Effects of pulsed electric field-assisted osmotic dehydration and edible coating on the recovery of anthocyanins from in vitro digested berries

Berry fruits, such as strawberries and blueberries, are rich sources of anthocyanins. Several studies have been made on the impact of non-thermal treatments on safety, shelf-life and nutritional characteristics of such products, but the effects of these processes on anthocyanin stability during digestion in the gastrointestinal tract are still not completely clear. The aim of this study was to assess the recovery of anthocyanins after simulated gastrointestinal digestion of (1) strawberry samples, pre-treated with pulsed electric field (PEF) at 100 or 200 V\ub7cm 121, prior to osmotic dehydration (OD), and (2) blueberry samples coated with chitosan and procyanidin. After digestion, a significantly higher content of cyanidin-3-O-glucoside and malvidin-3-O-glucoside was quantified by LC-MS/MS in processed strawberry and blueberry samples, compared with the controls. The highest recovery of cyanidin-3-O-glucoside was detected in digested strawberry samples osmotically dehydrated with trehalose. The recovery of malvidin-3-O-glucoside was highest in digested blueberries coated with chitosan and stored for 14 days, compared with untreated samples or samples coated with chitosan and procyanidin. Our study shows the potential of mild PEF treatments combined with OD, or the use of edible coating, to obtain shelf-stable products without substantially affecting the composition or the stability of anthocyanins during digestion in the upper gastrointestinal tract

Influence of pulsed electric field and ohmic heating pretreatments on enzyme and antioxidant activity of fruit and vegetable juices

The objective of this work was to optimize pulsed electric field (PEF) or ohmic heating (OH) application for carrot and apple mashes treatment at different preheating temperatures (40, 60 or 80 \ub0C). The effect of tissue disintegration on the properties of recovered juices was quantified, taking into account the colour change, the antioxidant activity and the enzyme activity of peroxidase (POD) in both carrot and apple juice and polyphenol oxidase (PPO) in apple juice. Lower \u394E and an increase of the antioxidant activity were obtained for juice samples treated with temperature at 80 \ub0C with or without PEF and OH pretreatment compared with those of untreated samples. The inactivation by 90% for POD and PPO was achieved when a temperature of 80 \ub0C was applied for both carrot and apple mash. A better retention of plant secondary metabolites from carrot and apple mashes could be achieved by additional PEF or OH application. Obtained results are the basis for the development of targeted processing concepts considering the release, inactivation and retention of ingredients

Lasting temperature effects on the muscle tissue, body growth and fillet texture of adult turbots, Scophthalmus maximus, L.

In the teleosts, several factors can influence the muscle growth patterns of fish by a modulation of the hypertrophy and hyperplasia. The temperature (T) is one of the most important environmental factors. Thus, the T history of fish influences on their potential growth, as it has been observed in Salmon, Salmo salar (Johnston et al., 2003) and other species. The T imprinting can influence on the muscle cellularity throughout the advanced stages of life due to the lasting T effects on myogenic cells precursors (MPC) (Steinbacher et al., 2011). In different teleost species, a correlation between texture and muscle fibre size has been demonstrated (Hatae et al., 1990). Hence, the thermal history can also influence in the flesh texture. In the present work we study the lasting T effects in adult turbots reared at different Ts during the early phases. This species reaches ≈ 1.5 kg at 18-20 months of age and the first sexual maturity takes place at ≈ 24 month

Amino acid stable N isotope estimations reveal uniform diazotrophic contributions across zooplankton size fractions in the subtropical N Atlantic

presentacionNatural abundance of stable N isotopes (d15N) in both individual amino acids and bulk organic matter of size-fractionated plankton samples were compared to analyze the differential impact of nitrogen fixation through the food web, in a transect across the subtropical North Atlantic. Low d15N values in the central and western regions were consistent with the prevalence of nitrogen fixation, while maximum d15N values tracked the influence of West African upwelling in the eastern zone. Compound-specific amino acid isotope data (CSI-AA) revealed relatively low variability in the impact of diazotrophic nitrogen within the different plankton size fractions, while d15N of bulk organic matter showed higher variability with size. Moreover, CSI-AA results also indicated a greater importance of diazotrophy than suggested by bulk d15N values. Trophic position estimates using CSI-AA showed the expected general increase with mean plankton size class and varied in a relatively narrow range (1.8 to 2.5), with the lowest values in the central zone. Using isotopic δ15N values of individual amino acids (in particular Phe and Thr), as well as reconstructed total protein d15N values, a set of new relationships with bulk plankton d15N was determined, aimed to improve the use CSI-AA data in tracing direct plankton contributions to organic nitrogen pools in the ocean. These new results represent the most detailed investigation of CSI-AA data in zooplankton size classes to date, and point to a key role of large zooplankton in the transmission of the diazotrophic nitrogen up oceanic food webs.Malaspina-2010(CSD2008-00077), NSF Grant OCE-113181

