Tristimulus weight functions to calculate musts color coordinates from 10-nm bandwidth spectral data

Color measurement of red musts is affected by errors due to the instrument architecture. The influence of bandwidth in color coordinates errors is studied and a set of weighting functions for the color coordinates calculation, from 10 nm spectral data, is proposed

Extraction of antioxidants from winemaking byproducts: effect of the solvent on phenolic composition, antioxidant and anti-cholinesterase activities, and electrochemical behaviour

Extraction solvent is a very important factor in the recovery of antioxidants from natural matrices. In this study, the effect of three solvents (ethanol, ethanol/water and water) on the phenolic composition, antioxidant and anti-cholinesterase activities and electrochemical behaviour of four winemaking byproducts (seeds, skins, stems, and pomace) was evaluated. Phenolic composition was determined by the Folin-Ciocalteu method and ultra-high-performance liquid chromatography (UHPLC), antioxidant activity by the capacity to scavenge 2,2-diphenyl-1-picrylhydrazyl and hydroxyl radicals, anti-cholinesterase activity by the Ellman's method, and electrochemical behaviour by cyclic voltammetry. Eight phenolic compounds were quantified with higher content in water/ethanol extracts (e.g., epicatechin in pomace: 17 mg/100 g vs. 7 and 6 mg/100 g in ethanol and water extracts, respectively), although there were some exceptions (e.g., gallic acid in seeds was most abundant in water extracts). Moreover, the highest total phenolic content (TPC) and antioxidant activity were found in ethanol/water extracts (between 2 and 30-fold the values of the other extracts). Overall, the most active extracts in inhibiting both acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes were ethanol/water and ethanol extracts from seeds (between 31.11 and 53.90%). The electrochemical behaviour allowed for differentiating the extracts depending on the solvent and the byproduct. Our findings indicate that winemaking byproducts represent a source of phenolic compounds with antioxidant and anti-cholinesterase activities and suggest that cyclic voltammetry is a promising technique to evaluate the phenolic extraction process from these byproducts.FCT: DL57/2016/CP1361/CT0022.info:eu-repo/semantics/publishedVersio

Preliminary study on the use of near infrared hyperspectral imaging for quantitation and localisation of total glucosinolates in freeze-dried broccoli

peer-reviewedThe use of hyperspectral imaging to (a) quantify and (b) localise total glucosinolates in florets of a single broccoli species has been examined. Two different spectral regions (vis–NIR and NIR), a number of spectral pre-treatments and different mask development strategies were studied to develop the quantitative models. These models were then applied to freeze-dried slices of broccoli to identify regions within individual florets which were rich in glucosinolates. The procedure demonstrates potential for the quantitative screening and localisation of total glucosinolates in broccoli using the 950–1650 nm wavelength range. These compounds were mainly located in the external part of florets.Universidad de SevillaJ.M. Hernández-Hierro thanks the Spanish MICINN for the Juan de la Cierva contract (JCI-2011-09201) and Universidad de Sevilla for the mobility Grant (Universidad de Sevilla Research Plan). Spanish MICINN Project AGL2011-30254-C02 and Junta de Andalucia PGC Project AGR 6331

Impact of a post-fermentative maceration with overripe seeds on the color stability of red wines

With the purpose of modulating the copigmentation equilibria of red wines, an environmentally sustainable process was performed based on post-fermentative addition of overripe seeds (OS). Simple (SW) and double (DW) addition were performed to produce different enrichment of phenolics from seeds, hence different copigmentation/polymerization ratios. The determination of the phenolic composition showed different global increases in OS-macerates wines (catechin, epicatechin, gallic acid and procyanidins B1 and B2). The double post-maceration (DW) was more effective than the simple post-maceration addition to improve the phenolic structure of wines. The application of Differential Tristimulus Colorimetry could assess the effects of this practice on the color characteristics and stability of wines. Results highlighted that both simple and double assays underwent colorimetric improvements against the control wines (CW, no seeds addition). DW led to the highest chromatic stability, showing lower lightness, higher chroma values and bluish hues than CW. This color difference was visually detectable. © 2018 Elsevier LtdMinisterio de Economía y Competitividad (MINECO). España AGL2014-58486-C2-2-

