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Additive manufacturing via direct ink writing and microwave dielectric characterisation of commercially produced low sintering temperature bismuth molybdenum oxide ceramics, have been both performed for the first time, following a powder-to-product holistic approach. We demonstrated that direct ink writing is an excellent candidate for producing dielectric substrates to be used for wireless telecommunication applications operating at microwave (MW) frequencies, with great repeatability and properties comparable to ceramics fabricated via conventional processing routes. The optimum density (relative density of ρr ≈ 93%) of the 3D printed test samples was obtained by sintering at 660 °C for 2 h, resulting in a relative permittivity er = 35.7, dielectric loss tanδ = 0.0004 and microwave quality factor Q × f = 14,928 GHz. Sintering at higher temperatures promoted a porosity increase due to mismatching grain growth mechanisms and phase decomposition, that collectively hindered the test samples’ microwave dielectric performance in terms of achievable relative permittivity (er) and dielectric loss (tanδ).

The final carbon content of austenite in equilibrium with tempered martensite can be estimated by the so-called constrained carbon equilibrium in the presence of carbide (CCEθ) model. However, the linear predictions under CCEθ deviate from both the initial and the experimentally measured carbon content. A modified approach to the CCEθ model is proposed, which predicts an increase of the carbon content in austenite with the decrease of temperature below the onset of martensitic transformation.

Ethanol can be used as a platform molecule for synthesizing valuable chemicals and fuel precursors. Direct synthesis of C5+ ketones, building blocks for lubricants and hydrocarbon fuels, from ethanol was achieved over a stable Pd-promoted ZnO-ZrO2 catalyst. The sequence of reaction steps involved in the C5+ ketone formation from ethanol was determined. The key reaction steps were found to be the in situ generation of the acetone intermediate and the cross-aldol condensation between the reaction intermediates acetaldehyde and acetone. The formation of a Pd-Zn alloy in situ was identified to be the critical factor in maintaining high yield to the C5+ ketones and the stability of the catalyst. A yield of >70 % to C5+ ketones was achieved over a 0.1 % Pd-ZnO-ZrO2 mixed oxide catalyst, and the catalyst was demonstrated to be stable beyond 2000 hours on stream without any catalyst deactivation.

Wire arc additive manufacturing (WAAM) is a class of technologies suitable for producing large parts due to its high material deposition and building rates. Among the many possible materials processed by WAAM, austenitic stainless steels, e.g. 316L, are commonly employed. The structure of WAAM 316L thin parts has been studied extensively before. However, multiwalled or thick WAAM 316L parts remain largely unexplored. Hence, in this study, the microstructure of a thick 316LSi WAAM part is characterised in detail. The microstructure of the part consists of large and highly-oriented columnar grains dominated by epitaxial and competitive growth. The overlapping regions between neighbouring fusion zones contain long grains with a dominant texture, which cross several layers and are aligned with the building direction. The grains' internal microstructure consists of an austenite matrix, ferrite with locally varying dendritic morphologies and dispersed oxide inclusions. The texture spatially varies across the part, and this variation is correlated to the local thermal gradient induced by the building strategy and processing conditions used during the manufacturing of the thick-walled part.

Lycopene is a naturally occurring chemical compound that gives fruits and vegetables a red/orange color. As an intermediate metabolite of β-carotene biosynthesis, lycopene represents one of the major carotenoids. This work studies the gene expression pattern of lycopene biosynthesis/catabolism transcripts and the accumulation pattern of lycopene/β-carotene/chlorophyll contents at three developmental stages and three tissues in five widely consumed, commercial tomato cultivars (cvs. ‘Cherry Ninolino F1’, ‘Elpida F1’, ‘Daphne F1’, ‘Eliseo Plum F1’, and ‘Oxheart’). These contents were correlated with in vitro antioxidant activity. Higher levels of lycopene were observed in the peel than other tissues and in the fully ripe stage, with ‘Oxheart’ displaying the highest content. Differential regulation of lycopene biosynthetic genes (SlZDS and SlCRTISO) was demonstrated in all cultivars. Interestingly, a gene implicated in lycopene catabolism (SlLCYB) demonstrated a general induction in the tested tissues. High lycopene content correlates with significant induction of both SlZDS and SlCRTISO in ‘Oxheart’. Significantly increased antioxidant activity was observed in the peel of ‘Cherry Ninolino F1’ and ‘Elpida F1’ cultivars compared with other tested tissues across all cultivars. The exploration of lycopene activity in different cultivars and the consumption of ripe tomatoes including the peel could be useful for the protection of human health.

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The impact of tandem dehydrogenation-aldol condensation reactions on the structure of oxide-supported PdCu catalysts was studied by a combination of X-ray tomography measurements, ensemble-averaging spectroscopy techniques and reactivity measurements. X-ray tomography measurements generated 3D images at submicron resolution of the packed catalyst in the flow reactor following its exposure to various reaction conditions. Quantitative analysis of the tomography data revealed that exposure of the catalyst to reaction conditions induced structural deformation of the mixed Mg-Al oxide supports, accompanied by sintering of the PdCu nanoparticles into micron-sized aggregates. Improved stability was achieved once the PdCu particles were supported on an oxide, such as anatase TiO2, which does not undergo restructuring or phase transition under reaction conditions. This study demonstrates that structural information extracted by X-ray tomography measurements may uncover important structure-reactivity correlations and identify the reasons for catalysts deactivation.

The kinetics of methane oxidation over Pt/Al2O3, Pd/Al2O3, and Ag–Pd/Al2O3 is investigated as a function of the O2/CH4 ratio. We show that as the oxygen fraction increases from low values, three distinct kinetic regimes exist that are nearly first order, negative order, and zero order with respect to the oxygen concentration. At O2/CH4 < 3, Pd and Ag–Pd are superior catalysts, whereas at higher oxygen concentrations, Pt is superior. Hysteresis with bistability is demonstrated over all three catalysts with two distinct activity regimes at identical feed compositions: higher activity upon increasing oxygen concentration from low values and lower activity upon decreasing oxygen concentration from high values. In situ X-ray absorption spectroscopy (XAS) and X-ray photoelectron spectroscopy (XPS) over the Ag–Pd catalyst suggest that the bistability stems from different oxidation states of the catalyst as well as a core–shell structure in the reduced state.

Carob fruit is considered as a rich source of phenolics that are linked with potent health effects. The aim of this work was to study the effect of a triple-step digestion on the stability of phenolics and antioxidant potency in carob products. Results showed that the gastric and intestinal steps induced the most significant changes in the stability of pure phenolics; their recovery ranged between 61 and 88% at oral, 40–87% at gastric and 16–57% at intestinal step. Regarding to the carob products, the yield of phenolic contents were ranged from 0.83 to 1.41 for gastric and from 0.43 to 0.82 for intestinal phase. The counterpart yield of antioxidant potency was 0.84–1.66 and 0.48–0.67, respectively. HPLC analysis also disclosed interesting findings; the stability of phenolics is strongly influenced by their chemical structure. In general, the phenolic acids are quite resistant under digestion procedure, whereas the flavonols are mostly degraded when they were subjected into digestion. Results points out that the carob phenolics are degraded, released from food matrix or attached to other food or digestive juice constituents. Furthermore, the critical role of food matrix was underlined as the food components had a protective effect against pH changes and enzymatic activities along digestion.

Fundamental knowledge of the active site requirements for the selective activation of C–O bonds over heterogeneous catalysts is required to design multistep processes for the synthesis of complex chemicals. Here we employ reaction kinetics measurements, extensive catalyst characterization, first principles calculations and microkinetic modelling to reveal metal oxides as a general class of catalysts capable of selectively cleaving C–O bonds with unsaturation at the α position, at a moderate temperature and H2 pressure. Strikingly, metal oxides are considerably more active catalysts than commonly employed VIIIB and IB transition metal catalysts. We identify the normalized Gibbs free energy of oxide formation as both a reactivity and a catalyst stability descriptor and demonstrate the generality of the radical-mediated, reverse Mars–van Krevelen C–O bond activation mechanism on oxygen vacancies, previously established only for RuO2. Importantly, we provide evidence that the substrate plays an equally key role to the catalyst in C–O bond activation. Metal oxides have been identified as a promising class of catalysts for carbon–oxygen bond cleavage in the context of biomass valorization, although the systematic understanding of their reactivity remains elusive. Now, a combination of catalytic screening and first principles calculations provide important insights into this family of catalysts.

Vitamin E is a general term used to describe a group of eight lipophilic compounds known as tocochromanols. These vitamin E variants are chemically categorised into two classes formed by α-, β-, γ- and δ- tocopherols and tocotrienols isoforms, respectively. The present study describes the concurrent regulation of genes and metabolites orchestrating vitamin E biosynthesis in olive drupes of five distinctive Greek olive cultivars. A combination of analytical, biochemical and molecular approaches was employed in order to carry out comparative analyses, including real-time RT-qPCR for gene expression levels and HPLC analysis of metabolite content. Findings indicated that tocochromanol levels and composition, oil content, gene expression levels as well as total antioxidant activity were highly dependent on cultivar and, to a lesser extent, on fruit developmental stage. Specifically, cultivars 'Kalokairida' and 'Lianolia Kerkyras' demonstrated the highest vitamin E content. The latter possessed high tocochromanol content combined with highest overall antioxidant activity in all developmental stages, concomitant with the up-regulation expression profile of HPPD. The genotypic imprint versus the temporal contribution to vitamin E levels, as well as the potential link to lipid peroxidation amelioration, are discussed.

Wine and by-products are essential elements of a Mediterranean diet and considered as a reservoir of bioactive compounds with various health effects. Grape pomace, an easily available natural material of low cost, shares a similar wealth of health benefiting bioactive phytochemicals. The objective of this study was to explore the utilization of grape pomace from Commandaria dessert wine as main ingredient for functional infusions. Therefore, the ratio of water to grape pomace powder (40–200 mL g−1), infusion time (3–15 min) and temperature (55–95 °C) were optimized in terms of composition and bioactivity. Multiple response optimization indicated that brewing 200 mL water per g of material for 12.2 min at 95 °C, was the optimum method for preparing the infusion. Results also revealed a significant impact of three parameters as well as quadratic and interactive effects on composition and bioactivity of infusions. Furthermore, the infusion presents antimicrobial effects against Listeria monocytogenes serotypes and other common food pathogenic bacteria. Finally, a sensory evaluation was performed to assess the organoleptic attributes of the infusion and its improvement, with the addition of Mediterranean aromatic plants. Overall, the present work describes a promising strategy for the re-use of sun-dried grape pomace as a functional ingredient of infusions.

One of the prevailing perceptions regarding the ageing of cells and organisms is the intracellular gradual accumulation of oxidatively damaged macromolecules, leading to the decline of cell and organ function (free radical theory of ageing). This chemically undefined material known as “lipofuscin,” “ceroid,” or “age pigment” is mainly formed through unregulated and nonspecific oxidative modifications of cellular macromolecules that are induced by highly reactive free radicals. A necessary precondition for reactive free radical generation and lipofuscin formation is the intracellular availability of ferrous iron (Fe2+) (“labile iron”), catalyzing the conversion of weak oxidants such as peroxides, to extremely reactive ones like hydroxyl (HO•) or alcoxyl (RO•) radicals. If the oxidized materials remain unrepaired for extended periods of time, they can be further oxidized to generate ultimate over-oxidized products that are unable to be repaired, degraded, or exocytosed by the relevant cellular systems. Additionally, over-oxidized materials might inactivate cellular protection and repair mechanisms, thus allowing for futile cycles of increasingly rapid lipofuscin accumulation. In this review paper, we present evidence that the modulation of the labile iron pool distribution by nutritional or pharmacological means represents a hitherto unappreciated target for hampering lipofuscin accumulation and cellular ageing.

Adiponutrin (patatin-like phospholipase domain-containing 3, PNPLA3), encoded in humans by the PNPLA3 gene, is a protein associated with lipid droplet and endoplasmic reticulum membranes, where it is apparently involved in fatty acid redistribution between triglycerides and phospholipids. A common polymorphism of PNPLA3 (I148M, rs738409), linked to increased PNPLA3 presence on lipid droplets, is a strong genetic determinant of non-alcoholic fatty liver disease (NAFLD) and of its progression. P-glycoprotein (Pgp, MDR1, ABCB1), encoded by the ABCB1 gene, is another membrane protein implicated in lipid homeostasis and steatosis. In the past, common ABCB1 polymorphisms have been associated with the distribution of serum lipids but not with fatty acids (FA) profiles. Similarly, data on the effect of PNPLA3 I148M polymorphism on blood FAs are scarce. In this study, a gas chromatography-flame ionization detection (GC-FID) method was optimized, allowing us to analyze twenty FAs (C14: 0, C15: 0, C15: 1, C16: 0, C16: 1, C17: 0, C17: 1, C18: 0, C18: 1cis, C18: 2cis, C20: 0, C20: 1n9, C20: 2, C20: 3n6, C20: 4n6, C20: 5, C23: 0, C24: 0 C24: 1 and C22: 6) in whole blood, based on the indirect determination of the fatty acids methyl esters (FAMES), in 62 hyperlipidemic patients and 42 normolipidemic controls. FA concentrations were then compared between the different genotypes of the rs738409 and rs2032582 (ABCB1 G2677T) polymorphisms, within and between the hyperlipidemic and normolipidemic groups. The rs738409 polymorphism appears to exert a significant effect on the distribution of blood fatty acids, in a lipidemic and fatty acid saturation state-depending manner. The effect of rs2032582 was less pronounced, but the polymorphism did appear to affect the relative distribution of blood fatty acids between hyperlipidemic patients and normolipidemic controls.

Apart from triglycerides, olive oil contains low quantities of polar compounds, such as polyphenols, which are believed to be relevant for maintaining human health. In this presentation, we will discuss potential molecular mechanisms by which specific phenolic compounds present in olive oil can exert cytoprotective and cell signal modulating effects, through chelation of intracellular labile (redox-active) iron. Iron chelation by specific polyphenols can prevent or relocalize the interaction of iron with hydroperoxides produced in the cells and the formation of extremely reactive species. The latter are able, either to induce uncontrolled oxidation of basic cell components or to modulate redox signaling. It is proposed that olive oil–contained polyphenols can influence the outcome of cell responses in conditions of increased oxidative stress mainly by this way.

Journal of molecular biology 433(13), 166954 (2021). doi:10.1016/j.jmb.2021.166954, Von Willebrand Factor (vWF), a 300-kDa plasma protein key to homeostasis, is cleaved at a single site by multi-domain metallopeptidase ADAMTS-13. vWF is the only known substrate of this peptidase, which circulates in a latent form and becomes allosterically activated by substrate binding. Herein, we characterised the complex formed by a competent peptidase construct (AD13-MDTCS) comprising metallopeptidase (M), disintegrin-like (D), thrombospondin (T), cysteine-rich (C), and spacer (S) domains, with a 73-residue functionally relevant vWF-peptide, using nine complementary techniques. Pull-down assays, gel electrophoresis, and surface plasmon resonance revealed tight binding with sub-micromolar affinity. Cross-linking mass spectrometry with four reagents showed that, within the peptidase, domain D approaches M, C, and S. S is positioned close to M and C, and the peptide contacts all domains. Hydrogen/deuterium exchange mass spectrometry revealed strong and weak protection for C/D and M/S, respectively. Structural analysis by multi-angle laser light scattering and small-angle X-ray scattering in solution revealed that the enzyme adopted highly flexible unbound, latent structures and peptide-bound, active structures that differed from the AD13-MDTCS crystal structure. Moreover, the peptide behaved like a self-avoiding random chain. We integrated the results with computational approaches, derived an ensemble of structures that collectively satisfied all experimental restraints, and discussed the functional implications. The interaction conforms to a ���fuzzy complex��� that follows a ���dynamic zipper��� mechanism involving numerous reversible, weak but additive interactions that result in strong binding and cleavage. Our findings contribute to illuminating the biochemistry of the vWF:ADAMTS-13 axis., Published by Elsevier, Amsterdam [u.a.]

We investigate PdCu and PdAg catalysts in the context of oxygenate upgrading for biofuels. To this end, we measure the rates of decarbonylation and hydrogenation of butyraldehyde, the reactive intermediate for the industrially relevant Guerbet condensation, and correlate the selectivity and reactivity with the properties of the catalysts via a range of characterization efforts. Data obtained from EXAFS and XANES show that the bulk of the catalyst metallic nanoparticles is enriched in Pd, while the surface is enriched in Cu and Ag. The data for PdCu show clear dominance of geometric (ensemble) effects on the selectivity. Conversely, the electronic (ligand) effects of alloying dominate over the reaction rate of the catalysts, as electron donation from Cu to Pd promotes the Cu and increases the desired (de)hydrogenation reactions. In contrast, in PdAg catalysts, the weaker electronic exchange, as indicated by Pd L edge XANES and theoretical calculations, is not sufficient to promote Ag, resulting in monotonic loss of activity with increasing Ag content and without selectivity improvement. We use the implications of these findings to provide valuable design principles for oxygenate catalysis and to discover a highly selective bifunctional catalyst system, comprised of a PdCu alloy catalyst and titanium dioxide for the upgrading of ethanol to longer-chain oxygenates.

The development of advanced heat transfer fluids (HTF) with enhanced heat transfer properties has been identified as a key target to increase the efficiency of industrial processes. In this work, heat transfer performance improvements of a novel nanofluid, consisting of metallic nanoparticles dispersed in a commercial thermal oil, were investigated. Nanofluids combining tin nanoparticles (1 mass %) with Therminol 66 (TH66) were synthesised using the two step-method and experimentally analysed. The effectiveness of biosurfactant addition and nanoparticle polyethylene terephthalate (PET) nanocoating for high temperature nanofluid stabilisation were independently investigated. The PET nanoscale coatings were grown by molecular layer deposition, which has been used for the first time in this field. The thermal conductivity, dynamic viscosity and specific heat capacity of the stable, oil-based nanofluids were characterised at high temperatures, and the results were compared and in good agreement with models found in the relevant literature. Finally, the heat transfer performance of the nanofluids with respect to their base fluids was evaluated, employing empirical values for the thermophysical properties of the involved materials. In this way, increments of the heat transfer coefficients up to 9.3% at 140 °C, relevant to industrial applications were obtained.

