2D UHPLC
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Effective process, including a cartridge packing polypropylene fiber sorbent modified by following on-line polydopamine coating, for on-line solid phase extraction in 2D UHPLC system has been developed. Hydrophobic surface of mechanically stable polypropylene fibers was hydrophilized using an automated and reproducible in situ coating process to enable good wettability and effective extraction of polar compounds. Polymerization mixture consisting dopamine and TRIS buffer was circulated through the cartridge containing polypropylene fibers using a peristaltic pump to achieve polymerization. This process was optimized in terms of dopamine amount in the polymerization mixture, its flow rate, and polymerization time. Best results were obtained with 25 mL polymerization mixture containing 20 mg dopamine circulated through the cartridge at a flow rate of 2.07 mL min-1 for 60 min. Prepared cartridges were evaluated via measurement of the recovery and reproducibility using chlorogenic acid as a model compound. Overall reproducibility of our multistep process including eight cartridges in 2D UHPLC system, each measured in triplicate, was 3.61% (n = 24).
- Klíčová slova
- 2D UHPLC, Chlorogenic acid, Fibrous sorbent, On-line coating, On-line solid phase extraction, Sorbent modification,
- Publikační typ
- časopisecké články MeSH
Three dimensions of chromatographic separation, using split-flow two-dimensional liquid chromatography (SF-2D-LC) with two parallel second dimensions, LC × 2LC, combined with quadruple parallel mass spectrometry (LC3MS4) is demonstrated for analysis of NIST SRM 1849a adult/infant formula. The first dimension, 1D, was a conventional non-aqueous reversed-phase (NARP) HPLC separation using two C18 columns in series, followed by detection using an ultraviolet (UV) detector, a fluorescence detector (FLD), with flow then split to a corona charged aerosol detector (CAD), and then dual parallel mass spectrometry (MS), conducted in atmospheric pressure photoionization (APPI) and electrospray ionization (ESI) modes. The first second dimension, 2D(1), UHPLC was conducted on a 50.0 mm C30 column using a NARP-UHPLC parallel gradient for separation of short-chain triacylglycerols (TAGs) from long-chain TAGs, with detection by UV and ESI-MS. The second dimension, 2D(2), UHPLC was conducted using a 100.0 mm C30 column with a NARP-UHPLC parallel gradient for improved separation of TAG isomers, with detection by UV, an evaporative light scattering detector, and high-resolution, accurate-mass (HRAM) ESI-MS. Transferred eluent dilution was used to refocus peaks and keep them sharp during elution in both 2Ds. The separation space in the 2D(2) was optimized using multi-cycle (aka, "constructive wraparound") elution, which employed flow rate programming. In the 1D, calibration lines for quantification of fat-soluble vitamins were constructed. A lipidomics approach to TAG identification and quantification by HRAM-ESI-MS was applied to the 2D(2). These experiments can be represented: LC1MS2 × (LC1MS1 + LC1MS1) = LC3MS4, or three-dimensional liquid chromatography with quadruple parallel mass spectrometry.
- Klíčová slova
- 2D-LC, 3D-LC, APPI-MS, ESI-MS, Lipidomics, Two-dimensional LC,
- MeSH
- dospělí MeSH
- hmotnostní spektrometrie s elektrosprejovou ionizací * MeSH
- lidé MeSH
- náhražky mateřského mléka * MeSH
- triglyceridy MeSH
- vysokoúčinná kapalinová chromatografie MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- triglyceridy MeSH
Beta-bitter acids of hops (lupulones) revealed sedative and antidepressant-like effects in animal studies. Transformation of β-acids during beer brewing leads to the formation of tricyclic transformation products, which have a close structural analogy to hyperforin. The latter compound is responsible for the antidepressant activity of St. John's wort by activation of TRPC6 cation channels in neuronal-like cells leading to Ca2+ influx. In this study, nortricyclolupones, dehydrotricyclolupones, and tricyclolupones were isolated from a wort-boiling model and their structures were elucidated by UHPLC-DAD, UHPLC-ESI--MS/MS and 1D/2D-NMR spectroscopy. Beta-bitter acids and their transformation products induced Ca2+ influx in PC12 cells to the same extent as hyperforin. Application of a Ca2+-free environment abolished the Ca2+ elevation, indicating that the increase is mediated by influx across the plasma membrane. Thus, activation of neuronal-like Ca2+-channels by lupulones and tricyclolupones represent a novel mechanism contributing to the antidepressant activity of hops.
