Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
Mais filtros











Intervalo de ano de publicação
1.
Artigo em Inglês | MEDLINE | ID: mdl-32899803

RESUMO

The COVID-19 infection, caused by SARS-CoV-2, is inequitably distributed and more lethal among populations with lower socioeconomic status. Direct contact with contaminated surfaces has been among the virus sources, as it remains infective up to days. Several disinfectants have been shown to inactivate SARS-CoV-2, but they rapidly evaporate, are flammable or toxic and may be scarce or inexistent for vulnerable populations. Therefore, we are proposing simple, easy to prepare, low-cost and efficient antiviral films, made with a widely available dishwashing detergent, which can be spread on hands and inanimate surfaces and is expected to maintain virucidal activity for longer periods than the current sanitizers. Avian coronavirus (ACoV) was used as model of the challenge to test the antivirus efficacy of the proposed films. Polystyrene petri dishes were covered with a thin layer of detergent formula. After drying, the films were exposed to different virus doses for 10 min and virus infectivity was determined using embryonated chicken eggs, and RNA virus quantification in allantoic fluids by RT-qPCR. The films inactivated the ACoV (ranging from 103.7 to 106.7 EID50), which is chemically and morphologically similar to SARS-CoV-2, and may constitute an excellent alternative to minimize the spread of COVID-19.


Assuntos
Desinfetantes , Gammacoronavirus/efeitos dos fármacos , Inativação de Vírus , Animais , Betacoronavirus/efeitos dos fármacos , COVID-19 , Galinhas , Infecções por Coronavirus/prevenção & controle , Humanos , Óvulo/virologia , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , SARS-CoV-2
2.
J Sci Food Agric ; 100(6): 2321-2326, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31821568

RESUMO

Edible kernels have been popular food items since ancient times. Although in-shell nuts are naturally protected and relatively shelf stable, convenience demands require their commercialization in shelled form. However, whereas shelled kernels are more convenient, they are more exposed to oxygen, and thus more susceptible to oxidative rancidity and loss of crunchiness, which negatively affect the product acceptability. In this review, we discuss the role of edible coatings in extending stability of edible kernels, which is an opportunity to be better explored by the industry. The discussion also includes the role of antioxidants in the context of active coatings. Finally, future prospects and research challenges are addressed. © 2019 Society of Chemical Industry.


Assuntos
Filmes Comestíveis , Nozes , Sementes , Antioxidantes , Manipulação de Alimentos/métodos , Conservação de Alimentos/métodos , Lipídeos/química , Oxirredução
3.
Ciênc. rural (Online) ; 49(10): e20190310, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1045253

RESUMO

ABSTRACT: During the shelf-life of fresh meat, physical, chemical, microbiological, and sensory changes may occur. To avoid such changes, the combination of vacuum-packaging and use of edible coatings make a good strategy. This study aimed to evaluate the physicochemical characteristics of vacuum-packaged lamb meat combined with different zein-based edible coatings containing different vegetable oils (pink pepper, rosemary, olive oil, and the combinations of olive oil + pink pepper or rosemary), stored at 5 ± 1 °C. Parameters including pH, instrumental color, water holding capacity (WHC), shear force, and thiobarbituric acid reactive substances (TBARS) were analyzed every seven days, for 29 days. Significant differences (P<0.05) were observed in coating effects and storage time. The combination of olive oil and pepper oil (OLPP) exhibited higher color stability, while the coatings containing rosemary (RO), rosemary and olive oil (OLRO), and pink pepper oil (PP) exhibited the highest oxidative stability in 29 days. The pH, WHC, and shear force parameters did not appear to have been affected by the coatings. In summary, as appearance is an important purchasing factor, the coating containing olive oil and pink pepper oil is very promising as an alternative for maintaining vacuum-packaged lamb meat quality.


