One‐Pot Hydroacetylation of Menadione (Vitamin K3) to Menadiol Diacetate (Vitamin K4) by Heterogeneous Catalysis

Vitamin K₄ (menadiol diacetate, MDD) can be easily synthesized through cleaner and more efficient catalytic alternatives following the green chemistry principles. Ionic gold‐based hydroxylated fluorides are active bi‐functional catalysts for the one‐pot hydroacetylation of menadione leading to MDD with 77% selectivity. Unprecedent results were obtained in the presence of oxide‐fluoride catalysts by using a microwave‐assisted hydrogen‐transfer (Meerwein–Ponndorf–Verley reaction) coupled with an acetylation approach, yielding very high selectivities for the target product (95%).     

Antibacterial activity of silver-doped hydroxyapatite nanoparticles against gram-positive and gram-negative bacteria

Ag-doped nanocrystalline hydroxyapatite nanoparticles (Ag:HAp-NPs) (Ca_10-xAg_x(PO₄)₆(OH)₂, x_Ag = 0.05, 0.2, and 0.3) with antibacterial properties are of great interest in the development of new products. Coprecipitation method is a promising route for obtaining nanocrystalline Ag:HAp with antibacterial properties. X-ray diffraction identified HAp as an unique crystalline phase in each sample. The calculated lattice constants of a = b = 9.435 Å, c = 6.876 Å for x_Ag = 0.05, a = b = 9.443 Å, c = 6.875 Å for x_Ag = 0.2, and a = b = 9.445 Å, c = 6.877 Å for x_Ag = 0.3 are in good agreement with the standard of a = b = 9.418 Å, c = 6.884 Å (space group P6₃/m). The Fourier transform infrared and Raman spectra of the sintered HAp show the absorption bands characteristic to hydroxyapatite. The Ag:HAp nanoparticles are evaluated for their antibacterial activity against Staphylococcus aureus, Klebsiella pneumoniae, Providencia stuartii, Citrobacter freundii and Serratia marcescens. The results showed that the antibacterial activity of these materials, regardless of the sample types, was greatest against S. aureus, K. pneumoniae, P. stuartii, and C. freundii. The results of qualitative antibacterial tests revealed that the tested Ag:HAp-NPs had an important inhibitory activity on P. stuartii and C. freundii. The absorbance values measured at 490 nm of the P. stuartii and C. freundii in the presence of Ag:HAp-NPs decreased compared with those of organic solvent used (DMSO) for all the samples (x_Ag = 0.05, 0.2, and 0.3). Antibacterial activity increased with the increase of x_Ag in the samples. The Ag:HAp-NP concentration had little influence on the bacterial growth (P. stuartii).     

Alignment of the dye's molecular levels with the TiO(2) band edges in dye-sensitized solar cells: a DFT-TDDFT study

We present a theoretical study of the lineup of the LUMO of Ru(II)-polypyridyl (N3 and N719) molecular dyes with the conduction band edge of a TiO(2) anatase nanoparticle. We use density functional theory (DFT) and the Car-Parrinello scheme for efficient optimization of the dye-nanoparticle systems, followed by hybrid B3LYP functional calculations of the electronic structure and time-dependent DFT (TDDFT) determination of the lowest vertical excitation energies. The electronic structure and TDDFT calculations are performed in water solution, using a continuum model. Various approximate procedures to compute the excited state oxidation potential of dye sensitizers are discussed. Our calculations show that the level alignment for the interacting nanoparticle-sensitizer system is very similar, within about 0.1?eV, to that for the separated TiO(2) and dye. The excellent agreement of our results with available experimental data indicates that the approach of this work could be used as an efficient predictive tool to help the optimization of dye-sensitized solar cells.     

Evaluation of the oxidation state and metal concentration in the adipose tissue of Parma ham

The effect of different dietary fat supplements: A, no added fat; B, 3% added lard and C, 3% added partially hydrogenated lard (PHL), were evaluated in dry cured Parma ham fat by determination of the lipid oxidation indices, R1 and R2, on a total of 30 Italian Landrace×Italian Large White pigs. Furthermore, correlations between lipid oxidation and calcium, magnesium, iron, zinc, copper and nickel concentrations, determined in Parma ham fat, was also investigated. Results highlighted a correlation between the oxidative state of Parma ham fat and the pigs' diet; in particular the addition of 3% PHL led to a more stable depot fat towards lipid oxidation compared to the addition of lard. Finally, Parma ham fat from treatment C showed higher concentrations of Ca (p<0.01) and Mg (p<0.05) compared to those from control, A, and treatment B groups. On the contrary, no significant differences were found for Fe, Zn, Cu and Ni.     

Stabilisation of sunflower oil and reduction of acrylamide formation of potato with rosemary extract during deep-fat frying

The aim of this study was to evaluate the effects of rosemary extract on the stabilisation of sunflower oil and the reduction of acrylamide formation in potato during deep-fat frying. The synthetic antioxidants butylated hydroxyanisole, tertiary butylhydroquinone, and tocopherols served as positive controls. Thermo-oxidative alterations were measured according to various physical and chemical parameters. Total polar compounds, free fatty acids, conjugated dienes, conjugated trienes, and colour (L*, b*) were evaluated for effectiveness of the antioxidants to stabilise the sunflower oil. The acrylamide concentration was evaluated for effectiveness of the antioxidants to reduce the acrylamide content in the deep-fried potato. Except for the decreased L* value (darkness of oil colour), these parameters all increased with the number of frying cycles. The order of effectiveness for inhibition of sunflower oil degradation and reduction of acrylamide formation in deep-fried potato was: rosemary extract > tocopherols > tertiary butylhydroquinone > butylated hydroxyanisole > control (P < 0.05). Total polar compounds, free fatty acid and acrylamide levels were significantly correlated with frying time (P < 0.05). The acrylamide formation in fried potatoes was significantly correlated with the formation of total polar compounds (P < 0.05) in the frying oil during the frying process.     

