Emerging contaminants are suspected to cause adverse effects in humans and wildlife. Aquatic ecosystems are continuously contaminated by agricultural and industrial sources. To establish a causality relationship between the occurrence of contaminants in the environment and disease, experiments including all environmental matrices must be performed. Consequently, the current analytical tools must be improved. A new multi-residue method for analysing 15 emerging pollutants in sediments based on the Quick, Easy, Cheap, Effective, Rugged and Safe approach is reported. The development of such a multirisque, inter-family method for sediment including pharmaceuticals, pesticides, personal care products and plasticizers is reported for the first time. The procedure involves salting-out liquid-liquid extraction using acetonitrile and clean-up with dispersive solid phase extraction, followed by liquid chromatography coupled with tandem mass spectrometry. The validated analytical procedure exhibited recoveries between 40 and 98% for every target compound. This methodology facilitated the determination of pollutant contents at nanogram-per-gram concentrations.

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Naturalists have been fascinated for centuries by animal colors and color patterns. While widely studied at the adult stage, we know little about color patterns in the embryo. Here, we study a trait consisting of coloration that is specific to the embryo and absent from postembryonic stages in water striders (Gerromorpha). By combining developmental genetics with chemical and phylogenetic analyses across a broad sample of species, we uncovered the mechanisms underlying the emergence and diversification of embryonic colors in this group of insects. We show that the pteridine biosynthesis pathway, which ancestrally produces red pigment in the eyes, has been recruited during embryogenesis in various extraocular tissues including antennae and legs. In addition, we discovered that this cooption is common to all water striders and initially resulted in the production of yellow extraocular color. Subsequently, 6 lineages evolved bright red color and 2 lineages lost the color independently. Despite the high diversity in colors and color patterns, we show that the underlying biosynthesis pathway remained stable throughout the 200 million years of Gerromorpha evolutionary time. Finally, we identified erythropterin and xanthopterin as the pigments responsible for these colors in the embryo of various species. These findings demonstrate how traits can emerge through the activation of a biosynthesis pathway in new developmental contexts.

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Giant lipid vesicles resemble compartments of biological cells, mimicking them in their dimension, membrane structure and partly in their membrane composition. The spontanenous appearance of closed membranes composed of bilayers of self-assembling amphiphiles was likely a prerequisite for Darwinian competitive behavior to set in at the molecular level. Such compartments should be dynamic in their membrane composition (evolvable), and sufficiently stable to harbor macromolecules (leak-free), yet semi-permeable for reactive small molecules to get across the membrane (stay away from chemical equilibrium). Here we describe bottom-up experiments simulating prebiotic environments that support the formation of simple amphiphilic molecules capable of self-assembling into vesicular objects on the micrometer scale. Long-chain alkyl phosphates, together with related amphiphilic compounds, were formed under simulated prebiotic phosphorylation conditions by using cyanamide, a recognized prebiotic chemical activator and a precursor for several compound classes. Crude dry material of the thus obtained prebiotic mixtures formed multilamellar giant vesicles once rehydrated at the appropriate pH and in the presence of plausibly prebiotic co-surfactants, as observed by optical microscopy. The size and the shape of lipid aggregates tentatively suggest that prebiotic lipid assemblies could encapsulate peptides or nucleic acids that could be formed under similar chemical prebiotic conditions. The formation of prebiotic amphiphiles was monitored by using TLC, IR, NMR and ESI-MS and UPLC-HRMS. In addition we provide a spectroscopic analysis of cyanamide under simulated prebiotic conditions in the presence of phosphate sources and spectroscopic analysis of O-phosphorylethanolamine as a plausible precursor for phosphoethanolamine lipids.

A total of 18 vacuum gas oils have been analyzed by Fourier transform ion cyclotron resonance mass spectrometry considering six replicates in three different ionization modes (electrospray ionization (ESI)(+), ESI(−), and atmospheric pressure photoionization (APPI)(+)) to characterize the nitrogen and sulfur compounds contained in these samples. Classical data analysis has been first performed on generated data sets using double bond equivalents (DBE) versus number of carbon atoms (#C) plots in order to observe similarities and differences within the nitrogen and sulfur-containing molecular classes from samples produced by different industrial processes. In a second step, three-way arrays have been generated for each ionization mode considering three dimensions: DBE related to aromaticity, number of carbon atoms related to alkylation, and sample. These threeway arrays have then be concatenated using low-level data fusion strategy to obtain a new tensor with three new modes: aromaticity, alkylation, and sample. The PARAFAC method has then been applied for the first time to this three-way data structure. A two components decomposition has allowed us to highlight unique samples with unexpected reactivity behaviors throughout hydrotreatment. The obtained loadings led to the identification of the variables responsible for this specific character. This original strategy has provided a fast visualization tool able to highlight simultaneously the impact of the three ionization modes in order to explain the differences between the samples and compare them.

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The flavonoid myricitrin-5-methyl ether is a potential drug candidate as a gastric lipase inhibitor for the treatment of obesity.