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1.
Crit Rev Food Sci Nutr ; 63(31): 10899-10927, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35687346

RESUMO

Yeast selection for the wine industry in Spain started in 1950 for the understanding of the microbial ecology, and for the selection of optimal strains to improve the performance of alcoholic fermentation and the overall wine quality. This process has been strongly developed over the last 30 years, firstly on Saccharomyces cerevisiae, and, lately, with intense activity on non-Saccharomyces. Several thousand yeast strains have been isolated, identified and tested to select those with better performance and/or specific technological properties. The present review proposes a global survey of this massive ex-situ preservation of eukaryotic microorganisms, a reservoir of biotechnological solutions for the wine sector, overviewing relevant screenings that led to the selection of strains from 12 genera and 22 species of oenological significance. In the first part, the attention goes to the selection programmes related to relevant wine-producing areas (i.e. Douro, Extremadura, Galicia, La Mancha and Uclés, Ribera del Duero, Rioja, Sherry area, and Valencia). In the second part, the focus shifted on specific non-Saccharomyces genera/species selected from different Spanish and Portuguese regions, exploited to enhance particular attributes of the wines. A fil rouge of the dissertation is the design of tailored biotechnological solutions for wines typical of given geographic areas.


Assuntos
Vitis , Vinho , Saccharomyces cerevisiae , Vinho/análise , Portugal , Fermentação , Biotecnologia
2.
Rev. esp. patol. torac ; 34(2): 105-114, 23/06/2022. ilus, tab, graf
Artigo em Espanhol | IBECS | ID: ibc-206174

RESUMO

Objetivo: Establecer un modelo de muerte encefálica y trasplante pulmonar y analizar el posible papel protector del oxigenador de membrana extracorpóreo (ECMO).Métodos: Se emplearon 20 cerdos hembras, 10 donantes y 10 receptoras. Las receptoras del Grupo A (n = 5) fueron sometidas a un trasplante unipulmonar izquierdo (Tx-UPI) sin ECMO. Las receptoras del Grupo B (n = 5) se sometieron a un Tx-UPI con ECMO venoarterial (ECMO-VA). Se recopilaron datos funcionales e histológicos en situación basal, a los 10 minutos de clampar el hilio derecho (Tiempo 1) y a las 2 horas (Tiempo 2). Se analizó la expresión proteica de marcadores de inflamación y de la ruta de hipoxia.Resultados: El modelo de muerte encefálica empleado, seguido de un tiempo de isquemia frío prolongado (20 horas) dio lugar a la aparición de un edema pulmonar severo. Tras el implante, 3 receptores del grupo A sobrevivieron hasta el Tiempo 2, falleciendo 2 por edema pulmonar masivo. Por el contrario, todos los animales del Grupo B sobrevivieron, siendo la PaO2 en ese momento de 462,72 mmHg. Hubo un incremento de la expresión de IL6, TNF, PCR, AC IX y el VEGF, así como un descenso en la expresión de IL8 y GLUT1, al usar la ECMO.Conclusiones: Se ha desarrollado un modelo porcino estandarizado y reproducible de muerte encefálica, que simula el proceso clínico de la donación pulmonar. Este modelo puede servir de plataforma para investigar posibles dianas terapéuticas. (AU)


Objective: Establish a model of brain death and lung transplantation and analyze the possible protective role of extracorporeal membrane oxygenation (ECMO).Methods: 20 female pigs were used, 10 donors and 10 recipients. Group A recipients (n = 5) underwent left-sided single- lung transplantation (LUCT-Tx) without ECMO. Group B recipients (n = 5) underwent ICU-Tx with venoarterial ECMO (VA-ECMO). Functional and histological data were collected at baseline, 10 minutes after clamping the right hilum (Time 1) and 2 hours (Time 2). Protein expression of inflammation markers and the hypoxia pathway was analyzed.Results: The brain death model used, followed by a prolonged cold ischemia time (20 hours) gave rise to the appearance of severe pulmonary edema. After implantation, 3 group A recipients survived until Time 2, with 2 dying from massive pulmonary edema. In contrast, all the animals in Group B survived, with PaO2 at that time being 462.72 mmHg. There was an increase in the expression of IL6, TNFα, CRP, AC IX and VEGF, as well as a decrease in the expression of IL8 and GLUT1, when using ECMO.Conclusions: A standardized and reproducible porcine model of brain death has been developed, which simulates the clinical process of lung donation. This model can serve as a platform to investigate possible therapeutic targets. (AU)


Assuntos
Animais , Feminino , Transplante de Pulmão/métodos , Disfunção Primária do Enxerto , Circulação Extracorpórea , Oxigenadores de Membrana , Morte Encefálica , Suínos
3.
Food Chem ; 378: 132140, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35042111