- Klíčová slova
- Antidepressant, Ca(2+) influx, Hops, Lupulones, Neuronal-like cells, Tricyclolupones, β-bitter acids,
- MeSH
- buněčná membrána metabolismus MeSH
- buňky PC12 MeSH
- krysa rodu Rattus MeSH
- neurony účinky léků metabolismus MeSH
- terpeny chemie metabolismus farmakologie MeSH
- transport proteinů účinky léků MeSH
- vápník metabolismus MeSH
- vápníkové kanály metabolismus MeSH
- zvířata MeSH
- Check Tag
- krysa rodu Rattus MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- lupulon MeSH Prohlížeč
- terpeny MeSH
- vápník MeSH
- vápníkové kanály MeSH
Although cell wall polymers play important roles in the tolerance of plants to abiotic stress, the effects of salinity on cell wall composition and metabolism in grasses remain largely unexplored. Here, we conducted an in-depth study of changes in cell wall composition and phenolic metabolism induced upon salinity in maize seedlings and plants. Cell wall characterization revealed that salt stress modulated the deposition of cellulose, matrix polysaccharides and lignin in seedling roots, plant roots and stems. The extraction and analysis of arabinoxylans by size-exclusion chromatography, 2D-NMR spectroscopy and carbohydrate gel electrophoresis showed a reduction of arabinoxylan content in salt-stressed roots. Saponification and mild acid hydrolysis revealed that salinity also reduced the feruloylation of arabinoxylans in roots of seedlings and plants. Determination of lignin content and composition by nitrobenzene oxidation and 2D-NMR confirmed the increased incorporation of syringyl units in lignin of maize roots. Salt stress also induced the expression of genes and the activity of enzymes enrolled in phenylpropanoid biosynthesis. The UHPLC-MS-based metabolite profiling confirmed the modulation of phenolic profiling by salinity and the accumulation of ferulate and its derivatives 3- and 4-O-feruloyl quinate. In conclusion, we present a model for explaining cell wall remodeling in response to salinity.
- Klíčová slova
- Zea mays, abiotic stress, cell wall, ferulic acid, lignification, p-coumaric acid, salinity, xylan,
- MeSH
- buněčná stěna chemie metabolismus MeSH
- celulosa analýza chemie MeSH
- fenoly metabolismus MeSH
- kořeny rostlin metabolismus MeSH
- kukuřice setá cytologie růst a vývoj metabolismus MeSH
- kyseliny kumarové metabolismus MeSH
- lignin metabolismus MeSH
- monosacharidy analýza MeSH
- polysacharidy chemie metabolismus MeSH
- regulace genové exprese u rostlin MeSH
- rostlinné buňky metabolismus MeSH
- semenáček cytologie metabolismus MeSH
- solný stres fyziologie MeSH
- xylany analýza chemie metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- arabinoxylan MeSH Prohlížeč
- celulosa MeSH
- fenoly MeSH
- ferulic acid MeSH Prohlížeč
- kyseliny kumarové MeSH
- lignin MeSH
- monosacharidy MeSH
- polysacharidy MeSH
- xylany MeSH
