A First Attempt into the Production of Acylglycerol Mixtures from Echium Oil

Enzymatic glycerolysis of Echium oil (Echium plantagineum) has been carried out in the presence of four commercial lipases. Different pretreatments of the reaction mixture, such as high pressure homogenization and addition of food grade monoolein as an emulsifier, were evaluated to test their influence on the glycerolysis reaction. In addition, the impact of reducing temperature and the utilization of a solvent generally recognized as safe as a flavoring agent, such as limonene, were also investigated. Conversion of ca. 60-70% of triacylglycerols and production of ca. 25-30% of monoacylglycerols (MAGs) were attained. Finally, at the best reaction conditions, the glycerolysis reaction was scaled up at pilot plant and the product mixture obtained was fractionated via molecular distillation. From this stage, two products were attained: a distillate containing 80% of MAGs and a residue containing approximately 50% of diacylglycerols and 50% of triacylglycerols. All these mixtures can be utilized as self-emulsifying vehicles for the formulation of bioactive substances and also as precursors for the production of structured bioactive lipidsThis work was supported by the Ministerio de Economía y Competitividad (INNSAOLI, project number IPT-2011-1248- 060000, subprograma INNPACTO) and the Comunidad de Madrid (ALIBIRD, project number S2013/ABI-2728

Effects of the presence of skins during alcoholic fermentation on the composition of wine volatiles

Der Einfluß des Beerenhautkontaktes während der alkoholischen Gärung auf die Zusammensetzung der WeinaromakomponentenDie Zusammensetzung der flüchtigen und nichtflüchtigen Inhaltsstoffe von Weinen, die aus einem Most der Rebsorte Cencibel unter vier verschiedenen Gärungsbedingungen gewonnen wurden, wird beschrieben. Die Vergärung durch Saccharomyces cerevisiae erfolgte mit oder ohne Beerenhäute und mit oder ohne SO2. Die mittels konventioneller Analysenmethoden und auf gaschromatographischem Wege gewonnenen Daten wurden der Faktoren- und Clusteranalyse unterzogen. Bei einigen Komponenten traten signifikante Konzentrationsunterschiede in Abhängigkeit von den Gärungsbedingungen auf

Recovery of betulinic acid from plane tree (Platanus acerifolia L.)

Betulinic acid (3β, hydroxy-lup-20(29)-en-28-oic acid) is a bioactive triterpenic acid which was identified in various botanical sources and in considerable amounts in the bark of plane tree (Platanus acerifolia L.). In this work, the recovery of betulinic acid from plane tree bark was studied using different liquid solvent based extraction methods, namely solid-liquid extraction (SLE), ultrasound assisted extraction (UAE) and pressurized liquid extraction (PLE). Furthermore, preliminary studies of the supercritical fluid extraction (SFE) of plane tree bark are also reported. The liquid solvent based extraction techniques (SLE, UAE and PLE) were carried out using ethanol and ethyl acetate, and produced a recovery of betulinic acid in the range 10-15 mg/g of bark, with concentrations around 25-35% mass. A betulinic acid enrichment in the ethanolic extracts was possible by means of a simple precipitation step adding water. The precipitate contained 42-46% mass of betulinic acid and high recovery (>95%). Increasing the extraction temperature, by means of the PLE assays, has not resulted in an improvement of betulinic acid recovery. The preliminary SFE assays produced lower recoveries of betulinic acid (0.5-8 mg/g) with respect to liquid extraction. The addition of ethanol as cosolvent produced a significant improvement of both betulinic acid recovery and concentration in the SFE extract.This work has been supported by project ALIBIRD-S2009/AGR-1469 from Comunidad Autónoma de Madrid. López-Padilla A. thanks to COLCIENCIAS (568–2012) and Medellin Mayor's Office (Sapiencia/Enlaza Mundos Program, 2013) for the Ph.D. fellowship.Peer Reviewe

Albacore (Thunnus alalunga) larval index in the Western Mediterranean Sea, 2001-2015

