140 research outputs found
Recovery and reuse of ionic liquid cholinium glycinate in the treatment of brewery spent grain
Recently, the ability of the biocompatible ionic liquid cholinium glycinate (N1112OHGly) for waste vegetable delignification like brewery spent grain (BSG) has been proved. However, the technical viability should march hand in hand with economic competitiveness. Therefore, the first step must address the reuse of the ionic liquid to mitigate the high cost associated with the synthesis of this kind of neoteric solvents. Different antisolvent-based strategies have been considered, in the present research work, to produce a delignified carbohydrate rich material (CRM) and reuse the ionic liquid. It was checked that the addition of a mixture of water: acetone (1:1 v/v) was able to efficiently precipitate carbohydrates with high levels of delignification, while about 97% of the ionic liquid is recovered at a purity near 72%. The use of this strategy allowed reusing N1112OHGly for 5 cycles and FTIR and XRD spectroscopy, scan electron microscopy (SEM) and, quantitative acid hydrolysis evidenced the suitability of the proposed process for the competitive sequential BSG delignification. Liquid chromatography sheds light on the recovery percentages and purity of the ionic liquid after each use.Xunta de Galicia | Ref. ED481A-2017/320Xunta de Galicia | Ref. ED431B 2018/5
Enzymatic hydrolysis of brewer’s spent grain to obtain fermentable sugars
Lignocellulosic biomass is a feedstock with the potential to be converted into value-added bioproducts. The use of enzymatic hydrolysis allows the cleavage of lignocellulose into their monomeric units, but there are some drawbacks that make its use in industrial biocatalysis unfeasible. In the present study, we describe the hydrolysis of brewer’s spent grain (BSG) with an enzymatic cocktail produced by Aspergillus niger CECT 2700 and its comparison with commercial enzymes. In addition, it was determined whether pretreating the BSG (non-pressurized alkaline hydrolysis or treatment with cholinium glycinate ionic liquid) is necessary. Results show that both pretreatments enhanced xylose release (10.55±0.07g/L and 8.14±0.13g/L respectively), meanwhile the hydrolysis of raw BSG with the enzymatic cocktail produced solutions containing high levels of glucose (18.45±1.66g/L) and xylose (6.38±0.26g/L).Ministerio de Economía y Competitividad | Ref. CTQ2015-71436-C2-1-
Effects of Feeding of Two Potentially Probiotic Preparations from Lactic Acid Bacteria on the Performance and Faecal Microflora of Broiler Chickens
The aim of this study was to evaluate the potential of two probiotic preparations, containing live lactic acid bacteria (Lactococcus lactis CECT 539 and Lactobacillus casei CECT 4043) and their products of fermentation (organic acids and bacteriocins), as a replacement for antibiotics in stimulating health and growth of broiler chickens. The effects of the supplementation of both preparations (with proven probiotic effect in weaned piglets) and an antibiotic (avilamycin) on body weight gain (BWG), feed intake (FI), feed consumption efficiency (FCE), relative intestinal weight, and intestinal microbiota counts were studied in 1-day posthatch chickens. The experiments were conducted with medium-growth Sasso X44 chickens housed in cages and with nutritional stressed Ross 308 broiler distributed in pens. Consumption of the different diets did not affect significantly the final coliform counts in Sasso X44 chickens. However, counts of lactic acid bacteria and mesophilic microorganisms were higher in the animals receiving the two probiotic preparations (P < 0.05). In the second experiment, although no differences in BWG were observed between treatments, Ross 308 broilers receiving the probiotic Lactobacillus preparation exhibited the lowest FCE values and were considered the most efficient at converting feed into live weight
Influence of casein hydrolysates and yeast on the rheological properties of wheat dough
