amount generated by unmodified catechol. 6-Hydroxycatechol-containing coating demonstrated a more effective antimicrobial effect against both Gram-positive (Staphylococcus aureus and Staphylococcus epidermidis) and Gram-negative (Pseudomonas aeruginosa and Escherichia coli) bacteria when compared to unmodified catechol. Similarly, the self-disinfecting coating reduced the infectivity of both bovine viral diarrhea virus and human coronavirus 229E by as much as a 2.5 log reduction value (a 99.7% reduction in viral load). Coatings containing unmodified catechol did not generate sufficient H2O2 to demonstrate significant virucidal effects. 6-Hydroxycatechol-containing coating can potentially function as a self-disinfecting coating that can be activated by the moisture present in respiratory droplets to generate H2O2 for disinfecting a broad range of pathogens.


Assuntos
Catecóis , Peróxido de Hidrogênio , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/farmacologia , Catecóis/química , Catecóis/farmacologia , Humanos , Staphylococcus aureus/efeitos dos fármacos , Desinfetantes/farmacologia , Desinfetantes/química , Polipropilenos/química , Antibacterianos/farmacologia , Antibacterianos/química , Escherichia coli/efeitos dos fármacos
11.
J Food Prot ; 87(6): 100288, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38697484

RESUMO

Escherichia coli commonly found in the gastrointestinal tracts of food animals include Shiga toxin-producing E. coli (STEC, stx+, eae-), Enterohemorrhagic E. coli (EHEC, stx+, eae+), Enteropathogenic E. coli (EPEC, stx-, eae+), and "nondiarrheagenic" E. coli (NDEC, stx-, eae-). EHEC, EPEC, and STEC are associated with foodborne disease outbreaks. During meat processing, disinfectants are employed to control various bacteria, including human pathogens. Concerns exist that E. coli resistant to antibiotics are less susceptible to disinfectants used during meat processing. Since EHEC, EPEC, and STEC with reduced susceptibility to disinfectants are potential public health risks, the goal of this study was to evaluate the association of antibiotic resistant (ABR) E. coli with increased tolerance to 4% lactic acid (LA) and 150 ppm quaternary ammonium compounds (QACs). A pool of 3,367 E. coli isolated from beef cattle, veal calves, swine, and sheep at various processing stages was screened to identify ABR E. coli. Resistance to ≥1 of the six antibiotics examined was identified in 27.9%, 36.1%, 54.5%, and 28.7% among the NDEC (n = 579), EHEC (n = 693), EPEC (n = 787), and STEC (n = 1308) isolates evaluated, respectively. Disinfectant tolerance did not differ (P > 0.05) between ABR and antibiotic susceptible EHEC isolates. Comparable frequencies (P > 0.05) of biofilm formation or congo red binding were observed between ABR and antibiotic susceptible strains of E. coli. Understanding the frequencies of ABR and disinfectant tolerance among E. coli present in food-animal is a critically important component of meat safety.


Assuntos
Antibacterianos , Desinfetantes , Escherichia coli , Carne Vermelha , Desinfetantes/farmacologia , Animais , Escherichia coli/efeitos dos fármacos , Antibacterianos/farmacologia , Carne Vermelha/microbiologia , Humanos , Farmacorresistência Bacteriana , Testes de Sensibilidade Microbiana , Microbiologia de Alimentos , Contagem de Colônia Microbiana , Bovinos , Carne/microbiologia , Contaminação de Alimentos/análise
12.
Water Res ; 257: 121685, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38728774

RESUMO

Water disinfection is undoubtedly regarded as a critical step in ensuring the water safety for human consumption, and ozone is widely used as a highly effective disinfectant for the control of pathogenic microorganisms in water. Although the diminished ozone efficiencies in complex water matrices have been widely reported, the specific extent to which individual components of matrix act on the virus inactivation by ozone remains unclear, and effective methodologies to predict the comprehensive effects of various factors are needed. In this study, the decoupled impact of the intricate water matrix on the ozone inactivation of viruses was systematically investigated and assessed from a simulative perspective. The concept of "equivalent ozone depletion rate constant" (k') was introduced to quantify the influence of different species, and a kinetic model was developed based on the k' values for simulating the ozone inactivation processes in complex matrix. The mechanisms through which diverse species influenced the ozone inactivation effectiveness were identified: 1) competition effects (k' = 105∼107 M-1s-1), including organic matters and reductive ions (SO32-, NO2-, and I-), which were the most influential species inhibiting the virus inactivation; 2) shielding effects (k' = 103∼104 M-1s-1), including Ca2+, Mg2+, and kaolin; 3) insignificant effects (k' = 0∼1 M-1s-1), including Cl-, SO42-, NO3-, NH4+, and Br-; 4) promotion effects (k' = ∼-103 M-1s-1), including CO32- and HCO3-. Prediction of ozone disinfection efficiency and evaluation of species contribution under complex aquatic matrices were successfully realized utilizing the model. The systematic understanding and methodologies developed in this research provide a reliable framework for predicting ozone inactivation efficiency under complex matrix, and a potential tool for accurate disinfectant dosage determination and interfering factors control in actual wastewater treatment processes.


