• Biomolecules & Therapeutics
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• v.4 no.3
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• pp.251-256
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• 1996

The metabolism of carbinoxamine, 2-[(4-chlorophenyl)-2-pyridinyl-methoxy]-N, N-dimethylethaneamine, was studied in adult male volunteers after an oral dose of 15 mg. Solvent extracts of urine obtained with or without enzyme hydrolysis were analyzed by gas chromatography-mass spectrometry after derivatization with MSTFA/TMSCl (N-methyl-N-trimethylsilyltrifluoroacetamide/trimethyl chlorosilane). The structures of metabolites were determined based on the electron impact (EI) and chemical ionization (CI) mass spectra. Nonconjugated metabolites identified in the urine were carbinoxamine, nor-carbinoxamine, and bits-nor-carbinoxamine. Parent drug, nor-carbinoxamine, and bits-nor-carbinoxamine were also detected as conjugated forms. These metabolites observed in human urine were different from those previously reported in the rat. Urinary excretions of carbinoxamine were reached to maxima in 4 hours after drug administration with 4.9%-8.1% and 2.5-4.2% of the dose excreted during 24 h as carbinoxamine and its glucuronide, respectively.

• Bulletin of the Korean Chemical Society
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• v.33 no.1
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• pp.60-64
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• 2012

Silver(I) [bis(alkylthio)methylene]malonates were synthesized from the reaction of silver nitrate and potassium [bis(alkylthio)methylene]malonates. The structures of the Ag complexes were characterized with nuclear magnetic resonance (NMR), inductively coupled plasma atomic emission spectrometry (ICP-AES) and elemental analysis. Ag nanoparticles (NPs) were obtained from the decomposition of the Ag complexes in 1,2-dichlorobenzene at $110^{\circ}C$ without an additional surfactant. The average sizes of the Ag NPs are in the range of 5.1-6.3 nm and could be controlled by varying the length of the alkyl chain. The optical properties, crystalline structure and surface composition of Ag NPs were characterized with ultraviolet-visible (UV-visible) spectroscopy, transmission electron microscopy (TEM), X-ray diffraction (XRD), gas chromatography-mass spectrometry (GC-MS), X-ray Photoelectron Spectroscopy (XPS) and thermal gravimetric analysis (TGA).

• Archives of Pharmacal Research
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• v.19 no.6
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• pp.566-569
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• 1996

A sensitivity method has been developed for the detection and determination of niflmic acid(NA) in human urine. Samples were extracted with diethylether. Flunixin (FN) was added to the sample prior to extraction as an internal standard. Niflumic acid was converted to its methyl derivative and analyzed by capillary gas chromatography/negative chemical isonization mass spectrometry. Using selected ion monitoring (SIM), the levels of NA down to 5 pg/ml could be detected in 5 ml spiked urine sample. Calibration curve was linear over the range of 0.5 ppm-50 ppm. The recovery of niflumic acid from urine at 40 pg/ml was to be $91.7{\pm}3.8(n=3)$ and the coefficient of variation was 4.1%.

• Bulletin of the Korean Chemical Society
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• v.19 no.1
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• pp.45-50
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• 1998

Most organophosphorus pesticides may be metabolized to yield some common phosphates in human or in animals, and these metabolites may be used as the exposure biomarkers to pesticides. In this study, we developed the extraction method of four phosphate metabolites from the spiked human urine in high recovery by the solid phase extraction with a reverse-phase cartridge (cyclohexyl silica) followed by the elution with methanol. The extracted urinary metabolites were derivatized with hexamethyldisilazane/trimethyl-chlorosilane/pyridine (2 : 1 : 10, v/v/v) and identified by gas chromatography/mass spectrometry. Calibration curve obtained from each metabolite standard using by GC/MS/SIM has shown good linearity and detection limits of metabolites were the range of 0.05-0.1 ㎍/㎖ in urine. Phenthoate, one of the organophosphorus pesticides, was orally administrated to rats. Four metabolites were detected in the rat urine. The results of this study may be applied to development of exposure biomarkers for monitoring of environmental pollutants.