The influence of casein hydrolysates (CHs) and yeast on the viscoelasticity of wheat dough at 25 °C were analysed. Three wheat doughs were studied: the unyeasted dough (UYD), the unyeasted dough with CHs (UYD-C) and the yeasted dough (YD). The characteristic parameters in the linear viscoelastic range (LVER) were analysed by stress sweep at 6.3 rad/s: UYD-C dough exhibited higher values of stress (σmax) and strain (γmax) amplitudes, and softer gel network (lower complex modulus, G*) comparing with UYD dough. The oscillatory data suggest that CHs would work as (energy and time) stabilising-agents based on the greatest reticular energy (E parameter) and the lowest frequency dependence of phase angle (δ) at the low frequency range. The rotatory tests show that CHs may act as shear thinning agents in the gluten-starch network, facilitating the solid-fluid transition at the yield point (UYD-C dough). The yeasted dough (YD) exhibited a more shear sensitive structure, evidenced in the highest influence of frequency on the elastic (G′) and viscous (G″) parameters, and gel to sol transition at 0.23 rad/s was observed
Modelling the Biphasic Growth and Product Formation by Enterococcus faecium CECT 410 in Realkalized Fed-Batch Fermentations in Whey
The influence of initial pH on growth and nutrient (total sugars, nitrogen, and phosphorous) consumption by Enterococcus faecium CECT 410 was studied during batch cultures in whey. With these data, two realkalized fed-batch fermentations were developed using different feeding substrates. The shift from homolactic to mixed acid fermentation, the biphasic kinetics observed for cell growth and nitrogen consumption and the increase in the concentrations of biomass and products (lactic acid, acetic acid, ethanol, and butane-2,3-diol) were the most noteworthy observations of these cultures. Modelling the fed-batch growth of Ent. faecium with the Logistic and bi-Logistic models was not satisfactory. However, biomass production was best mathematically described with the use of a double Monod model, which was expressed in terms of biomass, product accumulation, and nitrogen utilization. Product formation was successfully modelled with a modified form of the Luedeking and Piret model developed in this study
Effects of feeding of two potentially probiotic preparations from lactic acid bacteria on the performance and faecal microflora of broiler chickens
The aim of this study was to evaluate the potential of two probiotic preparations, containing live lactic acid bacteria (Lactococcus lactis CECT 539 and Lactobacillus casei CECT 4043) and their products of fermentation (organic acids and bacteriocins), as a replacement for antibiotics in stimulating health and growth of broiler chickens. The effects of the supplementation of both preparations (with proven probiotic effect in weaned piglets) and an antibiotic (avilamycin) on body weight gain (BWG), feed intake (FI), feed consumption efficiency (FCE), relative intestinal weight, and intestinal microbiota counts were studied in 1- day posthatch chickens. The experiments were conducted with medium-growth Sasso X44 chickens housed in cages and with nutritional stressed Ross 308 broiler distributed in pens. Consumption of the different diets did not affect significantly the final coliform counts in Sasso X44 chickens. However, counts of lactic acid bacteria and mesophilic microorganisms were higher in the animals receiving the two probiotic preparations (P < 0.05). In the second experiment, although no differences in BWG were observed between treatments, Ross 308 broilers receiving the probiotic Lactobacillus preparation exhibited the lowest FCE values and were considered the most efficient at converting feed into live weight.Instituto Nacional de Investigación y Tecnología Agraria | Ref. CAL01-045-C2-
Modelling the biphasic growth and product formation by Enterococcus faecium CECT 410 in realkalized fed-batch fermentations in whey
The influence of initial pH on growth and nutrient (total sugars, nitrogen, and phosphorous) consumption by Enterococcus faecium CECT 410 was studied during batch cultures in whey. With these data, two realkalized fed-batch fermentations were developed using different feeding substrates. The shift from homolactic to mixed acid fermentation, the biphasic kinetics observed for cell growth and nitrogen consumption and the increase in the concentrations of biomass and products (lactic acid, acetic acid, ethanol, and butane-2,3-diol) were the most noteworthy observations of these cultures. Modelling the fed-batch growth of Ent. faecium with the Logistic and bi-Logistic models was not satisfactory. However, biomass production was best mathematically described with the use of a double Monod model, which was expressed in terms of biomass, product accumulation, and nitrogen utilization. Product formation was successfully modelled with a modified form of the Luedeking and Piret model developed in this study.Instituto Nacional de Investigación y Tecnología Agraria | Ref. CAL01-045-C2-2Ministerio de Educación y Ciencia | Ref. MAT2005-05393-C03-03Ministerio de Educación y Ciencia | Ref. MAT2006-11662- C03-0