RESUMO: Durante a vida de prateleira da carne fresca podem ocorrer mudanças físico-químicas, microbiológicas e sensoriais indesejadas. Para evitar tais mudanças a combinação da embalagem tradicional à vácuo com revestimentos comestíveis é uma alternativa. O objetivo deste estudo foi avaliar o efeito do uso de diferentes revestimentos comestíveis à base de zeínas em combinação com diferentes óleos vegetais (óleos de: pimenta rosa, alecrim, azeite e combinação de azeite + óleo de pimenta rosa ou alecrim) nas características fisico-químicas da carne ovina, embalada à vácuo e armazenada à temperatura 5±1 °C. Foram realizadas análises de pH, cor instrumental, capacidade de retenção de água (CRA), força de cisalhamento, substâncias reativas ao ácido tiobarbitúrico (TBARS) a cada sete dias, no período de 29 dias. Foram observadas diferenças significativas (P<0,05) para o efeito de revestimentos e o tempo de armazenamento. A combinação de azeite mais óleo de pimenta (OLPP), apresentou maior estabilidade de cor, enquanto que os revestimentos contendo alecrim (RO), alecrim mais azeite (OLRO) e óleo de pimenta (PP) foram os que apresentaram maior estabilidade oxidativa no período de 29 dias. Os parâmetros pH, CRA e força de cisalhamento não parecem ter sido afetados pelos revestimentos. Tendo em vista que aparência é um importante fator de compra, o revestimento contendo azeite e óleo de pimenta rosa foi o mais promissor para ser utilizado na manutenção da qualidade de carne ovina.

4.
Ci. Rural ; 49(10): e20190310, 2019. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-23984

RESUMO

During the shelf-life of fresh meat, physical, chemical, microbiological, and sensory changes may occur. To avoid such changes, the combination of vacuum-packaging and use of edible coatings make a good strategy. This study aimed to evaluate the physicochemical characteristics of vacuum-packaged lamb meat combined with different zein-based edible coatings containing different vegetable oils (pink pepper, rosemary, olive oil, and the combinations of olive oil + pink pepper or rosemary), stored at 5 ± 1 °C. Parameters including pH, instrumental color, water holding capacity (WHC), shear force, and thiobarbituric acid reactive substances (TBARS) were analyzed every seven days, for 29 days. Significant differences (P<0.05) were observed in coating effects and storage time. The combination of olive oil and pepper oil (OLPP) exhibited higher color stability, while the coatings containing rosemary (RO), rosemary and olive oil (OLRO), and pink pepper oil (PP) exhibited the highest oxidative stability in 29 days. The pH, WHC, and shear force parameters did not appear to have been affected by the coatings. In summary, as appearance is an important purchasing factor, the coating containing olive oil and pink pepper oil is very promising as an alternative for maintaining vacuum-packaged lamb meat quality.(AU)


Durante a vida de prateleira da carne fresca podem ocorrer mudanças físico-químicas, microbiológicas e sensoriais indesejadas. Para evitar tais mudanças a combinação da embalagem tradicional à vácuo com revestimentos comestíveis é uma alternativa. O objetivo deste estudo foi avaliar o efeito do uso de diferentes revestimentos comestíveis à base de zeínas em combinação com diferentes óleos vegetais (óleos de: pimenta rosa, alecrim, azeite e combinação de azeite + óleo de pimenta rosa ou alecrim) nas características fisico-químicas da carne ovina, embalada à vácuo e armazenada à temperatura 5±1 °C. Foram realizadas análises de pH, cor instrumental, capacidade de retenção de água (CRA), força de cisalhamento, substâncias reativas ao ácido tiobarbitúrico (TBARS) a cada sete dias, no período de 29 dias. Foram observadas diferenças significativas (P<0,05) para o efeito de revestimentos e o tempo de armazenamento. A combinação de azeite mais óleo de pimenta (OLPP), apresentou maior estabilidade de cor, enquanto que os revestimentos contendo alecrim (RO), alecrim mais azeite (OLRO) e óleo de pimenta (PP) foram os que apresentaram maior estabilidade oxidativa no período de 29 dias. Os parâmetros pH, CRA e força de cisalhamento não parecem ter sido afetados pelos revestimentos. Tendo em vista que aparência é um importante fator de compra, o revestimento contendo azeite e óleo de pimenta rosa foi o mais promissor para ser utilizado na manutenção da qualidade de carne ovina.(AU)


Assuntos
Produtos da Carne/análise , Embalagem de Alimentos/métodos , Zeína/análise , Óleos de Plantas/análise , Fenômenos Químicos , Ovinos
5.
Biomed Mater Eng ; 29(1): 29-42, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29254071