Larval abundance indices express standardized abundances of larval densities from ichthyoplankton surveys. For more than two decades these indices have been used to assess the trends of the spawning stock biomass of various species in the Gulf of Mexico, being incorporated into the population models applied by ICCAT. Recently, the delta-lognormal models used for the calculation of the indices have been improved to incorporate the environmental variability and have been applied in the Balearic Sea to obtain a larval index for bluefin tuna (Thunnus thynnus). Here we apply the same methodological approach to calculate a larval index of albacore (Thunnus alalunga) from surveys conducted from 2001 to 2015 in the Balearic Sea, the most relevant spawning ground of this species in the Western Mediterranean. Results show a decreasing trend on albacore larval abundances and significant lower abundances from 2013 to 2015. This larval index, standardized for gears, sampling coverage, hour, salinity, date and sea surface temperature, attempt to provide information on the dynamic of the western Mediterranean stock of albacore, for which not much information available for assessment is availableLes indices d’abondance larvaire expriment les abondances standardisées de la densité larvaire à partir de prospections d’ichthyoplancton. Pendant plus de deux décennies, ces indices ont été utilisés pour évaluer les tendances de la biomasse du stock reproducteur de diverses espèces dans le golfe du Mexique et ont été incorporés dans les modèles de population utilisés par l’ICCAT. Récemment, les modèles delta log-normal utilisés pour calculer les indices ont été améliorés afin d’incorporer la variabilité environnementale et ont été appliqués dans la mer des Baléares afin d’obtenir un indice larvaire pour le thon rouge (Thunnus thynnus). La même méthodologie a été appliquée pour calculer un indice larvaire du germon (Thunnus alalunga) à partir des prospections réalisées entre 2001 et 2015 dans la mer des Baléares, la principale zone de frai de cette espèce de la Méditerranée occidentale. Les résultats présentent une tendance décroissante de l’abondance larvaire du germon et une abondance significativement plus faible de 2013 à 2015. Cet indice larvaire, standardisé pour les engins, la couverture de l'échantillonnage, l’heure, la salinité, la date et la température à la surface de la mer, vise à fournir des informations sur la dynamique du stock de germon de la Méditerranée occidentale, au sujet duquel il existe peu d’informations pour l’évaluationLos índices de abundancia de larvas expresan abundancias estandarizadas de densidades de larvas a partir de prospecciones de ictioplancton. Durante más de dos décadas estos índices se han utilizado para evaluar las tendencias de la biomasa reproductora del stock de varias especies en el golfo de México, y se han incorporado en los modelos de población aplicados por ICCAT. Recientemente los modelos delta lognormal utilizados para calcular los índices se han mejorado para incorporar la variabilidad medioambiental y se han aplicado al mar Balear para obtener un índice de larvas para el atún rojo (Thunnus thynnus). En este caso se ha aplicado el mismo enfoque metodológico para calcular un índice larvario de atún blanco (Thunnus alalunga) a partir de prospecciones realizadas desde 2001 a 2015 en el mar Balear, la zona de reproducción más importante para esta especie en el Mediterráneo occidental. Los resultados muestran una tendencia decreciente en la abundancia de larvas de atún blanco y unas abundancias significativamente inferiores de 2013 a 2015. Con este índice de larvas, estandarizado para los artes, la cobertura de muestreo, la hora, la salinidad, la fecha y la temperatura de la superficie del mar se intenta proporcionar información sobre la dinámica del stock de atún blanco del Mediterráneo occidental, para el que no se dispone de mucha información con vistas a su evaluaciónVersión del edito