Biorefinery of brewery spent grain to obtain bioproducts with high value-added in the market
The brewery industry is under economic and environmental pressure to minimize residual management costs, particularly brewery spent grain (BSG), which accounts for 80–85% (w/w) of the total by-products generated. BSG is a lignocellulosic material primarily composed of carbohydrates, proteins and lipids. Developing a biorefinery model for conversion of BSG into value-added products is a plausible idea. Previous work optimized the pretreatment of BSG with the ionic liquid [N1112OH][Gly] and further release of fermentable sugar-containing solutions by enzymatic hydrolysis, using an enzymatic cocktail obtained by solid-state fermentation of BSG
with Aspergillus brasiliensis CECT 2700 and Trichoderma reesei CECT 2414. The current work ends the biorefinery process, studying the fermentation of these culture media with two LAB strains, Lactobacillus pentosus CECT 4023
and Lactobacillus plantarum CECT 221, from which the production of organic acids, bacteriocins, and microbial biosurfactants (mBS) was obtained. In addition to the bacteriocin activity observed, a mass balance of the whole
biorefinery process quantified the production of 106.4 g lactic acid and 6.76 g mBS with L. plantarum and 116.1 g lactic acid and 4.65 g mBS with L. pentosus from 1 kg of dry BSG. Thus, BSG shows a great potential for waste valorization, playing a major role in the implementation of biomass biorefineries in circular bioeconomy.Agencia Estatal de Investigación | Ref. PID2020–115879RB-I00São Paulo Research Foundation | Ref. 2018/25511–1São Paulo Research Foundation | Ref. 2023/09256–0Conselho Nacional de Desenvolvimento Científico e Tecnológico (Brasil) | Ref. 408783/2021–4Conselho Nacional de Desenvolvimento Científico e Tecnológico (Brasil) | Ref. 312923/2020–1Xunta de Galicia | Ref. GPC-ED431B 2021/23Universidade de Vigo/CISU
Consenso nacional de expertos: definición de criterios diagnósticos, terapéuticos y de seguimiento de la enfermedad de Cushing en pacientes colombianos
Contexto: la enfermedad de Cushing es una enfermedad poco común en la población general, con una evolución clínica insidiosa, lo cual genera un reto para el diagnóstico oportuno a partir de la sospecha clínica. Al tener en cuenta el origen de la enfermedad, dado por la presencia de un tumor hipofisario secretor de la hormona adrenocorticótropa (ACTH); el tratamiento debe estar dirigido a lograr el control bioquímico y la resección de la masa tumoral. El seguimiento del paciente, orientado a vigilar el control de la enfermedad y detectar de forma temprana el desarrollo de comorbilidades, es un aspecto clave en el manejo adecuado de la enfermedad.
Objetivo: definir criterios para el diagnóstico, el tratamiento y el seguimiento de la enfermedad de Cushing en pacientes colombianos.
Metodología: se realizó un consenso tipo Delphi modificado con un grupo multidisciplinario de expertos en el manejo del paciente con enfermedad de Cushing (médicos endocrinólogos y neurocirujanos), donde la dirección del consenso fue realizada por un médico farmacólogo clínico. Los resultados fueron analizados y discutidos y, a partir de la consecución de consensos, se presenta una serie de recomendaciones en los diferentes apartados de la enfermedad de Cushing.
Resultados: se generaron recomendaciones basadas en la opinión de expertos para el abordaje del paciente con enfermedad de Cushing, incluyendo los aspectos de sospecha clínica, diagnóstico bioquímico e imagenológico, tratamiento mediante intervención quirúrgica, alternativas de tratamiento farmacológico, radiocirugía y seguimiento del paciente.
Conclusiones: en Colombia, es importante fortalecer el conocimiento médico desde la atención primaria hasta el especialista con alta experticia en temas como el correcto diagnóstico, el manejo y el seguimiento del paciente con enfermedad de Cushing para lograr la detección temprana de la enfermedad y disminuir la progresión de las comorbilidades asociadas
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