129 research outputs found

    Valorization of Tomato Processing by-Products: Fatty Acid Extraction and Production of Bio-Based Materials

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    A method consisting of the alkaline hydrolysis of tomato pomace by-products has been optimized to obtain a mixture of unsaturated and polyhydroxylated fatty acids as well as a non-hydrolysable secondary residue. Reaction rates and the activation energy of the hydrolysis were calculated to reduce costs associated with chemicals and energy consumption. Lipid and non-hydrolysable fractions were chemically (infrared (IR) spectroscopy, gas chromatography/mass spectrometry (GC-MS)) and thermally (differential scanning calorimetry (DSC), thermogravimetric analysis (TGA)) characterized. In addition, the fatty acid mixture was used to produce cutin-based polyesters. Freestanding films were prepared by non-catalyzed melt-polycondensation and characterized by Attenuated Total Reflected-Fourier Transform Infrared (ATR-FTIR) spectroscopy, solid-state nuclear magnetic resonance (NMR), DSC, TGA, Water Contact Angles (WCA), and tensile tests. These bio-based polymers were hydrophobic, insoluble, infusible, and thermally stable, their physical properties being tunable by controlling the presence of unsaturated fatty acids and oxygen in the reaction. The participation of an oxidative crosslinking side reaction is proposed to be responsible for such modifications.Andalusian Regional Government P11-TEP-7418Spanish Ministerio de Economía y Competitividad AGL2015-65246-R and AGL2017-83036-RFondo Europeo de Desarrollo Regional (FEDER) AGL2015-65246-R and AGL2017-83036-

    Chemical-physical characterization of isolated plant cuticles subjected to low-dose γ-irradiation

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    Isolated tomato fruit cuticles were subjected to low dose (80 Gy) γ-irradiation, as a potential methodology to prevent harvested fruit and vegetables spoilage. Both irradiated and non-irradiated samples have been morphologically and chemically characterized by scanning electron (SEM), atomic force (AFM), attenuated total reflectance Fourier transform infrared (ATR-FTIR) and X-ray photoelectron (XPS) spectroscopies. Additionally, electrochemical measurements comprising membrane potential and diffusive permeability were carried out to detect modifications in transport properties of the cuticle as the fruit primary protective membrane. It has been found that low dose γ-irradiation causes some textural changes on the surface but no significant chemical modification. Texture modification is found to be due to a partial removal of outermost (epicuticular) waxes which is accompanied by mild changes of electrochemical parameters such as the membrane fixed charge, cation transport number and salt permeability. The modification of such parameters indicates a slight reduction of the barrier properties of the cuticle upon low dose γ-irradiation.

    Evaluación de tres herbicidas en el control pre emergente de arvenses en caña de azúcar (Original)

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    During the period february-june 2017, a trial was established in plots of commercial areas, in shoot stock, applied before the outbreak of the foliage on a Fluvisol soil (Alluvial). The experiment was carried out in a random block design, with 4 treatments and 4 replications, the area of ​​the plot of 0.009 ha (90 m2) per treatment in the Agricultural Production Cooperative (CPA) "Omar Rivero Fonseca", of the Base Business Unit (UEB) Bartolomé Masó, located in the town of Vuelta del Caño, municipality of Manzanillo, Granma province, with the objective of evaluating the effect of three herbicides on the variety of sugarcane CP 52-43, suckers. The herbicides evaluated were the Mayoral LS 35 at 0,600 L / ha p.c applied in pre-emergence before germination irrigation; Herbicide MerlinGD 75 at 0.270 kg / ha p.c; In addition, the total Merlin 60 SC was used at 0.250 L / ha p.c and finally a Control A (absolute) was used where the effectiveness of each herbicide treated in the cover of weeds could be compared. The product was applied with Matabi backpack hand sprayer five days after the cut (5 DDC), under dry soil conditions, where the results were obtained at the beginning of 2018.Durante el período febrero-junio 2017, se estableció un ensayo en parcelas de áreas comerciales, en cepa de retoño, aplicadas antes del brote del follaje sobre un Fluvisol. El experimento se realizó en un diseño de bloque al azar, con cuatro tratamientos y cuatro réplicas, el área de la parcela de 0,009 ha (90m2) por tratamento en la Cooperativa de Producción Agropecuaria (CPA) “Omar Rivero Fonseca”, de la Unidad Empresarial de Base (UEB) Bartolomé Masó, ubicada en el poblado Vuelta del Caño, municipio de Manzanillo, provincia Granma, con el objetivo de evaluar el efecto de tres herbicidas en la variedad de caña de azúcar CP 52-43, retoños. Los herbicidas evaluados fueron El Mayoral LS 35a 0,600 L/ha p. c aplicado en preemergencia antes del riego de germinación; el herbicida Merlin GD 75 a 0.270 kg/ha p.c; además se utilizó el Merlin total 60 SC a 0.250 L/ha p.c y por último se utilizó un Testigo A (absoluto) donde se pudiera comparar la eficacia de cada herbicida tratado en la cobertura de arvenses. El producto se aplicó con asperjadora manual Mochila Matabia los cincodías después del corte (5 DDC), en condiciones de suelo seco, donde se obtuvieron los resultados a principios del año 2018

