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You searched for: Subject term liquid chromatography Remove constraint Subject term: liquid chromatography Subject term hydroxylation Remove constraint Subject term: hydroxylation Text availability Citation in PubAg Remove constraint Text availability: Citation in PubAg
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1. Use of liquid chromatography quadrupole time-of-flight mass spectrometry in the elucidation of transformation products and metabolites of pesticides. Diazinon as a case study

Author:
Ibáñez, María; Sancho, Juan V.; Pozo, Óscar J.; Hernández, Félix
Source:
Analytical and bioanalytical chemistry 2006 v.384 no.2 pp. 448-457
ISSN:
1618-2642
Subject:
aromatic compounds; case studies; centrifugation; diazinon; hydrolysis; hydroxylation; in vivo studies; ionization; liquid chromatography; mass spectrometry; mercury; metabolism; metabolites; oxidation; photolysis; polar compounds; sulfur; thiophosphate
Abstract:
... Liquid chromatography (LC) coupled to hybrid quadrupole time-of-flight (QTOF) mass spectrometry (MS) is a useful analytical tool in the elucidation and confirmation of transformation products (TPs)/metabolites of pesticides with a wide range of polarity, in both environmental and biological samples. Firstly, the versatility of LC allows the determination of very distinct TPs/metabolites as chromat ...
DOI:
10.1007/s00216-005-0167-6
PubMed:
16320041

2. Cytochrome P450 (CYP105F2) from Streptomyces peucetius and its activity with oleandomycin

Author:
Pramod Shrestha; Tae-Jin Oh; Kwangkyong Liou; Jae Kyung Sohng
Source:
Applied microbiology and biotechnology 2008 v.79 no.4 pp. 555
ISSN:
0175-7598
Subject:
Escherichia coli; Streptomyces peucetius; aerobiosis; cytochrome P-450; genes; hydroxylation; liquid chromatography; mass spectrometry; models; oleandomycin; substrate specificity
Abstract:
... The cytochrome P450 enzyme is one of the most versatile redox proteins and it is responsible for the oxidative metabolism of a wide variety of endogenous and exogenous compounds. The cytochrome P450 gene, CYP105F2, from Streptomyces peucetius was subcloned into the pET-32a(+) vector to overexpress the protein in E. coli BL21 (DE3) pLysS. The expressed enzyme was purified by fast protein liquid chr ...
DOI:
10.1007/s00253-008-1455-9
PubMed:
18437375

3. Metabolic studies of tetrazepam based on electrochemical simulation in comparison to in vivo and in vitro methods

Author:
Baumann, Anne; Lohmann, Wiebke; Schubert, Birthe; Oberacher, Herbert; Karst, Uwe
Source:
Journal of chromatography 2009 v.1216 no.15 pp. 3192-3198
ISSN:
0021-9673
Subject:
alkanes; alkenes; biochemical pathways; carbon; diazepam; electrochemistry; electrodes; hydroxylation; in vivo studies; liquid chromatography; mass spectrometry; metabolic studies; metabolism; metabolites; muscles; oxidation; patients; prediction; screening; urine
Abstract:
... During the last 2 years, the knowledge on the metabolic pathway of tetrazepam, a muscle relaxant drug, was expanded by the fact that diazepam was identified as a degradation product of tetrazepam. The present study demonstrates that this metabolic conversion, recently discovered by in vivo studies, can also be predicted on the basis of a purely instrumental method, consisting of an electrochemical ...
DOI:
10.1016/j.chroma.2009.02.001

4. Studies on the metabolism of the Δ9-tetrahydrocannabinol precursor Δ9-tetrahydrocannabinolic acid A (Δ9-THCA-A) in rat using LC-MS/MS, LC-QTOF MS and GC-MS techniques