Applications of Voltammetric Analysis to Wine Products

Wine contains polyphenols that are responsible for its quality. Moreover, phenolic compounds have antioxidant properties and benefits on human health. Cyclic voltammetry (CV) was the first electrochemical method used for polyphenols characterization and determination of polyphenols content in wine products. Electrochemical behaviour of standard solutions of phenolic compounds has been investigated and evaluated the importance of the phenolic concentration and pH. The electrochemical parameters extracted from the voltammograms have been correlated with the antioxidant potential in wine products. In addition, CV allowed establishing differences in the antioxidant activity of wines with different addition of grape seeds. In winemaking by-products, different Ipa and Q500 values were found depending on the state of maturation of the grape pomace. On the other hand, the total flavonoids and phenolic acids contents were significantly correlated to the electrochemical parameters. Differences for the electrochemical parameters were found between by-products, being pomace and seeds which presented the greatest values of Q500. Simple regression analyses showed that voltammetric parameters are correlated to their values of lipid peroxidation inhibition by thiobarbituric acid reactive substances method. Our results open the possibility of CV as a promising technique to estimate the global antioxidant potential of wine products rich in phenolic compounds

Reconstructing Viral Genomes from the Environment Using Fosmid Clones: The Case of Haloviruses

Background: Metaviriomes, the viral genomes present in an environment, have been studied by direct sequencing of the viral DNA or by cloning in small insert libraries. The short reads generated by both approaches make it very difficult to assemble and annotate such flexible genomic entities. Many environmental viruses belong to unknown groups or prey on uncultured and little known cellular lineages, and hence might not be present in databases. Methodology and Principal Findings: Here we have used a different approach, the cloning of viral DNA into fosmids before sequencing, to obtain natural contigs that are close to the size of a viral genome. We have studied a relatively low diversity extreme environment: saturated NaCl brines, which simplifies the analysis and interpretation of the data. Forty-two different viral genomes were retrieved, and some of these were almost complete, and could be tentatively identified as head-tail phages (Caudovirales). Conclusions and Significance: We found a cluster of phage genomes that most likely infect Haloquadratum walsbyi, the square archaeon and major component of the community in these hypersaline habitats. The identity of the prey could be confirmed by the presence of CRISPR spacer sequences shared by the virus and one of the available strain genomes. Other viral clusters detected appeared to prey on the Nanohaloarchaea and on the bacterium Salinibacter ruber, covering most of the diversity of microbes found in this type of environment. This approach appears then as a viable alternative to describe metaviriomes in a much more detailed and reliable way than by the more common approaches based on direct sequencing. An example of transfer of a CRISPR cluster including repeats and spacers was accidentally found supporting the dynamic nature and frequent transfer of this peculiar prokaryotic mechanism of cell protection.This work was supported by projects MAGYK (BIO2008-02444), MICROGEN (Programa CONSOLIDERINGENIO 2010 CDS2009-00006), CGL2'09-12651-C02-01 from the Spanish Ministerio de Ciencia e Innovación, DIMEGEN (PROMETEO/2010/089) and ACOMP/2009/155 from the Generalitat Valenciana. FEDER funds supported this project. IG-H was supported by MAGYK from Ministerio de Ciencia e Innovación. A-BM-C was supported by CONSOLIDER-INGENIO 2010