Analytical solution of a plane strain pure bending problem in second gradient electroelasticity

Semi-inverse analytical solution of a pure bending problem for piezoelectric layer is developed in the framework of linear electroelasticity theory with strain gradient and electric field gradient effects. Two-dimensional solution is derived assuming plane strain state of a layer. It is shown that obtained solution can be used for the validation of size-dependent beam and plate models in second gradient electroelasticity theory

A new silent hemoglobin variant in a black family from French West Indies Hemoglobin Le Lamentin α20 His → Gln

AbstractA new abnormal hemoglobin Hb Le Lamentin α20 (B1) His→Gln was discovered during a survey of cord blood from the French West Indies (Martinique). This variant displays an electrophoretic pattern similar to that of Hb A but can be isolated by isoelectric focusing (IEF) and Biorex 70 chromatography. Family studies showed the presence of this hemoglobin variant in the father and in two of his three children. Hematological data from the carriers were normal

Stability of circular orbits of spinning particles in Schwarzschild-like space-times

Circular orbits of spinning test particles and their stability in Schwarzschild-like backgrounds are investigated. For these space-times the equations of motion admit solutions representing circular orbits with particles spins being constant and normal to the plane of orbits. For the de Sitter background the orbits are always stable with particle velocity and momentum being co-linear along them. The world-line deviation equations for particles of the same spin-to-mass ratios are solved and the resulting deviation vectors are used to study the stability of orbits. It is shown that the orbits are stable against radial perturbations. The general criterion for stability against normal perturbations is obtained. Explicit calculations are performed in the case of the Schwarzschild space-time leading to the conclusion that the orbits are stable.Comment: eps figures, submitted to General Relativity and Gravitatio

Inhibition of brain energy metabolism by the α-keto acids accumulating in maple syrup urine disease

AbstractNeurological dysfunction is a common finding in patients with maple syrup urine disease (MSUD). However, the mechanisms underlying the neuropathology of brain damage in this disorder are poorly known. In the present study, we investigated the effect of the in vitro effect of the branched chain α-keto acids (BCKA) accumulating in MSUD on some parameters of energy metabolism in cerebral cortex of rats. [14CO2] production from [14C] acetate, glucose uptake and lactate release from glucose were evaluated by incubating cortical prisms from 30-day-old rats in Krebs–Ringer bicarbonate buffer, pH 7.4, in the absence (controls) or presence of 1–5 mM of α-ketoisocaproic acid (KIC), α-keto-β-methylvaleric acid (KMV) or α-ketoisovaleric acid (KIV). All keto acids significantly reduced 14CO2 production by around 40%, in contrast to lactate release and glucose utilization, which were significantly increased by the metabolites by around 42% in cortical prisms. Furthermore, the activity of the respiratory chain complex I–III was significantly inhibited by 60%, whereas the other activities of the electron transport chain, namely complexes II, II–III, III and IV, as well as succinate dehydrogenase were not affected by the keto acids. The results indicate that the major metabolites accumulating in MSUD compromise brain energy metabolism by blocking the respiratory chain. We presume that these findings may be of relevance to the understanding of the pathophysiology of the neurological dysfunction of MSUD patients

Alternative pathways to a sustainable future lead to contrasting biodiversity responses

Land-use change is currently the main driver of biodiversity loss. Projections of land-use change are often used to estimate potential impacts on biodiversity of future pathways of human development. However, such analyses frequently neglect that species can persist in human-modified habitats. Our aim was to estimate changes in biodiversity, considering affinities for multiple habitats, for three different land-use scenarios. Two scenarios focused on more sustainable trajectories of land-use change, based on either technological improvements (Pathway A) or societal changes (Pathway B), and the third reflected the historical or business-as-usual trends (Pathway 0). Using Portugal as a case study, we produced spatially-explicit projections of land-use change based on these pathways, and then we assessed the resulting changes in bird species richness and composition projected to occur by 2050 in each of the scenarios. By 2050, alpha and gamma diversity were projected to decrease, relative to 2010, in Pathway 0 and increase in Pathways A and B. However, different pathways favored different species groups, and presented strong regional differences. In the technological improvement pathway, loss of extensive agricultural areas led to an increase in both natural and extensive forest areas. In this pathway, forest species increase at the expense of farmland species, while in the societal change pathway the reverse occurs, as extensive agricultural areas were projected to increase. We show that while multiple positive pathways (A and B) for biodiversity can be envisioned, they will lead to differential impacts on biodiversity depending on the transformational changes in place and the regional socio-economic context. Our results suggest that considering compositional aspects of biodiversity can be critical in choosing the appropriate regional land-use policies