10 research outputs found
Enzimska ekstrakcija hidroksicinamiÄnih kiselina iz otpada nastalog pri proizvodnji kave
Ferulic, caffeic, p-coumaric and chlorogenic acids are classified as hydroxycinnamic acids, presenting anticarcinogenic, anti-inflammatory and antioxidant properties. In this work, enzymatic extraction has been studied in order to extract high value-added products like hydroxycinnamic acids from coffee pulp. A commercial pectinase and enzyme extract produced by Rhizomucor pusillus strain 23aIV in solid-state fermentation using olive oil or coffee pulp (CP) as an inducer of the feruloyl esterase activity were evaluated separately and mixed. The total content (covalently linked and free) of ferulic, caffeic, p-coumaric and chlorogenic acids was 5276 mg per kg of coffee pulp. Distribution was as follows (in %): chlorogenic acid 58.7, caffeic acid 37.6, ferulic acid 2.1 and p-coumaric acid 1.5. Most of the hydroxycinnamic acids were covalently bound to the cell wall (in %): p-coumaric acid 97.2, caffeic acid 94.4, chlorogenic acid 76.9 and ferulic acid 73.4. The content of covalently linked hydroxycinnamic acid was used to calculate the enzyme extraction yield. The maximum carbon dioxide rate for the solid-state fermentation using olive oil as an inducer was higher and it was reached in a short cultivation time. Nevertheless, the feruloyl esterase (FAE) activity (units per mg of protein) obtained in the fermentation using CP as an inducer was 31.8 % higher in comparison with that obtained in the fermentation using olive oil as the inducer. To our knowledge, this is the first report indicating the composition of both esterified and free ferulic, caffeic, p-coumaric and chlorogenic acids in coffee pulp. The highest yield of extraction of hydroxycinnamic acids was obtained by mixing the produced enzyme extract using coffee pulp as an inducer and a commercial pectinase. Extraction yields were as follows (in %): chlorogenic acid 54.4, ferulic acid 19.8, p-coumaric acid 7.2 and caffeic acid 2.3. An important increase in the added value of coffee pulp was mainly due to the extraction of chlorogenic acid.Ferulinska, kafeinska, p-kumarinska i klorogena kiselina pripadaju u hidroksicinamiÄne kiseline, koje imaju antikarcinogena, protuupalna i antioksidativna svojstva. U radu je ispitana enzimska ekstrakcija hidroksicinamiÄnih kiselina iz otpada nastalog pri proizvodnji kave. Upotrijebljene su, zasebno i u smjesi, komercijalna pektinaza te enzimski esktrakt dobiven fermentacijom na Ävrstoj podlozi od maslinovog ulja ili otpada nastalog pri proizvodnji kave (da bi se potaknula aktivnost feruloil esteraze), s pomoÄu Rhizomucor pusillus 23aIV. Ukupni je udio kovalentno vezanih i slobodnih hidroksicinamiÄnih kiselina bio 5276 mg/kg otpada. Od toga je bilo: 58,7 % klorogene; 37,6 % kafeinske; 2,1 % ferulinske i 1,5 % p-kumarinske kiseline. VeÄina je hidroksicinamiÄnih kiselina bila kovalentno vezana za staniÄnu stijenku, i to: 97,2 % p-kumarinske; 94,4 % kafeinske; 76,9 % klorogene i 73,4 % ferulinske kiseline. PomoÄu udjela kovalentno vezanih hidroksicinamiÄnih kiselina izraÄunat je prinos ekstrahiranog enzima. Maksimalni je udio fermentacijom proizvedenog CO2 postignut na Ävrstoj podlozi od maslinovog ulja, i to za kraÄe vrijeme nego na podlozi od otpada nastalog pri proizvodnje kave, iako je feruloil esteraza proizvedena primjenom ove druge podloge pokazala aktivnost veÄu za 31,8 %. Prema spoznajama autora ovo je prvo istraĆŸivanje u kojem su odreÄeni udjeli vezanih i slobodnih hidroksicinamiÄnih kiselina u otpadu nastalom pri proizvodnji kave. NajveÄi je prinos ekstrakcije hidroksicinamiÄnih kiselina postignut primjenom komercijalne pektinaze i enzimskog ekstrakta. Pritom je izdvojeno 54,4 % klorogene; 19,8 % ferulinske; 7,2 % p-kumarinske i 2,3 % kafeinske kiseline, pa je zakljuÄeno da je ovaj postupak dobar za ekstrakciju klorogene kiseline
Dynamically Configurable Nonlinear Optical Switching Based on Vertically Aligned Carbon Nanotubes
Enzymatic Extraction of Hydroxycinnamic Acids from Coffee Pulp
Ferulic, caffeic, p-coumaric and chlorogenic acids are classified as hydroxycinnamic acids, presenting anticarcinogenic, anti-inflammatory and antioxidant properties. In this work, enzymatic extraction has been studied in order to extract high value-added products like hydroxycinnamic acids from coffee pulp. A commercial pectinase and enzyme extract produced by Rhizomucor pusillus strain 23aIV in solid-state fermentation using olive oil or coffee pulp (CP) as an inducer of the feruloyl esterase activity were evaluated separately and mixed. The total content (covalently linked and free) of ferulic, caffeic, p-coumaric and chlorogenic acids was 5276 mg per kg of coffee pulp. Distribution was as follows (in %): chlorogenic acid 58.7, caffeic acid 37.6, ferulic acid 2.1 and p-coumaric acid 1.5. Most of the hydroxycinnamic acids were covalently bound to the cell wall (in %): p-coumaric acid 97.2, caffeic acid 94.4, chlorogenic acid 76.9 and ferulic acid 73.4. The content of covalently linked hydroxycinnamic acid was used to calculate the enzyme extraction yield. The maximum carbon dioxide rate for the solid-state fermentation using olive oil as an inducer was higher and it was reached in a short cultivation time. Nevertheless, the feruloyl esterase (FAE) activity (units per mg of protein) obtained in the fermentation using CP as an inducer was 31.8 % higher in comparison with that obtained in the fermentation using olive oil as the inducer. To our knowledge, this is the first report indicating the composition of both esterified and free ferulic, caffeic, p-coumaric and chlorogenic acids in coffee pulp. The highest yield of extraction of hydroxycinnamic acids was obtained by mixing the produced enzyme extract using coffee pulp as an inducer and a commercial pectinase. Extraction yields were as follows (in %): chlorogenic acid 54.4, ferulic acid 19.8, p-coumaric acid 7.2 and caffeic acid 2.3. An important increase in the added value of coffee pulp was mainly due to the extraction of chlorogenic acid