Influence of Different Phenolic Copigments on the Color of Malvidin 3-Glucoside

[EN]The effectiveness of seven phenolic compounds (catechin, epicatechin, procyanidin B2, caffeic acid, p-coumaric acid, myricitrin, and quercitrin) as copigments of malvidin 3-glucoside, the major anthocyanin in red wines from Vitis vinifera, using a copigment/pigment molar ratio of 1:1 was assayed ) in model wine solutions under the same conditions (pH 3.6, 12% ethanol). The stability of the copigment- ° pigment complexes formed was studied during a storage period of 60 days at 25 °C. Tristimulus colorimetry was applied for color characterization of the copigmentation process, and HPLC-DAD- MS was used to monitor changes in the composition of the samples. Copigmentation has been found to occur in all cases despite the low copigment/pigment molar ratio used, although the effect was different depending on the compound. Flavan-3-ols appeared as the less effective copigments, procyanidin B2 being even worse than monomeric flavanols, whereas flavonols behaved as the best ones. These latter copigments also induced the most statistically significant bathochromic shift in ìmax. In the colorimetric analysis, it was observed that the lightness L* of the copigmented solutions increased with time, chroma C*ab decreased, and the hue hab increased. The copigments *ab ab that produced a greater increase in the hue angle were the monomeric flavan-3-ols, which therefore showed to be the least protective cofactors against browning of the anthocyanin solution during the storage. With the time of storage, the formation of new pigments was observed in the solutions containing flavanols (xanthylium structures) and hydroxycinnamic acids (pyranoanthocyanins), whic

Observational Screening Guidelines and Smartphone Accelerometer Thresholds to Establish the Intensity of Some of the Most Popular Core Stability Exercises

The lack of training load control, mainly exercise intensity, is one of the main limitations of core stability (CS) programs, which makes the training individualization and the analysis of the dose-response relationship difficult. The objectives of this study were to assess the inter-and intra-rater agreement when using new observational screening guidelines to decide if a core stability exercise represents an adequate training intensity level for a given participant. Besides, the relationship between experts' ratings based on these criteria and pelvic accelerations recorded with a smartphone accelerometer was also analyzed. Ten healthy physically active participants with a smartphone accelerometer placed on their pelvis were video-taped while performing a progression of seven variations of the front bridge, back bridge, side bridge and bird-dog exercises. Two expert and four non-expert raters watched the videos and used the observational screening guidelines to decide for each exercise variation if it represented an adequate training intensity level or not. In order to analyze the inter-and intra-rater agreement, several Kappa (κ) statistics were used. Receiver operating characteristic (ROC) curves to explore if the accelerometry allowed to establish pelvic acceleration thresholds representing the minimum level of exercise intensity for CS training. Cut-off acceleration values were calculated balancing sensitivity (Se) and 1-specifity (1-Sp) indexes (i.e., Youden index) or minimizing 1-Sp. The intra-and inter-rater analysis showed a substantial-high level of agreement with a prevalence-adjusted bias-adjusted Kappa > 0.69. The ROC curves showed that the acceleration thresholds for the bridging exercises were very similar, with global cut-off values of 0.35 m/s2 (Se = 82%; 1-Sp = 15%) when using the Youden Index and of 0.50 m/s2 when minimizing 1-Sp (Se = 31%), whilst the bird-dog exercise showed lower cut-off values (Youden Index: 0.21 m/s2, Se = 90%, 1-Sp = 16%; minimizing 1-Sp: 0.32 m/s2, Se = 40%). Overall, this study provides observational screening guidelines and smartphone accelerometer thresholds to facilitate the decision-making process when setting the intensity of some of the most popular core stability exercises in young physically active individual

CLIPPERS syndrome with atypical distribution of lesions in magnetic resonance imaging of the brain

