The production of bromophenols resulting from the chlorination of waters containing bromide ion and phenol

The formation of 2,4,6-tribromophenol is shown to result from the chlorination of water containing phenol and bromide ion at pH 7.4. Direct bromination with hypobromous acid is compared with bromination by hypochlorous acid and bromide ion. Under conditions where HOCl is not limiting, a higher yield of bromine substitution products can be expected from bromination by HOCl + Br⁻ than by direct bromination by HOBr.     

Azobenzene-containing linear–dendritic block copolymers prepared by sequential ATRP and click chemistry

A series of light responsive linear–dendritic BCs consisting of a liquid crystalline aliphatic polyester dendron functionalized with sixteen 4-cyanoazobenzene moieties linked to a linear block of poly(methyl methacrylate), poly(ethyl methacrylate) or poly(styrene) have been investigated. The linear block was synthesis by atom transfer radical polymerization using an alkyne terminated initiator and was coupled to dendron with an azido group at the focal point by a Huisgen's 1,3-dipolar cycloaddition. The effectiveness of the coupling reaction and purity of the block copolymers was asserted by chromatographic and spectroscopic techniques as well as their thermal behaviour was studied by thermogravimetric analysis, differential scanning calorimetry and optical microscopy. Morphology, optical properties and photoinduced response of these block copolymers have also been evaluated.     

Quality of goat′s milk cheese as affected by coating with edible chitosan‐essential oil films

The effectiveness of applying chitosan coatings containing rosemary and oregano essential oils to cheeses was analysed. Cheeses were coated by immersing the samples two or three times successively in the different formulations. The ripening indexes, water loss, fungal growth and sensory properties of the coated and noncoated cheeses throughout ripening were evaluated. The coatings both prevented weight loss and improved the microbial safety. The lipolytic and proteolytic activities were reduced in coated cheese, which is in line with the antimicrobial effect of active coatings. Sensory evaluation revealed that the cheeses double‐coated with chitosan–oregano oil were the best evaluated in terms of aroma and flavour.     

Lipidomics Reveals Cisplatin-Induced Renal Lipid Alterations during Acute Kidney Injury and Their Attenuation by Cilastatin

Nephrotoxicity is a major complication of cisplatin-based chemotherapy, leading to acute kidney injury in ca. 30% of patients, with no preventive intervention or treatment available for clinical use. Cilastatin has proved to exert a nephroprotective effect for cisplatin therapies in in vitro and in vivo models, having recently entered clinical trials. A deeper understanding at the molecular level of cisplatin-induced renal damage and the effect of potential protective agents could be key to develop successful nephroprotective therapies and to establish new biomarkers of renal damage and nephroprotection. A targeted lipidomics approach, using LC-MS/MS, was employed for the quantification of 108 lipid species (comprising phospholipids, sphingolipids, and free and esterified cholesterol) in kidney cortex and medulla extracts from rats treated with cisplatin and/or cilastatin. Up to 56 and 63 lipid species were found to be altered in the cortex and medulla, respectively, after cisplatin treatment. Co-treatment with cilastatin attenuated many of these lipid changes, either totally or partially with respect to control levels. Multivariate analysis revealed that lipid species can be used to discriminate renal damage and nephroprotection, with cholesterol esters being the most discriminating species, along with sulfatides and phospholipids. Potential diagnostic biomarkers of cisplatin-induced renal damage and cilastatin nephroprotection were also found.     

Stereoselective hydride transfer by aryl-alcohol oxidase, a member of the GMC superfamily

