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Gregory Genta‐Jouve Lionel Weinberg Vincent Cocandeau Yannick Maestro Olivier Paul Thomas Serge Holderith 《Chirality》2013,25(3):180-184
Coatline A ( 1 ) and α‐epi‐coatline A ( 4 ) co‐occur in the trunk extract of Andira coriacea. Inspection of their chiroptical properties led to intriguing results. After a careful examination of the experimental data used for the previously reported absolute configuration of these compounds, some uncertainties were identified. A combined theoretical approach including conformational analyses and calculation of electronic circular dichroism (ECD) spectra, in addition with experimental data obtained for schoepfin A ( 5 ) and the new schoepfin D ( 6 ) isolated from Senna quinquangulata, allowed the revision of the absolute configuration of coatlines A ( 1 ) and B ( 2 ). Chirality 25:180–184, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
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Validated Method for Strigolactone Quantification by Ultra High‐Performance Liquid Chromatography – Electrospray Ionisation Tandem Mass Spectrometry Using Novel Deuterium Labelled Standards
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Stéphanie Boutet‐Mercey François Perreau Amélie Roux Guillaume Clavé Jean‐Paul Pillot Isabelle Schmitz‐Afonso David Touboul Grégory Mouille Catherine Rameau François‐Didier Boyer 《Phytochemical analysis : PCA》2018,29(1):59-68
Introduction
Strigolactones (SLs) are important plant hormones. They are difficult to analyse because they occur in very small concentrations especially in comparison with other plant hormones and other substances can interfere with their detection.Objective
To develop a procedure for the extraction, purification and quantification of SLs from plant roots.Methodology
Samples were prepared by extraction of plant root tissues with ethyl acetate. Then the extracts were further purified with silica column chromatography. The natural SLs in the final extracts were quantified using novel deuterium labelled SLs. The results of the methodology were compared with those of the procedure of Yoneyama and coworkers.Results
This procedure required about 1‐g root samples to detect and quantify simultaneously the SLs (orobanchyl acetate and fabacyl acetate) concentration with high reliability.Conclusion
A method was developed for determining endogenous fabacyl acetate and orobanchyl acetate in plant tissue based on novel deuterium labelled standards. A method of orobanchol quantification using a synthetic SL GR24 as internal standard was proposed. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献5.
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Rafika Brakni Monia Ali Ahmed Pauline Burger Aurélie Schwing Grégory Michel Christelle Pomares Lillia Hasseine Laurent Boyer Xavier Fernandez Anne Landreau Thomas Michel 《化学与生物多样性》2018,15(4)
Lichens are complex symbiotic organisms able to produce a vast array of compounds. The Algerian lichen diversity has only prompted little interest even given the 1085 species listed. Herein, the chemodiversity of four Algerian lichens including Cladonia rangiformis, Ramalina farinaceae, R. fastigiata, and Roccella phycopsis was investigated. A dereplication strategy, using ultra high performance liquid chromatography‐high resolution‐electrospray ionization‐mass spectrometry (UHPLC‐HRMS/MS), was carried out for a comprehensive characterization of their substances including phenolics, depsides, depsidones, depsones, dibenzofurans, and aliphatic acids. Some known compounds were identified for the first time in some species. Additionally, the lichenic extracts were evaluated for their antifungal and antimicrobial activities on human pathogenic strains (Candida albicans, C. glabrata, Aspergillus fumigatus, Staphylococcus aureus, and Escherichia coli). Cyclohexane extracts were found particularly active against human pathogenic fungi with MIC80 values ranging from 8 to 62.5 μg/mL, without cytotoxicity. This study highlights the therapeutic and prophylactic potential of lichenic extracts as antibacterial and antifungal agents. 相似文献
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An immunoadjuvant saponin fraction from Quillaja brasiliensis leaves was investigated by direct infusion and liquid chromatography/electrospray ionization ion trap multiple-stage mass spectrometry in negative ion mode (DI-ESI-IT-MSn and LC-ESI-IT-MSn). The aglycone and the sequence of the oligosaccharide residues at C-3 and C-28 were characterized based on MS2 and MS3 experiments of the [MH]− ions. According to their [MH]− ions, characteristic product ions and retention times, 27 bidesmosidic saponins, bearing four types of triterpenic aglycones, were tentatively identified. 相似文献
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Simultaneous Determination of Bioactive Monoterpene Indole Alkaloids in Ethanolic Extract of Seven Rauvolfia Species using UHPLC with Hybrid Triple Quadrupole Linear Ion Trap Mass Spectrometry
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Flavonoids are important secondary plant metabolites believed to be present mainly in land plants. As phenolics were detected previously in microalgae using photometric assays, we wanted to investigate the nature of these phenolics and verify whether flavonoids are present. Therefore, in this study, we used state‐of‐the‐art ultra‐high performance liquid chromatography‐two‐dimensional mass spectrometry (UHPLC‐MS/MS) technology to investigate whether microalgae also contain flavonoids. For this, representative microalgal biomass samples from divergent evolutionary lineages (Cyanobacteria, Rhodophyta, Chlorophyta, Haptophyta, Ochrophyta) were screened for a set of carefully selected precursors, intermediates, and end products of the flavonoid biosynthesis pathways. Our data unequivocally showed that microalgae contain a wide range of flavonoids and thus must possess the enzyme pool required for their biosynthesis. Further, some of the microalgae displayed an intricate flavonoid pattern that is compatible with the established basic flavonoid pathway as observed in higher plants. This implies that the flavonoid biosynthesis pathway arose much earlier in evolution compared to what is generally accepted. 相似文献