RESUMO

Impact of applying monosilicic acid to grapevines during ripening on chemical composition of Mencía red wines in an area where fungal diseases during summer are common was examined. The foliar application of monosilicic acid to grapevines led to a less oxidized wine, with lower levels of acetic acid, acetaldehyde, ethyl acetate and diacethyl; this should be considered as positive from a sensory point of view. Wines made with silicon-treated grapes also contained lower levels of gluconic acid and glycerol, which are chemical markers of wines made with botrytized grapes, as well as higher contents of total phenols, anthocyanins and tannins. Furthermore, the contents of several mid-chain alcohols were higher (p < 0.05) in wines made with grapes from silicon-treated plants.


Assuntos
Vitis , Vinho , Antocianinas/análise , Frutas/química , Fenóis/análise , Vinho/análise
4.
Nat Commun ; 12(1): 2660, 2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-33976209

RESUMO

The implementation of nano-engineered composite oxides opens up the way towards the development of a novel class of functional materials with enhanced electrochemical properties. Here we report on the realization of vertically aligned nanocomposites of lanthanum strontium manganite and doped ceria with straight applicability as functional layers in high-temperature energy conversion devices. By a detailed analysis using complementary state-of-the-art techniques, which include atom-probe tomography combined with oxygen isotopic exchange, we assess the local structural and electrochemical functionalities and we allow direct observation of local fast oxygen diffusion pathways. The resulting ordered mesostructure, which is characterized by a coherent, dense array of vertical interfaces, shows high electrochemically activity and suppressed dopant segregation. The latter is ascribed to spontaneous cationic intermixing enabling lattice stabilization, according to density functional theory calculations. This work highlights the relevance of local disorder and long-range arrangements for functional oxides nano-engineering and introduces an advanced method for the local analysis of mass transport phenomena.

5.
J Appl Microbiol ; 121(5): 1346-1356, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27511798

RESUMO

AIMS: To assess the influence of non-Saccharomyces yeasts on the pyranoanthocyanins and polymeric pigments formation after the addition of (+)-catechin and procyanidin B2 to fresh red grape must. METHODS AND RESULTS: The fermentation of red grape musts was done with non-Saccharomyces yeasts either alone or in sequential fermentations with the Saccharomyces cerevisiae species. The characterization of both pyranoanthocyanin and polymeric pigments has been carried out with liquid chromatography coupled to mass spectroscopy (HPLC-DAD-ESI/MS). Red wines were also characterized by infrared spectroscopy (FTIR), gas chromatography (GC-FID) and spectrophotometry (UV-Vis). It has been observed that fermentation with the species Schizosaccharomyces pombe led to higher concentrations of pigments of all types: anthocyanins, polymeric pigments and pyranoanthocyanins, particularly vitisin A. CONCLUSIONS: The use of non-Saccharomyces yeasts improve the formation of stable pigments in red wines thanks to the differences in the microbial metabolism from among the yeasts studied. SIGNIFICANCE AND IMPACT OF THE STUDY: Colour stability as one of the main organoleptic properties in red wines, may be improved by the controlled use of selected non-Saccharomyces yeasts during red must fermentation.


Assuntos
Fermentação , Pigmentos Biológicos/biossíntese , Proantocianidinas/biossíntese , Vinho , Leveduras/metabolismo , Antocianinas/biossíntese , Biflavonoides/metabolismo , Catequina/metabolismo , Cor , Proantocianidinas/metabolismo , Saccharomyces cerevisiae/metabolismo , Schizosaccharomyces/metabolismo , Vitis , Vinho/análise
6.
Lab Chip ; 16(15): 2900-10, 2016 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-27378399

RESUMO

A novel design of a silicon-based micro-reformer for onboard hydrogen generation from ethanol is presented in this work. The micro-reactor is fully fabricated with mainstream MEMS technology and consists of an active low-thermal-mass structure suspended by an insulating membrane. The suspended structure includes an embedded resistive metal heater and an array of ca. 20k vertically aligned through-silicon micro-channels per square centimetre. Each micro-channel is 500 µm in length and 50 µm in diameter allowing a unique micro-reformer configuration that presents a total surface per projected area of 16 cm(2) cm(-2) and per volume of 320 cm(2) cm(-3). The walls of the micro-channels become the active surface of the micro-reformer when coated with a homogenous thin film of Rh-Pd/CeO2 catalyst. The steam reforming of ethanol under controlled temperature conditions (using the embedded heater) and using the micro-reformer as a standalone device are evaluated. Fuel conversion rates above 94% and hydrogen selectivity values of ca. 70% were obtained when using operation conditions suitable for application in micro-solid oxide fuel cells (micro-SOFCs), i.e. 750 °C and fuel flows of 0.02 mlL min(-1) (enough to feed a one watt power source).

