• Journal of the Korean Chemical Society
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• v.57 no.6
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• pp.738-743
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• 2013

Linoleic acid and its metabolites have various medicinal effects with carboxylic acid functional group. General carboxylic acid compounds are discovered as glucuronide metabolites by UGT glucuronosyl transferase at liver. Consequently, glucuronides of linoleic acid metabolites are expected as potent conjugated metabolite. A previous study reported two epoxide metabolites and two dihydroxy metabolites of linoleic acid. There are prepared their glucuronic acid conjugated compounds as potent linoleic acid metabolites.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.2
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• pp.432-439
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• 2020

This study examined the metabolites in different roughage to concentrate ratios using proton nuclear magnetic resonance spectroscopy (1H-NMR). Six lactating cows were divided into two groups that were fed different roughage to concentrate ratios (HR group = 8:2, HC group = 2:8). Feces samples were collected individually at one time, and the metabolites were analyzed using an SPE-800 MHz NMR-MS system. The metabolites were identified and quantified using a Chenomx NMR suite 8.4. Metabolic pathway analysis and principal component analysis were conducted using a Metaboanalyst 4.0. Statistical analysis was performed using a Dunnett's test on the SAS program. As a result, several metabolites were identified, and among them, 77 metabolites were used in statistical analysis. The levels of twelve metabolites were significantly higher in the HC group: succinate, dimethylamine, histamine, homovanillate, thymol, acetate, propionate, butyrate, isovalerate, valerate, imidazole, N-nitrosodimethylamine, and O-acetylcholine. In the HC group, the concentrations of all metabolites were higher than in the HR group, and the metabolic pathway was also different. This study is expected to be useful for a variety of livestock studies by 1H-NMR because it examined the change in metabolites in the body metabolism and microorganisms.

• Journal of Plant Biotechnology
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• v.37 no.1
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• pp.12-24
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• 2010

Plant metabolomics is a research field for identifying all of the metabolites found in a certain plant cell, tissue, organ, or whole plant in a given time and conditions and for studying changes in metabolic profiling as time goes or conditions change. Metabolomics is one of the most recently developed omics for holistic approach to biology and is a kind of systems biology. Metabolomics or metabolite fingerprinting techniques usually involves collecting spectra of crude solvent extracts without purification and separation of pure compounds or not in standardized conditions. Therefore, that requires a high degree of reproducibility, which can be achieved by using a standardized method for sample preparation and data acquisition and analysis. In plant biology, metabolomics is applied for various research fields including rapid discrimination between plant species, cultivar and GM plants, metabolic evaluation of commercial food stocks and medicinal herbs, understanding various physiological, stress responses, and determination of gene functions. Recently, plant metabolomics is applied for characterization of gene function often in combination with transcriptomics by analyzing tagged mutants of the model plants of Arabidopsis and rice. The use of plant metabolomics combined by transcriptomics in functional genomics will be the challenge for the coming year. This review paper attempted to introduce current status and prospects of plant metabolomics research.

• Korean Journal of Microbiology
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• v.49 no.2
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• pp.179-183
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• 2013

Marine-derived microbes have yielded a variety of metabolites so far. In the course of the project to find metabolites from marine microbes, an isolate of Aspergillus protuberus (SF 5767) was selected for chemical investigation. A large scale culture of this strain in PDA media was extracted with an organic solvent and the extract was fractionated by silica gel column chromatography. Repeated reverse phase HPLC of the fractions led to the isolation of three metabolites. Their chemical structures were elucidated as deoxybrevianamide E (1), brevianamide V (2), and ergosterol peroxide (3) on the basis of spectroscopic data including MS, NMR, and UV. To the best of our knowledge, chemical investigation of A. protuberus was conducted for the first time in this study.

• Analytical Science and Technology
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• v.20 no.4
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• pp.315-322
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• 2007

This study has been described the metabolism and excretion in a healthy male urine collected for 24 hr after oral administration of a complex (pseudoephedrine and dextromethorphan). To detect the trace amounts of parent drugs and their metabolites, acid-hydrolyzed urine was extracted and derivatized with MSTFA and MBTFA followed by gas chromatography/mass spectrometric analysis. Two parent drugs and their metabolites were tentatively identified as their derivatives based on the mass spectral interpretation and compared with previous reports. In addition, the time profile of urinary excretion rate for parent drugs and metabolites was studied. On the basis of metabolites identified and excretion rate, the metabolic pathways of both drugs are suggested.

• Journal of Life Science
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• v.21 no.2
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• pp.316-321
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• 2011

Generation of tryptophan-derived metabolites by indoleamine 2,3-dioxygenase (IDO) is a potent immunoregulatory mechanism in T cell responses. However, the mechanism remains unclear. We showed that 3-hydroxyanthranilic acid (3-HAA), the most potent metabolite, selectively induced apoptosis in activated T cells, but not in resting T cells. This was not associated with cell cycle arrest. We found that TRAIL expression was selectively induced in activated T cells by treatment of 3-HAA. Blockade of the TRAIL: DR4/DR5 pathway significantly inhibited 3-HAA-mediated T cell death. Our data suggest that TRAIL-induced apoptosis is involved in the mechanism of 3-HAA-mediated T cell death.

