Evolution of grape polyphenol oxidase activity and phenolic content during maturation and vinification

The activity of polyphenol oxidase (PPO) and content of phenolic compounds were followed during the maturation in two varieties of wine grapes grown in south-eastern Spain and during vinification at different sulphur dioxide concentrations.Both cresolase and catecholase activities (measured at pH 7.0 and 4.5, respectively) increased throughout the studied period and the content of phenolic compounds decreased rapidly when expressed as concentration (mg gallic acid/g total fresh weight), while when expressed as total amount per berry (mg/berry) it remained constant. During wine production, the enzyme activity was highest immediately after crushing of the fresh grapes and was not detected at the end of the fermentation process. The phenolic content also decreased during vinification to a constant level depending on the S02 level used

Study of the Properties of a Biodegradable Polymer Filled with DierentWood Flour Particles

[EN] Lignocellulosic wood flour particles with three different sizes were used to reinforce Solanyl® type bioplastic in three compositions (10, 20, and 30 wt.%) and further processed by melt-extrusion and injection molding to simulate industrial conditions. The wood flour particles were morphologically and granulometric analyzed to evaluate their use as reinforcing filler. The Fuller method on wood flour particles was successfully applied and the obtained results were subsequently corroborated by the mechanical characterization. The rheological studies allowed observing how the viscosity was affected by the addition of wood flour and to recover information about the processing conditions of the biocomposites. Results suggest that all particles can be employed in extrusion processes (shear rate less than 1000 s¿1 ). However, under injection molding conditions, biocomposites with high percentages of wood flour or excessively large particles may cause an increase in defective injected-parts due to obstruction of the gate in the mold. From a processing point of view and based on the biocomposites performance, the best combination resulted in Solanyl® type biopolymer reinforced with wood flour particles loaded up to 20 wt.% of small and medium particles size. The obtained biocomposites are of interest for injected molding parts for several industrial applications.Parres, F.; Peydro, MA.; Juárez Varón, D.; Arrieta, MP.; Aldas, M. (2020). Study of the Properties of a Biodegradable Polymer Filled with DierentWood Flour Particles. Polymers. 12(12):1-24. https://doi.org/10.3390/polym12122974124121

Utilisation du limonène comme synthon agrochimique pour la synthèse et l'extraction de produits naturels

The objective of this study was to transform limonene as an agro-chemical platform for the production of a wide range of added-value compounds for pharmaceutical, cosmetic and food ingredients. This molecule was also evaluated as an alternative solvent for the extraction of several bioactive compounds compared to n-hexane. Limonene was extracted from the essential oils of orange peels through a solvent-free microwave extraction technique. Limonene was successfully transformed into products with industrial interest by catalytic oxidation using three different iron catalysts. The ability of limonene to be used as an alternative solvent was performed using two simulation tools, Hansen solubility parameters (HSPs) and the Conductor-like Screening Model for Real Solvents (COSMO-RS), and via experimentation. The results indicated that limonene could be a promising green solvent and synthon for petroleum substitution in the extraction or synthesis of bioactive compounds.L'objectif de cette étude est de montrer les potentialités du limonène comme une plateforme agrochimique pour la production d'une large gamme de composés à valeur ajoutée pour les industries pharmaceutique, cosmétique et agroalimentaire. Cette molécule a été évaluée en tant que synthon pour la synthèse de molécules bioactives et comme solvant alternatif à l'hexane pour l'extraction de composés bioactifs. Deux outils de simulation solvant--soluté ont été utilisés pour simuler et optimiser les potentialités du limonène : les paramètres de solubilité Hansen (HSP) et le modèle « Conductor-like Screening Model for Real Solvents » (COSMO-RS). Les résultats indiquent que le limonène peut être un solvant vert et un synthon prometteur pour la substitution du pétrole dans l'extraction ou la synthèse de composés bioactifs.This work was supported in part thanks to funding from the fellowship given to Edinson Yara Varón (No. TECSPR14-2-0029) from the People Programme (Marie Curie Actions) of the Seventh Framework Programme of the European Union (FP7/2007-2013) under REA grant agreement no. 600388 (TECNIOspring programme), and from the Agency for Business Competitiveness of the Government of Catalonia, ACCIÓ

Vegetable oils as alternative solvents for green oleo-extraction, purification and formulation of food and natural products

