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AIMS: Herpes simplex virus type 1 (HSV-1) is an enveloped virus that causes recurrent and incurable diseases in 67% of the world population. Although it is not listed as a foodborne virus, some studies have shown that it can be recovered from surfaces as well as food. METHODS AND RESULTS: We investigated its persistence at -20°C, 4°C, 20°C, or 37°C for up to 7 days on stainless steel, aluminum, glass, polypropylene, cheddar cheese, sliced almond, and apple skin and in cola soft drink, orange juice, coffee, and milk, as well as its transferability from stainless steel to dry or moistened nitrile or latex gloves over time at typical ambient temperatures. Based on the plaque assay on Vero cells, HSV-1 persisted at least 24 h on all surfaces and at least 1 h on food matrices but was inactivated quickly in cola soft drink. Temperature and pH affected HSV-1 infectivity. Transfer of HSV-1 at a contact pressure of 1 kg cm2-1 for 10 s occurred only on latex, especially moistened. CONCLUSIONS: Our data on the persistence of HSV-1 on food-related surfaces suggest that some risk may be associated with sharing foods with infected carriers.
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Herpesvirus Humano 1 , Manipulação de Alimentos/métodos , Látex , Aço Inoxidável , Células Vero , HumanosRESUMO
The formation of biofilms in dairy processing plants can reduce equipment efficiency, contribute to surface deterioration, and contaminate dairy products by releasing the microorganisms they contain, which may cause spoilage or disease. However, a more representative identification of microbial communities and physico-chemical characterization requires to detach and recover adequately the entire biofilm from the surface. The aim of this study is to develop an efficient technique for in-plant biofilm sampling by growing a strain of Pseudomonas azotoformans PFl1A on stainless-steel surface in a dynamic CDC biofilm reactor system using tryptic soy broth (TSB) and milk as growth media. Different techniques, namely, swabbing, scraping, sonic brushing, synthetic sponge, and sonicating synthetic sponge were used and the results were compared to a standard ASTM International method using ultrasonication. Their efficiencies were evaluated by cells enumeration and scanning electron microscopy. The maximum total viable counts of 8.65 ± 0.06, 8.75 ± 0.08, and 8.71 ± 0.09 log CFU/cm2 were obtained in TSB medium using scraping, synthetic sponge, and sonicating synthetic sponge, respectively, which showed no statistically significant differences with the standard method, ultrasonication (8.74 ± 0.02 log CFU/cm2). However, a significantly (p < 0.05) lower cell recovery of 8.57 ± 0.10 and 8.60 ± 0.00 log CFU/cm2 compared to ultrasonication were achieved for swabbing and sonic brushing, respectively. Furthermore, scanning electron microscopy showed an effective removal of biofilms by sonic brushing, synthetic sponge, and sonicating synthetic sponge; However, only the latter two methods guaranteed a superior release of bacterial biofilm into suspension. Nevertheless, a combination of sonication and synthetic sponge ensured dislodging of sessile cells from surface crevices. The results suggest that a sonicating synthetic sponge could be a promising method for biofilm recovery in processing plants, which can be practically used in the dairy industries as an alternative to ultrasonication.
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Due to rising consumer preference for natural remedies, the search for natural antiviral agents has accelerated considerably in recent years. Among the natural sources of compounds with potential antiviral proprieties, berries are interesting candidates, due to their association with health-promoting properties, including antioxidant, antimutagenic, anticancer, antimicrobial, anti-inflammatory, and neuroprotective properties. The past two decades have witnessed a flurry of new findings. Studies suggest promising antiviral proprieties against enveloped and non-enveloped viruses, particularly of cranberries, blueberries, blackcurrants, black raspberries, and pomegranates. The aim of this review is to assemble these findings, to list the implied mechanisms of action, and thereby point out promising subjects for research in this field, in the hope that compounds obtainable from natural sources such as berries may be used someday to treat, or even prevent, viral infections.