    Le secteur caprin laitier andalou : Stratégies de recherche, développement et formation afin d’augmenter la valeur ajoutée des fromages artisanaux

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    Résumé. Le secteur caprin laitier andalou produit 50% du lait de l’Espagne et possède des opportunités de développement très claires utilisant des races autochtones et des grandes surfaces de pâturages disponibles. La production de fromages de chèvre en Andalousie peut être considérée comme un modèle de développement rural durable. Différents organismes publics et privés ont créé récemment un réseau de travail multidisciplinaire pour travailler sur la promotion et le développement des fromages artisanaux andalous, en établissant des stratégies de recherche, de développement et de formation destinées à la valorisation de ces fromages, spécialement ceux de chèvre. A partir des résultats d’une analyse stratégique, le présent travail propose des activités de recherche, de développement et de formation consacrées à la caractérisation de la qualité des fromages artisanaux, aux études de marché sur la connaissance et la perception de la qualité, aux activités de formation spécialisée dans la fromagerie et aux activités de promotion.Abstract. The Andalusian dairy goat sector (representing 50% of the national goat milk production) has potential opportunities for development using autochthonous breeds and semi-extensive production systems. Goat cheese production in Andalusia can be considered as a model for a sustainable rural development. Public institutions of research, development, and training as well as private ones have recently created a multidisciplinary and multinstitutional network to perform actions in favour of the marketing and promotion of the andalusian goat cheeses. In this paper, through the results of a strategic analysis, some research, development, and training actions were proposed. These actions are related with the improvement of quality, and the definition of the hand made cheese attributes; studies on the demand side, and consumer perception of quality; and those related to training and promotion

    Isolation and characterization of an exopolymer produced by bacillus licheniformis: in vitro antiviral activity against enveloped viruses

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    The exopolymer (EPSp) produced by the strain B. licheniformis IDN-EC was isolated and characterized using different techniques (MALDI-TOF, NMR, ATR-FTIR, TGA, DSC, SEM). The results showed that the low molecular weight EPSp contained a long polyglutamic acid and an extracellular teichoic acid polysaccharide. The latter was composed of poly(glycerol phosphate) and was substituted at the 2-position of the glycerol residues with a αGal and αGlcNH2. The αGal O-6 position was also found to be substituted by a phosphate group. The antiviral capability of this EPSp was also tested on both enveloped (herpesviruses HSV, PRV and vesicular stomatitis VSV) and non-enveloped (MVM) viruses. The EPSp was efficient at inhibiting viral entry for the herpesviruses and VSV but was not effective against non-enveloped viruses. The in vivo assay of the EPSp in mice showed no signs of toxicity which could allow for its application in the healthcare sector.Peer reviewe

    Biodegradable Polyester Films from Renewable Aleuritic Acid: Surface Modifications Induced by Melt-polycondensation in Air.

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    Good water barrier properties and biocompatibility of long-chain biopolyesters like cutin and suberin have inspired the design of synthetic mimetic materials. Most of these biopolymers are made from esterified mid-chain functionalized ω-long chain hydroxyacids. Aleuritic (9,10,16-trihydroxypalmitic) acid is such a polyhydroxylated fatty acid and is also the major constituent of natural lac resin, a relatively abundant and renewable resource. Insoluble and thermostable films have been prepared from aleuritic acid by meltcondensation polymerization in air without catalysts, an easy and attractive procedure for large scale production. Intended to be used as a protective coating, the barrier's performance is expected to be conditioned by physical and chemical modifications induced by oxygen on the air-exposed side. Hence, the chemical composition, texture, mechanical behavior, hydrophobicity, chemical resistance and biodegradation of the film surface have been studied by attenuated total reflection–Fourier transform infrared spectroscopy (ATR–FTIR), atomic force microscopy (AFM), nanoindentation and water contact angle (WCA). It has been demonstrated that the occurrence of side oxidation reactions conditions the surface physical and chemical properties of these polyhydroxyester films. Additionally, the addition of palmitic acid to reduce the presence of hydrophilic free hydroxyl groups was found to have a strong influence on these parametersEspaña Mineco CTQ2011-24299Junta de Andalucia TEP-7418. JAH-GBIOPROTO FP

    Efecto del procesado sobre las propiedades y morfología de bioplásticos de proteína de soja