RESUMO

INTRODUCTION: Burn injuries represent a high risk of morbidity and mortality. The wound healing process is complex and requires the participation of different types of cells. Therefore, new biomaterials, which innovate the wound healing process, are being investigated. OBJECTIVE: The aim of this study was to investigate the use of bacterial cellulose both in its pure state and enriched with lidocaine in full-thickness burns in rats. METHODS: Thirty rats (Wistar) (260 ± 20 gramas) divided into control group (CG), bacterial cellulose membrane group (MG) and bacterial cellulose membrane enriched with lidocaine group (MLG) were used. The burns were induced using a 150°C heated soldering iron, held on the animal neck for 10 seconds. The biomaterial was applied immediately after injury and skin samples were collected on the tenth day of the treatment. The level of significance of p⩽0.05 was used for the conclusion of the statistical analysis. RESULTS: The groups treated with the biomaterials, a histological pattern compatible with a more advanced repair stage showing skin appendages, mild inflammatory infiltrate, better collagen fiber organization and mild immunostaining COX-2 and MMP-9 was observed, when compared to the control group that did not receive any type of treatment. CONCLUSION: Thus, was concluded that the bacterial cellulose-based biomaterial both in its pure state and enriched with lidocaine optimizing the full-thickness burn wound healing in rats.


Assuntos
Materiais Biocompatíveis/uso terapêutico , Curativos Biológicos , Queimaduras/terapia , Celulose/uso terapêutico , Polissacarídeos Bacterianos/uso terapêutico , Anestésicos Locais/uso terapêutico , Animais , Materiais Biocompatíveis/química , Queimaduras/patologia , Celulose/química , Lidocaína/uso terapêutico , Masculino , Membranas Artificiais , Polissacarídeos Bacterianos/química , Ratos Wistar , Pele/efeitos dos fármacos , Pele/patologia , Cicatrização/efeitos dos fármacos
6.
Anal Bioanal Chem ; 408(14): 3875-9, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27068694

RESUMO

High-resolution (13)C solid-state NMR stands out as one of the most promising techniques to solve the structure of insoluble proteins featuring biological and technological importance. The simplest nuclear magnetic resonance (NMR) spectroscopy method to quantify the secondary structure of proteins uses the areas of carbonyl and alpha carbon peaks. The quantification obtained by fitting procedures depends on the assignment of the peaks to the structure, type of line shape, number of peaks to be used, and other parameters that are set by the operator. In this paper, we demonstrate that the analysis of (13)C NMR spectra by a pattern recognition method-based on the singular value decomposition (SVD) regression, which does not depend on the operator-shows higher correlation coefficients for α-helix and ß-sheet (0.96 and 0.91, respectively) than Fourier transform infrared spectroscopy (FTIR) method. Therefore, the use of (13)C solid-state NMR spectra and SVD is a simple and reliable method for quantifying the secondary structures of insoluble proteins in solid-state.


Assuntos
Espectroscopia de Ressonância Magnética Nuclear de Carbono-13/métodos , Isótopos de Carbono , Estrutura Secundária de Proteína , Espectroscopia de Infravermelho com Transformada de Fourier
7.
Anal Bioanal Chem ; 393(4): 1357-60, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19043697

RESUMO

High intake of saturated fat from meats has been associated with cardiovascular disease, cancer, diabetes, and others diseases. In this paper, we are introducing a simple, high-throughput, and non-destructive low-resolution nuclear magnetic resonance method that has the potential to analyze the intramuscular fat content (IMF) in more than 1,000 beef portions per hour. The results can be used in nutritional fact labels, replacing the currently used average value. The method is based on longitudinal (T(1)) and transverse (T(2)) relaxation time information obtained by a continuous wave-free precession (CWFP) sequence. CWFP yields a higher correlation coefficient (r = 0.9) than the conventional Carr-Purcell-Meiboom-Gill (CPMG) method (r = -0.25) for IMF in beef and is just as fast and a simpler pulse sequence than CPMG. The method can also be applied to other meat products.


