139 research outputs found

    Selection of Saccharomyces cerevisiae strains for efficient very high gravity bio-ethanol fermentation processes

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    An optimized very high gravity (VHG) glucose medium supplemented with low cost nutrient sources was used to evaluate bio-ethanol production by 11 Saccharomyces cerevisiae strains. The industrial strains PE-2 and CA1185 exhibited the best overall fermentation performance, producing an ethanol titre of 19.2% (v/v) corresponding to a batch productivity of 2.5 g l-1 h-1, while the best laboratory strain (CEN.PK 113-7D) produced 17.5% (v/v) ethanol with a productivity of 1.7 g l-1 h-1. The results presented here emphasize the biodiversity found within S. cerevisiae species and that naturally adapted strains, such as PE-2 and CA1185, are likely to play a key role in facilitating the transition from laboratory technological breakthroughs to industrialscale bio-ethanol fermentations.Fundação para a Ciência e a Tecnologia (FCT) - PTDC/BIO/66151/2006, SFRH/ BD/64776/2009, SFRH/BPD/44328/ 200

    Recombinant family 3 carbohydrate-binding module as a new additive for enhanced enzymatic saccharification of whole slurry from autohydrolyzed eucalyptus globulus wood

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    By-products resulting from lignocellulosics pretreatment affect the digestibility of resulting whole slurries, but this can be minimized by additives supplementation. In this work, a family 3 carbohydrate-binding module (CBM3), recombinantly produced from Escherichia coli, was used as additive in the enzymatic hydrolysis of the whole slurry from autohydrolyzed Eucalyptus globulus wood (EGW). At the higher dosage used (30 mg/gsolids), CBM3 led to an increase in glucose yield from 75 to 89%. A similar result was obtained for bovine serum albumin (BSA) (11% increase), which has a well-documented additive effect. CBM3 had no effect on the non-productive binding of enzymes, since it could not bind to EGW lignin, while it rapidly bound to cellulose, as shown by fluorescence microscopy. CBM3 is a valid additive for enhanced lignocellulosic saccharification and a valuable alternative to costly additives (e.g. polyethylene glycol) as it can be affordably produced from heterologous bacterium, thus contributing to more cost-efficient biomass valorization bioprocesses.This work was developed under the strategic funding of UID/BIO/04469/2013 unit, COMPETE 2020 (POCI-01-0145-FEDER-006684) and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020—Programa Operacional Regional do Norte. The research leading to the reported results has received funding from Fundação para a Ciência e a Tecnologia (FCT) through the project MultiBiorefinery (POCI-01–0145-FEDER-016403) and through grants to C. Oliveira (SFRH/BPD/110640/2015) and D. Gomes (SFRH/BD/88623/2012).info:eu-repo/semantics/publishedVersio

    Simultaneous saccharification and fermentation of hydrothermal pretreated lignocellulosic biomass: evaluation of process performance under multiple stress conditions

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    Industrial lignocellulosic bioethanol processes are exposed to different environmental stresses (such as inhibitor compounds, high temperature, and high solid loadings). In this study, a systematic approach was followed where the liquid and solid fractions were mixed to evaluate the influence of varied solid loadings, and different percentages of liquor were used as liquid fraction to determine inhibitor effect. Ethanol production by simultaneous saccharification and fermentation (SSF) of hydrothermally pretreated Eucalyptus globulus wood (EGW) was studied under combined diverse stress operating conditions (3038 °C, 6080 g of liquor from hydrothermal treatment or autohydrolysis (containing inhibitor compounds)/100 g of liquid and liquid to solid ratio between 4 and 6.4 g liquid in SSF/g unwashed pretreated EGW) using an industrial Saccharomyces cerevisiae strain supplemented with low-cost byproducts derived from agro-food industry. Evaluation of these variables revealed that the combination of temperature and higher solid loadings was the most significant variable affecting final ethanol concentration and cellulose to ethanol conversion, whereas solid and autohydrolysis liquor loadings had the most significant impact on ethanol productivity. After optimization, an ethanol concentration of 54 g/L (corresponding to 85 % of conversion and 0.51 g/Lh of productivity at 96 h) was obtained at 37 °C using 60 % of autohydrolysis liquor and 16 % solid loading (liquid to solid ratio of 6.4 g/g). The selection of a suitable strain along with nutritional supplementation enabled to produce noticeable ethanol titers in quite restrictive SSF operating conditions, which can reduce operating cost and boost the economic feasibility of lignocellulose-to-ethanol processes.The authors thank the financial support from the Strategic Project of UID/BIO/04469/2013 CEB Unit and A Romaní postdoctoral grant funded by Xunta of Galicia (Plan I2C, 2014)