Author:
Jung, Julia; Meyer, Markus R.; Maurer, Hans H.; Neusüß, Christian; Weinmann, Wolfgang; Auwärter, Volker
Source:
Journal of mass spectrometry 2009 v.44 no.10 pp. 1423-1433
ISSN:
1076-5174
Subject:
Cannabis sativa; animal models; blood serum; extracts; gas chromatography-mass spectrometry; hydroxylation; liquid chromatography; metabolism; metabolites; rats; sampling; tandem mass spectrometry; urine
Abstract:
... In Cannabis sativa, Δ9-Tetrahydrocannabinolic acid-A (Δ9-THCA-A) is the non-psychoactive precursor of Δ9-tetrahydrocannabinol (Δ9-THC). In fresh plant material, about 90% of the total Δ9-THC is available as Δ9-THCA-A. When heated (smoked or baked), Δ9-THCA-A is only partially converted to Δ9-THC and therefore, Δ9-THCA-A can be detected in serum and urine of cannabis consumers. The aim of the prese ...
DOI:
10.1002/jms.1624

5. Fate of antibacterial spiramycin in river waters

Author:
Calza, P.; Marchisio, S.; Medana, C.; Baiocchi, C.
Source:
Analytical and bioanalytical chemistry 2010 v.396 no.4 pp. 1539-1550
ISSN:
1618-2642
Subject:
Vibrio fischeri; drugs; environmental fate; hydroxylation; laboratory experimentation; lighting; liquid chromatography; mass spectrometry; mineralization; photolysis; river water; spiramycin; sugars; toxicity
Abstract:
... Spiramycin, a widely used veterinary macrolide antibiotic, was found at traceable levels (nanograms per litre range) in Po River water (N-Italy). The aqueous environmental fate of this antibiotic compound was studied through drug decomposition, the identification of the main and secondary transformation products (TPs), assessment of mineralisation and the investigation of drug TPs toxicity. Initia ...
DOI:
10.1007/s00216-009-3318-3
PubMed:
19960340

6. Oxidative cascade reactions yielding polyhydroxy-theaflavins and theacitrins in the formation of black tea thearubigins: Evidence by tandem LC-MS

Author:
Nikolai Kuhnert; Michael N. Clifford; Anja Müller
Source:
Food & function 2010 v.1 no.2 pp. 180-199
ISSN:
2042-650X
Subject:
black tea; catechin; dicarboxylic acids; glycols; hydroxylation; liquid chromatography; mass spectrometry; oxygen; quinones; theaflavins
Abstract:
... LC-MSⁿ and direct infusion-MSⁿ have been applied for the first time to the characterisation of crude thearubigins isolated from black tea. The data generated have been used to test two hypotheses of thearubigin structure: (i) that a significant fraction of the thearubigins consist of polyhydroxylated derivatives of the better-known catechin dimers (theaflavins, theaflavin mono- and di-gallates, th ...
DOI:
10.1039/c0fo00066c

7. Studies on the metabolism of the α‐pyrrolidinophenone designer drug methylenedioxy‐pyrovalerone (MDPV) in rat and human urine and human liver microsomes using GC-MS and LC-high‐resolution MS and its detectability in urine by GC-MS

Author:
Meyer, Markus R.; Du, Peng; Schuster, Frank; Maurer, Hans H.
Source:
Journal of mass spectrometry 2010 v.45 no.12 pp. 1426-1442
ISSN:
1076-5174
Subject:
forensic sciences; gas chromatography-mass spectrometry; humans; hydroxylation; illicit drugs; isozymes; liquid chromatography; liver microsomes; markets; metabolism; metabolites; methylation; oxidation; rats; sampling; toxicology; urine; Asia; Germany
Abstract:
... Since the late 1990s, many derivatives of the α‐pyrrolidinophenone (PPP) drug class appeared on the drugs of abuse market. The latest compound was described in 2009 to be a classic PPP carrying a methylenedioxy moiety remembering the classic entactogens (ecstasy). Besides Germany, 3,4‐methylene‐dioxypyrovalerone (MDPV) has appeared in many countries in Europe and Asia, indicating its worldwide imp ...
DOI:
10.1002/jms.1859

8. In vitro metabolic stability and metabolite profiling of TJ0711 hydrochloride, a newly developed vasodilatory β-blocker, using a liquid chromatography–tandem mass spectrometry method