Seven previously undescribed sesquiterpene lactones, three known sesquiterpene lactones (ixerin D, 15-p-hydroxyphenylacetyllactucin, and 15-p-hydroxyphenylacetyllactucin-8-sulfate), and two known quinic acid derivatives (3-O-feruloylquinic acid and 3,5-di-O-caffeoylquinic acid) were isolated from Sonchus palustris L. roots. Four formerly undescribed compounds were elucidated to be 3β,14-dihydroxycostunolide-3-O-β-D-glucopyranosyl-(2-O-p-hydroxyphenylacetyl)-14-O-p-hydroxyphenylacetate, 15-p-methoxyphenylacetyllactucin, 15-p-methoxyphenylacetyllactucin-8-sulfate, and 8-p-hydroxyphenylacetyllactucin-15-sulfate. Additionally, three undescribed conjugates of lactucin and a eudesmanolide type sesquiterpenic acid, sonchpalustrin, 4″-O-methylsonchpalustrin, and isosonchpalustrin, were characterized. The structures of the newly discovered natural products were elucidated using 1D and 2D NMR spectroscopy and UHPLC-HRMS. 15-p-Hydroxyphenylacetyllactucin and 15-p-methoxyphenylacetyllactucin showed significant in vitro cytotoxicity against CEM and BJ cells with IC50 values ranging from 3.9 to 9.8 μM. Compounds 3 and 4 showed also strong anti-inflammatory activity in vitro.
- Klíčová slova
- Biological activities, Chemophenetics, Quinic acid derivatives, Schleswig-Holstein, Sesquiterpene lactones, Sonchus palustris,
- MeSH
- Asteraceae chemie MeSH
- fytogenní protinádorové látky chemie izolace a purifikace farmakologie MeSH
- fytonutrienty chemie izolace a purifikace farmakologie MeSH
- kultivované buňky MeSH
- laktony chemie izolace a purifikace farmakologie MeSH
- lidé MeSH
- proliferace buněk účinky léků MeSH
- screeningové testy protinádorových léčiv MeSH
- seskviterpeny chemie izolace a purifikace farmakologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- fytogenní protinádorové látky MeSH
- fytonutrienty MeSH
- laktony MeSH
- seskviterpeny MeSH
During a study of the diversity of soilborne fungi from Spain, a strain belonging to the family Chaetomiaceae (Sordariales) was isolated. The multigene phylogenetic inference using five DNA loci showed that this strain represents an undescribed species of the genus Amesia, herein introduced as A. hispanica sp. nov. Investigation of its secondary metabolome led to the isolation of two new derivatives (2 and 3) of the known antifungal antibiotic dactylfungin A (1), together with the known compound cochliodinol (4). The planar structures of 1-4 were determined by ultrahigh performance liquid chromatography coupled with diode array detection and ion mobility tandem mass spectrometry (UHPLC-DAD-IM-MS/MS) and extensive 1D and 2D nuclear magnetic resonance (NMR) spectroscopy after isolation by HPLC. All isolated secondary metabolites were tested for their antimicrobial and cytotoxic activities. Dactylfungin A (1) showed selective and strong antifungal activity against some of the tested human pathogens (Aspergillus fumigatus and Cryptococcus neoformans). The additional hydroxyl group in 2 resulted in the loss of activity against C. neoformans but still retained the inhibition of As. fumigatus in a lower concentration than that of the respective control, without showing any cytotoxic effects. In contrast, 25″-dehydroxy-dactylfungin A (3) exhibited improved activity against yeasts (Schizosaccharomyces pombe and Rhodotorula glutinis) than 1 and 2, but resulted in the appearance of slight cytotoxicity. The present study exemplifies how even in a well-studied taxonomic group such as the Chaetomiaceae, the investigation of novel taxa still brings chemistry novelty, as demonstrated in this first report of this antibiotic class for chaetomiaceous and sordarialean taxa.
- Klíčová slova
- Chaetomiaceae, Sordariales, antifungals, fungal secondary metabolites, metabolomics,
- Publikační typ
- časopisecké články MeSH
