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Literature reports that ingestion of phytosterols and γ-oryzanol contributes to cholesterol lowering. Despite in vivo observations, thermodynamic phase equilibria could explain phenomena occurring during digestion leading to such effects. To advance the observations made by previous literature, this study was aimed at describing the complete solid-liquid phase equilibrium diagrams of cholesterol + phytosterol and γ-oryzanol systems by DSC, evaluating them by powder X-ray, microscopy, and thermodynamic modeling. Additionally, this study evaluated the phenomena observed by an in vitro digestibility method. Results confirmed the formation of solid solution in the cholesterol + phytosterols system at any concentration and that cholesterol + γ-oryzanol mixtures formed stable liquid crystalline phases with a significant melting temperature depression. The in vitro protocol supported the idea that the same phenomena can occur during digestion in which mechanochemical forces were probably the mechanisms promoting cholesterol solid phase changes in the presence of such phytocompounds. In this case, these changes could alter cholesterol solubility and possibly its absorption in the gastrointestinal lumen.

Amongst different climatic and anthropogenic drivers, water resources management can cause massive changes to the natural regime of a lake after its regulation, thereby affecting the quantity and quality of water intended for satisfying the multiple basin water requirements. Here, we investigate the multi-decadal variation of the water levels and outflows of Lake Garda, the largest in Italy, where the dam operational rules and the related basin water needs heavily altered the annual and seasonal trend of the lake regime since its regulation in 1951. Daily lake levels and outflows were first collected and digitized for the period 1888-2020, thus providing a unique database of 133 years that allowed a consistent comparison between natural and regulated periods. Statistical analyses highlighted a significant change of the inter-annual trend of the lake outflows, which passed from upward to downward after regulation, against a constant increasing trend of the water levels. Conversely, water levels showed a more remarkable shifts on a seasonal scale if compared to the outflows, revealing the influence of summer and winter basin water needs. Additional analyses on the inter-annual variation of the main downstream water demands regulated by the dam, i.e. the irrigation, hydropower and fluvial ecosystem requirements, outlined their relevance in changing the lake regime, influencing dam operational policies, which progressively limited the share of water released for ecosystem integrity. A comparison between the lake levels and outflows recorded for the pre-regulation and post-regulation periods of some selected European perialpine lakes finally highlighted different effects on the lake regime, drawing attention to the importance of defining the role of the dam operational policies within the current scenario of climate change and changing water demands., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Despite Federal Bureau of Investigation Laboratory announcing the discontinuation of bullet lead examinations, knowledge of the composition of the bullets has been used as an alternative means of identifying their origin, achieving success in some case studies. In this work, wavelength dispersion X-ray fluorescence (WDXRF) and chemometrics were used for the analysis of rifle bullets, in order to identify the spectral similarities of these samples. For this purpose, 54 lead core fragments from 7.62 mm rifle bullets from 5 different manufacturers were obtained: Companhia Brasileira de Cartuchos (CBC), Israel Military Industries (IMI), Federal Cartridge (FC), Fray Luiz Beltrán (FLB) and Zavod Vlasim (ZV). Principal components analysis (PCA) discriminated the five groups of bullets according to their manufacturers in a three-dimensional scores graph, where 3 principal components accounted for>99% of the variability between the samples. The spectral region for Sb and the scattering region together proved to be determinant for discrimination of the groups. The dendrogram presented in the hierarchical cluster analysis (HCA) showed the formation of five groups. The k-nearest neighbor algorithm (k-NN) and soft independent modeling of class analogy (SIMCA) correctly classified all samples of the test set. X-ray scattering spectrum were used for the first time in the analysis of the fragments and contributed to the grouping of samples from the same manufacturers. The results indicate that the WDXRF technique is suitable for forensic purposes in case studies, as, besides being quick and relatively simple, it has the advantage of preserving evidence., Competing Interests: Conflict of interest The authors declare that they have no conflict of interest., (Copyright © 2021 Elsevier B.V. All rights reserved.)

During the last decennium, it has become widely accepted that ubiquitous bacterial viruses, or bacteriophages, exert enormous influences on our planet's biosphere, killing between 4-50% of the daily produced bacteria and constituting the largest genetic diversity pool on our planet. Currently, bacterial infections linked to healthcare services are widespread, which, when associated with the increasing surge of antibiotic-resistant microorganisms, play a major role in patient morbidity and mortality. In this scenario, Pseudomonas aeruginosa alone is responsible for ca. 13-15% of all hospital-acquired infections. The pathogen P. aeruginosa is an opportunistic one, being endowed with metabolic versatility and high (both intrinsic and acquired) resistance to antibiotics. Bacteriophages (or phages) have been recognized as a tool with high potential for the detection of bacterial infections since these metabolically inert entities specifically attach to, and lyse, bacterial host cells, thus, allowing confirmation of the presence of viable cells. In the research effort described herein, three different phages with broad lytic spectrum capable of infecting P. aeruginosa were isolated from environmental sources. The isolated phages were elected on the basis of their ability to form clear and distinctive plaques, which is a hallmark characteristic of virulent phages. Next, their structural and functional stabilization was achieved via entrapment within the matrix of porous alginate, biopolymeric, and bio-reactive, chromogenic hydrogels aiming at their use as sensitive matrices producing both color changes and/or light emissions evolving from a reaction with (released) cytoplasmic moieties, as a bio-detection kit for P. aeruginosa cells. Full physicochemical and biological characterization of the isolated bacteriophages was the subject of a previous research paper.