Ácidos siálicos: distribución, metabolismo y función biológica

Sialic acids are among the most important molecules in the animal kingdom and also occur in some microorganisms. They are á-ketoacids with a nine-carbon glycid backbone. They are negatively charged and they were first discovered in mammals, although it appears that they are present in most Coelomata in both protostomes (e.g. Arthropoda) and deutorostomes (e.g. Chordata or Echinodermata). The biosynthetic pathway of Neu5Ac proceeds through the following reactions: a) synthesis of ManAc-6-P, b) synthesis of ManNAc, c) synthesis of Neu5Ac, d) activation of the monomer to CMP-â-Neu5Ac, and e) transfer of Neu5Ac to the acceptor structure. In the catabolism of this compound, the neuraminidase and Nacetyl- neuraminidate-lyase activities play important roles. In animals, sialic acids are involved in cell-to-cell interactions and mediate the regulation of recognition process. In microorganisms they are present in a few taxonomically scattered bacterial and fungal species. These microorganisms establish either symbiotic or parasitic relationships with animals and use host sialic acids either as a carbonnitrogen source or to sialylate their own cell surface.Los acidos sialicos estan entre las moleculas de mayor importancia del reino animal encontrandose tambien en algunos microorganismos. Son cetoacidos con un esqueleto glucidico de nueve carbonos, estan cargados negativamente y se descubrieron en mamiferos aunque se encuentran en la mayor parte de los celomados, en protostomados (por ejemplo, artropodos), y deutorostomados (por ejemplo, cordados y equinodermos). La ruta biosintetica del Neu5Ac tiene lugar a traves de las siguientes reacciones: a) sintesis de ManAc-6-P, b) sintesis de ManNAc, c) sintesis de Neu5Ac, d) activacion del monomero to CMP-ƒÀ-Neu5Ac, y e) transferencia del Neu5Ac a un aceptor. En el catabolismo de estos compuestos las enzimas neuraminidasa y N-acetil neuraminato liasa tienen un papel importante. En animales los acidos sialicos estan involucrados en interacciones celula-celula e intervienen en la regulacion de procesos de reconocimiento celular. En microorganismos estan presentes en un numero escaso de bacterias y hongos. Estos microorganismos los utilizan para establecer relaciones simbioticas o parasitarias con animales, para utilizarlos como fuente de nitrogeno o carbono o para sialilar su propia superficie

Phytoplankton Community Structure Is Driven by Stratification in the Oligotrophic Mediterranean Sea

The phytoplankton community composition, structure, and biomass were investigated under stratified and oligotrophic conditions during summer for three consecutive years in the Mediterranean Sea. Our results reveal that the phytoplankton community structure was strongly influenced by vertical stratification. The thermocline separated two different phytoplankton communities in the two layers of the euphotic zone, characterized by different nutrient and light availability. Picoplankton dominated in terms of abundance and biomass at all the stations sampled and throughout the photic zone. However, the structure of the picoplanktonic community changed with depth, with Synechococcus and heterotrophic prokaryotes dominating in surface waters down to the base of the thermocline, and Prochlorococcus and picoeukaryotes contributing relatively more to the community in the deep chlorophyll maximum (DCM). Light and nutrient availability also influenced the communities at the DCM layer. Prochlorococcus prevailed in deeper DCM waters characterized by lower light intensities and higher picophytoplankton abundance was related to lower nutrient concentrations at the DCM. Picoeukaryotes were the major phytoplankton contributors to carbon biomass at surface (up to 80%) and at DCM (more than 40%). Besides, contrarily to the other phytoplankton groups, picoeukaryotes cell size progressively decreased with depth. Our research shows that stratification is a major factor determining the phytoplankton community structure; and underlines the role that picoeukaryotes might play in the carbon flux through the marine food web, with implications for the community metabolism and carbon fate in the ecosystem.En prens

Caby Photometry of the Hyades: Comparisons to the Field Stars

Intermediate-band photometry of the Hyades cluster on the Caby system is presented for dwarf stars ranging from spectral type A through late K. A mean hk, b-y relation is constructed using only single stars without anomalous atmospheres and compared to the field stars of the solar neighborhood. For the F dwarfs, the Hyades relation defines an approximate LOWER bound in the two-color diagram, consistent with an [Fe/H] between +0.10 and +0.15. These index-color diagrams follow the common convention of presenting stars with highest abundance at the bottom of the plot although the index values for the metal-rich stars are numerically larger. For field F dwarfs in the range [Fe/H] between +0.4 and -1.0, [Fe/H] = -5.6 delta-hk + 0.125, with no evidence for a color dependence in the slope. For the G and K dwarfs, the Hyades mean relation crosses the field star distribution in the two-color diagram, defining an approximate UPPER bound for the local disk stars. Stars found above the Hyades stars fall in at least one of three categories: [Fe/H] below -0.7, [Fe/H] above that of the Hyades, or chromospherically active. It is concluded that, contrary to the predictions of model atmospheres, the hk index for cool dwarfs at a given color hits a maximum value for stars below solar composition and, with increasing [Fe/H] above some critical value, declines. This trend is consistent, however, with the predictions from synthetic indices based upon much narrower Ca filters where the crossover is caused by the metallicity sensitivity of b-y.Comment: 13 pages, 9 eps figures, 1 tex table, 1 ascii tabl

Polymorphic appetite effects on waist circumference depend on rs3749474 CLOCK gene variant

Chronobiological aspects controlled by CLOCK genes may influence obesity incidence. Although there are studies that show an association between the expression of these genes and energy intake, waist circumference or abdominal obesity phenotypes, interactions with appetite have been insufficiently investigated in relation to chrononutrition. The objective was to identify interactions between CLOCK genetic variants involved in appetite status. A total of 442 subjects (329 women, 113 men; aged 18 to 65 years) were recruited. Anthropometric, dietary and lifestyle data were collected by trained nutritionists. Participants were classified according to their appetite feelings with a Likert scale. Multiple linear regression models were used to examine associations of the type genotype x appetite status on adiposity-related variables. p values were corrected by the Bonferroni method. A significant influence was found concerning the effects of appetite on waist circumference with respect to rs3749474 CLOCK polymorphism (p < 0.001). An additive model analysis (adjusted by age, gender, exercise and energy intake) showed that risk allele carriers, increased the waist circumference around 14 cm (β = 14.1, CI = 6.3–22.0) by each increment in the level of appetite. The effects of appetite on waist circumference may be partly modulated by the rs3749474 CLOCK polymorphism

Nanoemulsions and acidified milk gels as a strategy for improving stability and antioxidant activity of yarrow phenolic compounds after gastrointestinal digestion

peer-reviewedThe aim of this study was to improve the stability and antioxidant activity of yarrow phenolic compounds upon an in vitro simulated gastrointestinal digestion. Therefore, two types of caseins-based delivery systems, sodium caseinate stabilized nanoemulsions (NEs) and glucono delta-lactone acidified milk gels (MGs), were formulated containing an ultrasound-assisted yarrow extract (YE) at two concentrations (1 and 2.5 mg/mL). Formulations with 1 mg/mL of YE were chosen based on their higher encapsulation efficiency to perform the in vitro digestion experiments. After digestion, YE-loaded NEs only partially protected phenolic compounds from degradation; meanwhile the phenolic composition of YE including in MGs after digestion was quite similar to undigested YE. Moreover, the antioxidant activity of MGs after digestion was higher than NEs digested samples, which confirms the higher protection of YE phenolic compound by the milk gels systems. This research demonstrated the potential use of acidified MGs as carriers to improve the stability and antioxidant activity of yarrow phenolic compounds. Therefore, these matrices could be employed to develop new dairy products enriched with phenolic compounds

Why are the K dwarfs in the Pleiades so Blue?

The K dwarfs in the Pleiades fall nearly one half magnitude below a main sequence isochrone when plotted in a color-magnitude diagram utilizing V magnitude as the luminosity index and B-V as the color index. This peculiarity has been known for forty years but has gone unexplained and mostly ignored. When compared to Praesepe members, the Pleiades K dwarfs again are subluminous (or blue) in a color-magnitude diagram using B-V as the color index. However, using V-I as the color index, stars in the two clusters are coincident to M_V ~ 10; using V-K as the color index, Pleiades late K and M stars fall above the main sequence locus defined by Praesepe members. We believe that the anomalous spectral energy distributions for the Pleiades K dwarfs, as compared to older clusters, are a consequence of rapid stellar rotation and may be primarily due to spottedness. If so, the required areal filling factor for the cool component has to be very large (=> 50%). Weak-lined T Tauri stars have similar color anomalies, and we suspect this is a common feature of all very young K dwarfs (sp. type > K3). The peculiar spectral energy distribution needs to be considered in deriving accurate pre-main sequence isochrone-fitting ages for clusters like the Pleiades since the age derived will depend on the temperature index used.Comment: 41 pages, 15 figures, AASTeX5.0. Accepted 05 May 2003; Scheduled for publication in the Astronomical Journal (August 2003