43 research outputs found

    Maximization of monomeric C5 sugars from wheat bran by using mesoporous ordered silica catalysts

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    The hydrolysis process of a real fraction of arabinoxylans derived from wheat bran was studied. The influence of catalyst type and loading, reaction time and different metal cations were discussed in terms of the hydrolysis yield of arabinose and xylose oligomers as well as the formation of furfural as degradation product. A high yield of arabinoxylans into the corresponding monomeric sugars (96 and 94% from arabino- and xylo-oligosaccharides, respectively) was obtained at relatively high temperatures (180 °C) and short reaction times (15 min) with a catalyst loading of 4.8 g of RuCl3/Al-MCM-48 per g of initial carbon in hemicelluloses.CTQ2015-64892-R (MINECO/FEDER

    10th World Congress of Chemical Engineering,

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    Extraction and Hydrolysis of arabinoxylans have been studied using RuCl3 catalysts over different mesoporous silica supports. Acidity of the catalyst is a key parameter for these processes: the higher the Acidity, the higher the Yield. Ru+3 has demonstrated to be active, as it is a moderate Lewis acid. Arabinose is always faster released than xylose: Arabinose belongs to side chains and it is linked by beta-glycosidic bonds (weak). Xylose belongs to the backbone and it is linked by β -glycosidic bonds (strong).Proyecto CTQ2015-64892-R (MINECO/FEDER

    Extraction of arabinoxylans from wheat bran using hydrothermal processes assisted by heterogeneous catalysts

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    The extraction/hydrolysis process of arabinoxylans from destarched wheat bran was studied in this work using different mesoporous silica supports and the corresponding RuCl3-based catalysts. The effects of temperature, time, catalyst supports and ruthenium catalysts were investigated and discussed in terms of the arabinoxylans extraction yield and their polymerization degree. Relatively high temperatures (180 °C), short extraction times (10 min) and RuCl3 supported on Al-MCM-48 led to a high amount of extracted arabinoxylans (78%) with a low molecular weight (9 kDa). Finally, a relation between the operating conditions, the arabinoxylans extraction yield and the molecular weight was stablished based on the obtained results.CTQ2015-64892-R (MINECO/FEDER

    Optimization of the subcritical water treatment from sunflower by-product for producing protein and sugar extracts

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    Producción CientíficaThis study proposes the valorization of sunflower by-product (SbP) using subcritical water treatment. For this purpose, a response surface methodology in a 3× 3 Box–Behnken design was employed to study the effect of temperature (100– 150 °C), extraction time (5–25 min), and solvent-to-feed ratio (10–20 g bidistilled water/g SbP) on the water-soluble compounds. The highest amount of glucose (5.7-mg/g raw material) and xylose (13.5-mg/g raw material) was obtained at 150 °C and solvent-to-feed ratio of 15 after 25 min of extraction. The highest amount of protein (133.5-mg/g raw material) was obtained at 150 °C and solvent-to-feed ratio of 20 after 15 min of extraction. The selected temperature conditions did not promote the formation of final degradation products such as furfural and 5-hydroxymethylfurfural (HMF). The extracts obtained in this study showed simultaneous recovery of free monomeric sugars that could be used for bioenergy or biochemical, proteins that could be used for food and pharmaceutical industries and phenolic compounds that could be used for food and nutraceutical applications.Junta de Castilla y León and FEDER (project VA277P18) and the EU-FEDER program (CLU-2019-04)Publicación en abierto financiada por el Consorcio de Bibliotecas Universitarias de Castilla y León (BUCLE), con cargo al Programa Operativo 2014ES16RFOP009 FEDER 2014-2020 DE CASTILLA Y LEÓN, Actuación:20007-CL - Apoyo Consorcio BUCL

    From Biomass to Sugar Alcohols: Purification of Wheat Bran Hydrolysates Using Boronic Acid Carriers Followed by Hydrogenation of Sugars over Ru/H-ZSM-5