• Korean Journal of Environmental Agriculture
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• v.36 no.3
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• pp.154-160
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• 2017

BACKGROUND:This study was carried out to establish an efficient sample preparation for the simultaneous determination of bisphenols (BPs) in river water samples using gas chromatography-mass spectrometry (GC-MS). Sample preparation was examined with conventional extraction methods, such as solid-phase extraction (SPE) and liquid-liquid extraction (LLE), and their efficiency was compared with validation results, including linearity of calibration curve, method detection limit (MDL), limit of quantification (LOQ), accuracy, and precision. METHODS AND RESULTS:The BPs (bisphenol A, BPA; bisphenol B, BPB; bisphenol C, BPC; bisphenol E, BPE; bisphenol F, BPF; bisphenol S, BPS) were analyzed using GC-MS. The range of MDLs by SPE and LLE methods was $0.0005{\sim}0.0234{\mu}g/L$ and $0.0037{\sim}0.2034{\mu}g/L$, and that of LOQs was $0.0015{\sim}0.0744{\mu}g/L$ and $0.0117{\sim}0.6477{\mu}g/L$, respectively. The calibration curve obtained from standard solution of $0.004{\sim}4.0{\mu}g/L$ (SPE) and $0.016{\sim}16{\mu}g/L$ (LLE) showed good linearity with $r^2$ value of 0.9969 over. Accuracy was 93.2~108% and 97.4~120%, and precision was 1.7~4.6% and 0.7~6.5%, respectively. The values of MDL and LOQ resulted from the SPE method were higher than those from the LLE method, particularly those values of BPA were highest among the BPs. Based on the results, the SPE method was applied to determine the BPs in river water samples. Water samples were collected from mainstream, tributary and sewage wastewater treatment plants (SWTPs) in the Yeongsan river basin. The concentration of BPB, BPC, BPE, BPF and BPS were not detected in all sites, whereas BPA was ranged $0.0095{\sim}0.2583{\mu}g/L$, which was $0.0166{\sim}0.0810{\mu}g/L$ for mainstreams, $0.0095{\sim}0.2583{\mu}g/L$ for tributaries, $0.0352{\sim}0.1217{\mu}g/L$ for SWTPs. CONCLUSION: From these results, the SPE method was very effective for the simultaneous determination of BPs in river water samples using GC-MS. We provided that it is a convenient, reliable and sensitive method enough to monitor and understand the fate of the BPs in aquatic ecosystems.

• Journal of Applied Biological Chemistry
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• v.61 no.2
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• pp.131-134
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• 2018

The stem of Chrysanthemum morifolium, 'Baekma', were repeatedly extracted with 80% aqueous MeOH and the concentrates was partitioned into ethyl acetate (EtOAc), n-butyl alcohol and $H_2O$ fraction. The repeated silica gel and octadecyl silica gel column chromatographies for the EtOAc fractions led to isolation of two glycosyl glycerides. The chemical structures of the compounds were determined as (2S)-1-O-${\beta}-{\text\tiny{D}}$-galactopyranosyl-2,3-dilinoleoylglycerol (1) and (2S)-1-O-${\beta}-{\text\tiny{D}}$-galactopyranosyl-2,3-dipalmitoylglycerol (2) based on spectroscopic data anlyses including nuclear magnetic resonance, mass sperctrometry, and infrared spectrometry and gas chromatography mass spectrometry.

• Mass Spectrometry Letters
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• v.4 no.4
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• pp.59-66
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• 2013