Corrosion Behavior of Al Modified with Zn in Chloride Solution
Aluminum-based alloys have been considered candidate materials for cathodic protection anodes. However, the Al-based alloys can form a layer of alumina, which is a drawback in a sacrificial anode. The anodes must exhibit uniform corrosion to achieve better performance. Aluminum can be alloyed with Zn to improve their performance. In this sense, in the present research, the electrochemical corrosion performance of Al-xZn alloys (x = 1.5, 3.5, and 5 at.% Zn) exposed to 3.5 wt.% NaCl for 24 h was evaluated. Polarization curves, linear polarization resistance (LPR), and electrochemical impedance spectroscopy (EIS) were used to identify the electrochemical behavior. The microstructure of the samples before the corrosion assessment was characterized by means of X-ray diffraction analyses (XRD) and scanning electron microscopy (SEM). In addition, microstructures of the corroded surfaces were characterized using X-ray mappings via SEM. Polarization curves indicated that Zn additions changed the pseudo-passivation behavior from what pure Al exhibited in a uniform dissolution regime. Furthermore, the addition of Zn shifted the corrosion potential to the active side and increased the corrosion rate. This behavior was consistent with the proportional decrease in polarization resistance (Rp) and charge transfer resistance (Rct) in the EIS. The analysis of EIS was done using a mathematical model related to an adsorption electrochemical mechanism. The adsorption of chloride at the Al-Zn alloy surface formed aluminum chloride intermediates, which controlled the rate of the process. The rate constants of the reactions of a proposed chemical mechanism were evaluated
Revolution: Museo de las estrellas un paseo por la fama : Hollywood
Convocatoria proyectos de innovaciĂłn de Extremadura 2020/2021Se describe un proyecto llevado a cabo entre 13 centros educativos extremeños que consistiĂł en desarrollar cinco unidades de trabajo gamificadas, cinco historias detectivescas con misterios por resolver, donde se ponĂan a prueba las habilidades de lĂłgica, la capacidad de observaciĂłn, de concentraciĂłn y de atenciĂłn de los alumnos. Los objetivos principales de la propuesta fueron: promover la puesta en prĂĄctica de proyectos intercentros; impulsar pedagogĂas activas; desarrollar la competencia digital a travĂ©s del uso de las pedagogĂas emergentes lo que ha permitido llevar a cabo una enseñanza presencial, hĂbrida y virtual y atender a la diversidadExtremaduraES
Association of General and Abdominal Obesity With Hypertension, Dyslipidemia and Prediabetes in the PREDAPS Study
AsociaciĂłn de obesidad general y abdominal con hipertensiĂłn, dislipemia y presencia de prediabetes en el estudio PREDAPS
The risk of COVID-19 death is much greater and age dependent with type I IFN autoantibodies
International audienceSignificance There is growing evidence that preexisting autoantibodies neutralizing type I interferons (IFNs) are strong determinants of life-threatening COVID-19 pneumonia. It is important to estimate their quantitative impact on COVID-19 mortality upon SARS-CoV-2 infection, by age and sex, as both the prevalence of these autoantibodies and the risk of COVID-19 death increase with age and are higher in men. Using an unvaccinated sample of 1,261 deceased patients and 34,159 individuals from the general population, we found that autoantibodies against type I IFNs strongly increased the SARS-CoV-2 infection fatality rate at all ages, in both men and women. Autoantibodies against type I IFNs are strong and common predictors of life-threatening COVID-19. Testing for these autoantibodies should be considered in the general population
The risk of COVID-19 death is much greater and age dependent with type I IFN autoantibodies
International audienceSignificance There is growing evidence that preexisting autoantibodies neutralizing type I interferons (IFNs) are strong determinants of life-threatening COVID-19 pneumonia. It is important to estimate their quantitative impact on COVID-19 mortality upon SARS-CoV-2 infection, by age and sex, as both the prevalence of these autoantibodies and the risk of COVID-19 death increase with age and are higher in men. Using an unvaccinated sample of 1,261 deceased patients and 34,159 individuals from the general population, we found that autoantibodies against type I IFNs strongly increased the SARS-CoV-2 infection fatality rate at all ages, in both men and women. Autoantibodies against type I IFNs are strong and common predictors of life-threatening COVID-19. Testing for these autoantibodies should be considered in the general population