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Berlin Brandenburg

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  • 1
    Language: English
    In: Science (New York, N.Y.), 08 August 2014, Vol.345(6197), pp.673-6
    Description: Anaerobic microbial degradation of hydrocarbons, typically occurring at the oil-water transition zone, influences the quality of oil reservoirs. In Pitch Lake, Trinidad and Tobago--the world's largest asphalt lake--we found that microorganisms are metabolically active in minuscule water droplets (1 to 3 microliters) entrapped in oil. Pyrotag sequencing of individual droplet microbiomes revealed complex methanogenic microbial communities actively degrading the oil into a diverse range of metabolites, as shown by nuclear magnetic resonance and Fourier transform ion cyclotron resonance mass spectrometry. High salinity and water-stable isotopes of the droplets indicate a deep subsurface origin. The 13.5% water content and the large surface area of the droplets represent an underestimated potential for biodegradation of oil away from the oil-water transition zone.
    Keywords: Water Microbiology ; Archaea -- Metabolism ; Bacteria -- Metabolism ; Lakes -- Microbiology ; Microbiota -- Genetics ; Petroleum -- Metabolism
    ISSN: 00368075
    E-ISSN: 1095-9203
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  • 2
    Language: English
    In: ChemInform, May 2016, Vol.47(23), pp.no-no
    Description: Review: 56 refs.
    Keywords: Analytical Chemistry ; Review ; Magnetic Resonance ; Nuclear Quadrupole Resonance Organic Substances
    ISSN: 0931-7597
    E-ISSN: 1522-2667
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  • 3
    Language: English
    In: Proceedings of the National Academy of Sciences of the United States of America, 16 February 2010, Vol.107(7), pp.2763-8
    Description: Numerous descriptions of organic molecules present in the Murchison meteorite have improved our understanding of the early interstellar chemistry that operated at or just before the birth of our solar system. However, all molecular analyses were so far targeted toward selected classes of compounds with a particular emphasis on biologically active components in the context of prebiotic chemistry. Here we demonstrate that a nontargeted ultrahigh-resolution molecular analysis of the solvent-accessible organic fraction of Murchison extracted under mild conditions allows one to extend its indigenous chemical diversity to tens of thousands of different molecular compositions and likely millions of diverse structures. This molecular complexity, which provides hints on heteroatoms chronological assembly, suggests that the extraterrestrial chemodiversity is high compared to terrestrial relevant biological- and biogeochemical-driven chemical space.
    Keywords: Meteoroids ; Extraterrestrial Environment -- Chemistry ; Organic Chemicals -- Analysis
    ISSN: 00278424
    E-ISSN: 1091-6490
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  • 4
    Language: English
    In: Journal of agricultural and food chemistry, 13 July 2011, Vol.59(13), pp.7237-45
    Description: Botrytis cinerea infection of grape berries leads to changes in the chemical composition of grape and the corresponding wine and, thus, affects wine quality. The metabolic effect of Botrytis infection in Champagne base wine was investigated through a (1)H NMR-based metabolomic approach. Isoleucine, leucine, threonine, valine, arginine, proline, glutamine, γ-aminobutyric acid (GABA), succinate, malate, citrate, tartarate, fructose, glucose, oligosaccharides, amino acid derivatives, 2,3-butanediol, acetate, glycerol, tyrosine, 2-phenylethanol, trigonelline, and phenylpropanoids in a grape must and wine were identified by (1)H NMR spectroscopy and contributed to metabolic differentiations between healthy and botrytized wines by using multivariate statistical analysis such as principal component analysis (PCA). Lowered levels of glycerol, 2,3-butanediol, succinate, tyrosine, valine derivative, and phenylpropanoids but higher levels of oligosaccharides in the botrytized wines were main discriminant metabolites, demonstrating that Botrytis infection of grape caused the fermentative retardation during alcoholic fermentation because the main metabolites responsible for the differentiation are fermentative products. Moreover, higher levels of several oligosaccharides in the botrytized wines also indicated the less fermentative behavior of yeast in the botrytized wines. This study highlights a metabolomic approach for better understanding of the comprehensive metabolic influences of Botrytis infection of grape berries in Champagne wines.