• Analytical Science and Technology
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• v.17 no.4
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• pp.322-336
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• 2004

The improved derivatization technique of tamoxifen metabolite in human urine is described for the acylation method that they are substituted by derivatization reagent like acyl anhydride for use of gas chromatography/mass spectrometry. The hydroxyl group of tamoxifen metabolite was derivatized by trifluoroacetic anhydride (TFAA), pentafluoroacetic anhydride (PFPA) and heptaflorobutylic anhydride (HFBA). It was investigated to the gas chromatography/mass spectrometry (GC/MS) technique use negative ion chemical ionization (NCI), positive ion chemical ionization (PCI) and electron impact (EI). In acylation of the metabolites of tamoxifen, the effective reaction temperature and time were shown to be at $50^{\circ}C$ for 30 min. The 4-hydroxytamoxifen, which is known to major metabolite of tamoxifen, was not detected in human urine, whileas the hydroxymethoxytamoxifen was detected. We thought that this result was from the single dose of tamoxifen.

• Analytical Science and Technology
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• v.23 no.2
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• pp.179-186
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• 2010

The oxidative metabolism of ibuprofen in healthy male urine collected at 3, 6, 9, 12 and 15 h after oral administration of ibuprofen was studied by GC/MS assay. To detect conjugated metabolites of ibuprofen, urine sample was acid-hydrolyzed with 6 M HCl at $100^{\circ}C$ for 30 min. To effectively extract ibuprofen and its metabolites, liquid-liquid extraction (LLE) was conducted at pH 3, 5, and 7, respectively. As a result, LLE at pH 3 was shown to be the best extraction condition. For the determination of trace amounts of ibuprofen and its metabolites in extract, trimethylsilylation (TMS) with BSTFA was applied and followed by GC/MS analysis. In this study, main 5 metabolites including parent drug were detected and these metabolites were assigned as three hydroxylated forms and one carboxylated form. Each metabolite was tentatively identified by both interpretation of mass spectrum and comparison with previously reported results. In addition, time profile of urinary excretion rate for parent drugs and metabolites was studied. Finally, the metabolic pathways of ibuprofen were suggested on the basis of the structural elucidation of its metabolites and excretion profiles.

• The Korean Journal of Pharmacology
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• v.28 no.1
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• pp.11-18
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• 1992

Rats were treated with physostigmine, using 0.75 mg/kg acutely, with 0.75 mg/kg daily for 7 dats, or with 0.15 mg/kg/h continuously for 7 days. Striatal dopamine (DA), dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) levels and tyrosine hydroxylase (TH) activities were studied. After acute treatment striatal DOPAC and HVA concentrations were significantly increased without changes in DA level 1 h, but not 24 h. And also the ratios of DOPAC/DA and HVA/DA were increased, suggesting an increased turnover of DA. however TH activities were decreased 24h, but not 1h after acute administration. After both daily and continuous treatment with physostigmine for 7 days, neither DA nor its metabolites were changed. However their ratios were decreased, suggesting a decreased turnover of DA. The TH activities were only decreased in the daily treated group, but not in the continously treated one. These results indicate that dopamine metabolisms are changed after acute and subacute administration with physostigmine. Further it suggest that the subacute stimulation of cholinergic activity may induce the dopamine metablism and activity to be decreased.

• Horticultural Science & Technology
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• v.34 no.2
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• pp.324-330
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• 2016

To determine whether FT-IR spectral analysis based on multivariate analysis for whole cell extracts can be used to discriminate between artichoke (Cynara cardunculus var. scolymus L.) plants at the metabolic level, leaves of ten artichoke plants were subjected to Fourier transform infrared(FT-IR) spectroscopy. FT-IR spectral data from leaves were analyzed by principal component analysis (PCA), partial least square discriminant analysis (PLS-DA) and hierarchical clustering analysis (HCA). FT-IR spectra confirmed typical spectral differences between the frequency regions of 1,700-1,500, 1,500-1,300 and $1,100-950cm^{-1}$, respectively. These spectral regions reflect the quantitative and qualitative variations of amide I, II from amino acids and proteins ($1,700-1,500cm^{-1}$), phosphodiester groups from nucleic acid and phospholipid ($1,500-1,300cm^{-1}$) and carbohydrate compounds ($1,100-950cm^{-1}$). PCA revealed separate clusters that corresponded to their species relationship. Thus, PCA could be used to distinguish between artichoke species with different metabolite contents. PLS-DA showed similar species classification of artichoke. Furthermore these metabolic discrimination systems could be used for the rapid selection and classification of useful artichoke cultivars.