Influence of pumpkin seed oil in continuous phase on droplet size and stability of water-in-oil emulsions

The aim of this work was to contribute to the optimized production of water-in-oil emulsions with pumpkin seed oil in the oil phase using a high-speed homogenizer. Pumpkin seed oil is a valuable natural source of essential fatty acids and biologically active micronutrients that contribute to its nutritive value and medical uses, and reduce interfacial tension between water and the oil phases. Therefore, pumpkin seed oil can be considered as a prosperous oil phase whose use can possibly decrease the amount of some emulsifier that is normally involved in every emulsification process. A central composite rotatable experimental design was implemented to analyze the impact of the contents of polyglycerol polyricinoleate and pumpkin seed oil in the continuous phase, as well as water phase content in the emulsion on droplet size distribution and the response surface methodology was used to obtain optimal conditions for water-in-oil emulsion preparation. Mean size diameter of water droplets was in a range from 400 to 850 nm, with mean peak width of 100 to 220 nm, respectively. The influence of all three investigated factors on the emulsification was determined. Additionally, the emulsions prepared with pumpkin seed oil showed a higher stability during the storage time compared to the emulsions with sunflower oil

Challenging assumptions of the enlargement literature : the impact of the EU on human and minority rights in Macedonia

This article argues that from the very start of the transition process in Macedonia, a fusion of concerns about security and democratisation locked local nationalist elites and international organisations intoa political dynamic that prioritised security over democratisation. This dynamic resulted in little progress in the implementation of human and minority rights until 2009, despite heavy EU involvement in Macedonia after the internal warfare of 2001. The effects of this informally institutionalised relationship have been overlooked by scholarship on EU enlargement towards Eastern Europe, which has made generalisations based on assumptions relevant to the democratisation of countries in Eastern Europe, but not the Western Balkans

Golgi-localized STELLO proteins regulate the assembly and trafficking of cellulose synthase complexes in Arabidopsis.

As the most abundant biopolymer on Earth, cellulose is a key structural component of the plant cell wall. Cellulose is produced at the plasma membrane by cellulose synthase (CesA) complexes (CSCs), which are assembled in the endomembrane system and trafficked to the plasma membrane. While several proteins that affect CesA activity have been identified, components that regulate CSC assembly and trafficking remain unknown. Here we show that STELLO1 and 2 are Golgi-localized proteins that can interact with CesAs and control cellulose quantity. In the absence of STELLO function, the spatial distribution within the Golgi, secretion and activity of the CSCs are impaired indicating a central role of the STELLO proteins in CSC assembly. Point mutations in the predicted catalytic domains of the STELLO proteins indicate that they are glycosyltransferases facing the Golgi lumen. Hence, we have uncovered proteins that regulate CSC assembly in the plant Golgi apparatus.The work presented in this paper was supported by grants from the BBSRC: BB/G016240/1 BBSRC Sustainable Energy Centre Cell Wall Sugars Programme (BSBEC) and the European Community’s Seventh Framework Programme SUNLIBB (FP7/2007-2013) under the grant agreement n° 251132 to PD. The UK 850 MHz solid-state NMR Facility was funded by EPSRC and BBSRC, as well as the University of Warwick including via part funding through Birmingham Science City Advanced Materials Projects 1 and 2 supported by Advantage West Midlands (AWM) and the European Regional Development Fund (ERDF); we thank Dinu Iuga for experimental assistance, and Chris Somerville for helpful discussions and suggesting the name STELLO. The authors acknowledge LNBio and LNLS for providing X-ray beam time (proposal GAR 15208), and the Sainsbury Laboratory Cambridge University for imaging facilities. TV was supported by an EMBO long-term fellowship (ALTF 711-2012) and by postdoctoral funding from the Philomathia Foundation. HEM was supported by an EMBO Long Term Fellowship (ALTF-1246-2013) and an NSERC Postdoctoral Fellowship (PDF-454454-2014). SP and YZ were supported by the Max-Planck Gesellschaft, and SP was also supported by a R@MAP Professor position at UoM. We thank the Biological Optical Microscopy Platform (BOMP) at University of Melbourne, and Tom Simmons and Rita Marques for assistance on sugar analyses.This is the final version of the article. It first appeared from Nature Publishing Group via http://dx.doi.org/10.1038/ncomms11656

Two Tryptophans Are Better Than One in Accelerating Electron Flow through a Protein