    Keywords: Botrytis ; Fruit -- Metabolism ; Plant Diseases -- Microbiology ; Vitis -- Microbiology ; Wine -- Analysis
    ISSN: 00218561
    E-ISSN: 1520-5118
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  • 5
    Language: English
    In: Analytical and bioanalytical chemistry, September 2011, Vol.401(5), pp.1513-21
    Description: The polyphenols, for example stilbenes and flavonoids, are an important family of compounds present in grapes and wines. Several studies have shown that stilbenes are antioxidants and cancer-preventing agents. For the first time, eight natural stilbenes (trans-resveratrol, trans-piceid, cis-piceid, trans-astringin, trans-piceatannol, (+)-trans-ε-viniferin, pallidol, and hopeaphenol), isolated and purified from Vitis vinifera, were simultaneously analysed by ultra-high-pressure liquid chromatography coupled with photodiode-array detection. Separation of the stilbenes by UHPLC was optimized with the assistance of "Quality-by-Design" commercial software. Four different reversed-phase columns packed with 1.5-1.7-μm particles were tested and compared for their retention behaviour and separation efficiency. On the basis of the performance characteristics determined, the VisionHT C18 HL column was selected for the stilbenes studied, because resolution of the critical pair was 1.5 with a peak width of 2-4 s. The optimized method resulted in highly repeatable retention times (RSD 0.03-0.07%), peak areas (RSD 3-6%), and linear ranges were between 0.005 and 50 mg L(-1) for most of the compounds. All stilbenes, except trans-astringin, trans-piceatannol, and pallidol were identified and quantified in Burgundy red wines at different concentrations after direct injection of the wines.
    Keywords: Chromatography, High Pressure Liquid -- Methods ; Stilbenes -- Analysis ; Wine -- Analysis
    ISSN: 16182642
    E-ISSN: 1618-2650
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  • 6
    Language: English
    In: Analytical Chemistry, Oct 6, 2015, Vol.87(19), p.9563(4)
    Description: The article describes the molecular formula assignments comprising exactly five nitrogen and two sulfur atoms in dissolved organic matter (DOM) data sets: the molecular class CHO[N.sub.5][S.sub.2] using using high-field Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS). It is found that the presence of such components in DOM under tripeptide Met-His-Cys formed with the formula [C.sub.14][H.sub.23][O.sub.4][N.sub.5][S.sub.2] cannot be excluded, however, components containing 5 N and 2 S should not be assumed to be highly abundant.
    Keywords: Fourier Transforms – Usage ; Mass Spectrometry – Analysis ; Peptides – Chemical Properties
    ISSN: 0003-2700
    Source: Cengage Learning, Inc.
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  • 7
    Language: English
    In: Analytical chemistry, 06 October 2015, Vol.87(19), pp.9563-6
    Description: The analysis of dissolved organic matter (DOM) using high-field Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS) poses challenges in molecular formula assignment. The consideration of (13)C isotopes provides new insights into the consistent elemental formula solutions. Modern software helps to overcome misinterpretation, but false assignments of molecular classes to mass peaks have rarely been elucidated until now. It will be demonstrated that this can be important with formula assignments comprising exactly five nitrogen and two sulfur atoms in DOM data sets: the molecular class CHON5S2. The existence of such components in DOM under tripeptide Met-His-Cys formed with the formula C14H23O4N5S2 cannot be excluded; however, components containing 5 N and 2 S should be suspected to not be highly abundant. The true elemental compositions of such unusual "N5S2 moieties" were calculated using Suwannee River fulvic acid (SRFA) data from the literature and one data set from acidic pit lake pore water. The replacement of a H3N5S2 moiety with a (13)C1(12)C5O4 moiety explained more than 95% of the questionable "N5S2 moieties". This finding was proved by calculation of δ(13)C‰ values from relative peak intensities.
    Keywords: Software ; Computer Programs ; Lakes ; Fourier Transforms ; Data Sets ; Dissolved Organic Matter ; Porosity ; Mathematical Analysis ; Analysis (MD) ; Chemical Analysis (Ep) ; Chemical Analysis (Ed) ; Chemical Analysis (EC);
    ISSN: 00032700
    E-ISSN: 1520-6882
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  • 8
    Language: English
    In: ELECTROPHORESIS, June 2010, Vol.31(12), pp.2070-2079
    Description: Free‐flow electrophoresis (FFE), a preparative free zone electrophoretic method, was used offline in conjunction with ultrahigh‐resolution FT/ion cyclotron resonance ‐MS to resolve the complexity of Suwannee River fulvic acid (SRFA). Before MS, the FFE separation conditions and the compatibility with ESI were optimized. The constituents in SRFA were effectively separated based on their charge states and sizes. The obtained mass spectra were compared by means of van Krevelen diagrams and the calculated aromaticity indices of the individual constituents were used to describe the distribution of aromatic/unsaturated structures across the FFE‐fractionated samples. The consolidated number of ions observed within the individual SRFA fractions were much higher than those of the bulk samples alone, demonstrating extensive ion suppression effects in bulk SRFA likely also operating in the analysis of complex biogeochemical mixtures in flow injection mode. The FFE approach allows for producing sizable amounts of sample from dilute solutions, which can be easily fractionated into dozens of individual samples with the possibility of further in‐depth characterization.