Since solvents of petroleum origin are now strictly regulated worldwide, there is a growing demand for using greener, bio-based and renewable solvents for extraction, purification and formulation of natural and food products. The ideal alternative solvents are non-volatile organic compounds (VOCs) that have high dissolving power and flash point, together with low toxicity and less environmental impact. They should be obtained from renewable resources at a reasonable price and be easy to recycle. Based on the principles of Green Chemistry and Green Engineering, vegetable oils could become an ideal alternative solvent to extract compounds for purification, enrichment, or even pollution remediation. This review presents an overview of vegetable oils as solvents enriched with various bioactive compounds from natural resources, as well as the relationship between dissolving power of non-polar and polar bioactive components with the function of fatty acids and/or lipid classes in vegetable oils, and other minor components. A focus on simulation of solvent-solute interactions and a discussion of polar paradox theory propose a mechanism explaining the phenomena of dissolving polar and non-polar bioactive components in vegetable oils as green solvents with variable polarity.Edinson Yara Varón thanks to fellowship funding (No. TECSPR14-2-0029) from the People Programme (Marie Curie Actions) of the Seventh Framework Programme of the European Union (FP7/2007-2013) under REA grant agreement No. 600388 (TECNIOspring programme), and from the Agency for Business Competitiveness of the Government of Catalonia, ACCIÓ. Ying Li would like to thank the National Natural Science Foundation of China (Grant 31701633) and the Fundamental Research Funds for the Central Universities (Grant 17817028), as well as special funds from “SanWu Talent 2014” and sixth “100-Talent” Programs

Distinguishing N-acetylneuraminic acid linkage isomers on glycopeptides by ion mobility-mass spectrometry

Differentiating the structure of isobaric glycopeptides represents a major challenge for mass spectrometry-based characterisation techniques. Here we show that the regiochemistry of the most common N-acetylneuraminic acid linkages of N-glycans can be identified in a site-specific manner from individual glycopeptides using ion mobility-mass spectrometry analysis of diagnostic fragment ions

Calculation of loss of mechanical properties (wt%) through reprocessing and presence of impurities

[EN] Recycled materials are characterized by having endured different reprocessing cycles that cause thermal degradation and by containing often a number of impurities from different sources. In this paper, is studied the calculation of which of these two factors analyzed has more weight in the fall of mechanical properties. To carry out such work has investigated an ABS recycled from alarm systems used in Textile garments sector with presence of impurities of a 4% of PE. The results show that in the case studied, for an ABS reprocessed twice with a presence of 4% of impurities, is obtained that the thermal degradation factor has a weight of 25%, meanwhile, the presence of impurities has a weight of 75% in the fall of its properties.[ES] Los materiales reciclados se caracterizan por haber soportado diferentes ciclos de reprocesados que provocan degradación térmica y por contener frecuentemente una serie de impurezas de distinta procedencia. En este trabajo se expone el cálculo de cuál de estos dos factores tiene más peso en la caída de propiedades mecánicas. Para la realización de dicho trabajo se ha investigado un ABS reciclado procedente de sistemas de alarma utilizadas en prendas del sector Textil con una presencia de impurezas del 4% de PE. Los resultados muestran que en el caso estudiado, un ABS reprocesado dos veces y con una presencia de impurezas del 4%, el factor de la degradación térmica tiene un peso de un 25%, mientras que el otro factor, la presencias de impurezas tiene un peso del 75% en la caída de propiedades.Peydro, MA.; Parres, F.; Navarro Vidal, R.; Juárez Varón, D. (2015). Cálculo de pérdida de propiedades mecánicas (%) a través de reprocesado y presencia de impurezas. 3C Tecnología. 4(2):45-53. http://hdl.handle.net/10251/65402S45534

Coherence length of an elongated condensate: a study by matter-wave interferometry

We measure the spatial correlation function of Bose-Einstein condensates in the cross-over region between phase-coherent and strongly phase-fluctuating condensates. We observe the continuous path from a gaussian-like shape to an exponential-like shape characteristic of one-dimensional phase-fluctuations. The width of the spatial correlation function as a function of the temperature shows that the condensate coherence length undergoes no sharp transition between these two regimes.Comment: 8 pages, 6 figure, submitted to EPJ