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Excessive use of plastics in daily life and the inappropriate disposal of plastic products are severely affecting wildlife species in both coastal and aquatic environments. Birds are top-predators, exposed to all threats affecting their environments, making them ideal sentinel organisms for monitoring ecosystems change. We set a baseline assessment of the prevalence of marine plastic litter affecting multi-species populations of aquatic birds in southern Portugal. By examining 160 stomach contents from 8 species of aquatic birds, we show that 22.5% were affected by plastic debris. Plastic was found in Ciconia ciconia , Larus fuscus and L. michahellis . Ciconia ciconia ingested the highest amount (number of items and total mass) of plastic debris. Polydimethylsiloxane (PDMS, silicones) was the most abundant polymer and was recorded only in C. ciconia . Plastic ingestion baseline data are of crucial importance to evaluate changes through time and among regions and to define management and conservation strategies. [ABSTRACT FROM AUTHOR]

Abstract: The solvatochromic parameters characterizing the solvent dipolarity/polarizability (π*), solvent hydrogen-bond donor acidity (α), and solvent hydrogen-bond acceptor basicity (β) of aqueous media were measured in the coexisting phases of aqueous Dextran-Ficoll, Dextran-Ucon, Dextran-PEG, PEG-Ucon, Ficoll-Ucon, and Ficoll-PEG two-phase systems (ATPS). Ionic composition of each ATPS included 0.15M KCl, 0.15M KBr, 0.15M NaBr, 0.1M Na2SO4, and 0.1M Li2SO4 in 0.01M sodium phosphate buffer (NaPB), pH 7.4; and 0.01M and 0.11M sodium phosphate buffer, pH 7.4. Partition ratios of sodium salts of dinitrophenylated (DNP) amino acids with aliphatic side-chains (glycine, alanine, norvaline, norleucine, and α-amino-n-caprylic acid) were measured in all ATPSs, and the results were evaluated in terms of the differences between the relative hydrophobicity (parameter E) and the electrostatic properties (parameter C) of the aqueous media of the coexisting phases. It was established that parameter E is described by a linear combination of the differences between the solvent dipolarity/polarizability (Δπ*) and between the solvent hydrogen-bond acidity (Δα) of the media in the coexisting phases. Parameter C depends on the phase forming polymer pair and is shown to be described by a linear combination of three parameters: the differences between the solvent hydrogen-bond acidity (Δα) and between the solvent hydrogen-bond basicity (Δβ) of the media in the coexisting phases, and a measure of the effect of a given salt additive on the hydrogen bonds in water. This effect was represented by a parameter (K b−l ), characterizing the equilibrium between populations of hydrogen bonds with a bent hydrogen bond conformation and with linear hydrogen bond conformation affected by a given salt additive. [Copyright &y& Elsevier]

Abstract: Distribution coefficients for a variety of proteins and certain other biomolecules (peptides, amino acids, and carbohydrates) (overall 27 different solutes) were measured in aqueous two-phase systems (ATPSs) dextran (Dex)–polyethylene glycol (PEG) and Dex–Ucon 50-HB-5100 (Ucon—a random copolymer of ethylene glycol and propylene glycol) both containing 0.15M NaCl in 0.01M phosphate buffer, pH 7.4, at 23°C. Distribution coefficients of some selected solutes were also measured in the above two-phase systems at three different polymer concentrations for each system. It was established that the distribution coefficients for all the proteins examined in the ATPSs are correlated according to the so-called Collander linear equation. [Copyright &y& Elsevier]

In this work the modified Wilson equation, proposed in a previous publication, for aqueous binary polymer solutions is extended to calculate liquid–liquid equilibrium of aqueous two-phase systems containing one salt with either polyethylene glycol or ethylene oxide–propylene oxide random copolymer. The Debye–Hu¨ckel equation based on the Fowler–Guggenheim theory is used to represent the long-range electrostatic interactions of ions. The parameters are estimated from only one or two tie-lines and are used to predict the phase diagrams with different molecular weights and polymer–salt systems at different temperatures. The predictions obtained with the modified Wilson equation are in good agreement with the experimental data. [Copyright &y& Elsevier]

A local composition model based on the lattice theory and two-fluid theory, considering the excess heat capacity, which is a modified Wilson equation, is developed for the excess Gibbs energy of aqueous polymer solutions. The model represents a synergistic combination of the excess entropy for mixing molecules of different sizes and the temperature dependent residual contribution, which combines the attractive interactions between solvent molecules and the segments with the contribution of the excess heat capacity. The results of the extrapolation with respect to molecular weight of phase equilibrium in aqueous polymer solutions with this model are very satisfactory, with only two adjustable parameters. [Copyright &y& Elsevier]

• Erwinia chrysanthemi (ErA II) L-asparaginase was stabilized by osmolytes. • Sucrose and sorbitol were protecting/compatible solutes to ErA II. • Some excipients avoided the formation of high molecular weight aggregates of ErA II. L-asparaginase is used for the treatment of acute lymphoblastic leukaemia (ALL); however, its formulation presents drawbacks such as a lack of stability and formation of aggregates. Osmolytes are small molecules accumulated by cells in response to environmental stresses and present a protective behaviour, favouring the equilibrium of macromolecules towards the native conformation. Therefore, osmolytes are employed as excipients in pharmaceutical protein formulations. Herein, recombinant L-ASNase II from Erwinia chrysanthemi (ErA II) was analysed with respect to the effect of osmolytes on kinetic and stability of this biopharmaceutical. The aggregation profiles were analysed trough nanotracking particle analysis and dynamic light scattering. The majority of the tested osmolytes increased ErA II specific activity and stability, being more pronounced for sucrose and sorbitol, which increased almost 70% of ErA II activity. The polyol preserved total enzyme activity for 30 days while sucrose preserved 81.1 ± 5.3% total enzyme activity over this period. Each osmolyte resulted in a specific aggregation profile and the presence of sucrose or sorbitol resulted in a lower quantity of aggregates in the range of 100–300 nm. The present findings may contribute to the improvement of adjuvants in L-ASNase formulations and the optimization of other biopharmaceutical formulations. [ABSTRACT FROM AUTHOR]