    Keywords: Esi ; Free‐Flow Electrophoresis ; Ft Ion Cyclotron Resonance Ms ; Fulvic Acid ; Humic Substances
    ISSN: 0173-0835
    E-ISSN: 1522-2683
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  • 9
    Language: English
    In: Proceedings of the National Academy of Sciences of the United States of America, 14 March 2017, Vol.114(11), pp.2819-2824
    Description: The rich diversity and complexity of organic matter found in meteorites is rapidly expanding our knowledge and understanding of extreme environments from which the early solar system emerged and evolved. Here, we report the discovery of a hitherto unknown chemical class, dihydroxymagnesium carboxylates [(OH)MgOCR], in meteoritic soluble organic matter. High collision energies, which are required for fragmentation, suggest substantial thermal stability of these Mg-metalorganics (CHOMg compounds). This was corroborated by their higher abundance in thermally processed meteorites. CHOMg compounds were found to be present in a set of 61 meteorites of diverse petrological classes. The appearance of this CHOMg chemical class extends the previously investigated, diverse set of CHNOS molecules. A connection between the evolution of organic compounds and minerals is made, as Mg released from minerals gets trapped into organic compounds. These CHOMg metalorganic compounds and their relation to thermal processing in meteorites might shed new light on our understanding of carbon speciation at a molecular level in meteorite parent bodies.
    Keywords: Fourier Transform Ion Cyclotron Resonance Mass Spectrometry ; Astrochemistry ; Metalorganic Chemistry ; Meteorites ; Organic Evolution
    ISSN: 00278424
    E-ISSN: 1091-6490
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  • 10
    Language: English
    In: Analytical Chemistry, Oct 1, 2010, Vol.82(19), p.8017(10)
    Description: Complementary molecular and atomic signatures obtained from Fourier transform ion cyclotron resonance (FTICR) mass spectra and NMR spectra provided unequivocal attribution of CHO, CHNO, CHOS, and CHNOS molecular series in secondary organic aerosols (SOA) and high-resolution definition of carbon chemical environments. Sulfate esters were confirmed as major players in SOA formation and as major constituents of its water-soluble fraction (WSOC). Elevated concentrations of S[O.sub.2], sulfate, and photochemical activity were shown to increase the proportion of SOA sulfur-containing compounds. Sulfonation of CHO precursors by means of heterogeneous reactions between carbonyl derivatives and sulfuric acid in gas-phase photoreactions was proposed as a likely formation mechanism of CHOS molecules. In addition, photochemistry induced oligomerization processes of CHOS molecules. Methylesters found in methanolic extracts of a SOA subjected to strong photochemical exposure were considered secondary products derived from sulfate esters by methanolysis. The relative abundance of nitrogen-containing compounds (CHNO and CHNOS series) appeared rather dependent on local effects such as biomass burning. Extensive aliphatic branching and disruption of extended NMR spin-systems by carbonyl derivatives and other heteroatoms were the most significant structural motifs in SOA. The presence of heteroatoms in elevated oxidation states suggests a clearly different SOA formation trajectory in comparison with established terrestrial and aqueous natural organic matter. 10.1021/ac101444r
    Keywords: Mass Spectrometry -- Methods ; Mass Spectrometry -- Equipment And Supplies ; Sulfates -- Usage ; Photochemical Smog -- Usage ; Photochemical Smog -- Composition ; Aerosols -- Chemical Properties ; Aerosols -- Environmental Aspects ; Aerosols -- Identification And Classification ; Nuclear Magnetic Resonance Spectroscopy -- Methods ; Nuclear Magnetic Resonance Spectroscopy -- Equipment And Supplies ; Atmospheric Chemistry -- Research
    ISSN: 0003-2700
    Source: Cengage Learning, Inc.
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