Validation of a method for composition measurement of a non-standard liquid fuel for Emission Factor evaluation

In this paper the theoretical and experimental aspects are described concerning the validation of a method for the measurement of the percentage composition of a generic liquid fuel, even though specific reference materials for instrumentation calibration are unavailable. This new method could be used for the evaluation of the Emission Factor (EF) of an unknown fuel for emission trading purposes, according to the requirements of both the juridical and technical standards. The validation of the procedure is based on the comparison of different techniques for the measurement of Gross Calorific Value (GCV), Net Calorific Value (NCV) which are quantities useful in EF evaluation; this new combination of actions established a complete and validated methodology for EF evaluation. The experimental results and uncertainty analysis show that this method is suitable for the estimation of the composition measurement and also that of GCV, NCV and EF also for non-standard liquid fuels; a comparable accuracy with respect to the methods for standard fuels has been estimated, making this method suitable for practical applications.     

Substituted isoxazoles as potent inhibitors of p38 MAP kinase

In a continuous effort to develop improved p38 MAP (mitogen-activated protein) kinase inhibitors, we focused our attention on the suitability of the isoxazole ring as a bioisosteric replacement for the imidazole ring of SB-203580. 3,4- and 4,5-disubstituted as well as 3,4,5-trisubstituted isoxazole derivatives were synthesized. These compounds were tested in an in vitro enzyme-linked immunosorbent assay of isolated p38 MAP kinase and for inhibitory potency against cytochrome P450. Compound 4 a displays a highly promising profile for development as an anti-inflammatory agent owing to its enhanced suppression of cytokine release, decreased affinity for cytochrome P450 and a twofold decrease in IC50 toward isolated p38 MAP kinase.     

Galactose derivative immobilized glow discharge processed polyethersulfone membranes maintain the liver cell metabolic activity

New strategies aimed to surface modification of polymeric membranes are crucial to optimise cell-biomaterial interactions in vivo and in vitro biohybrid systems. In this paper, we investigated the surface modification of Polyethersulfone (PES) membranes by plasma polymerisation of acrylic acid monomers (PES-pdAA) and by immobilization of galactonic acid through a hydrophilic "spacer arm" molecule (PES-pdAA-SA-GAL). The modification steps were characterised by high resolution X-ray photoelectron spectroscopy. The performance of modified and unmodified membranes was evaluated by assessing the expression of liver specific biotransformation functions of pig and human hepatocytes. Human liver cells cultured on PES-pdAA-SA-GAL membranes displayed an enhanced albumin production, urea synthesis and protein secretion for 24 days of culture. The immobilisation of galactose derivative units on the membrane allowed specific interactions with hepatocytes biomimicking the cellular microenvironment and produced an improvement of the long-term maintenance and differentiation of human hepatocytes.     

Microwave-Assisted Extraction of Secoisolariciresinol Diglucoside��Method Development

An optimized microwave-assisted extraction (MAE) method was developed for extracting secoisolariciresinol diglucoside (SDG) from flaxseed. This paper presents the optimization of factors for maximizing the extraction yield of SDG. This work was conducted using the experimental domain identified in a previous study by means of screening designs, that is, samples of 1 g defatted flaxseed meal (DFM) were extracted with 50 ml NaOH of concentration of 0.5–1 M, at microwave power levels of 60–360 W, for 3–9 min, with the microwave power applied intermittently (power on 30 s/min) and continuously (power on 60 s/min). The MAE of SDG was maximized when 1 g DFM was extracted with 50 ml 0.5 M NaOH, at 135 W, for 3 min in intermittent power mode (power on 30 s/min). The optimized MAE achieved a 6% increase in the extraction yield (21.45 mg SDG per gram DFM) as opposed to a direct hydrolysis method (20.22 mg SDG per gram DFM). The MAE of SDG was governed by the microwave–NaOH interaction, which had a curvilinear dependence on the microwave power level, and linear dependence on the NaOH concentration. The microwave-induced effects accounted for a 10% increase in the SDG extraction yield (21.45 mg SDG per gram DFM) as opposed to a microwaveless control method (19.45 mg SDG per gram DFM). The optimized MAE method has good repeatability, a 97% recovery of the target compound; it is fast and efficient and can be used for precise quantification of SDG in flaxseed.     

The perception of risks associated with food-related hazards and the perceived reliability of sources of information

This study aimed to explore, on the one hand, public perception of risks associated with different food‐related hazards and, on the other hand, perception of reliability of various sources providing information on food‐related risks. Some differences were found when consumers compared six food‐related hazards in terms of perceived personal risk and their knowledge of potential food risks. The concern about food risks was found to be statistically significantly dependent on the perception of risk to the individual. As far as the perception of the reliability of information was concerned, a principal component analysis revealed some differences in terms of respondents’ perception when the sources were compared. Furthermore, a regression analysis showed that the perceived amount of information each source contained about food‐related hazards was an important element in perception of reliability, as well as the degree of concern consumers believed the agencies had with protecting their health from food risks.