We have constructed and structurally characterized a <i>Pseudomonas aeruginosa</i> azurin mutant <b>Re126WWCu^I</b>, where two adjacent tryptophan residues (W124 and W122, indole separation 3.6–4.1 Å) are inserted between the Cu^I center and a Re photosensitizer coordinated to the imidazole of H126 (Re^I(H126)­(CO)₃(4,7-dimethyl-1,10-phenanthroline)⁺). Cu^I oxidation by the photoexcited Re label (*Re) 22.9 Å away proceeds with a ∼70 ns time constant, similar to that of a single-tryptophan mutant (∼40 ns) with a 19.4 Å Re–Cu distance. Time-resolved spectroscopy (luminescence, visible and IR absorption) revealed two rapid reversible electron transfer steps, W124 → *Re (400–475 ps, <i>K</i>₁ ≅ 3.5–4) and W122 → W124^•+ (7–9 ns, <i>K</i>₂ ≅ 0.55–0.75), followed by a rate-determining (70–90 ns) Cu^I oxidation by W122^•+ ca. 11 Å away. The photocycle is completed by 120 μs recombination. No photochemical Cu^I oxidation was observed in <b>Re126FWCu^I</b>, whereas in <b>Re126WFCu^I</b>, the photocycle is restricted to the ReH126W124 unit and Cu^I remains isolated. QM/MM/MD simulations of <b>Re126WWCu^I</b> indicate that indole solvation changes through the hopping process and W124 → *Re electron transfer is accompanied by water fluctuations that tighten W124 solvation. Our finding that multistep tunneling (hopping) confers a ∼9000-fold advantage over single-step tunneling in the double-tryptophan protein supports the proposal that hole-hopping through tryptophan/tyrosine chains protects enzymes from oxidative damage

Tryptophan-Accelerated Electron Flow Across a Protein−Protein Interface

We report a new metallolabeled blue copper protein, Re126W122Cu^I Pseudomonas aeruginosa azurin, which has three redox sites at well-defined distances in the protein fold: Re^I(CO)_3(4,7-dimethyl-1,10-phenanthroline) covalently bound at H126, a Cu center, and an indole side chain W122 situated between the Re and Cu sites (Re-W122(indole) = 13.1 Å, dmp-W122(indole) = 10.0 Å, Re-Cu = 25.6 Å). Near-UV excitation of the Re chromophore leads to prompt Cu^I oxidation (<50 ns), followed by slow back ET to regenerate Cu^I and ground-state Re^I with biexponential kinetics, 220 ns and 6 μs. From spectroscopic measurements of kinetics and relative ET yields at different concentrations, it is likely that the photoinduced ET reactions occur in protein dimers, (Re126W122CuI)2 and that the forward ET is accelerated by intermolecular electron hopping through the interfacial tryptophan: ^*Re//←W122←Cu^I, where // denotes a protein–protein interface. Solution mass spectrometry confirms a broad oligomer distribution with prevalent monomers and dimers, and the crystal structure of the Cu^(II) form shows two Re126W122Cu^(II) molecules oriented such that redox cofactors Re(dmp) and W122-indole on different protein molecules are located at the interface at much shorter intermolecular distances (Re-W122(indole) = 6.9 Å, dmp-W122(indole) = 3.5 Å, and Re-Cu = 14.0 Å) than within single protein folds. Whereas forward ET is accelerated by hopping through W122, BET is retarded by a space jump at the interface that lacks specific interactions or water molecules. These findings on interfacial electron hopping in (Re126W122Cu^I)^2 shed new light on optimal redox-unit placements required for functional long-range charge separation in protein complexes

Pets as Sentinels of Human Exposure to Neurotoxic Metals

The idea that animals may be used as sentinels of environmental hazards pending over humans and the associated public health implications is not a new one. Nowadays pets are being used as bioindicators for the effects of environmental contaminants in human populations. This is of paramount importance due to the large increase in the worldwide distribution of synthetic chemicals, particularly in the built environment. Companion animals share the habitat with humans being simultaneously exposed to and suffering the same disease spectrum as their masters. Moreover, their shorter latency periods (due to briefer lifespans) enable them to act as early warning systems, allowing timely public health interventions. The rise on ethical constraints on the use of animals and, consequently, on the sampling they can be subjected to has led to the preferential use of noninvasive matrices, and in this case we are looking into hair. This chapter focuses in three non-essential metals: mercury, lead, and cadmium, due to their ubiquitous presence in the built environment and their ability of affecting the mammal nervous system. There is a fairly short amount of studies reporting the concentrations of these metals in pets’ hair, particularly for cats. These studies are characterized, and the metal concentrations corresponding to different parameters (e.g., age, sex, diet, rearing) are described in order to provide the reader with a general vision on the use of this noninvasive matrix on the studies conducted since the last two decades of the twentieth century.publishe