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Isocorynoxeine is one of the main alkaloids in Chinese medicinal herbs, and has pharmacological activities such as antihypertensive, sedative, anticonvulsant, and neuronal protection. It is an effective component of Uncaria for the treatment of hypertension. In this study, we used a fast and sensitive ultra-performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) to detect isocorynoxeine in rat plasma and investigated its pharmacokinetics in rats. Six rats were given isocorynoxeine (15 mg/kg) by intraperitoneal (i.p.) administration. Blood (100 μL) was withdrawn from the caudal vein at 5 and 30 min and 1, 2, 4, 6, 8, 12, and 24 h after administration. Chromatographic separation was achieved using a UPLC BEH C18 column using a mobile phase of acetonitrile–0.1% formic acid with gradient elution. Electrospray ionization (ESI) tandem mass spectrometry in the multiple reaction monitoring (MRM) mode with positive ionization was applied. Intra-day and inter-day precisions (relative standard deviation, %RSD) of isocorynoxeine in rat plasma were lower than 12%. The method was successfully applied in the pharmacokinetics of isocorynoxeine in rats after intraperitoneal administration. The t 1/2 of isocorynoxeine is 4.9 ± 2.1 h, which indicates quick elimination.

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Berendsen, B.J.A., Essers, M.L., Stolker, A.A.M. & Nielen, M.W.F. (2011): Quantitative trace analysis of eight chloramphenicol isomers in urine by chiral liquid chromatography coupled to tandem mass spectrometry. J. Chromatogr. A ., 1218 , 7331

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JPC - Journal of Planar Chromatography - Modern TLC
Authors: Emil Mincsovics, Péter Ott, Ágnes Alberti, Andrea Böszörményi, Éva Héthelyi, Éva Szőke, Ágnes Kéry, Éva Lemberkovics, and Ágnes Móricz

Bioassay-guided isolation of antibacterial components of chamomile flower methanol extract was performed by overpressured layer chromatography (OPLC) with on-line detection, fractionation combined with sample clean-up in-situ in the adsorbent bed after off-line sample application. The antibacterial effect of the eluted fractions and of those compounds remaining on the adsorbent layer after separation was tested with direct bioautography (DB) against the bioluminescent Pseudomonas savastanoi pv. maculicola and Vibrio fischeri. The fractions with high biological activity were analyzed by solid phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) and liquid chromatography and tandem mass spectrometry (LC-MS/MS). Two active uneluted compounds were characterized by off-line OPLC-MS using a thin-layer chromatography (TLC)-MS interface. Mainly, essential oil components, coumarins, flavonoids, phenolic acids, and fatty acids were identified in the active fractions.

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Summary

A new liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for simultaneous determination of glycyrrhizin, formononetin, glycyrrhetinic acid, liquiritin, isoliquiritigenin, and licochalcone A in licorice. An Eclipse Plus C18 column (I.D. 4.6 × 100 mm, 3.5 μm particle size; Agilent) was used in the analysis. Electrospray ionization (ESI)-tandem interface in the negative mode was performed, and multiple reaction monitoring (MRM) was employed with the precursor multiple reaction monitoring production combination for the determination of six analytes. The average recoveries ranged from 98.30% to 100.13% with relative standard deviations (RSDs) ≤ 1.95%, and limits of detection (LODs) ranged from 2.1 to 3.6 pg. The applicability of this analytical approach was confirmed by the successful analysis of six samples. The results indicated that the established method was validated, sensitive, and reliable for the determination of six analytes in licorice.

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Acta Chromatographica
Authors: Gobinda Chandra Acharya, Naresh Ponnam, Meenu Kumari, Tapas Kumar Roy, Kodthalu Seetharamaiah Shivashankara, and Manas Ranjan Sahoo

Abstract

Spiny coriander (Eryngium foetidum L.) is a perennial medicinal herb grown in the tropical regions worldwide. In India, it is used as a potential spice for garnishing and flavoring the dishes and treating several ailments. Eryngium spp. found in coastal Odisha, India has a strong aroma similar to the seasonal Coriandrum. The volatile flavor constituents of the unique plants were analyzed through headspace solid-phase microextraction (HS-SPME) using capillary gas chromatography (GC) and gas chromatography-tandem mass spectrometry (GC–MS/MS). The volatile compounds exhibited high chemodiversity, with 10-undecenal as the major component in leaves (44.98%) and branches (57.43%). Fourier-transform infrared (FTIR) spectroscopy identified eight major peaks grouped into six main regions. Chemo profiles of these two corianders were overlapped and showed similar area differences in the spectral peak. The lesser-known perennial Eryngium with high chemodiversity would be a better alternative to the seasonal coriander for aromatic, pharmaceutical, and industrial uses.

