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.
- MeSH
- Adult MeSH
- Spectrometry, Mass, Electrospray Ionization * MeSH
- Humans MeSH
- Infant Formula * MeSH
- Triglycerides MeSH
- Chromatography, High Pressure Liquid MeSH
- Check Tag
- Adult MeSH
- Humans MeSH
- Publication type
- Journal Article MeSH
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).
- Publication type
- Journal Article 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.
- MeSH
- Asteraceae chemistry MeSH
- Antineoplastic Agents, Phytogenic chemistry isolation & purification pharmacology MeSH
- Phytochemicals chemistry isolation & purification pharmacology MeSH
- Cells, Cultured MeSH
- Lactones chemistry isolation & purification pharmacology MeSH
- Humans MeSH
- Cell Proliferation drug effects MeSH
- Drug Screening Assays, Antitumor MeSH
- Sesquiterpenes chemistry isolation & purification pharmacology MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article 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.
- Publication type
- Journal Article MeSH