Primary alcohol oxidation by aryl‐alcohol oxidase (AAO), a flavoenzyme providing H₂O₂ to ligninolytic peroxidases, is produced by concerted proton and hydride transfers, as shown by substrate and solvent kinetic isotope effects (KIEs). Interestingly, when the reaction was investigated with synthesized (R)‐ and (S)‐α‐deuterated p‐methoxybenzyl alcohol, a primary KIE (≈6) was observed only for the R enantiomer, revealing that the hydride transfer is highly stereoselective. Docking of p‐methoxybenzyl alcohol at the buried crystal active site, together with QM/MM calculations, showed that this stereoselectivity is due to the position of the hydride‐ and proton‐receiving atoms (flavin N5 and His502 Nε, respectively) relative to the alcohol Cα‐substituents, and to the concerted nature of transfer (the pro‐S orientation corresponding to a 6 kcal mol^?1 penalty with respect to the pro‐R orientation). The role of His502 is supported by the lower activity (by three orders of magnitude) of the H502A variant. The above stereoselectivity was also observed, although activities were much lower, in AAO reactions with secondary aryl alcohols (over 98 % excess of the R enantiomer after treatment of racemic 1‐(p‐methoxyphenyl)ethanol, as shown by chiral HPLC) and especially with use of the F501A variant. This variant has an enlarged active site that allow better accommodation of the α‐substituents, resulting in higher stereoselectivity (S/R ratios) than is seen with AAO. High enantioselectivity in a member of the GMC oxidoreductase superfamily is reported for the first time, and shows the potential for engineering of AAO for deracemization purposes.     

Camera characterization for improving color archaeological documentation

Determining the correct color is essential for proper cultural heritage documentation and cataloging. However, the methodology used in most cases limits the results since it is based either on perceptual procedures or on the application of color profiles in digital processing software. The objective of this study is to establish a rigorous procedure, from the colorimetric point of view, for the characterization of cameras, following different polynomial models. Once the camera is characterized, users obtain output images in the sRGB space that is independent of the sensor of the camera. In this article we report on pyColorimetry software that was developed and tested taking into account the recommendations of the Commission Internationale de l'Éclairage (CIE). This software allows users to control the entire digital image processing and the colorimetric data workflow, including the rigorous processing of raw data. We applied the methodology on a picture targeting Levantine rock art motifs in Remigia Cave (Spain) that is considered part of a UNESCO World Heritage Site. Three polynomial models were tested for the transformation between color spaces. The outcomes obtained were satisfactory and promising, especially with RAW files. The best results were obtained with a second‐order polynomial model, achieving residuals below three CIELAB units. We highlight several factors that must be taken into account, such as the geometry of the shot and the light conditions, which are determining factors for the correct characterization of a digital camera.     

Variants of STAR,AMH and ZFPM2/FOG2 May Contribute towards the Broad Phenotype Observed in 46,XY DSD Patients with Heterozygous Variants of NR5A1

Variants of NR5A1 are often found in individuals with 46,XY disorders of sex development (DSD) and manifest with a very broad spectrum of clinical characteristics and variable sex hormone levels. Such complex phenotypic expression can be due to the inheritance of additional genetic hits in DSD-associated genes that modify sex determination, differentiation and organ function in patients with heterozygous NR5A1 variants. Here we describe the clinical, biochemical and genetic features of a series of seven patients harboring monoallelic variants in the NR5A1 gene. We tested the transactivation activity of novel NR5A1 variants. We additionally included six of these patients in a targeted diagnostic gene panel for DSD and identified a second genetic hit in known DSD-causing genes STAR, AMH and ZFPM2/FOG2 in three individuals. Our study increases the number of NR5A1 variants related to 46,XY DSD and supports the hypothesis that a digenic mode of inheritance may contribute towards the broad spectrum of phenotypes observed in individuals with a heterozygous NR5A1 variation.     

Sweet Wine Production by Two Osmotolerant Saccharomyces cerevisiae Strains

The use of Saccharomyces cerevisiae to produce sweet wine is difficult because yeast is affected by a hyperosmotic stress due to the high sugar concentrations in the fermenting must. One possible alternative could be the coimmobilization of the osmotolerant yeast strains S. cerevisiae X4 and X5 on Penicillium chrysogenum strain H3 (GRAS) for the partial fermentation of raisin musts. This immobilized has been, namely, as yeast biocapsules. Traditional sweet wine (that is, without fermentation of the must) and must partially fermented by free yeast cells were also used for comparison. Partially fermented sweet wines showed higher concentration of the volatile compounds than traditionally produced wines. The wines obtained by immobilized yeast cells reached minor concentrations of major alcohols than wines by free cells. The consumption of specific nitrogen compounds was dependent on yeast strain and the cellular immobilization. A principal component analysis shows that the compounds related to the response to osmotic stress (glycerol, acetaldehyde, acetoin, and butanediol) clearly differentiate the wines obtained with free yeasts but not the wines obtained with immobilized yeasts.