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The aim of this study was to assess the impact of hanging position of hunted pheasant carcasses (secured by the head as compared to hanging position secured by the legs) on the biogenic amine concentration in the thigh and breast muscles. The carcasses of feathered game (Phasianus colchicus), left entirely untreated after hunting and placed in a storage space at a pre-set temperature of 7 °C for 21 days were used in the study. Samples of breast and thigh muscles were taken at regular weekly intervals. Measurement of biogenic amines (putrescine, cadaverine, tyramine, tryptamine, histamine, phenylethylamine) was based on high-performance liquid chromatography coupled with triple quadrupole tandem mass spectrometry. Higher biogenic amine concentrations were detected in the muscles (both breast and thigh) of pheasants hanging by their legs compared to pheasants hanging by their heads (no statistically significant difference in biogenic amine concentration between monitored groups was, however, established). Higher concentrations of biogenic amines were found in the thigh muscles compared to breast muscles in both monitored groups. The obtained results show, that hanging the carcasses of pheasants during storage by the head is more suitable method in term of biogenic amine concentration than storing carcasses hanging by the legs.

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Abstract

Chronic hepatitis B virus (HBV) carriers may develop hepatocellular carcinoma (HCC) by a wide range of mechanisms including angiogenesis. We show that HBV replication induces the expression of angiogenic proteins interleukin 6 (IL6) and cyclooxygenase-2 (Cox2). Interestingly, ibuprofen (a Cox2 inhibitor) is found to attenuate the levels of IL6 and Cox 2 which are induced by HBV replication.

The mechanism of attenuation of angiogenic proteins by ibuprofen was further investigated. Our results show that HBx is involved in the increase of the expression of Cox2 through the NFκB pathway. However, the expression of Cox2 is decreased when the HBx-expressing cells are incubated with ibuprofen. The contrasting effect of HBx on Cox2 is found to be determined by differential dimer formation among the members of the NFκB family of proteins, including NFκB, RelA, and C-rel. Specifically, HBx alone results in dimer formation between NFκB and RelA, while the combined presence of HBx and ibuprofen leads to the formation of NFκB and C-rel. Additional information on the interaction network involving HBx, ibuprofen, and NFκB pathways is revealed by two-dimensional liquid chromatography-tandem mass spectrometry proteomics analysis. Taken together, our findings provide new insights on the angiogenesis induced by HBV replication.

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Patrinia scabiosaefolia Fisch. (PSF), a well-known traditional Chinese medicine, has been demonstrated to show therapeutic effects on inflammatory bowel disease. In this study, a rapid and sensitive method using ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF-MS) was developed for identification of the major constituents in PSF. The separation analysis was performed on Waters Acquity UPLC system, and the accurate mass of molecules and their fragment ions were determined by Q-TOF-MS. Thirty-one constituents, including triterpenoids, iridoids, flavonoids, and organic acids were detected and tentatively deduced on the basis of their element compositions, tandem mass spectrometry (MS/MS) data, and relevant literatures. Twelve constituents were discovered for the first time in PSF. The results demonstrated that hederagenin-type and oleanolic acid-type saponins were the main constituents of PSF. Our work provides a certain foundation for further quantitation of major chemical constituents and in vivo pharmacokinetic studies of PSF. Moreover, the analytical approach developed herein has proven to be generally applicable for profiling the chemical constituents in traditional Chinese medicines (TCMs) and other complicated mixtures.

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Acta Chromatographica
Authors: Su-su Bao, Jian Wen, Teng-hui Liu, Bo-wen Zhang, Chen-chen Wang, and Guo-xin Hu

Olmutinib (Olita™) is an oral third-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) which is used to treat non-small cell lung cancer (NSCLC). A simple, rapid, and sensitive method based on ultra-performance liquid chromatography tandem mass spectrometry (UHPLC–MS/MS) has been developed for the determination of olmutinib. Sample preparation was performed following simple one-step protein precipitation with acetonitrile. Olmutinib and internal standard (dasatinib) were separated on an Eclipse Plus C18 RRHD (2.1 × 50 mm, 1.8 μm) column. The mobile phase consisted of acetonitrile–0.1% formic acid in water with gradient elution. A total run time of 1.7 min was achieved. Detection was performed on a positive-ion electrospray ionization mass spectrometer in multiple reaction monitoring (MRM) mode, using transitions of m/z 487.2 → 402.1 for olmutinib and m/z 488.2 → 401 for dasatinib (IS), respectively. The calibration curve (R 2 = 0.999) was linear over the range of 1–500 ng/mL. The recovery of olmutinib ranged from 85.8% to 95.5%. This method can be applied to pharmacokinetic studies of olmutinib.

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Summary

A new liquid chromatography tandem mass spectrometry (LC-MS/MS) assay for the quantification of seven isoflavones (daidzin, genistin, ononin, daidzein, glycitein, genistein, and formononetin) and coumestrol in vegetable extracts was developed. The separation was performed on a Zorbax SB-C18 column with a mixture of methanol (solvent A) and 0.1% (υ/υ) acetic acid in water (solvent B) under gradient conditions at 50°C with a flow rate of 1 mL min−1. The detection of analytes was performed by electrospray ionization, negative ionisation, in non-reactive MS2 mode for aglycons or in reactive MS2 mode for glycosides. The method shows a good linearity (r 2 > 0.9948) over the concentration range of 40–4000 ng mL−1 for all analytes, a good precision (CV < 11%) and accuracy (<10%). The method was successfully applied to quantify the isoflavones and coumestrol in vegetable extracts obtained from red clover (Trifolium pratense L., Fabaceae) and dyer's greenweed (Genista tinctoria L., Fabaceae) and can be used in the chemical characterization of vegetables with phytoestrogen content.

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