Enzymatic production of ethyl oleate ester using a lipase from Candida antarctica B

Lipases são biocatalisadores de grande importância em diferentes áreas, sendo capazes de catalisar reações em meios aquosos ou orgânicos. Além disso, estas enzimas são capazes de utilizar vários substratos sendo estáveis numa vasta gama de pH e temperatura. Lipases promovem a esterificação entre ácidos graxos e etanol produzindo ésteres oleatos. O objetivo deste trabalho é produzir o éster oleato de etila por esterificação enzimática do ácido oleico com etanol. Uma lipase de Candida antarctica tipo B foi utilizada a uma temperatura de 55 °C. A reação foi realizada utilizando o ácido oleico, sulfato de sódio anidro, lipase e etanol, na proporção de ácido oleico (0.03 mol ou 10 ml), lipase (0.1 mol ou 0.01 g), sulfato de sódio anidro (5 g) e etanol 99 % (100 ml). Diversos tempos de reação foram estudados, nomeadamente, 48, 72, 96 e 120 horas. Ressonância Magnética Nuclear (1 H e 13C) e espectros de Infravermelho confirmaram a produção do éster oleato de etila para as condições estudadas. O maior rendimento da produção do oleato de etila foi obtido no tempo de reação de 96 horas. Os ésteres oleato de etila foram reportados por possuirem aplicações interessantes em vários campos industriais, tais como, alimentos, produtos aromáticos, cosméticos, detergentes, saborizantes e produtos farmacêuticos.Lipases are biocatalysts of great importance in different areas, being able to catalyze reactions in aqueous or organic media. Furthermore, these enzymes are capable of using several substrates being stable in a wide range of pH and temperatures. Lipases promote the esterification between fatty acids and ethanol producing oleate esters. The aim of this work is to produce ethyl oleate ester by enzymatic esterification of oleic acid with ethanol. A lipase from Candida antarctica type B was used at a temperature of 55 °C. The reaction was conducted using oleic acid, sodium sulfate anhydrous, lipase and ethanol, with a ratio of oleic acid (0.03 mol or 10 ml), lipase (0.1 mol or 0.01 g), sodium sulfate anhydrous (5 g) and ethanol 99 % (100 ml). Several reaction times were studied, namely 48, 72, 96 and 120 hours. Nuclear Magnetic Resonance (1 H and 13C) and Infrared spectra confirmed the production of ethyl oleate ester for the studied conditions. The highest ethyl oleate production yield was obtained for 96 hours reaction time. Ethyl oleate esters have been reported to possess interesting applications in several industrial fields, such as food, aromatics, cosmetics, detergents, flavors and pharmaceuticals

Yacon syrup: food applications and impact on satiety in healthy volunteers.

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The institutions of archaic post-modernity and their organizational and managerial consequences: The case of Portugal

The long march of modernization of the Western societies tends to be presented as following a regular sequence: societies and institutions were pre-modern, and then they were modernized, eventually becoming post-modern. Such teleology may provide an incomplete or distorted narrative of societal evolution in many parts of the world, even in the ‘post-modern heartland’ of Western Europe, with Portugal being a case in point. The concept of archaic post-modernity has been developed by a philosopher, José Gil, to show how Portuguese institutions and organizations combine elements of pre-modernity and post-modernity. The notion of an archaic post-modernity is advanced in order to provide an alternative account of the modernization process, which enriches discussion of the varieties of capitalism. Differences in historical experiences create singularities that may be considered in the analysis of culture, management and organization

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

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

Effect of yacon syrup on blood lipid, glucose and metabolic endotoxemia in healthy subjects: a randomized, double-blind, placebo-controlled pilot trial.

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Perception of Brazilian and Portuguese students about health promotion in university environments

Objective: To compare different perceptions of Brazilian and Portuguese health students about health promotion in the university. Method: Cross-sectional, descriptive analytical study that included 669 university students in the health courses of two universities, one Brazilian and the other Portuguese. The Instrument of Assessment for Health Promotion at University was used in both institutions and the comparisons were performed with the Chi-square test and odds ratio estimation. Results: There was a predominance of students aged up to 24years (89.2%) and females (78.3%). In general, Portuguese university students have better perceptions of the physical activity, eating habits and psychosocial factors (p<0.001). Brazilian university students presented better perceptions in the domains of environmental factors and complementary and alternative therapies (p<0.001). Conclusions: The results show that Brazilian and Portuguese students have significant differences in their perception of aspects related to health promotion at university. It is concluded that the university environment is a promising field to carry out educational practices that promote health and that this context differs between countries.info:eu-repo/semantics/publishedVersio