Assuntos
Tecido Adiposo/química , Espectroscopia de Ressonância Magnética/métodos , Músculo Esquelético/química , Animais , Composição Corporal , Bovinos
8.
Hig. aliment ; 22(160): 99-105, abr. 2008. tab
Artigo em Português | VETINDEX | ID: vti-14786

RESUMO

Filmes processados a partir de polímeros naturais não tóxicos têm se firmado como uma nova categoria de materiais de alto potencial, para aplicação como revestimentos protetores comestíveis sobre frutos e legumes, principalmente produtos minimamente processados. Esses revestimentos podem ser hidrofílicos ou hidrofóbicos e têm como principal finalidade reduzir a atividade respiratória, preservando por um período maior de tempo suas características fisiológicas. Neste trabalho apresentamos uma visão geral do processamento e atuação dessas coberturas. Como exemplo ilustrativo, filmes hidrofílicos e hidrofóbicos foram aplicados sobre maçãs fatiadas. O primeiro a partir de quitosana, um polissacarídeo hidrofílico de origem animal e o segundo, baseado em formulações a base de zeínas, proteínas hidrofóbicas de reserva do milho. Além de detalhes de preparação dos géis precursores, resultados com respeito à perda de massa e taxa de redução de fungos sobre superfícies são apresentadas.(AU)


Films processed from natural and non-toxic polymers have been considered a new category of materials for potential applications as protective coatings on fruits and vegetables, mainly for minimally processed products. Such coatings can be either hydrophilic or hydrophobic and the main aim is to reduce the fruit' s respiratory activity, therefore increasing its original physiological characteristics. These materials limit the respiration, have activity against browning, which are common on processed 'fruits, and also presentsome antimicrobial activity against bacteria and fungi, reducing microorganism proliferation over the cut surfaces. In this work an overview of the general film processing and features of these films arepresented. As illustrative example, hydrophilic and hydrophobic coatings are applied on cut apples. The first obtained from chitosan, a hydrophilic polysaccharide from animal origin; the second, a formulation based on zeins, storage proteins from maze. Gel details preparation and results concerning mass lost and fungi reduction on the surfaces is also presented. (AU)


Assuntos
Frutas , Conservantes de Alimentos , Qualidade dos Alimentos
9.
Hig. aliment ; 22(160): 99-105, abr. 2008. tab
Artigo em Português | LILACS | ID: lil-531972

RESUMO

Filmes processados a partir de polímeros naturais não tóxicos têm se firmado como uma nova categoria de materiais de alto potencial, para aplicação como revestimentos protetores comestíveis sobre frutos e legumes, principalmente produtos minimamente processados. Esses revestimentos podem ser hidrofílicos ou hidrofóbicos e têm como principal finalidade reduzir a atividade respiratória, preservando por um período maior de tempo suas características fisiológicas. Neste trabalho apresentamos uma visão geral do processamento e atuação dessas coberturas. Como exemplo ilustrativo, filmes hidrofílicos e hidrofóbicos foram aplicados sobre maçãs fatiadas. O primeiro a partir de quitosana, um polissacarídeo hidrofílico de origem animal e o segundo, baseado em formulações a base de zeínas, proteínas hidrofóbicas de reserva do milho. Além de detalhes de preparação dos géis precursores, resultados com respeito à perda de massa e taxa de redução de fungos sobre superfícies são apresentadas.


Assuntos
Conservantes de Alimentos , Qualidade dos Alimentos , Frutas
10.
Anal Chim Acta ; 596(2): 325-9, 2007 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-17631114

RESUMO

Oilseeds with modified fatty acid profiles have been the genetic alternative for high quality vegetable oil for food and biodiesel applications. They can provide stable, functional oils for the food industry, without the hydrogenation process that produces trans-fatty acid, which has been linked to cardiovascular disease. High yield and high quality oilseeds are also necessary for the success of biodiesel programs, as polyunsaturated or saturated fatty acid oil produces biofuel with undesirable properties. In this paper, a rapid and automated low resolution NMR method to select intact oilseeds with a modified fatty acid profile is introduced, based on 1H transverse relaxation time (T2). The T2 weighted NMR signal, obtained by a CPMG pulse sequence and processed by chemometric methods was able to determine the oil quality in intact seeds by its fatty composition, cetane number, iodine value and kinematic viscosity with a correlation coefficient r > 0.9. The automated system has the potential to analyze more than 1000 samples per hour and is a powerful tool to speed up the selection of high quality oilseeds for food and biodiesel applications.


Assuntos
Espectroscopia de Ressonância Magnética/métodos , Óleos de Plantas/análise , Sementes , Ácidos Graxos/análise , Ácidos Graxos/química , Sementes/química , Fatores de Tempo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA