High-performance liquid chromatography-diode array detector determination and availability of phenolic compounds in 10 genotypes of walnuts

Walnuts contain signi?cant amounts of bioactive compounds such as polyphenols. The aim of the present study was to determine the differences in phenolic composition and polyphenolic in vitro availability of 10 genotypes of walnuts. All analyzed genotypes showed high flavonoid and non-flavonoid phenolic compounds, especially Eureka and Tehama genotypes. Ellagic acid and syringic acid were the mayor non-flavonoids. Regarding flavonoids, catechin and procyanidin B₂ were the most abundant, covering about 98% of total flavonoids. The in vitro digestion showed flavonoids as the most available polyphenols, especially catechin, gallocatechin, and epigallocatechin gallate.     

Escitalopram Targets Oxidative Stress,Caspase-3, BDNF and MeCP2 in the Hippocampus and Frontal Cortex of a Rat Model of Depression Induced by Chronic Unpredictable Mild Stress

In recent years, escitalopram (ESC) has been suggested to have different mechanisms of action beyond its well known selective serotonin reuptake inhibition. The aim of this study is to investigate the effects of escitalopram on oxidative stress, apoptosis, brain-derived neurotrophic factor (BDNF), Methyl-CpG-binding protein 2 (MeCP2), and oligodendrocytes number in the brain of chronic unpredictable mild stress-induced depressed rats. The animals were randomised in four groups (8 in each group): control, stress, stress + ESC 5 and stress + ESC 5/10. ESC was administered for 42 days in a fixed dose (5 mg/kg b.w.) or in an up-titration regimen (21 days ESC 5 mg/kg b.w. then 21 days ESC 10 mg/kg b.w.). Sucrose preference test (SPT) and elevated plus maze (EPM) were also performed. ESC improved the percentage of sucrose preference, locomotion and anxiety. ESC5/10 reduced the oxidative damage in the hippocampus and improved the antioxidant defence in the hippocampus and frontal lobe. ESC5/10 lowered caspase 3 activity in the hippocampus. Escitalopram had a modulatory effect on BDNF and the number of oligodendrocytes in the hippocampus and frontal lobe and also improved the MeCP2 expressions. The results confirm the multiple pathways implicated in the pathogenesis of depression and suggest that escitalopram exerts an antidepressant effect via different intricate mechanisms.     

Experimental Study of the Sb-Sn-Zn Alloy System

The Sb-Sn-Zn alloy was prepared and researched by experimental methods, which allow obtaining information on the thermodynamic stability of the coexisting phases. Thermal analysis was used to determine the phase transition temperatures of experimental alloys. Equilibrium composition of coexisting phases after long-term temperature equilibration was determined by electron microscopy. The existence of one ternary stoichiometric phase Sb₂SnZn was experimentally confirmed by diffraction technique. The CALPHAD method for prediction of the phase diagram of the Sb-Sn-Zn system from binary subsystems was used in this work.     

Study of the effect of different iron salts used to fortify infant formulas on the bioavailability of trace elements using ICP-OES

Five different iron salts—sulphate, lactate, diphosphate, encapsulated sulphate, and EDTA-Fe(III)—were used to fortify an infant formula to study possible differences in iron bioavailability. The effect of iron fortification at two levels (0.5 mg Fe 100 kcal⁻¹ and 1.5 mg Fe 100 kcal⁻¹) on the bioavailability of other important trace elements such as copper and zinc were also evaluated. An in vitro method based on element dialysability (i.e., the fraction available by absorption) to simulate newborn digestion was applied to study iron, copper and zinc bioavailability. Enzyme treatment was carried out in two stages involving pepsin at pH 5.0 followed by pancreatin at pH 7.0. The incubation times were short to mimic the transit of meal in an infant's gastrointestinal tract. Iron, copper and zinc were determined using inductively coupled plasma atomic emission spectrometry using an axially configured device. The percentages of Fe, Cu and Zn dialysable at both iron fortification levels are discussed. From these results, EDTA-Fe (III) appears to be the most adequate salt for iron fortification of infant formulas.     

STEPWISE INTERCALATION OF PIPERJDINE IN LAYERED α- AND γ- HAFNIUM PHOSPHATE

ABSTRACT

The mechanism of intercalation of piperidine in α-hafnium phosphate, Hf(HPO₄;V) ₂H₂O (dooz = 7.6 [Adot]) and γ-hafnium phosphate, Hf(P0₄)(H₂P0₄) 2H₂0 (doo2 - 12.1 [Adot]), has been investigated by the batch method. Saturated phases were not obtained. The reactions take place stepwise with the final formation of the compounds Hf(HPO₄) ₂ C₅H₁₁N H₂O and Hf[P0₄)(H₂P0₄)C₅ H₁₁ N 2H₂0. In the α-HfP case, no intermediate phases have been detected but in the γ-HfP case, a new phase, Hf(PO₄)(H₂PO₄)0.38C₅H₁₁N 2H₂O, was isolated The characterization of the intercalates was made by chemical and thermal analysis, X-ray diffraction and 1R spectroscopy. Materials with a monolaminar arrangement of amine molecules in the phosphate interlayer region were obtained and the results are compared to those described using different intercalation conditions.     

Monolayer Silane‐Coated,Water‐Soluble Quantum Dots

A one‐step method to produce ≈12 nm hydrodynamic diameter water‐soluble CdSe/ZnS quantum dots (QDs), as well as CdS/ZnS, ZnSe/ZnMnS/ZnS, AgInS₂/ZnS, and CuInS₂/ZnS QDs, by ligand exchange with a near‐monolayer of organosilane caps is reported. The method cross‐links the surface‐bound silane ligands such that the samples are stable on the order of months under ambient conditions. Furthermore, the samples may retain a high quantum yield (60%) over this time. Several methods to functionalize aqueous QD dispersions with proteins and fluorescent dyes have been developed with reaction yields as high as 97%.     

Co-occurrence of aflatoxins,ochratoxin A and zearalenone in breakfast cereals from spanish market

Forty-six breakfast cereal samples from the Spanish market have been analyzed for the occurrence of aflatoxins (AFB1, AFG1, AFB2 and AFG2), ochratoxin A (OTA) and zearalenone (ZEA). According to the results, 9% of the samples were contaminated with AFB1 although no sample exceeded the LOQ (0.2 μg kg^?1), and no sample presented detectable levels of the other aflatoxins (AFB2, AFG1 and AFG2). Zearalenone and OTA contaminated 48 and 39% of the samples, respectively, with mean values of the samples having quantification levels of 25.40 and 0.37 μg kg^?1, respectively. The co-occurrence of OTA and ZEA was observed in 28% of the samples. Aflatoxin B1 appeared only in the corn-based breakfast cereals, whereas ZEA and OTA showed the highest contamination rates in the samples containing wheat and wheat and rice, respectively. No sample of high-fiber content was contaminated with AFB1, whereas OTA and ZEA occurred with higher incidence in high-fiber content samples. Moreover, the daily exposure to AFB1, OTA and ZEA is discussed.     

Patterns on growing square domains via mode interactions

Numerical simulations of reaction-diffusion systems with Neumann boundary conditions (NBC) on growing square domains by Maini et al. exhibit square and stripe (or roll) patterns that are usually associated with bifurcations from a trivial equilibrium on a square lattice. However, these patterns change as the domain grows. In this article we discuss several of these transitions; namely, transitions between different types of squares and between squares and stripes (or rolls). We show that these transitions can be understood by tracing paths through the unfoldings of certain co-dimension two mode interactions. To understand these transitions, we need to discuss two issues: the speed at which the domain size changes and the relations between NBC and periodic boundary conditions (PBC) on a square. First, in the simulations, the domain growth takes place on a time scale that is longer than the one needed for pattern formation. Therefore, we can assume that the domain growth is identified with quasistatic variation of time; that is, the domain grows slowly enough that the PDE solution of the time-dependent system tracks equilibria of the reaction-diffusion systems posed on a fixed size domain. Second, as is well-known, NBC problems on a square of side length l can be embedded in PBC problems on a square with side length 2l. The PBC problem has translation symmetries that are not present in the NBC problem. These additional symmetries are called hidden symmetries in the literature. Moreover, solutions to PBC that restrict to the smaller square and satisfy NBC are just those solutions that satisfy certain symmetry constraints. We show further that the transitions between different patterns can be understood by considering relevant mode interaction bifurcation problems on the larger square and then restricting to the smaller square. We have found that a generic continuous transition can occur between two types of squares. Also, the transition between squares and stripes can generically occur either via steady states and time-periodic states (standing waves) or via a jump. Interestingly, in mode interactions, the symmetry constraints induced by NBC are important in understanding which solutions exist and which solutions are stable. For example, diagonal stripes cannot occur as a primary branch in the NBC problem but do in the PBC problem. Also, patterns can be stable in the NBC problem that are not stable in the PBC problem. As a consequence, in the NBC problem we see standing wave time-periodic solutions as stable patterns leading to stable stripes, whereas in the PBC problem we see wavy rolls steady states as stable patterns leading to stable stripes. In principle, a classification of all transitions in NBC mode interactions is possible. However, we concentrate only on those transitions that are relevant to the numerically observed transitions.     

Cross‐linking of bovine and caprine caseins by microbial transglutaminase and their use as microencapsulating agents for n‐3 fatty acids

Bovine and caprine caseins were cross‐linked with microbial transglutaminase (mTG). The mTG‐cross‐linked bovine or caprine casein dispersion, mixed with 14.5% maltodextrin (DE = 40), was used to prepare emulsions with 10.5% algae oil. Oxidative stability of emulsions was evaluated by peroxide values (PVs) and anisidine values. Adding liposoluble rosemary extract rich in carnosic acid and δ‐tocopherol lowered the formation of hydroperoxides and their subsequent decomposition products in emulsions. Emulsions stabilised with liposoluble rosemary extract rich in carnosic acid and δ‐tocopherol were spray‐dried at 180/95 °C. Algae oil microencapsulated with mTG‐cross‐linked bovine casein reduced PV by ≈ 34%, while the algae oil microencapsulated with mTG‐cross‐linked caprine casein with low levels of α_s1‐casein reduced PV by ≈ 42% at 4 weeks of storage at 30 °C. The investigation suggests that liposoluble rosemary extract rich in carnosic acid and δ‐tocopherol effectively protected algae oil during the coating process with mTG‐cross‐linked bovine and caprine caseins. The above results clearly indicated that the choice of milk caseins (bovine vs. caprine) cross‐linked with mTG impacts the oxidative stability of spray‐dried algae oil emulsions (microcapsules) enriched with n‐3 fatty acids.