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    Wheat bran is a lignocellulosic waste of milling industry. It contains hemicelluloses, which can be valorized into arabitol and xylitol via a few-step approach. It begins with extraction and hydrolysis of hemicelluloses to produce a solution of xylose and arabinose, along with proteins and inorganic salts. This work focuses on the purification of sugars of this hydrolysate and the subsequent catalytic production of sugar alcohols. A purification process based on the recovery of sugars by anionic extraction with a boronic acid, followed by back-extraction and a further refining step with ion exchange resins is described. After this process, a high purity sugars solution (∼90%) free of inorganic elements and proteins was obtained. The feasibility of the process was also highlighted by a successful recycling of the organic phase containing the boronic acid. The hydrogenation of purified sugars was then performed over Ru/H-ZSM-5. A high yield into pentitols of ∼70% with 100% selectivity was achieved. Importantly, the catalytic hydrogenation of sugars in the hydrolysate prior to purification did not occur. We determined that proteins caused the deactivation of the catalyst, and consequently, the inhibition of the production of sugar alcohols.Ministerio de Economía, Industria y Competitividad - Fondo Europeo de Desarrollo Regional (project CTQ2015-64892-R

    Extraction of ferulic acid and feruloylated arabinoxylo-oligosaccharides from wheat bran using pressurized hot water

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    Producción CientíficaPressurized water was tested as solvent for the hydrolysis and extraction of Ferulic acid (FA) and feruloylated arabinoxylooligosaccharides (F-AXOS) from destarched wheat bran (DWB). Results were dependent on the severity factor of the process (combination of temperature and time), obtaining the maximum extraction yields at 200°C and 3.5 min. 78% of the total FA was successfully extracted, being 17% in its free form and the rest, covalent ester-bounded to arabinoxylans. Under such conditions, 80% of the arabinoxylans are extracted with a degree of FA esterification of 1.34 g FA/100 g AXOS, and an average molecular weight of 1,3·104 Da. Pressurized Microwave Assisted Extraction was also studied to evaluate potential intensification of the process using microwaves. However, no significant differences were observed with the microwave heating. Residual solid after extraction was mainly composed by lignin and cellulose (56% and 21%, respectively) showing that hot compressed water technology can be integrated in the first steps of a biorefinery for the total valorization of the wheat bran.Ministerio de Economía, Industria y Competitividad - Fondo Europeo de Desarrollo Regional (project CTQ2015-64892-R

    Bimetallic Ru:Ni/MCM-48 Catalysts for the Effective Hydrogenation of D-Glucose into Sorbitol

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    Three different bimetallic Ru:Ni catalysts supported on a mesoporous silica MCM-48 were prepared byconsecutive wet impregnations, with a total metal loading of ca. 3% (w w−1). Ru:Ni ratios spanned in therange of 0.15–1.39 (w w−1) and were compared with the corresponding monometallic Ni/MCM-48. Thecatalysts so prepared were characterized by X-Ray Diffraction, Transmission Electron Microscopy, adsorp-tion/desorption of N2, Temperature Programmed Reduction, NH3− TPD and Atomic Absorption, andtested in the liquid phase hydrogenation of d-glucose into sorbitol in the temperature range 120–140◦Cunder 2.5 MPa of H2pressure. Bimetallic catalysts with Ru:Ni ratios higher than 0.45 enhanced the cat-alytic behavior of the monometallic Ni/MCM-48 in the reaction, increasing the reaction rate and showingcomplete selectivity to sorbitol by minimizing the production of mannitol. Ru:Ni/MCM-48 (0.45) wasrecovered from the reaction media and tested for three reaction cycles, showing good stability under theselected experimental conditions.Proyecto CTQ2015-64892-R (MINECO/FEDER)

    Evaluation of two treatment strategies for the prevention of preterm birth in women identified as at risk by ultrasound (PESAPRO Trial): Study protocol for a randomized controlled trial