A metabolomics study was conducted to identify urinary biomarkers for breast cancer, using gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS), analyzed by principal components analysis (PCA) as well as a partial least squares-discriminant analysis (PLS-DA) for a metabolic pattern analysis. To find potential biomarkers, urine samples were collected from before- and after-mastectomy of breast cancer patients and healthy controls. Androgens, corticoids, estrogens, nucleosides, and polyols were quantitatively measured and urinary metabolic profiles were constructed through PCA and PLS-DA. The possible biomarkers were discriminated from quantified targeted metabolites with a metabolic pattern analysis and subsequent screening. We identified two biomarkers for breast cancer in urine, ${\beta}$-cortol and 5-methyl-2-deoxycytidine, which were categorized at significant levels in a student t-test (p-value < 0.05). The concentrations of these metabolites in breast cancer patients significantly increased relative to those of controls and patients after mastectomy. Biomarkers identified in this study were highly related to metabolites causing oxidative DNA damage in the endogenous metabolism. These biomarkers are not only useful for diagnostics and patient stratification but can be mapped on a biochemical chart to identify the corresponding enzyme for target identification via metabolomics.

• Food Science and Biotechnology
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• v.17 no.3
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• pp.669-674
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• 2008

Zanthoxylum schinifolium and Zanthoxylum piperitum A.P. DC. belong to the Rutaceae family and are perennial, aromatic, and medicinal herbaceous plants. In this study, their aroma compounds were isolated by steam distillation extraction using a Clevenger-type apparatus, and then further analyzed by gas chromatography (GC) and gas chromatograph/mass spectrometry (GC/MS). The yields of the essential oils from Z. schinifolium and Z. piperitum AP. DC. were 2.5 and 2.0%(w/w), respectively, and the color of their oils was quite similar, a pale yellow. From the distilled oil of Z. schinifolium, 60 volatile compounds which make up 87.24% of the total composition were tentatively identified, with monoterpenes predominating. $\beta$-Phellandrene (22.54%), citronellal (16.48%), and geranyl acetate (11.39%) were the predominantly abundant components of Z. schinifolium. In the essential oil of Z. piperitum AP. DC., 60 volatile flavor components constituted 94.78% of the total peak area were tentatively characterized. Limonene (18.04%), geranyl acetate (15.33%), and cryptone (8.52%) were the major volatile flavor compounds of Z. piperitum A.P. DC.

• Biomolecules & Therapeutics
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• v.1 no.2
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• pp.143-150
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• 1993

The metabolic profile of triprolidine, 2-[(4-methylphenyl)-3-(1-pyrrolidinyl-1-propenyl)] pyridine, was determined. Urinary extracts obtained with enzyme hydrolysis were derivatized with MSTFA/TMSCl (N-methyl-N-trimethylsilyl trifluoroacetamide/trimethylchlorosilane) and analyzed by GC/MSD. In human urine, which were obtained after the oral administration with triprolidine, hydroxymethyltriprolidine, triprolidine carboxylic acid, oxotriprolidine carboxylic acid and unchanged triprolidine were detected. The maximum urinary excretion rate of triprolidine and hydroxymethyltriprolidine which were extracted from human urine was at 2 to 4 hours after the drug administration. Triprolidine and hydroxymethyl triprolidine were identified by comparison with authentic standards In chromatographic and mass spectral properties. Triprolidine carboxylic acid was detected as a major metabolite of its metabolites in the urine. Oxotriprolidine carboxylic acid and triprolidine carboxylic acid were tentatively identified by the interpretation of its mass spectral patterns. These data suggest that in human, hydroxylation of either the benzyl or pyrrolidine ring can occur during triprolidine elimination.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.37 no.3
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• pp.74-80
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• 2005

The compositions of residual extractives in woodmeal, unbleached and oxygen-delignified aspen kraft pulps were investigated with gas chromatography(GC) and gas chromatography-mass spectrometry (GC-MS) with focus on fate of extractives in kraft pulping and oxygen delignification. Steryl esters and shorter retention time (shorter than palmitic acid) extractives were main extractives in aspen woodmeal. Shorter retention time extractives were well removed in kraft pulping. Sterol esters were hydrolyzed to sterols and fatty acids. Sterols and fatty acids were two major extractives classes in unbleached kraft pulps. Linoleic acid was main fatty acids in unbleached pulps compared with palmitic acid which is generally found in aspen woodmeal. Sterolsand fatty acids were also two major extractives classes in oxygen-delignified kraft pulps. However, linoleic acid was well removed in oxygen delignification.