Based on the air quality in Europe - 2019 report of European Environment Agency, nitrogen oxides (NOx) are included to the most harmful air pollutants in terms of damage to ecosystems. Moreover, NO2 is one of the most Europe’s dangerous pollutants to human health. Anthropogenic emissions of NOx are mainly generated by combustion of fossil fuels. Nitrogen oxides being emitted into the atmosphere cause such environmental problems as acid rains, acidification of soil, lakes and rivers, eutrophication and photochemical smog. The most effective and widely used technology achieved for today to purify flue gases from NOx is selective catalytic reduction using ammonia (NH3-SCR de-NOx). Nowadays, one of the most significant directions in the field of NH3-SCR de-NOx is applying of new nonconventional methods and preparation of new catalysts possessing high specific surface area, uniformity, dispersion of active sites, high activity and selectivity. Atomic layer deposition (ALD) is an attractive technique for deposition of uniformly distributed active catalytic layers or nanoparticles on highly porous substrates being characterized by a complex structure and highly developed surface, where the application of conventional methods (e.g. impregnation or deposition precipitation) can be problematic. The significant advantage of ALD application for preparation of supported catalysts is that the preparation process can be controlled on the atomic scale providing the required thickness of an active layer synthesized with accuracy of up to one atom. Moreover, ALD ensures the formation of catalysts in a gas phase instead of a liquid phase, which enhance the possibility of active species to be deposited inside pores which are very small in size. In this study ALD was applied for preparation of VxOy-based NH3-SCR de-NOx catalysts. Highly porous silica gel powder (63-100μm) with a specific surface area of up to 450 m2·g-1 was used as a substrate for active layer deposition. VxOy/SiO2 with different metal loadings (wt.%) and (VxOy+TiO2)/SiO2 catalysts were prepared by applying the following metal precursors: vanadium (V) tri-i-propoxy oxide (VTIP) and titanium tetrachloride (TiCl4), while deionised water was used as the co-reactant. ICP-OES results revealed that vanadium loadings in VxOy/SiO2 catalysts were 0.3, 0.7, 1.1 and 1.6 wt.%, while the metals loading in the TiO2-promoted VxOy/SiO2 catalyst was 1.04 wt.% and 0.15 wt.% for V and Ti, respectively. According to XPS spectra V2O3 and V2O5 species were identified in the prepared VxOy/SiO2 catalyst with the predominance of vanadium (V) compounds (V2O5/V2O3 ratio was 1.6 and 6.3 for as-synthesized and calcined samples, respectively). V2O5 is found as an active vanadium form for NH3-SCR de-NOx. Additionally, TEM, XRD and BET analyses were conducted to provide a comprehensive characterization of the catalysts prepared.

© The Author(s) 2020., Matrix metalloproteinases (MMPs) occur in 23 human paralogues with key functions in physiology, and their activity is controlled by protein inhibitors. Reversion-inducing cysteine-rich protein with Kazal motifs (RECK), which is essential for embryogenesis and tumour suppression, has been reported to inhibit MMPs. Here, we developed eukaryotic and bacterial expression systems for different RECK variants and analysed their inhibitory capacity against representative MMPs in vitro. We could not detect any significant inhibition. Instead, we found that partially purified RECK from the conditioned medium of transfected Expi293F cells but not that of ExpiCHO-S or Drosophila Schneider cells contained a contaminant with proteolytic activity. The contaminant was removed through treatment with a small-molecule serine peptidase inhibitor and additional chromatographic purification. A tantamount contaminant was further detected in an equivalent expression system of the N-terminal fragment of the proteoglycan testican 3, but not in those of two other proteins. These results indicate that previous reports of inhibitory activity of recombinant RECK on MMPs, which were performed with partially purified samples, were probably masked by a coeluting contaminant present in the supernatant of HEK293-derived cells. Thus, RECK is probably not a direct inhibitor of MMP catalytic activity but may still regulate MMPs through other mechanisms., This study was supported in part by grants from Spanish and Catalan public and private bodies (grant/ fellowship references BFU2015–64487R, MDM-2014–0435, BES-2015–074583, BES-2016–076877, 2017SGR3 and Fundació “La Marató de TV3” 201815).

Table olives are one of the most established Mediterranean vegetables, having an exponential increase consumption year by year. In the natural-style processing, olives are produced by spontaneous fermentation, without any chemical debittering. This natural fermentation process remains empirical and variable since it is strongly influenced by physicochemical parameters and microorganism presence in olive drupes. In the present work, Cypriot green cracked table olives were processed directly in brine (natural olives), using three distinct methods: spontaneous fermentation, inoculation with lactic acid bacteria at a 7% or a 10% NaCl concentration. Sensory, physicochemical, and microbiological alterations were monitored at intervals, and major differences were detected across treatments. Results indicated that the predominant microorganisms in the inoculated treatments were lactic acid bacteria, while yeasts predominated in control. As a consequence, starter culture contributed to a crucial effect on olives fermentation, leading to faster acidification and lower pH. This was attributed to a successful lactic acid fermentation, contrasting the acetic and alcoholic fermentation observed in control. Furthermore, it was established that inhibition of enterobacteria growth was achieved in a shorter period and at a significantly lower salt concentration, compared to the spontaneous fermentation. Even though no significant variances were detected in terms of the total phenolic content and antioxidant capacity, the degradation of oleuropein was achieved faster in inoculated treatments, thus, producing higher levels of hydroxytyrosol. Notably, the reduction of salt concentration, in combination with the use of starter, accented novel organoleptic characteristics in the final product, as confirmed from a sensory panel, hence, it becomes obvious that the production of Cypriot table olives at reduced NaCl levels is feasible.

Background: The effect of leaf removal on postharvest performance of dehydrated grapes has been poorly analyzed. The aim of this study was to evaluate the effect of leaf removal at veraison stage on the metabolites of fresh and dehydrated grapes of two indigenous Cypriot cultivars ('Mavro' and 'Xynisteri'), which are destined for the production of 'Commandaria', a protected designation of origin (PDO) premium sweet wine.; Results: Leaf removal led to a reduction of soluble solids, titratable acidity, aroma potential and most of the phenolic groups in the musts of both cultivars. Dehydration led to a significant increase in all of these parameters in both cultivars, being more pronounced in cv. 'Mavro'. Interestingly, leaf removal indicated differential response in the dehydrated product of the cultivars examined; liquid chromatography (LC-DAD-qTOF-MS) data showed a significant decrease in phenolic compounds in 'Xynisteri' must (from 66.73 to 44.15 mg L-1 ), while 'Mavro' must registered similar values of phenolic compounds (from 94.78 to 96.72 mg L-1 ), but with a different distribution among phenolic groups. Intriguingly, flavonols and flavan-3-ols that present significant health-promoting properties showed higher concentrations in the must from dehydrated 'Mavro' grapes that were subjected to preharvest leaf removal.; Conclusions: Leaf removal at veraison stage followed by sun drying differentially affected the chemical composition of the examined cultivars. This preharvest application followed by postharvest dehydration was beneficial for cv. 'Mavro', while this was not the case for cv. 'Xynisteri'. The effects of leaf removal in other developmental stages (i.e. pre/post bloom stage) need to be dissected with the ultimate goal of providing an end product with high bioactive content. © 2018 Society of Chemical Industry.; © 2018 Society of Chemical Industry.

A critical challenge for the bioenergy research community has been producing drop-in hydrocarbon fuels and chemicals at yields sufficient to compete with their petroleum-derived counterparts. Biological production of highly reduced compounds poses fundamental challenges. Conversely, glucose, xylose, and sucrose can be fermented to ethanol at near-theoretical yields. Just as olefin crackers are often considered a gateway for petrochemical complexes that produce an array of downstream products, catalytic ethanol upgrading can potentially enable an entire biorefining complex able to produce renewable, low-carbon fuels and chemicals. By doping the Ta2O5/SiO2 catalyst with different transition metals, we show that Ostromyslensky catalysts can be utilized for direct conversion of ethanol to varying ratios of 1,3-butadiene (1,3-BD), dietheylether (DEE), and ethylene. These results are integrated into the first comprehensive analysis of ethanol conversion to 1,3-BD, DEE, and ethylene that incorporates empirical d...

The goal of this study was to explore the potential of carob extracts to act as lipid inhibitors in model food systems. First, the extraction efficacy of fourteen solvents on the phenolic and flavonoid contents as well as on the antioxidant activity was assessed. Results showed that the phenolic composition and antioxidant activity of the extracts were strongly affected by solvents. Subsequently, the antioxidant potential of the most promising extracts (water, methanol, acidic acetone, and acetone&ndash, water) against four model food systems were evaluated. The acidic acetone extract had the highest antioxidant activity (70.3 &plusmn, 5.3%) in the &beta, carotene-linoleic acid system, followed by the acetone&ndash, water extract (62.1 &plusmn, 4.9%). Both extracts significantly prevented the lipid oxidation in sunflower oil and cooked comminuted pork, the inhibition activity at the end of storage period was 36.7&ndash, 50.5% and 17.4&ndash, 24.8%, respectively. A reduction of 49.5&ndash, 54.8% in the formation of dienes in the oil-in-water emulsion was also found. The inhibitory effect of methanolic and aqueous extracts was significantly lower. Qualitative and quantitative variations in extracts are responsible for this antioxidant behavior in food systems. Gallic acid, myrecetin, rutin, and catechin are the main components of the extracts while myricetin and quercetin play an essential role in the antioxidant activity, according to the biochromatograms.

The acylation of methylfuran has been investigated using Bronsted and Lewis acid zeolite catalysts. The highest reaction rate for acylation on a per gram basis is found on zeolite Beta with high aluminum content (Si/Al = 23) and the highest turnover frequency on a per metal site basis is found on zeolite Beta with low aluminum content (Si/Al = 138). Among Lewis acid zeolites, [Sn]-Beta shows higher turnover frequency than [Hf]-, [Zr]- or [Ti]-Beta. Similar apparent activation energies were found for [Al]-Beta with different Si/Al ratios and a lower apparent activation energy was found for [Sn]-Beta. Electronic structure calculations reveal that on both [Al]- and [Sn]-Beta the most favorable pathway follows the classic addition-elimination aromatic electrophilic substitution mechanism. The calculations also reveal that, on both [Al]- and [Sn]-Beta, the rate of methylfuran acylation is controlled by the dissociation of the C O C linkage of the anhydride while hydrogen elimination is the rate-determining step in the acylation of furan. The latter is in complete agreement with measured primary kinetic isotope effects. One remarkable and unexpected finding from our calculations is that the most favorable catalytic pathway in [Sn]-Beta involves Bronsted acid catalysis by the silanol group of the hydrolyzed “open” site and not Lewis acid catalysis by the Sn metal center.

Metallopeptidases cleave polypeptides bound in the active-site cleft of catalytic domains through a general base/acid mechanism. This involves a solvent molecule bound to a catalytic zinc and general regulation of the mechanism through zymogen-based latency. Sixty reported structures from 11 metallopeptidase families reveal that prosegments, mostly N-terminal of the catalytic domain, block the cleft regardless of their size. Prosegments may be peptides (5−14 residues), which are only structured within the zymogens, or large moieties (, This study was funded in part by grants from Spanish and Catalan public agencies (BFU2015-64487-R, MDM-2014-0435, and 2017SGR00003). T.G. acknowledges a “Juan de la Cierva” research contract (JCI-2012-13573) from the Spanish Ministry of Economy and Competitiveness. The Structural Biology Unit of IBMB is a“María de Maeztu”Unit of Excellence of the Spanish Ministry of Economy, Industry and Competitiveness.

We study the production of terephthalic acid (TA) from biomass-derived aromatic oxygenates. Among several heterogeneous catalysts tested, a carbon-supported Ir catalyst in 4-heptanone solvent gives the best TA yield from 1,4-dihydroxymethylbenzene. A maximum 76% TA yield is achieved at 100 °C and 12 bar O2. Based on kinetic measurements, we show that the reaction progresses in two distinct pathways. First, the alcohol groups of the substrate are converted to the aldehydes via an O-assisted dehydrogenation pathway over Ir, and then the aldehydes are oxidized to the acid in the solution via a free radical mechanism. We demonstrate that it is easier to oxidize aromatic diols than p-xylene over a heterogeneous catalyst, and thus, the biomass route to TA may be an attractive alternative to the commercial crude oil-based process.

The design of selective and active heterogeneous catalysts for the hydrodeoxygenation (HDO) of biomass-derived platform molecules requires understanding of the catalyst structure under reaction conditions. In this work, we design, build and qualify an operando X-ray absorption (XAS) cell to characterize a highly selective NiCu3 catalyst under HDO conditions. We complement XAS measurements with X-ray photoelectron spectroscopy (XPS) studies and theoretical calculations to show that in bimetallic NiCu catalysts, Ni and Cu are segregated. The as-made catalysts are mixed oxides, with a NiO shell over a NiCuOx core. The core becomes a partially reduced metal alloy after treatment with hydrogen at temperatures below 473 K, while the shell becomes fully reduced at higher treatment temperatures. The liquid-phase reaction results in gradual reoxidation of the catalyst to a core–shell mixed oxide, in which the Cu in the core is predominately Cu(I) and the Ni shell is predominately Ni(II).

The objective of this study was to compare the effect of traditional sun-drying method (TM) with four alternative dehydration methods [(a) multiple horizontal wires (MHW), (b) multiple vertical pallets (MVP), (c) low greenhouse (LGH) and (d) hot-air dryer treatment (HAD)] on phenolic composition, oenological parameters, aroma potential and browning compounds of musts obtained from dehydrated grapes (Vitis vinifera cv. ‘Xynisteri’). Dehydrated grapes of the examined cultivar are being used to produce ‘Commandaria’ dessert wine, a protected designation of origin product in Cyprus. LGH and HAD treatments led to a significant reduction of the dehydration period. Soluble solid contents were used to monitor the progress of dehydration process; no changes among the examined dehydration methods in reducing sugar composition were found. Notably, HAD led to a dramatic rise (3.2-fold) of titratable acidity that was obviously not related only to the concentration effect. Furthermore, all dehydration methods concentrated total bound volatiles and induced the formation of brown pigments. Based on the Folin-Ciocalteu index, only HAD and LGH induced a significant increase in total phenolic content in dehydrated grape musts. Subsequently, forty phenolic compounds were identified and quantified by LC-DAD-qTOF-MS. Results showed a significant effect of dehydration methods that vary according to the different groups of phenolic compounds considered. Similarly to Folin-Ciocalteu index, HAD and LGH methods increased significantly the phenolic content in grape musts, whereas MHW and MVP methods increased it slightly higher than the concentration factor. Flavonols, flavan-3-ols and flavanonols were the most affected polyphenolic groups. A significant increment of hydroxybenzoic and hydroxycinnamic acids, the predominant groups of phenolic compounds found in ‘Xynisteri’ grapes, was monitored. Taking into consideration that HAD cannot be exploited under the existing legal framework, LGH showed the greatest potential for the production of high quality dehydrated ‘Xynisteri’ grape must.

Background/Aim: A previous study revealed that the inclusion of grape pomace (GP) in the diet for growing lambs had beneficial effects on the redox status and fecal microbiota. Herein, we investigated the effect of GP inclusion on performance, carcass traits and fatty acid composition of meat. Materials and Methods: In the experimental trial of 55 days, lambs were fed with standard or diet supplemented with GP. Performance, carcass traits and fatty acid profile of quadriceps muscle were assessed. Results: GP inclusion in the diet improved growth performance, since the average daily gain was significantly increased by 2-fold in GP group. Regarding the fatty acid composition of meat, GP inclusion significantly increased the content of long chain n-3 fatty acids, eicosapentaenoic acid and docosahexaenoic acid, and reduced the n-6/n-3 ratio compared to the control group. Conclusion: GP supplementation in lamb diet may improve performance and may have beneficial effects on meat quality.

The aim of this study was to understand the antioxidant metabolic changes of peach (cvs. ‘Royal Glory’, ‘Red Haven’ and ‘Sun Cloud’) and nectarine fruits (cv. ‘Big Top’) exposed to different combinations of low-temperature storage (0, 2, 4 weeks storage at 0 °C, 90% R.H.) and additional ripening at room temperature (1, 3 and 5 d, shelf life, 20 °C) with an array of analytical, biochemical and molecular approaches. Initially, harvested fruit of the examined cultivars were segregated non-destructively at advanced and less pronounced maturity stages and qualitative traits, physiological parameters, phytochemical composition and antioxidant capacity were determined. ‘Big Top’ and ‘Royal Glory’ fruits were characterized by slower softening rate and less pronounced ripening-related alterations. The coupling of HPLC fingerprints, consisted of 7 phenolic compounds (chlorogenic, neochlorogenic acid, catechin, epicatechin, rutin, quecetin-3-O-glucoside, procyanidin B1) and spectrophotometric methods disclosed a great impact of genotype on peach bioactive composition, with ‘Sun Cloud’ generally displaying the highest contents. Maturity stage at harvest did not seem to affect fruit phenolic composition and no general guidelines for the impact of cold storage and shelf-life on individual phenolic compounds can be extrapolated. Subsequently, fruit of less pronounced maturity at harvest were used for further molecular analysis. ‘Sun Cloud’ was proven efficient in protecting plasmid pBR322 DNA against ROO[rad] attack throughout the experimental period and against HO[rad] attack after 2 and 4 weeks of cold storage. Interestingly, a general down-regulation of key genes implicated in the antioxidant apparatus with the prolongation of storage period was recorded; this was more evident for CAT, cAPX, Cu/ZnSOD2, perAPX3 and GPX8 genes. Higher antioxidant capacity of ‘Sun Cloud’ fruit could potentially be linked with compounds other than enzymatic antioxidants that further regulate peach fruit ripening.

A library of diverse heparan sulfate (HS) oligosaccharides was chemoenzymatically synthesized and systematically studied using NMR., Heparan sulfate (HS) is a member of the glycosaminoglycans (GAG) family that plays essential roles in biological processes from animal sources. Heparin, a highly sulfated form of HS, is widely used as anticoagulant drug worldwide. The high diversity and complexity of HS and heparin represent a roadblock for structural characterization and biological activity studies. Access to structurally defined oligosaccharides is critical for the successful development of HS and heparin structure–activity relationships. In this study, a library of 66 HS and heparin oligosaccharides covering different sulfation patterns and sizes was prepared through an efficient method of chemoenzymatic synthesis. A systematic nuclear magnetic resonance spectroscopy study was firstly undertaken for every oligosaccharide in the library. In addition to the availability of different oligosaccharides, this work also provides spectroscopic data helpful for characterizing more complicated polysaccharide structures providing a safeguard to ensure the quality of the drug heparin. This HS/heparin library will be useful for activity screening and facilitate future structure–activity relationship studies.

Peptidases must be exquisitely regulated to prevent erroneous cleavage and one control is provided by protein inhibitors. These are usually specific for particular peptidases or families and sterically block the active-site cleft of target enzymes using lock-and-key mechanisms. In contrast, members of the +1400-residue multi-domain α2-macroglobulin inhibitor family (α2Ms) are directed against a broad spectrum of endopeptidases of disparate specificities and catalytic types, and they inhibit their targets without disturbing their active sites. This is achieved by irreversible trap mechanisms resulting from large conformational rearrangement upon cleavage in a promiscuous bait region through the prey endopeptidase. After decades of research, high-resolution structural details of these mechanisms have begun to emerge for tetrameric and monomeric α2Ms, which use ‘Venus-flytrap’ and ‘snap-trap’ mechanisms, respectively. In the former, represented by archetypal human α2M, inhibition is exerted through physical entrapment in a large cage, in which preys are still active against small substrates and inhibitors that can enter the cage through several apertures. In the latter, represented by a bacterial α2M from Escherichia coli, covalent linkage and steric hindrance of the prey inhibit activity, but only against very large substrates., This study was supported in part by grants from European, Spanish, and Catalan agencies (grant references FP7-HEALTH-2012-306029-2 ‘TRIGGER’, BFU2015-64487R, MDM-2014-0435, BIO2013-49320-EXP, and 2014SGR9). The Structural Biology Unit (www.sbu.csic.es) of IBMB has been named a ‘María de Maeztu’ Unit of Excellence by the Spanish Ministry of Economy and Competitiveness. T.G. and I.G.-F. acknowledge a ‘Juan-dela-Cierva’ contract from the Spanish Ministry of Economy and Competitiveness (JCI-2012-13573) and an FPU fellowship from the Spanish Ministry of Education and Culture (AP-2010-03799), respectively

The C18 column (250 mm × 4.6 mm) packed with 5 μm core-shell particles was used in an effort to optimize the separation of 8 polycyclic aromatic hydrocarbons under very low pressure values (44–52 bars), low temperature (16 °C) and in 13 min. Chromatogram and peaks of each polycyclic aromatic hydrocarbon studied, obtained using an ultra fast liquid chromatography fitted with this column and equipped with a diode array detector, were compared with those obtained using two other traditional C18 columns, packed with fully porous 5 μm particles, usually used in our laboratory and specifically designed for the separation of polycyclic aromatic hydrocarbons. Thinnest peaks, highest sensitivity and efficiency are the main results related to the core-shell technology of the recent Kinetex column compared to more common C18 columns due to the bed uniformity and packing quality of the recent core-shell column. On the other hand, reduced retention time was highlighted for each polycyclic aromatic hydrocarbon using the column packed with core-shell particles resulting from the lower surface area of these particles compared to the totally porous particles of the both other columns used. Limits of detection and quantification, linearity range and repeatability were determined for the method developed with the core-shell column. A practical application was realized by evaluating the sorption capacity of the 8 polycyclic aromatic hydrocarbons studied in mixture using a biochar made from woody plants. To this end, the biochar was mixed with aqueous solution spiked with the mixture of polycyclic aromatic hydrocarbons and a kinetic study of their sorption was conducted. Sorption percentage was higher than 89% for each polycyclic aromatic hydrocarbon studied showing that the studied biochar could be good and low cost alternative products for the sorption of this type of pollutants.

In normal B-cells, Bruton tyrosine kinase (Btk), a non-receptor tyrosine kinase involved in B-cell receptor (BCR) signalling, is essential for cell survival and maturation. Not surprisingly, Btk is also implicated in the pathogenesis of B-cell lymphomas, like Chronic Lymphocytic Leukaemia/Small Lymphocytic Lymphoma (CLL/SLL), Mantle Cell Lymphoma (MCL) and Waldenström’s Macroglobulinemia (WM), which are driven by aberrant BCR signalling. Thus, targeting Btk represents a promising therapeutic strategy in the treatment of B-cell lymphoma patients. Ibrutinib, a selective Btk inhibitor, has already been approved as second-line treatment of CLL/SLL, MCL and WM patients, while more clinical studies of ibrutinib and novel Btk inhibitors are currently under way. In light of results of the RESONATE-2 trial, the approval of ibrutinib as a first-line treatment of CLL/SLL may well be approaching. Herein, we review Btk’s role in normal and malignant BCR signalling, as well as ibrutinib’s performance in B-cell lymphoma treatment and prognosis.

Author(s): Goulas, KA; Gunbas, G; Dietrich, PJ; Sreekumar, S; Grippo, A; Chen, JP; Gokhale, AA; Toste, FD | Abstract: Herein, we present work on the catalyst development and the kinetics of acetone-butanol-ethanol (ABE) condensation. After examining multiple combinations of metal and basic catalysts reported in the literature, Cu supported on calcined hydrotalcites (HT) was found to be the optimal catalyst for the ABE condensation. This catalyst gave a six-fold increase in reaction rates over previously reported catalysts. Kinetic analysis of the reaction over CuHT and HT revealed that the rate-determining step is the C−H bond activation of alkoxides that are formed from alcohols on the Cu surface. This step is followed by the addition of the resulting aldehydes to an acetone enolate formed by deprotonation of the acetone over basic sites on the HT surface. The presence of alcohols reduces aldol condensation rates, as a result of the coverage of catalytic sites by alkoxides.

A novel one-step process for catalytic production of succinic acid from tartaric acid, which is largely available in the waste streams of wine making, is developed. A liquid-phase system comprised of a molybdenum oxide catalyst supported on carbon black (MoOx/BC) and hydrobromic acid in acetic acid under a H2 atmosphere is effective for selective cleavage of the C–O bonds of tartaric acid and selective hydrogenation of the resulting unsaturated carbons. Temperature, hydrogen pressure, and catalyst pre-treatment are optimized to understand their impact on catalytic activity and product distribution, leading to an 87% yield of succinic acid at 170 °C. Importantly, reduction of the carboxyl groups and C–C bond cleavage are retarded. Pre-reduction and characterization studies (TPR, XRD, XPS, and XAS) reveal that the high catalyst activity of MoOx/BC is correlated with the lower Mo oxidation states (+4 to 0) formed during pre-reduction that promote cleavage of the C–O bonds of tartaric acid and hydrogenation of the CC bond of the intermediate fumaric acid. Recyclability studies and structural characterization of the recovered catalyst indicate that MoOx/BC remains active upon reuse.

Heparan sulfate (HS) is a member of the glycosaminoglycans (GAG) family that plays essential roles in biological processes from animal sources. Heparin, a highly sulfated form of HS, is widely used as anticoagulant drug worldwide. The high diversity and complexity of HS and heparin represent a roadblock for structural characterization and biological activity studies. Access to structurally defined oligosaccharides is critical for the successful development of HS and heparin structure-activity relationships. In this study, a library of 66 HS and heparin oligosaccharides covering different sulfation patterns and sizes was prepared through an efficient method of chemoenzymatic synthesis. A systematic nuclear magnetic resonance spectroscopy study was firstly undertaken for every oligosaccharide in the library. In addition to the availability of different oligosaccharides, this work also provides spectroscopic data helpful for characterizing more complicated polysaccharide structures providing a safeguard to ensure the quality of the drug heparin. This HS/heparin library will be useful for activity screening and facilitate future structure-activity relationship studies.

The cationic statistical copolymerization of n-butyl (be) and 2-chloroethyl vinyl ether (CEVE), is efficiently conducted using bis(&eta, 5-cyclopentadienyl)dimethyl zirconium (Cp2ZrMe2) in combination with tetrakis(pentafluorophenyl)borate dimethylanilinum salt [B(C6F5)4]&ndash, [Me2NHPh]+, as an initiation system. The reactivity ratios are calculated using both linear graphical and non-linear methods. Structural parameters of the copolymers are obtained by calculating the dyad sequence fractions and the mean sequence length, which are derived using the monomer reactivity ratios. The glass transition temperatures (Tg) of the copolymers are measured by Differential Scanning Calorimetry (DSC), and the results are compared with predictions based on several theoretical models. The statistical copolymers are further employed as scaffolds for the synthesis of graft copolymers having poly(vinyl ether)s as a backbone and either poly(&epsilon, caprolactone) (PCL) or poly(l-lactide) (PLLA) as side chains. Both the grafting &ldquo, onto&rdquo, and the grafting &ldquo, from&rdquo, methodologies are employed. The reaction sequence is monitored by Size Exclusion Chromatography (SEC), NMR and IR spectroscopies. The advantages and limitations of each approach are thoroughly examined.

The food industry has become interested in the development of innovative biomaterials with antioxidant and antimicrobial properties. Although several biopolymers have been evaluated for food packaging, the use of polyphenolic coatings has been unexplored. The purpose of this work was to develop an antioxidant and antimicrobial coating for food packaging through the polymerization of carob phenolics. At first, the polyphenolic coatings were deposited in glass surfaces polymerizing different concentrations of carob extracts (2 and 4 mg mL&minus, 1) at three pH values (7, 8 and 9). Results demonstrated that the coating produced at pH 8 and at a concentration of 4 mg mL&minus, 1 had the most potent antioxidant and antimicrobial potential. Then, the coating was applied directly on the salmon fillet (coating) and on the plastic container (active packaging). Peroxide and thiobarbituric acid-reactive substances (TBARS) methods were used to measure the potency to inhibit lipid oxidation in salmon fillets. Furthermore, the anti-Listeria activity of coatings was also assessed. Results showed a significant decrease of lipid oxidation during cold storage of salmon fillets for both treatments, the superiority of applied coating directly on the salmon fillets was also highlighted. Regarding the antimicrobial potency, the polyphenolic coating depleted the growth of Listeria monocytogenes after 10 days storage, while the active packaging had no effect on Listeria monocytogenes. Overall, we describe the use of low-cost carob polyphenols as precursors for the formation of bifunctional coatings with promising applications in food packaging.

© The Author(s) 2019., α2-Macroglobulins (α2Ms) regulate peptidases, hormones and cytokines. Mediated by peptidase cleavage, they transit between native, intact forms and activated, induced forms. α2Ms have been studied over decades using authentic material from primary sources, which was limited by sample heterogeneity and contaminants. Here, we developed high-yield expression systems based on transient transfection in Drosophila Schneider 2 and human Expi293F cells, which produced pure human α2M (hα2M) at ~1.0 and ~0.4 mg per liter of cell culture, respectively. In both cases, hα2M was mainly found in the induced form. Shorter hα2M variants encompassing N-/C-terminal parts were also expressed and yielded pure material at ~1.6/~1.3 and ~3.2/~4.6 mg per liter of insect or mammalian cell culture, respectively. We then analyzed the binding of recombinant and authentic hα2M to recombinant latent human transforming growth factor-β2 (pro-TGF-β2) and bacterial G-related α2M binding protein (GRAB) by surface plasmon resonance, multiple-angle laser light scattering, size-exclusion chromatography, fluorogenic labelling, gel electrophoresis and Western-blot analysis. Two GRAB molecules formed stable complexes of high affinity with native and induced authentic hα2M tetramers. The shorter recombinant hα2M variants interacted after preincubation only. In contrast, pro-TGF-β2 did not interact, probably owing to hindrance by the N-terminal latency-associated protein of the cytokine., This study was supported in part by grants from Spanish and Catalan public and private bodies (grant/fellowship references BFU2015-64487R; MDM-2014-0435; JCI-2012-13573; BES-2015-074583; BES2013-064651; 2017SGR3; and Fundació “La Marató de TV3” 201815). Te Structural Biology Unit of IBMB is a “María de Maeztu” Unit of Excellence from the Spanish Ministry of Science, Innovation and Universities.