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    Background: Premature birth is considered one of the main problems in modern Obstetrics. It causes more than 50 % of neonatal mortality; it is responsible for a large proportion of infant morbidity and incurs very high economic costs. Cervical length, which can be accurately measured by ultrasound, has an inverse relationship with the risk of preterm birth. As a result, having an effective intervention for asymptomatic patients with short cervix could reduce the prematurity. Although recently published data demonstrates the effectiveness of vaginal progesterone and cervical pessary, these treatments have never been compared to one another. Methods/Design: The PESAPRO study is a noncommercial, multicenter, open-label, randomized clinical trial (RCT) in pregnant women with a short cervix as identified by transvaginal ultrasonography at 19 to 22 weeks of gestation. Patients are randomized (1:1) to either daily vaginal progesterone or cervical pessary until the 37th week of gestation or delivery; whichever comes first. During the trial, women visit every 4 weeks for routine questions and tests. The primary outcome is the proportion of spontaneous preterm deliveries before 34 weeks of gestation. A sample size of 254 pregnant women will be included at 29 participating hospitals in order to demonstrate noninferiority of placing a pessary versus vaginal progesterone. The first patient was randomized in August 2012, and recruitment of study subjects will continue until the end of December 2015. Discussion: This trial assesses the comparative efficacy and safety between two accepted treatments, cervical pessary versus vaginal progesterone, and it will provide evidence in order to establish clinical recommendationsThe study has been funded by two national grants from the Spanish Ministry of Health and ISCIII

    Effectiveness of an intervention for improving drug prescription in primary care patients with multimorbidity and polypharmacy:Study protocol of a cluster randomized clinical trial (Multi-PAP project)

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    This study was funded by the Fondo de Investigaciones Sanitarias ISCIII (Grant Numbers PI15/00276, PI15/00572, PI15/00996), REDISSEC (Project Numbers RD12/0001/0012, RD16/0001/0005), and the European Regional Development Fund ("A way to build Europe").Background: Multimorbidity is associated with negative effects both on people's health and on healthcare systems. A key problem linked to multimorbidity is polypharmacy, which in turn is associated with increased risk of partly preventable adverse effects, including mortality. The Ariadne principles describe a model of care based on a thorough assessment of diseases, treatments (and potential interactions), clinical status, context and preferences of patients with multimorbidity, with the aim of prioritizing and sharing realistic treatment goals that guide an individualized management. The aim of this study is to evaluate the effectiveness of a complex intervention that implements the Ariadne principles in a population of young-old patients with multimorbidity and polypharmacy. The intervention seeks to improve the appropriateness of prescribing in primary care (PC), as measured by the medication appropriateness index (MAI) score at 6 and 12months, as compared with usual care. Methods/Design: Design:pragmatic cluster randomized clinical trial. Unit of randomization: family physician (FP). Unit of analysis: patient. Scope: PC health centres in three autonomous communities: Aragon, Madrid, and Andalusia (Spain). Population: patients aged 65-74years with multimorbidity (≥3 chronic diseases) and polypharmacy (≥5 drugs prescribed in ≥3months). Sample size: n=400 (200 per study arm). Intervention: complex intervention based on the implementation of the Ariadne principles with two components: (1) FP training and (2) FP-patient interview. Outcomes: MAI score, health services use, quality of life (Euroqol 5D-5L), pharmacotherapy and adherence to treatment (Morisky-Green, Haynes-Sackett), and clinical and socio-demographic variables. Statistical analysis: primary outcome is the difference in MAI score between T0 and T1 and corresponding 95% confidence interval. Adjustment for confounding factors will be performed by multilevel analysis. All analyses will be carried out in accordance with the intention-to-treat principle. Discussion: It is essential to provide evidence concerning interventions on PC patients with polypharmacy and multimorbidity, conducted in the context of routine clinical practice, and involving young-old patients with significant potential for preventing negative health outcomes. Trial registration: Clinicaltrials.gov, NCT02866799Publisher PDFPeer reviewe

    Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

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    The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality
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