Aim: A sodium alginate-based biohydrogel was prepared integrating choline oleate deep euthetic solvent as facilitator of transdermal delivery and a cocktail of lytic bacteriophages for Acinetobacter baumannii , aiming at treating soft-tissue infections by the aforementioned pathogen. Materials & methods: Two bacteriophages were isolated from a hospital sewage and a wastewater treatment plant sewage in Sorocaba (Brazil), and characterized via SDS-PAGE electrophoresis, transmission electron microscope and evaluation of lytic spectra of the bacteriophage cocktail. The biohydrogel was prepared and characterized by DSC, FTIR, XRD, DESEM, XRT and transdermal permeation of the bacteriophage cocktail. Results & conclusion: The physico-chemical characterization of the biohydrogel produce indicated adequate structural characteristics and ability to promote/facilitate transdermal delivery of bacteriophage particles, thus showing potential for biopharmaceutical applications.

In this research project, synthesis and characterization of ionic liquids and their subsequent utilization as facilitators of transdermal delivery of human insulin was pursued. Choline geranate and choline oleate ionic liquids (and their deep eutectic solvents) were produced and characterized by nuclear magnetic resonance ( 1 H NMR), water content, oxidative stability, cytotoxicity and genotoxicity assays, and ability to promote transdermal protein permeation. The results gathered clearly suggest that all ionic liquids were able to promote/facilitate transdermal permeation of insulin, although to various extents. In particular, choline geranate 1:2 combined with its virtually nil cyto- and geno-toxicity was chosen to be incorporated in a biopolymeric formulation making it a suitable facilitator aiming at transdermal delivery of insulin., (Copyright © 2020 Jorge, Harada, Silva, Campos, Moreli, Shimamoto, Pereira, Oliveira, Tubino, Vila and Balcão.)

Some lipidic bioactives are largely reported to present hypocholesterolemic effects, for example, oleic acid, α-tocopherol, and octacosanol, found in rice-bran, olive, and sunflower oils. In contrast, some saturated and trans-unsaturated lipids found in animal fats or partially hydrogenated oils have been associated with the opposite effect. However, the mechanisms in which these lipids act for lowering or increasing cholesterol are not fully understood. In this context, this work was aimed at a fundamental physicochemical comprehension of how cholesterol phase behavior is affected in mixtures with these compounds. The complete solid-liquid equilibrium (SLE) phase diagrams of these mixtures were depicted by differential scanning calorimetry and microscopy, and also evaluated by the SLE thermodynamic theory. The minimal melting temperature (eutectic points) of the mixtures followed the order: α-tocopherol < oleic acid < elaidic acid < stearic acid < octacosanol. Among all biocompounds, stearic and trans-oleic acids promoted few changes in the normal thermodynamic behavior of cholesterol when in a mixture. In contrast, α-tocopherol induced a significant temperature depression in the system. Furthermore, at high concentrations of cholesterol (>90% molar fraction), the formation of solid solution was observed in all other systems, to a higher degree for oleic acid. The higher interactions of these beneficial compounds and the formation of solid solution that literature associates with the alteration of cholesterol enteric absorption probably correlates with their hypocholesterolemic effects.

A simple and selective spectrophotometric method has been developed for the first time for the determination of sodium methoxide in methanol solution in the presence of sodium hydroxide. The developed method involves the formation of a pink species by the reaction between sodium methoxide and α-santonin. The pink compound formed shows absorbance maximum at 513 nm. N, N-Dimethylformamide and methanol were used as solvents, and the reaction was performed at different temperatures and 25 °C was selected for further experiments. The pink compound formed was dried and then was studied using FTIR and mass spectrometry. The calibration curve was constructed from 0.10 to 0.30% (m/v) sodium methoxide in methanol, and the standard deviation is 0.010%. Similarly, the relative standard deviations of 28%, 26%, and 24% solutions of sodium methoxide were obtained in the range of 0.4 to 1.9%. The correlation coefficient of the analytical curve r = 0.9997; the limit of detection, LOD, is ca. 1.1 × 10 -3 % w/w; and the limit of quantification, LOQ, is ca. 3.2 × 10 -3 % w/w. The results of analysis were validated statistically.

Biodiesel quality is checked by determining several parameters. Considering the large number of analyses in this verification, as well as the disadvantages of the use of toxic solvents and waste generation, multivariate calibration is suggested to reduce the number of tests. In this work, hydrogen nuclear magnetic resonance ( 1 H NMR) spectra were used to build multivariate models, from partial least squares (PLS), in order to perform simultaneous determination of six important quality parameters of biodiesel: density at 20°C, kinematic viscosity at 40°C, iodine value, acid number, oxidative stability, and water content. 1 H NMR spectrum reflects the structures of the compounds present in biodiesel and showed suitable correlations with the six parameters. In addition, the models were appropriate to predict all parameters for external samples. Thus, the alliance between 1 H NMR spectra and PLS was shown to be applicable to extract a lot of information about biodiesel quality, significantly reducing analysis time, reagent and solvent consumption, and waste generation., (Copyright © 2017 Elsevier B.V. All rights reserved.)