Liquid–liquid equilibrium of the Ucon 50-HB5100/sodium citrate aqueous two-phase systems

The phase diagrams of Ucon 50-HB5100/sodium citrate aqueous two-phase systems were determined at 5, 20 and 40 ◦C. Two medium pHs 5.20 and 8.20 were assayed. The binodal curves were satisfactorily described using a four-parameter sigmoidal equation. The two-phase area was expanded by increasing both pH and temperature. The reliability of the measured tie line compositions was ascertained by correlation equations given by Othmer–Tobias and Bancroft.VALNATURACONICETALFA II-0440-FA-Exchange programme between Universities of the European Union and Latin Americ

Liquid-liquid equilibrium and partitioning features of bovine trypsin in Ucon 50 HB5100 /sodium citrate aqueous two phase systems

The phase diagrams of Ucon 50-HB-5100, a non-ionic random copolymer of ethylene oxide and propylene oxide (EOPO) and sodium citrate aqueous two-phase systems were determined at different pHs (5.20 and 8.20) and temperatures (5, 20 and 40º C). The binodal curves were determined by refractive index and enzymatic assay of the solution and described using a four-parameter sigmoidal equation, the reliability of the measured tie line compositions was ascertained by correlation equations given by Othmer Tobias and Bancroft. The two-phase area was expanded by increasing both pH and temperature. The partitioning of bovine trypsin and a-chymotrypsin, proteases of similar physico-chemical properties was investigated in order to evaluate the applicability of partitioning as a putative method to isolate from pancreas and to obtain any information about their partitioning mechanism. The effect of different factors such as pH, tie line length and the presence of an inorganic salt on the protein partition coefficient were analyzed.Se caracterizaron las curvas binomiales correspondientes a los sistemas bifásicos acuosos formados por Ucon 50-HB-5100, un copolímero al azar de óxido de etileno y óxido de propileno (EOPO) y citrato de sodio a diferentes pHs (5,20 y 8,20) y temperaturas (5, 20 y 40º C). Las curvas binomiales se obtuvieron por determinación del índice de refracción y ensayos enzimáticos de las soluciones correspondientes; las composiciones de las líneas de unión se corroboraron por las ecuaciones propuestas por Othmer Tobias y Bancroft. El aumento del pH y la temperatura condujeron a un aumento del área bifásica. También se ensayó el comportamiento de reparto de dos proteasas tripsina y α-quimotripsina con el objetivo de emplear los principios de partición como método de aislamiento y purificación de Tripsina a partir de páncreas bovino y de obtener información acerca del mecanismo de partición de la misma. Se analizó el efecto del pH, longitud de la línea de unión y presencia de sales inorgánicas sobre el coeficiente de partición de las enzimas

Biological extraction of bromelain from pineapple byproducts

[Excerpt] Isolation and purification of valuable compounds are very important processes to valorize agro-food byproducts. Currently, protein extraction and development of environmentally friendly technologies are industrially relevant topics [1]. Among the extracted proteins from byproducts proteases are a relevant group for industrial applications. These enzymes are a class of hydrolytic enzymes capable of cleaving the peptide bonds of proteins chains and are essential in physiological processes [2]. (...

Adsorption of peroxidase from Raphanus sativus L onto alginateguar gum matrix: Kinetic, equilibrium and thermodynamic analysis

This work explores the kinetics, equilibrium and thermodynamics of peroxidase adsorption onto spherical guar gumalginate matrices. The effect of contact time, solution pH, initial protein concentration and temperature was studied in batch experiments. The results show that peroxidase adsorption increased with rising contact time and initial enzyme concentration, and was higher at pH 4.0. The kinetic processes can be predicted by both the pseudo-first-order rate kinetics and the pseudo-second-order rate kinetics. Equilibrium adsorption data were analyzed with different isotherm models. The experimental data fitted to the Freundlich model in agreement with the low energy activation, demonstrating the presence of a high physical and unspecific interaction between the enzyme and the matrix.The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: FonCyT, Projects PICT 2013–271 – Argentina Innovator 2020 and Biotechnologies to Valorize the regional food Biodiversity in Latin America – Marie Curie Actions – IRSES Project number 611493 – European Community.info:eu-repo/semantics/publishedVersio

Production of a xylanase by Trichoderma harzianum (Hypocrea lixii) in solid-state fermentation and its recovery by an aqueous two-phase system

Production of xylanase enzyme by fungi strains has gained interest in the recent years due to its high productivity, high catalytic power, as well as its potential applications in different areas such as feed, food, textile, and biofuel industries. The conventional methodologies, to produce enzymes, involve complex apparatus and chemical solvents and are associated with high costs and low- yield recovery. To obtain the high-yield recovery of the enzymes, modern enzyme extraction methods are taken into account. Aqueous two-phase systems (ATPS) are an alternative separative methodology for the purification and recovery of the enzymes and other biomolecules. The advantages of ATPS are easy scale-up and extraction, volume reduction, and rapid separation. The objective of this study was to produce Trichoderma harzianum xylanase by solid-state fermentation (SSF) using corn cobs as a support/substrate and employing ATPS for its partial recovery. In this study, the results showed the ability of a microorganism to grow on the corn cobs and to produce the xylanase enzyme. Xylanolytic activity reached 7.85 U/g of corn cobs. The enzyme was efficiently concentrated by ATPS. In addition, a high purification factor (10-fold) and considerable enzyme recovery (%ER) (84%) percentage were obtained

Optimization of bromelain isolation from pineapple byproducts by polysaccharide complex formation