7.
Int J Food Microbiol ; 232: 63-72, 2016 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-27261767

RESUMO

Schizosaccharomyces was initially considered as a spoilage yeast because of the production of undesirable metabolites such as acetic acid, hydrogen sulfide, or acetaldehyde, but it currently seems to be of great value in enology.o ced Nevertheless, Schizosaccharomyces can reduce all of the malic acid in must, leading to malolactic fermentation. Malolactic fermentation is a highly complicated process in enology and leads to a higher concentration of biogenic amines, so the use of Schizosaccharomyces pombe can be an excellent tool for assuring wine safety. Schizosaccharomyces also has much more potential than only reducing the malic acid content, such as increasing the level of pyruvic acid and thus the vinylphenolic pyranoanthocyanin content. Until now, few commercial strains have been available and little research on the selection of appropriate yeast strains with such potential has been conducted. In this study, selected and wild Sc. pombe strains were used along with a Saccharomyces cerevisiae strain to ferment red grape must. The results showed significant differences in several parameters including non-volatile and volatile compounds, anthocyanins, biogenic amines and sensory parameters.


Assuntos
Fermentação , Inocuidade dos Alimentos , Malatos/metabolismo , Saccharomyces cerevisiae/metabolismo , Schizosaccharomyces/metabolismo , Vinho/microbiologia , Acetaldeído/metabolismo , Ácido Acético/metabolismo , Antocianinas/metabolismo , Aminas Biogênicas/metabolismo , Ácido Pirúvico/metabolismo , Vitis/metabolismo , Compostos Orgânicos Voláteis/metabolismo , Vinho/análise
9.
Faraday Discuss ; 182: 423-35, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26212761

RESUMO

Fabrication routes for new SOEC mesoporous nanocomposite materials as electrodes are presented in this paper. NiO-CGO and SDC-SSC are described as possible new materials and their synthesis and the cell fabrication are discussed. The obtained materials are microstructurally characterised by SEM, TEM and XRD, where the mesoporous structures are observed and analysed. The obtained samples are electrochemically analysed by I-V polarisation curves and EIS analysis, showing a maximum current density of 330 mA cm(-2) at 1.7 V. A degradation of the cell performance is evidenced after a potentiostatic test at 1.4 V after more than 40 hours. Oxygen electrode delaminating is detected, which is most probably the main cause of ageing. Even taking into account the lack of durability of the fabricated cells, the mesoporous electrodes do not seem to be altered, opening the possibility for further studies devoted to this high stability material for SOEC electrodes.

10.
Faraday Discuss ; 182: 241-55, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26204959

RESUMO

The use of cermets as fuel electrodes for solid oxide electrolysis cells requires permanent circulation of reducing gas, e.g. H2 or CO, so called safe gas, in order to avoid oxidation of the metallic phase. Replacing metallic based electrodes by pure oxides is therefore proposed as an advantage for the industrial application of solid oxide electrolyzers. In this work, full-ceramic symmetrical solid oxide electrolysis cells have been investigated for steam/CO2 co-electrolysis. Electrolyte supported cells with La(0.75)Sr(0.25)Cr(0.5)Mn(0.5)O3-δ reversible electrodes have been fabricated and tested in co-electrolysis mode using different fuel compositions, from pure H2O to pure CO2, at temperatures between 850-900 °C. Electrochemical impedance spectroscopy and galvanostatic measurements have been carried out for the mechanistic understanding of the symmetrical cell performance. The content of H2 and CO in the product gas has been measured by in-line gas micro-chromatography. The effect of employing H2 as a safe gas has also been investigated. Maximum density currents of 750 mA cm(-2) and 620 mA cm(-2) have been applied at 1.7 V for pure H2O and for H2O : CO2 ratios of 1 : 1, respectively. Remarkable results were obtained for hydrogen-free fuel compositions, which confirmed the interest of using ceramic oxides as a fuel electrode candidate to reduce or completely avoid the use of safe gas in operation minimizing the contribution of the reverse water shift reaction (RWSR) in the process. H2 : CO ratios close to two were obtained for hydrogen-free tests fulfilling the basic requirements for synthetic fuel production. An important increase in the operation voltage was detected under continuous operation leading to a dramatic failure by delaminating of the oxygen electrode.