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The emergence of the SARS-CoV-2 infection and its potential transmission through touching surfaces in clinical environments have impelled the use of conventional and novel methods of disinfection to prevent its spreading. Among the latter, pulsed light may be an effective, non-chemical decontamination alternative. Pulsed light technology inactivates microorganisms and viruses by using high intensity polychromatic light pulses, which degrades nucleic acids and proteins. This review describes this technology, compiles and critically analyzes the evidence about the virucidal efficacy of pulsed light technology with view on its potential use against SARS-CoV-2 in touching surfaces in health-care facilities. The efficacy of pulsed light proved against many different kind of viruses allows to conclude that is a suitable candidate to inactivate SARS-CoV-2 as long as the required fluence is applied and the appropriated exposure to contaminated surfaces is guaranteed.
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COVID-19/prevenção & controle , Controle de Infecções/métodos , Luz , SARS-CoV-2/efeitos da radiação , Animais , COVID-19/transmissão , Hospitais , HumanosRESUMO
We designed and synthesised a series of novel chalcones, incorporating the heterocyclic framework of 2,2-dimethyl-2,3-dihydro-4(1H)-quinolinone, which was prepared via Sonogashira coupling of a substituted orthoaniline under aqueous conditions using Pd catalysis followed by acid-mediated cyclisation. The compounds were screened against the NCI-N87 and DLD-1 cancer cell lines, with most compounds showing low micromolar cytotoxic activity.
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Outbreaks of foodborne illness associated with berries often involve contamination with hepatitis A virus (HAV) and norovirus but also bacteria such as Escherichia coli O157:H7 and parasites such as Cyclospora caytanensis. We evaluated the applicability of UV-C to the inactivation of pathogens on strawberries, raspberries and blueberries. Our three-step approach consisted of assessing the chemical safety of UV-C-irradiated berries, evaluating the sensory quality after UV-C treatment and finally studying the inactivation of the target microorganisms. Treatments lasting up to 9â¯min (4000â¯mJâ¯cm-2) did not produce detectable levels of furan (<5⯵g/kg), a known photolysis product of fructose with genotoxic activity and thus were assessed to be toxicologically safe. No effect on taste or appearance was observed, unless treatment was excessively long. 20â¯s of treatment (an average fluence of ~ 212â¯mJâ¯cm-2) reduced active HAV titer by >1 log10 unit in 95% of cases except on frozen raspberries, while 120â¯s were required to inactivate murine norovirus to this extent on fresh blueberries. The mean inactivation of HAV and MNV was greater on blueberries (2-3 log10) than on strawberries and raspberries (<2 log10). MNV was more sensitive on fresh than on frozen berries, unlike HAV. Inactivation of Salmonella, E. coli O157:H7 and Listeria monocytogenes was poor on all three berries, no treatment reducing viable counts by >1 log10 unit. In most matrices, prolonging the treatment did not improve the result to any significant degree. The effect was near its plateau after 20â¯s of treatment. These results provide insight into the effectiveness of UV-C irradiation for inactivating bacterial and viral pathogens and surrogates on fresh and frozen berries having different surface types, under different physical conditions and at different levels of contamination. Overall they show that UV-C as single processing step is unsuitable to inactivate significant numbers of foodborne pathogens on berries.
