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Resumen El salvado de trigo se destina principalmente al consumo animal, por lo que algunos de sus componentes son subutilizados, representando oportunidades de valor agregado. Constituye las capas externas del grano y contiene hasta 18 % en peso de proteínas con mejor calidad que las de la harina. Estas proteínas no son aprovechadas debido a que la mayoría están protegidas por una matriz de polisacáridos, indigerible para el sistema gastrointestinal humano, por lo que es necesaria su extracción. Tradicionalmente, las proteínas de salvado han sido recuperadas mediante extracción alcalina y se han propuesto como ingredientes para la elaboración de productos alimenticios. Sin embargo, su uso es casi inexistente, debido a que los procesos de extracción son agresivos y no redituables. El objetivo del presente trabajo fue describir las propiedades de las proteínas del salvado de trigo, así como sus usos potenciales. Entre sus propiedades destacan la digestibilidad, el perfil de aminoácidos y la capacidad de absorción de grasa. La fracción soluble en agua de estas proteínas, por su fácil extracción, podría tener valor agregado al utilizarse en tecnologías emergentes: como fuente de péptidos bioactivos, en la producción de nanopartículas con aplicaciones industriales o como matrices para procesos de biomineralización artificial.

Abstract Wheat bran is mainly intended for animal consumption and some of its components are underutilized, representing value-added opportunities. It forms the outer layers of the grain and contains up to 18 % by weight of proteins of better quality than those of flour. These proteins are not exploited because most are protected by a matrix of polysaccharides, which is indigestible by the human gastrointestinal system" so their extraction is necessary. Traditionally, wheat bran proteins have been recovered by alkaline extraction and have been proposed as ingredients for the manufacture of foodstuffs. However, their use is almost non-existent because the extraction processes are aggressive and not profitable. The aim of the present review is to present the proper ties of wheat bran proteins, as well as, their potential uses. Among their properties, the digestibility, lipid absorption capacity and aminoàcid pattern are highlighted. The water soluble fraction of these proteins, because of their easy extraction, could have an added value from the perspetive of emerging technologies, for example, as a source of bioactive peptides, in the production of nanoparticles with industrial applications or as matrices for artificial biomineralization processes.

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Pectins are plant cell wall natural heteropolysaccharides composed mainly of α-1-4 d-galacturonic acid units, which may or may not be methyl esterified, possesses neutral sugars branching that harbor functional moieties. Physicochemical features as pH, temperature, ions concentration, and cosolute presence, affect directly the extraction yield and gelling capacity of pectins. The chemical and structural features of this polysaccharide enables its interaction with a wide range of molecules, a property that scientists profit from to form new composite matrices for target/controlled delivery of therapeutic molecules, genes or cells. Considered a prebiotic dietary fiber, pectins meetmany regulations easily, regarding health applications within the pharmaceutical industry as a raw material and as an agent for the prevention of cancer. Thus, this review lists many emergent pectin-based composite materials which will probably palliate the impact of obesity, diabetes and heart disease, aid to forestall actual epidemics, expand the ken of food additives and food products design.

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Aggregation and coalescence are major drawbacks that contribute to polydispersity in microparticles and nanoparticles fabricated from diverse biopolymers. This study presents the evaluation of a novel method for the direct, electrospray-induced fabrication of small, CaCl2/ethanol-hardened low methoxy pectin/arabinoxylans composite microbeads. The electrospray method was evaluated to control particle size by adjusting voltage, flux, and crosslinking solution content of CaCl2/ethanol. A bead diameter of 1µm was set as reference to test the capability of this method. Insulin was chosen as a model carried molecule. Statistical analysis was a central composite rotatable design (CCRD) with a factorial arrangement of 24. The variables studied were magnitude and particle size dispersion. For the determination of these variables, light diffraction techniques, scanning electron microscopy, transmission electron microscopy, and confocal laser scanning microscopy were used. Major interaction was found for ethanol and CaCl2 as well as flow and voltage. Stable spherical structures of core⁻shell beads were obtained with neither aggregation nor coalescence for all treatments where ethanol was included in the crosslinking solution, and the average diameter within 1 ± 0.024 µm for 11 KV, 75% ethanol with 11% CaCl2, and flow of 0.97 mL/h.

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The goal of this research was to determine whether there are differences between the major oxidation products formed during the reaction of quercetin unhydrate (QUH) or quercetin dihydrate (QDH) with the 2,2-diphenyl-1-picrylhydrazyl free radical (DPPH), as well as to identify some properties of these products. The study was carried out employing spectroscopic and computational methods, in order to know the effect of different conformations of quercetin on the mechanism of free radical scavenging. The results demonstrated that although the same oxidation products may be formed from QUH and QDH, their properties and the predominant product were different in each. The o-quinone was the predominant oxidation product of QUH, whereas in QDH it was established an equilibrium between o-quinone and extended p-quinone.

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Los nanotubos de carbono (NTC) son estructuras artificiales novedosas que presentan propiedades físicas inusuales. Estas propiedades han hecho a los NTC objeto de una gran cantidad de estudios, los cuales han revelado un inmenso potencial de aplicación en diferentes áreas, tales como la electrónica, la física y la biología. En este trabajo se revisan los conceptos básicos sobre la química, obtención y modificación de los NTC, y se discute su posible utilización en sistemas biológicos.

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Zucchini fruits were subjected to 2.5 or 10 degrees C for 16d, followed by transfer to 20 degrees C for 24h in order to evaluate the relationship between ripening pattern, measured as CO(2) evolution and ethylene (C(2)H(4)) production, and metabolic heat production (q). Chilling injury (CI) visible symptoms were evident after 8d at 2.5 degrees C, but none were recorded on fruits kept at 10 degrees C. In fruits held at 10 degrees C, q, C(2)H(4) production, and CO(2) evolution diminished in the course of 16d, whereas in those at 2.5 degrees C CO(2) evolution showed an early burst peaking at 8d. Both C(2)H(4) production and q also showed a burst at 2.5 degrees C but they started at 4 and 8d, respectively, and peaked at 12d. The results showed that irreversibility of chilling injury in zucchini could occur long before the appearance of visible symptoms, although the metabolic activity accompanying the irreversibility process was not noticeable by isothermal calorimetry.

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