13.
Nanotechnology ; 26(19): 195302, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25902702

RESUMO

Silicon nanowires present outstanding properties for electronics, energy, and environmental monitoring applications. However, their integration into microelectromechanical systems (MEMS) is a major issue so far due to low compatibility with mainstream technology, which complicates patterning and controlled morphology. This work addresses the growth of 〈111〉 aligned silicon nanowire arrays fully integrated into standard MEMS processing by means of the chemical vapor deposition-vapor liquid solid method (CVD-VLS) using silane as a precursor. A reinterpretation of the galvanic displacement method is presented for selectively depositing gold nanoparticles of controlled size and shape. Moreover, a comprehensive analysis of the effects of synthesis temperature and pressure on the growth rate and alignment of nanowires is presented for the most common silicon precursor, i.e., silane. Compared with previously reported protocols, the redefined galvanic displacement together with a silane-based CVD-VLS growth methodology provides a more standard and low-temperature (<650 °C) synthesis scheme and a compatible route to reliably grow Si nanowires in MEMS for advanced applications.

14.
Int Angiol ; 32(5): 512-7, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23903311

RESUMO

AIM: In epidemiological studies, peripheral arterial disease is assessed by the measurement of the ankle/brachial index (ABI), thus enabling detection of asymptomatic disease. Our aim was to evaluate the diagnostic accuracy of a validated questionnaire on intermittent claudication for peripheral arterial disease in a clinical setting. METHODS: We administered the Edinburgh questionnaire on intermittent claudication and measured ABI using a portable Doppler in 456 outpatients with type 2 diabetes. Subjects with intermittent claudication and an ABI above 0.9 were examined with color Doppler ultrasound imaging. Peripheral arterial disease was considered to be present when the ABI was <0.9 or the color Doppler arterial waveform was monophasic. RESULTS: Thirty-five (7.6%) of the 456 patients had intermittent claudication. Of these, 22 (63%) had an ABI <0.9 and the remaining 13 (37%) had an ABI >0.9. Of these latter, 12 were reexamined and 3 (25%) were found to have monophasic waveforms in color Doppler, thus being diagnosed with peripheral arterial disease. The overall accuracy of intermittent claudication for peripheral arterial disease was 75% (95% CI, 71-79). CONCLUSION: Among patients with type 2 diabetes, a normal ABI does not rule out peripheral arterial disease; the use of an intermittent claudication questionnaire is able to identify correctly the disease in 3 out of 4 patients with diabetes. Our results suggest incorporating the intermittent claudication questionnaire into the general consultation instead of the general screening of the ABI.


Assuntos
Diabetes Mellitus Tipo 2/epidemiologia , Claudicação Intermitente/diagnóstico , Doença Arterial Periférica/diagnóstico , Inquéritos e Questionários , Idoso , Índice Tornozelo-Braço , Distribuição de Qui-Quadrado , Feminino , Humanos , Claudicação Intermitente/epidemiologia , Claudicação Intermitente/fisiopatologia , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/epidemiologia , Doença Arterial Periférica/fisiopatologia , Valor Preditivo dos Testes , Prevalência , Espanha/epidemiologia , Ultrassonografia Doppler em Cores
17.
Food Chem ; 139(1-4): 1044-51, 2013 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-23561208

RESUMO

Ageing on lees involves ageing the wine in contact with yeast cells after fermentation. If combined with the addition of oak chips, it can soften the wood flavour and increase the aromatic complexity of wine. The aim of the present work is to optimise both ageing techniques through selection of an adequate Saccharomyces cerevisiae strain. The study lasted 6 months and content of polysaccharides, anthocyanins, proanthocyanidins, volatile compounds, colour parameters and sensory analysis, were periodically evaluated. Among the strains tested, G37 showed the highest release of polysaccharides (24.4±5.5 mg l(-1)). Vanillin, syringaldehyde and furfuryl alcohol increased with ageing time in 7VA2 treatment. The wine aged with CTPL14 strain presented fewer monomeric and oligomeric proanthocyanidins (12.4±0.6 and 83.4±8.3 mg l(-1), respectively), and showed the lowest astringency and bitterness sensations. Results show an improvement in the sensory profile of the red wine aged with a combination of these two techniques.