    Revisión de la literatura integradora acerca de intervenciones de la enfermería volcadas hacia el incremento del autocuidado entre pacientes con insuficiencia cardiaca

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    Objective: to analyze and summarize knowledge concerning critical components of interventions that have been proposed and implemented by nurses with the aim of optimizing self-care by heart failure patients.Methods: PubMed and CINAHL were the electronic databases used to search full peer-reviewed papers, presenting descriptions of nursing interventions directed to patients or to patients and their families and designed to optimize self-care. Forty-two studies were included in the final sample (n=4,799 patients).Results: this review pointed to a variety and complexity of nursing interventions. As self-care encompasses several behaviors, interventions targeted an average of 3.6 behaviors. Educational/counselling activities were combined or not with cognitive behavioral strategies, but only about half of the studies used a theoretical background to guide interventions. Clinical assessment and management were frequently associated with self-care interventions, which varied in number of sessions (1 to 30); length of follow-up (2 weeks to 12 months) and endpoints.Conclusions: these findings may be useful to inform nurses about further research in self-care interventions in order to propose the comparison of different modalities of intervention, the use of theoretical background and the establishment of endpoints to evaluate their effectiveness.Objetivo:analisar e sintetizar o conchecimento relacionado aos componentes críticos das intervençoes que têm, sido propostas e implementadas por enfermeiros(as) com objetivo de optimizar o auto-cuidado de pacientes portadores de insuficiência cardíaca.Método:PubMed e CINAHL foram as bases de dados electrônicas utilizadas para investigar artigos revisados por pares (peer review), apresentando as descrições das intervenções dirigidas ao paciente ou ao paciente e sua familia, visando melhorar o auto-cuidado. Foram incluídos 42 estudos na amostra final (n=4799 pacientes).Resultados:esta revisão apontou variedade e complexidade das intervenções de enfermagem. Como o auto-cuidado envolve diferentes comportamentos, as intervenções visaram em média 3,6 comportamentos. As Atividades de educação e aconselhamento foram combinadas ou não com estratégias cognitivo-comportamentais, mas somente a metade dos estudos utilizaram suporte teórico para guiar as intervenções. A avaliação e o manejo clínico foram frequentemente associados às intervenções de auto-cuidado, as quais variam em número de sessões (1 a 30), duração do seguimento (2 semanas a 12 meses) e desfechos.Conclusão:estes resultados podem ser úteis para guiar os enfermeiros no que se refere à futuros estudos sobre intervenções de auto-cuidado, de maneira a propor a comparação de diferentes modalidades de intervenção, uso de suporte teórico e estabelecimento de desfechos para melhor avaliar sua eficácia.Objetivo:analizar y sintetizar el conocimiento relacionado a componentes críticos de intervenciones que han sido propuestas e implementadas por enfermeros(as) con el objetivo de optimizar el autocuidado entre pacientes con insuficiencia cardiaca.Método:PUBMED y CINAHL han sido las bases de datos electrónicas usadas para investigar artículos revisados por pares (peer review), presentando descripciones de intervenciones destinadas a perfeccionar el autocuidado dirigido al paciente o al paciente y a su familia. Se incluyeron 42 estudios en la muestra final (n=4799 pacientes).Resultados:esta revisión apuntó a una variedad y complejidad de intervenciones de enfermería. Como el autocuidado abarca varios comportamientos, las intervenciones tuvieron como blanco, en media, 3,6 comportamientos. Actividades de educación/consejería fueron combinadas o no con estrategias cognitivo-comportamentales, pero tan solo cerca de la mitad de los estudios tenían aporte teórico para guiar intervenciones. La gestión y la evaluación clínica fueron frecuentemente asociadas a intervenciones de autocuidado, las cuales oscilaron en número de sesiones (1 a 30), duración del seguimiento (2 semanas a 12 meses) y objetivos.Conclusiones:estos resultados pueden ser útiles para informar a las enfermeras acerca de nuevas investigaciones en intervenciones de autocuidado, de modo a proponer la comparación de distintas modalidades de intervención, el uso de un aporte teórico y el establecimiento de objetivos para evaluar su eficacia
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