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Mirtilos Azuis (Planta)/microbiologia , Irradiação de Alimentos/métodos , Doenças Transmitidas por Alimentos/prevenção & controle , Fragaria/microbiologia , Frutas/microbiologia , Viabilidade Microbiana/efeitos da radiação , Rubus/microbiologia , Animais , Escherichia coli O157/efeitos da radiação , Microbiologia de Alimentos , Congelamento , Vírus da Hepatite A/efeitos da radiação , Listeria monocytogenes/efeitos da radiação , Norovirus/efeitos da radiação , Salmonella/efeitos da radiação , Raios UltravioletaRESUMO
Electro-activation was used to add value to sweet defatted whey. This study aimed to investigate and to characterize the bioactive compounds formed under different electro-activation conditions by molecular and proteomic approaches. The effects of electric current intensity (400, 500 or 600mA) and whey concentration (7, 14 or 21% (w/v)) as a function of the electro-activation time (0, 15, 30 or 45min) were evaluated. The targeted dependent variables were the formation of Maillard reaction products (MRPs), protein hydrolysates and glycated compounds. It was shown that the MRPs derived from electro-activated whey at a concentration of 14% had the highest potential of biological activity. SDS-PAGE analyses indicated the formation of hydrolysates and glycated compounds with different molecular weight distributions. FTIR indicated the predominance of intermediate MRPs, such as the Schiff base compounds. LC-MS/MS and proteomics analysis showed the production of multi-functional bioactive peptides due to the hydrolysis of whey proteins.
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Reação de Maillard , Peptídeos/química , Proteínas do Soro do Leite/química , Soro do Leite/químicaRESUMO
This study was conducted to evaluate the inactivation of murine norovirus (MNV-1) and hepatitis A virus (HAV) by pulsed ultraviolet (UV) light. MNV-1 was used as a model for human norovirus. Viral suspensions of about 10(6) PFU/ml were exposed to pulses of UV light for different times and at different distances in a Xenon Steripulse device (model RS-3000C). Inactivation studies were also carried out on 1-cm(2) stainless steel and polyvinyl chloride disks with 10(5) PFU/ml. Inactivation of MNV-1 and HAV at 10.5 cm from the UV source was greater on inert surfaces than in suspension. The presence of organic matter (fetal bovine serum) reduced the effectiveness of pulsed light both in suspension and on surfaces. However, 2-s treatment in the absence of FBS completely inactivated (5 log reduction) the viral load at different distances tested, whether in suspension (MNV-1) or on disks (MNV-1 and HAV). The same treatment in the presence of fetal bovine serum (5%) allowed a reduction of about 3 log. This study showed that short duration pulses represent an excellent alternative for inactivation of food-borne viruses. This technology could be used to inactivate viruses in drinking water or on food-handling surfaces.
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Desinfecção/métodos , Contaminação de Alimentos/prevenção & controle , Irradiação de Alimentos , Vírus da Hepatite A/crescimento & desenvolvimento , Norovirus/crescimento & desenvolvimento , Inativação de Vírus , Animais , Contaminação de Alimentos/análise , Vírus da Hepatite A/efeitos da radiação , Humanos , Camundongos , Norovirus/efeitos da radiação , Cloreto de Polivinila , Aço Inoxidável , Raios UltravioletaRESUMO
The aims of this study were (i) to evaluate the impact of pH and relative humidity on the attachment of norovirus (NoV) to fomites and (ii) to evaluate the effectiveness of different household disinfectants on NoV attached to fomites. Plaque assay and/or real-time reverse transcription PCR assay were used to determine the amount of murine and human NoV attached to stainless steel disks, i.e., the amount removed by sonication in elution buffer but not by surface rinses with water only. An enzymatic pretreatment was used for both human and murine NoV before the real-time reverse transcription PCR assay to avoid detection of RNA associated with inactivated virus. For both murine and human NoV, maximum attachment was obtained after a contact time of 10 min. Attachment of NoV to stainless steel does not appear to be affected by pH, although murine NoV was less attached (<2 log units) at pH 9 and at low relative humidity (25%) than was human NoV (3 log units). Sodium hypochlorite (3%) was the most effective disinfectant, producing a greater than 3-log reduction after 10 min compared with less than a 1-log reduction after treatment with quaternary ammonium compounds and ethoxylated alcohols. Murine NoV was more sensitive than human NoV to disinfectants by approximately 1 to 2 log units. These results will help improve strategies for decontaminating surfaces harboring NoV and thus reduce the incidence of illness caused by these pathogens in the food sector and domestic environments.