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    La industria de los plásticos ha crecido notablemente en los últimos años. Este crecimiento, ligado a la baja biodegradabilidad de estos materiales, ha causado un grave problema medioambiental. La presente investigación pretende la obtención de materiales con alta capacidad de absorción de agua, que sean biodegradables y obtenidos a partir de fuentes renovables. Deberían además poseer propiedades mecánicas adecuadas para constituir una alternativa real a los plásticos sintéticos. Estos bioplásticos son obtenidos mediante un proceso con diferentes etapas: una de mezclado de los componentes para conformar una masa homogénea; y una segunda de inyección en la que, aplicando presión, la masa es introducida en un molde de forma deseada. La capacidad de absorción de agua es afectada por la composición y las condiciones de procesado. El presente documento estudia cómo la temperatura y duración de la etapa de moldeo, además del tratamiento dehidrotérmico, modifican la capacidad de absorción del bioplástico. Los resultados concluyen que la capacidad de absorción de agua aumenta con menores temperaturas y tiempos de moldeo, a la vez que aumenta cuando el tratamiento dehidrotérmico es más corto. Asimismo, los módulos viscoelásticos poseen una tendencia a disminuir cuando la capacidad de absorción de agua en las muestras aumenta.The remarkable growth experienced by the production and demand of the plastic industry during the last few years has resulted in a serious environmental issue associated specially to their low biodegradability. This work is focused on the manufacture of bioplastics with high water absorption capacity, obtained from renewable sources. Bioplastics produced should have adequate mechanical properties to be able to replace eventually synthetic plastics in specific markets. In order to obtain these bioplastics, two steps were carried out: the first one consists of a mixing stage to achieve a homogenous blend that is injection-molded during the second step. The water uptake capacity of these samples is influenced by both the formulation and the processing conditions of the blends. The present study is focused on the evolution of water uptake values when either the molding conditions (temperature and duration) or the length of a post-dehydrothermal treatment are modified. Results indicated an improvement in the water uptake when lower mold temperatures and shorter compaction stages were used. An analogous improvement was observed when the dehydrotermal process was shorter. Mechanical properties usually decreased as the water uptake of samples was improved.Plan Propio de la Universidad de Sevilla Proyecto: 2017/00000962MINECO (España)/FEDER (UE) proyecto CTQ2015-71164-

    Trajectory of post-COVID brain fog, memory loss, and concentration loss in previously hospitalized COVID-19 survivors:the LONG-COVID-EXP multicenter study

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    OBJECTIVE: This study aimed to apply Sankey plots and exponential bar plots for visualizing the trajectory of post-COVID brain fog, memory loss, and concentration loss in a cohort of previously hospitalized COVID-19 survivors.METHODS: A sample of 1,266 previously hospitalized patients due to COVID-19 during the first wave of the pandemic were assessed at 8.4 (T1), 13.2 (T2), and 18.3 (T3) months after hospital discharge. They were asked about the presence of the following self-reported cognitive symptoms: brain fog (defined as self-perception of sluggish or fuzzy thinking), memory loss (defined as self-perception of unusual forgetfulness), and concentration loss (defined as self-perception of not being able to maintain attention). We asked about symptoms that individuals had not experienced previously, and they attributed them to the acute infection. Clinical and hospitalization data were collected from hospital medical records.RESULTS: The Sankey plots revealed that the prevalence of post-COVID brain fog was 8.37% (n = 106) at T1, 4.7% (n = 60) at T2, and 5.1% (n = 65) at T3, whereas the prevalence of post-COVID memory loss was 14.9% (n = 189) at T1, 11.4% (n = 145) at T2, and 12.12% (n = 154) at T3. Finally, the prevalence of post-COVID concentration loss decreased from 6.86% (n = 87) at T1, to 4.78% (n = 60) at T2, and to 2.63% (n = 33) at T3. The recovery exponential curves show a decreasing trend, indicating that these post-COVID cognitive symptoms recovered in the following years after discharge. The regression models did not reveal any medical record data associated with post-COVID brain fog, memory loss, or concentration loss in the long term.CONCLUSION: The use of Sankey plots shows a fluctuating evolution of post-COVID brain fog, memory loss, or concentration loss during the first years after the infection. In addition, exponential bar plots revealed a decrease in the prevalence of these symptoms during the first years after hospital discharge. No risk factors were identified in this cohort.</p

    Design and implementation of an observer-based soft sensor for a heat exchanger

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    The objective of this work is to describe step-by-step how to implement an observer-based soft sensor in order to estimate process variables for which a hardware sensor is not available. The design and implementation procedure is illustrated by applying it to a counter-flow double-pipe heat exchanger. The approach used to design the nonlinear observer is based on a simplified mathematical model of the process. Numerical simulations and experiments were performed in a bench-scale pilot plant in order to validate the proposed scheme
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