Assuntos
Manipulação de Alimentos/métodos , Saccharomyces cerevisiae/metabolismo , Vinho/análise , Antocianinas/análise , Antocianinas/metabolismo , Fermentação , Humanos , Controle de Qualidade , Quercus/química , Paladar , Vinho/microbiologia , Madeira/química
18.
Enzyme Microb Technol ; 52(2): 99-104, 2013 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-23273278

RESUMO

Hydroxycinnamate decarboxylase (HCDC) activity has been evaluated in several commercial yeast strains. The combined effect of using cinnamyl esterases (CE) and HCDC+ Saccharomyces cerevisiae strains has been studied in the formation of vinylphenolic pyranoanthocyanins (VPAs) during fermentation, analysing the kind and concentration of pigments formed according to the yeast strain used. Wines fermented with yeasts HCDC+ were contaminated with Dekkera bruxellensis and afterwards analysed to evaluate the formation of ethylphenols (EPs). The musts treated with CE and later fermented with HCDC+ yeast strains showed lower contents of 4-ethylphenol than those fermented with HCDC- strains. This reduction in the EP content is due to the transformation of hydroxycinnamic acids in stable VPAs pigments. The associated use of CEs and HCDC+ Saccharomyces strains is a natural strategy to reduce the formation of EPs in wines contaminated by Dekkera/Brettanomyces.


Assuntos
Carboxiliases/metabolismo , Hidrolases de Éster Carboxílico/metabolismo , Fenóis/metabolismo , Saccharomyces cerevisiae/enzimologia , Vinho/microbiologia , Antocianinas/análise , Brettanomyces/metabolismo , Cor , Ácidos Cumáricos/metabolismo , Dekkera/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Propionatos , Vinho/análise
19.
Int J Food Microbiol ; 159(1): 47-53, 2012 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-22921967

RESUMO

Schizosaccharomyces pombe is a non-Saccharomyces yeast strain that can ferment grape musts with high sugar contents - but it also has other metabolic and physiological properties that render it of great interest to wine biotechnologists. This work compares the production of pyranoanthocyanins by S. pombe, Saccharomyces cerevisiae and Saccharomyces uvarum during fermentation. Total pyranoanthocyanins ranged from 11.9 to 19.4 mg/l depending on the strain of S. pombe used. On average, S. pombe produced more pyruvic acid than did either Saccharomyces species; as a consequence it also formed more vitisin A-type pigments. S. pombe 938 produced the largest quantity of vitisin A (11.03±0.82 mg/l). The formation of large amounts of pyranoanthocyanins intensifies the post-fermentation colour of wines somewhat, a phenomenon that helps them maintain their colour over ageing as the natural grape anthocyanins become degraded. Some of the S. pombe strains showed hydroxycinnamate decarboxylase activity, which favours the formation of vinylphenolic pyranoanthocyanins. Fermentation with S. pombe therefore provides an interesting way of increasing the overall pyranoanthocyanin content of red wines, and of stabilising their colour during ageing.


Assuntos
Antocianinas/biossíntese , Saccharomyces cerevisiae/metabolismo , Schizosaccharomyces/metabolismo , Vitis/microbiologia , Antocianinas/metabolismo , Cor , Fermentação , Ácido Pirúvico/metabolismo , Saccharomyces/metabolismo , Vitis/metabolismo , Vinho
20.
Angiología ; 63(3): 113-118, mayo-jun. 2011.
Artigo em Espanhol | IBECS | ID: ibc-101293

RESUMO

La claudicación intermitente es la manifestación más frecuente de la enfermedad arterial periférica. Además de la limitación en la calidad de vida del paciente, es en sí misma un factor de riesgo independiente y elevado de mortalidad de origen cardiovascular. El tratamiento global empieza por un adecuado control de los factores de riesgo vascular y hábitos de vida del paciente. Debemos asociar además fármacos para reducir la aparición de complicaciones isquémicas periféricas o de otros sectores arteriales, entre los que contamos antiagregantes, estatinas y antihipertensivos. El tratamiento específico de la propia claudicación incluye programas de ejercicio físico supervisado y un tratamiento farmacológico donde debemos optar en primer lugar por los fármacos de mayor evidencia actual –cilostazol y naftidrofurilo- considerando la pentoxifilina sólo como segunda alternativa(AU)


Intermittent claudication is the most common symptom of peripheral arterial disease. Besides the limitation in the quality of life of the patient, it represents an independent risk factor and high cardiovascular mortality. The overall treatment strategy begins with an adequate control of vascular risk factors and lifestyle habits of the patient. We also associate drugs to reduce the occurrence of ischemic complications or other peripheral arterial sectors, essentially, antiplatelet agents, statins and antihypertensives. The specific treatment for claudication includes supervised exercise programs and drug treatment. We must first choose from the drugs with most updated evidence, cilostazol and naftidrofuryl, considering pentoxifylline only as the second alternative(AU)


Assuntos
Humanos , Claudicação Intermitente/tratamento farmacológico , Inibidores da Agregação Plaquetária/uso terapêutico , Fatores de Risco , Prostaglandinas/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Nafronil/uso terapêutico , Pentoxifilina/uso terapêutico
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