Assuntos
Desinfecção , Ozônio , Inativação de Vírus , Águas Residuárias , Ozônio/farmacologia , Águas Residuárias/virologia , Inativação de Vírus/efeitos dos fármacos , Desinfecção/métodos , Purificação da Água , Desinfetantes/farmacologia , Modelos Teóricos , Cinética
16.
J Water Health ; 22(3): 601-611, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38557574

RESUMO

Coronavirus disease 2019 (COVID-19) is an infectious viral disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that emerged at the end of 2019. SARS-CoV-2 can be transmitted through droplets, aerosols, and fomites. Disinfectants such as alcohol, quaternary ammonium salts, and chlorine-releasing agents, including hypochlorous acid, are used to prevent the spread of SARS-CoV-2 infection. In the present study, we investigated the efficacy of ionless hypochlorous acid water (HOCl) in suspension and by spraying to inactivate SARS-CoV-2. The virucidal efficacy of HOCl solution in tests against SARS-CoV-2 was evaluated as 50% tissue culture infectious dose. Although the presence of organic compounds influenced the virucidal efficacy, HOCl treatment for 20 s was significantly effective to inactivate Wuhan and Delta strains in the suspension test. HOCl atomization for several hours significantly reduced the SARS-CoV-2 attached to plastic plates. These results indicate that HOCl solution with elimination containing NaCl and other ions may have high virucidal efficacy against SARS-CoV-2. This study provides important information about the virucidal efficacy and use of HOCl solution.


Assuntos
COVID-19 , Desinfetantes , Humanos , SARS-CoV-2 , COVID-19/prevenção & controle , Ácido Hipocloroso/farmacologia , Água , Desinfetantes/farmacologia
17.
Sci Rep ; 14(1): 9159, 2024 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-38644372

RESUMO

Different strains of Escherichia coli that exhibit genetic characteristics linked to diarrhea pose a major threat to both human and animal health. The purpose of this study was to determine the prevalence of pathogenic Escherichia coli (E. coli), the genetic linkages and routes of transmission between E. coli isolates from different animal species. The efficiency of disinfectants such as hydrogen peroxide (H2O2), Virkon®S, TH4+, nano zinc oxide (ZnO NPs), and H2O2-based zinc oxide nanoparticles (H2O2/ZnO NPs) against isolated strains of E. coli was evaluated. Using 100 fecal samples from different diarrheal species (cow n = 30, sheep n = 40, and broiler chicken n = 30) for E. coli isolation and identification using the entero-bacterial repetitive intergenic consensus (ERIC-PCR) fingerprinting technique. The E. coli properties isolated from several diarrheal species were examined for their pathogenicity in vitro. Scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM), Fourier-transform infrared spectrum (FT-IR), X-ray diffraction (XRD), zeta potential, and particle size distribution were used for the synthesis and characterization of ZnO NPs and H2O2/ZnO NPs. The broth macro-dilution method was used to assess the effectiveness of disinfectants and disinfectant-based nanoparticles against E. coli strains. Regarding the results, the hemolytic activity and Congo red binding assays of pathogenic E. coli isolates were 55.3 and 44.7%, respectively. Eleven virulent E. coli isolates were typed into five ERIC-types (A1, A2, B1, B2, and B3) using the ERIC-PCR method. These types clustered into two main clusters (A and B) with 75% similarity. In conclusion, there was 90% similarity between the sheep samples' ERIC types A1 and A2. On the other hand, 89% of the ERIC types B1, B2, and B3 of cows and poultry samples were comparable. The H2O2/ZnO NPs composite exhibits potential antibacterial action against E. coli isolates at 0.04 mg/ml after 120 min of exposure.


Assuntos
Galinhas , Diarreia , Desinfetantes , Infecções por Escherichia coli , Escherichia coli , Peróxido de Hidrogênio , Óxido de Zinco , Animais , Óxido de Zinco/farmacologia , Óxido de Zinco/química , Peróxido de Hidrogênio/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Diarreia/microbiologia , Diarreia/veterinária , Galinhas/microbiologia , Desinfetantes/farmacologia , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/veterinária , Ovinos , Bovinos , Nanopartículas/química , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/prevenção & controle , Fezes/microbiologia , Nanopartículas Metálicas/química
18.
Environ Sci Technol ; 58(15): 6552-6563, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38571383

RESUMO

Extracellular polymeric substances (EPS) ubiquitously encapsulate microbes and play crucial roles in various environmental processes. However, understanding their complex interactions with dynamic bacterial behaviors, especially during the disinfection process, remains very limited. In this work, we investigated the impact of EPS on bacterial disinfection kinetics by developing a permanent EPS removal strategy. We genetically disrupted the synthesis of exopolysaccharides, the structural components of EPS, in Pseudomonas aeruginosa, a well-known EPS-producing opportunistic pathogen found in diverse environments, creating an EPS-deficient strain. This method ensured a lasting absence of EPS while maintaining bacterial integrity and viability, allowing for real-time in situ investigations of the roles of EPS in disinfection. Our findings indicate that removing EPS from bacteria substantially lowered their susceptibility threshold to disinfectants such as ozone, chloramine B, and free chlorine. This removal also substantially accelerated disinfection kinetics, shortened the resistance time, and increased disinfection efficiency, thereby enhancing the overall bactericidal effect. The absence of EPS was found to enhance bacterial motility and increase bacterial cell vulnerability to disinfectants, resulting in greater membrane damage and intensified reactive oxygen species (ROS) production upon exposure to disinfectants. These insights highlight the central role of EPS in bacterial defenses and offer promising implications for developing more effective disinfection strategies.


Assuntos
Desinfetantes , Desinfecção , Desinfecção/métodos , Matriz Extracelular de Substâncias Poliméricas , Desinfetantes/farmacologia , Cloro/farmacologia , Cinética
19.
J Appl Microbiol ; 135(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38573833

RESUMO

In the 1940s and 1950s, researchers seeking safe and novel ways to eliminate airborne pathogens from enclosed spaces, investigated glycol vapours as a method of disinfection. More recently, the COVID-19 pandemic highlighted the need for a non-toxic aerial disinfectant that can be used in the presence of people. This scoping review is intended to analyse the early and more recent literature on glycol disinfection, scrutinizing the methodologies used, and to determine if the use of glycols as modern-day disinfectants is justified PRISMA-ScR guidelines were used to assess the 749 articles retrieved from the Web of Science platform, with 46 articles retained after the search strategy was applied. Early studies generally demonstrated good disinfection capabilities against airborne bacteria and viruses, particularly with propylene glycol (PG) vapour. Vapour pressure, relative humidity, and glycol concentration were found to be important factors affecting the efficacy of glycol vapours. Contact times depended mainly on the glycol application method (i.e. aerosolization or liquid formulation), although information on how glycol efficacy is impacted by contact time is limited. Triethylene glycol (TEG) is deemed to have low toxicity, carcinogenicity, and mutagenicity and is registered for use in air sanitization and deodorization by the US Environmental Protection Agency. Glycols are also used in liquid formulations for their antimicrobial activity against a wide range of microorganisms, although when used as a non-active excipient in products, their contribution to antimicrobial efficacy is rarely assessed. The appropriate use of liquid glycol-containing formulations was found to positively impact the antimicrobial capabilities of disinfectants when used at temperatures <0, food preservatives, and dental medicaments. Providing modern delivery technology can accurately control environmental conditions, the use of aerosolized glycol formulations should lead to successful disinfection, aiding infection prevention, and control regimens.


Assuntos
Anti-Infecciosos , Desinfetantes , Humanos , Pandemias/prevenção & controle , Desinfetantes/farmacologia , Desinfecção/métodos , Anti-Infecciosos/farmacologia , Propilenoglicol/farmacologia , Gases
20.
Environ Sci Technol ; 58(15): 6793-6803, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38574343

RESUMO

Current disinfection processes pose an emerging environmental risk due to the ineffective removal of antibiotic-resistant bacteria, especially disinfection residual bacteria (DRB) carrying multidrug-resistant plasmids (MRPs). However, the characteristics of DRB-carried MRPs are poorly understood. In this study, qPCR analysis reveals that the total absolute abundance of four plasmids in postdisinfection effluent decreases by 1.15 log units, while their relative abundance increases by 0.11 copies/cell compared to investigated wastewater treatment plant (WWTP) influent. We obtain three distinctive DRB-carried MRPs (pWWTP-01-03) from postdisinfection effluent, each carrying 9-11 antibiotic-resistant genes (ARGs). pWWTP-01 contains all 11 ARGs within an ∼25 Kbp chimeric genomic island showing strong patterns of recombination with MRPs from foodborne outbreaks and hospitals. Antibiotic-, disinfectant-, and heavy-metal-resistant genes on the same plasmid underscore the potential roles of disinfectants and heavy metals in the coselection of ARGs. Additionally, pWWTP-02 harbors an adhesin-type virulence operon, implying risks of both antibiotic resistance and pathogenicity upon entering environments. Furthermore, some MRPs from DRB are capable of transferring and could confer selective advantages to recipients under environmentally relevant antibiotic pressure. Overall, this study advances our understanding of DRB-carried MRPs and highlights the imminent need to monitor and control wastewater MRPs for environmental security.


Assuntos
Desinfetantes , Purificação da Água , Desinfecção , Genes Bacterianos , Bactérias/genética , Antibacterianos/farmacologia , Desinfetantes/farmacologia , Plasmídeos/genética
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