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Triacylglycerols, which are quasi-universal components of food matrices, consist of complex mixtures of molecules. Their site-specific C content, their fatty acid profile, and their position on the glycerol moiety may significantly vary with the geographical, botanical, or animal origin of the sample. Such variables are valuable tracers for food authentication issues. The main objective of this work was to develop a new method based on a rapid and precise C-NMR spectroscopy (using a polarization transfer technique) coupled with multivariate linear regression analyses in order to quantify the whole set of individual fatty acids within triacylglycerols. In this respect, olive oil samples were analyzed by means of both adiabatic C-INEPT sequence and gas chromatography (GC). For each fatty acid within the studied matrix and for squalene as well, a multivariate prediction model was constructed using the deconvoluted peak areas of C-INEPT spectra as predictors, and the data obtained by GC as response variables. This C-NMR-based strategy, tested on olive oil, could serve as an alternative to the gas chromatographic quantification of individual fatty acids in other matrices, while providing additional compositional and isotopic information. [ABSTRACT FROM AUTHOR]

After extraction of high-added value components of Spirulina sp., the remaining residues can be valorized by hydrothermal liquefaction to produce an oily water insoluble viscous phase (biocrude) which is very similar to petroleum bitumen. This hydrophobic fraction is composed of various N-,O-containing cyclic compounds, fatty acids, amides, nitriles, alkenes and alkanes. In order to optimize the rheological properties of the biocrude, we studied the addition of different catalysts with various loadings: ZrO 2 or CeO 2 , or Ce(NO 3) 3.6H 2 O as well as the effect of residence time during HTL. The biocrude has been systematically characterized by GCxGC, GPC, elemental analyses and dynamic shear rheology and compared to a petroleum bitumen. The different catalysts tested had little influence on the composition of the HTL hydrophobic fraction in the chosen operating conditions. In contrast, increasing the reaction time (from 1 to 7 h) was found to promote condensation reactions, thereby increasing the average molecular weight of the biocrude, leading to a viscoelastic material very similar to a petroleum bitumen. 1. Valorization of microalgae residues by catalytic HTL 2. Various catalytic system were compared (homogeneous and heterogeneous) 3. GPC, GCxGC-MS, elemental analysis were carried out on the biocrude 4. Bio-binder similar to petroleum one assessed by rheological characterization 5. Bio-bitumen rheology is strongly affected by the time of HTL [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study was to conceive a reactive transport model capable of providing quantitative site-specific enrichment factors for fractionation in 13C isotopic content during sorption. As test compound the model treats vanillin, for which the 13C isotopic content at natural abundance at each of the 8 carbon positions can be measured by quantitative 13C nuclear magnetic resonance spectrometry. This technique determines the isotope ratios with a resolution better than ±1‰ (0.1%) at each carbon position. Site-specific isotope fractionations were recorded in chromatography column experiments with silica RP-18 as stationary phase. The one dimensional reactive transport model accounted for the sorption/desorption behavior of 8 individual 13C-isotopomers and one 12C-isotopomer of vanillin and reproduced satisfactorily the bulk (average over the whole compound) fractionation observed during elution. After model calibration, the enrichment factors were fitted for each carbon site where a significant fractionation was recorded. To show the interest of such a transport model for environmental studies, the model, extended to three dimensions, was exploited to simulate reactive transport in an aquifer. These results show that significant 13C isotope fractionation is expected for 4 out of 8 13C-isotopomers in vanillin, and illustrate that bulk isotope ratios measured by conventional compound specific isotope analysis and mass spectrometry would hardly document significant isotope fractionations in vanillin. It is concluded that modeling of site-specific isotope ratios in molecules is a priori feasible and may help to quantify unknown processes in the environment. [Copyright &y& Elsevier]

This present study identifies a number of azolyl-substituted indoles as potent inhibitors of aromatase. In the sub-series of 3-(azolylmethyl)-1H-indoles, four imidazole derivatives and their triazole analogues were tested. Imidazole derivatives 11 and 14 in which the benzyl moiety was substituted by 2-chloro and 4-cyano groups, respectively, were the most active, with IC50 values ranging between 0.054 and 0.050 μM. In the other sub-series, eight 3-(α-azolylbenzyl)-1H-indoles were prepared and tested. Compound 30, the N-ethyl imidazole derivative, proved to be an aromatase inhibitor, showing an IC50 value of 0.052 μM. All target compounds were further evaluated against 17α-hydroxylase/C17,20-lyase to determine their selectivity profile. [ABSTRACT FROM AUTHOR]

The present study was designed to follow our pharma-comodulation work in the field of non-steroidal aromatase inhibitors. All target compounds 12a-h and 28a-h were tested in vitro for human placental aroma-tase inhibition, using testosterone or androstenedione the substrate for the aromatase enzyme and the IC30 and relative potency to aminoglutethimide data are included. A SAR study indicated that 3-[(4-fluorophenyl)(1 Himidazol-1-yl) methyl]-1-ethyl-2-methyl-1H-indole (28g) was a highly potent and selective aromatase inhibitor with IC50 value of 0.025 µM. 28 g was also a weak inhibitor of androstenedione synthesis. [ABSTRACT FROM AUTHOR]