Supplementary data related to this article can be found at https:// doi.org/10.1016/j.foodhyd.2018.09.009.A simple method for bromelain extraction from industrial pineapple residues (stems and peels) was developed and optimized through factorial experimental design. The developed methodology, based on precipitation with carrageenan, represents an alternative to the use of organic solvents and inorganic salts (common industrial precipitation) and allows achieving extracts with high bromelain purity. High recovery yield 8090% - of active bromelain was obtained for both crude juices (stems and peels) making possible to obtain ca. 0.3g of bromelain from 100g of pineapple byproducts using a low polysaccharide concentration (0.20.3% w/v).This work was financially supported by BiValBi - Biotechnologies to Valorise the regional Biodiversity in Latin America, in the funding project FP7-PEOPLE-2013-IRSES PEOPLE Marie Curie Programthrough project reference PIRSES-GA-2013-611493. We would like to thank the scientific collaboration of CBQF under the FCT – Fundação para a Ciência e a Tecnologia through project Multibiorefinery – Multi-purpose strategies for the valorization of a wide range of agroforestry byproducts and fisheries: A step forward in the creation of an integrated biorefinery, (POCI-01-0145-FEDER-0066), project UID/Multi/50016/ 2013 and by PhD grant SFRH/BD/104074/2014 to Débora Campos.info:eu-repo/semantics/publishedVersio

The Variant rs1867277 in FOXE1 Gene Confers Thyroid Cancer Susceptibility through the Recruitment of USF1/USF2 Transcription Factors

In order to identify genetic factors related to thyroid cancer susceptibility, we adopted a candidate gene approach. We studied tag- and putative functional SNPs in genes involved in thyroid cell differentiation and proliferation, and in genes found to be differentially expressed in thyroid carcinoma. A total of 768 SNPs in 97 genes were genotyped in a Spanish series of 615 cases and 525 controls, the former comprising the largest collection of patients with this pathology from a single population studied to date. SNPs in an LD block spanning the entire FOXE1 gene showed the strongest evidence of association with papillary thyroid carcinoma susceptibility. This association was validated in a second stage of the study that included an independent Italian series of 482 patients and 532 controls. The strongest association results were observed for rs1867277 (OR[per-allele] = 1.49; 95%CI = 1.30–1.70; P = 5.9×10−9). Functional assays of rs1867277 (NM_004473.3:c.−283G>A) within the FOXE1 5′ UTR suggested that this variant affects FOXE1 transcription. DNA-binding assays demonstrated that, exclusively, the sequence containing the A allele recruited the USF1/USF2 transcription factors, while both alleles formed a complex in which DREAM/CREB/αCREM participated. Transfection studies showed an allele-dependent transcriptional regulation of FOXE1. We propose a FOXE1 regulation model dependent on the rs1867277 genotype, indicating that this SNP is a causal variant in thyroid cancer susceptibility. Our results constitute the first functional explanation for an association identified by a GWAS and thereby elucidate a mechanism of thyroid cancer susceptibility. They also attest to the efficacy of candidate gene approaches in the GWAS era

Characterization of liquid-liquid equilibria of aqueous two-phase systems containing a termosensible polymer (UCON) and sodium citrate

CONICETALFA Valnatura - Programme European Commissio

Xylanase production by solid-state fermentation and study of separation with flexible polymers chains

Xylanase is a key biocatalyst for several modern bioprocesses. It is required in large amounts and regularly it requires to be induced with xylan. Corn cob can be considered as an important source of xylan, for this reason the use of such agroindustrial residue can be an attractive alternative if it is used as support and nutrient source for fungal growth and xylanase production. One important aspect in the production of enzymes with industrial interest, refers to the process of recovery. Although the accumulation of extracellular enzymes during the solid-state fermentation facilitates their recovery, most of the methodologies used for time-consuming purification plus they are expensive and low yields. Aqueous two-phase systems (ATPS) are an attractive bioseparative technique for purification and ideal for the recovery of enzymes and other biomolecules due to the low interfacial tension and high water content, which provides a favorable environment for the preservation of the biological activity of labile molecules. In this study, it was possible to produce xylanase, allow us to obtain enzymatic activities at 2300 U L−1 and these results show us the ability of the microorganism to degrade and invade the substrate for growth. Enzyme was efficiently concentrated by ATPSFil: Gómez García, Ricardo. Universidad de Coahuila; MéxicoFil: Medina, Miguel A.. Universidad de Coahuila; MéxicoFil: Farruggia, Beatriz Monica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Procesos Biotecnológicos y Químicos Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Procesos Biotecnológicos y Químicos Rosario; ArgentinaFil: Picó, Guillermo Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Procesos Biotecnológicos y Químicos Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Procesos Biotecnológicos y Químicos Rosario; ArgentinaFil: Aguilar, Cristobal N.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Procesos Biotecnológicos y Químicos Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Procesos Biotecnológicos y Químicos Rosario; Argentina. Universidad de Coahuila; Méxic

Continuous method to determine the trypsin inhibitor activity in soybean flour

The determination of trypsin inhibitor (TI) activity is of importance to evaluate the nutritional value of soybean flours. An analytical method, which involves a continuous spectrophotometric rate determination for trypsin activity against the substrate N-benzoyl-DL-arginine p-nitroanilide, is proposed as an alternative to the standard discontinuous assay. Stopping the reaction with acetic acid and a centrifugation/filtration step to decrease turbidity are not required, thus reducing costs and sample preparation time. The TI activity of different flour samples, determined by both assays, demonstrated to be statistically comparable, irrespective of the TI concentration level. The coefficients of variation of the novel method did not exceed 8% at any concentration level. The curves of progress reaction showed a non-linear behavior in samples without TI. A reduction of incubation time from 10min to 2min increased the method sensitivity and extended its linear range. A more economical, faster and simpler assay was developed.info:eu-repo/semantics/publishedVersio