Introducción. El síndrome CLIPPERS (chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids) es un proceso inflamatorio del sistema nervioso central cuyo rasgo distintivo son las lesiones puntiformes en el troncoencéfalo captantes en los estudios de resonancia magnética. Clínicamente, cursa con disartria, ataxia y diplopía, y suele responder a corticoides. Anatomopatológicamente, aparecen infiltrados de linfocitos T en los espacios perivasculares troncoencefálicos. Caso clínico. Mujer de 40 años con cuadro de instauración subaguda de diplopía binocular, ataxia y disartria. En la resonancia magnética cerebral presentó lesiones puntiformes hipertintensas en secuencia T2 en el tronco, cerebelo, diencéfalo y áreas córtico-subcorticales bihemisféricas, que realzaron con contraste. Se realizó un estudio etiológico para descartar un origen infeccioso, neoplásico o inflamatorio subyacente, que resultó negativo. La paciente recibió tratamiento en dos ocasiones con metilprednisolona, con descenso progresivo de la dosis, con buena respuesta. Conclusiones. La diplopía y la ataxia, como en nuestro caso, están presentes prácticamente siempre. Los hallazgos en la RM consisten en lesiones captantes puntiformes localizadas en la protuberancia con extensión hacia el cerebelo, ganglios basales y cuerpo calloso, con gradiente de captación menor conforme se alejan rostralmente hacia la corteza, y caudalmente hacia la médula. En el caso de nuestra paciente, este gradiente no se respeta, encontrándose una densidad similar de las lesiones a nivel supratentorial. El diagnóstico diferencial es amplio y justifica un estudio diagnóstico extenso, y en casos seleccionados la biopsia cerebral. El curso de la enfermedad es remitente-recurrente, y el pronóstico mejora cuanto más precoz y prolongado es el tiempo de corticoterapiaIntroduction. CLIPPERS syndrome (chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids) is an inflammatory process of the central nervous system whose distinguishing features are the enhancing punctiform lesions in the brainstem that appear in the magnetic resonance images. Clinically, it is accompanied by dysarthria, ataxia and diplopia, and usually responds to treatment with corticoids. Pathologically, T lymphocytes appear infiltrated in the perivascular spaces of the brainstem. Case report. We report the case of a 40-year-old woman with an initial subacute clinical picture of binocular diplopia, ataxia and dysarthria. The magnetic resonance brain scan revealed T2 hyperintense punctiform lesions in the stem, cerebellum, diencephalons and cortico-subcortical areas of both hemispheres, which were enhanced with contrast. An aetiological study was performed to rule out any underlying infectious, neoplastic or inflammatory origin, the results being negative. The patient was treated on two occasions with methylprednisolone, with a gradual lowering of the dosage, the response being favourable. Conclusions. Diplopia and ataxia, as in our case, are practically always present. The MR findings consist of punctiform enhancing lesions located in the pons extending towards the cerebellum, basal ganglia and corpus callosum, the enhancement gradient becoming lower as the distance increases rostrally away from the cortex, and caudally towards the spinal cord. In the case of our patient, this gradient is not respected, and the density found was similar to that of lesions at the supratentorial level. The differential diagnosis is wide-ranging and justifies an extensive diagnostic study with, in certain cases, a biopsy study of brain tissue. The disease courses in a relapsing-remitting pattern and the earlier steroid therapy is established and the more prolonged it is, the better the prognosis will b

Color and Stability of Pigments Derived from the Acetaldehyde-Mediated Condensation between Malvidin 3-O-Glucoside and (+)-Catechin

[EN] A pigment derived from the acetaldehyde-mediated condensation between (+)-catechin and malvidin 3-O-glucoside has been prepared and isolated by semipreparative HPLC, and its characteristics of color and stability have been studied and compared with that of malvidin glucoside in aqueous solutions. When the pH was increased from 2.2 to 5.5, the solution of the pigment became progressively more violet (ìmax ) 560 nm at pH 5.5), whereas similar solutions of the anthocyanin were almost colorless at pH 4.0. This behavior indicated that the anthocyanin moiety of the pigment was more protected against water attack, and thus the formation of its quinonoidal forms was favored. The color of the pigment also showed more stability with regard to bleaching by SO2 than that of malvidin glucoside. Nevertheless, the pigment was more sensitive to degradation in aqueous solution than the anthocyanin. The cleavage of the ethyl bridge that links the anthocyanin and the catechin constituted the first step in its degradation, as demonstrated by the formation of malvidin glucoside as a major product