Author:
Jiangeng Huang; Luqin Si; Zhaoze Fan; Lei Hu; Jun Qiu; Gao Li
Source:
Journal of chromatography 2011 v.879 no.30 pp. 3386-3392
ISSN:
1570-0232
Subject:
beta-adrenergic antagonists; detection limit; humans; hydrochloric acid; hydroxylation; ions; liquid chromatography; liver microsomes; metabolism; metabolites; monitoring; quantitative analysis; surveys; tandem mass spectrometry
Abstract:
... In this paper, a liquid chromatography–tandem mass spectrometry (LC–MS/MS) method was developed and validated for the simultaneous analysis of metabolic stability and metabolite profiling of 1-[4-(2-methoxyethyl) phenoxy]-3-[[2-(2-methoxyphenoxy) ethyl]amino]-2-propanol hydrochloride (TJ0711 HCl), a new vasodilatory β-blocker. Multiple reaction monitoring (MRM) was used as a survey scan to quantif ...
DOI:
10.1016/j.jchromb.2011.09.010

9. LC-MS-MS determination of ibuprofen, 2-hydroxyibuprofen enantiomers, and carboxyibuprofen stereoisomers for application in biotransformation studies employing endophytic fungi

Author:
Borges, Keyller Bastos; de Oliveira, Anderson Rodrigo Moraes; Barth, Thiago; Jabor, Valquíria Aparecida Polizel; Pupo, Mônica Tallarico; Bonato, Pierina Sueli
Source:
Analytical and bioanalytical chemistry 2011 v.399 no.2 pp. 915-925
ISSN:
1618-2642
Subject:
Chaetomium globosum; Nigrospora; acetates; ambient temperature; ammonium acetate; biotransformation; culture media; enantiomers; endophytes; freeze-thaw cycles; fungi; hydroxylation; ibuprofen; ionization; liquid chromatography; liquid-liquid extraction; metabolites; methanol; oxidation; particle size; solvents; tandem mass spectrometry
Abstract:
... The purpose of this study was the development and validation of an LC-MS-MS method for simultaneous analysis of ibuprofen (IBP), 2-hydroxyibuprofen (2-OH-IBP) enantiomers, and carboxyibuprofen (COOH-IBP) stereoisomers in fungi culture medium, to investigate the ability of some endophytic fungi to biotransform the chiral drug IBP into its metabolites. Resolution of IBP and the stereoisomers of its ...
DOI:
10.1007/s00216-010-4329-9

10. Mechanistic studies of photoinduced degradation of Orange G using LC/MS

Author:
M. A. Meetani; M. A. Rauf; S. Hisaindee; A. Khaleel; A. AlZamly; A. Ahmad
Source:
RSC advances 2011 v.1 no.3 pp. 490-497
ISSN:
2046-2069
Subject:
aromatic amines; catalysts; chromic oxide; dyes; hydroxylation; liquid chromatography; mass spectrometry; pH; phenols; photocatalysis; titanium dioxide; ultraviolet radiation
Abstract:
... Photocatalytic degradation of Orange G dye was carried out with UV light in the presence of TiO₂ mixed with 20% chromium oxide as a catalyst. The conditions for maximum dye degradation were optimized in terms of catalyst amount, dye concentration, pH and time. The dye degradation followed pseudo first-order kinetics. LC-MS/MS was used to track the numerous intermediate products formed during the c ...
DOI:
10.1039/c1ra00177a

11. Photocatalytic degradation of benzenesulfonate on colloidal titanium dioxide

Author:
Erzsébet Szabó-Bárdos; Otília Markovics; Ottó Horváth; Norbert Törő; Gyula Kiss
Source:
Water research 2011 v.45 no.4 pp. 1617-1628
ISSN:
0043-1354
Subject:
absorption; aldehydes; carbon; carboxylic acids; chemical oxygen demand; dissolved oxygen; hydroxyl radicals; hydroxylation; irradiation; liquid chromatography; mass spectrometry; mineralization; monitoring; pH; photolysis; protons; surfactants; titanium; titanium dioxide
Abstract:
... Titanium dioxide-mediated photocatalyzed degradation of benzenesulfonate (BS) was investigated by monitoring chemical oxygen demand (COD), total organic carbon (TOC) content, sulfate concentration, pH as well as the absorption and emission spectral changes in both argon-saturated and aerated systems. Liquid chromatography-mass spectrometry analysis was utilized for the detection of intermediates f ...
DOI:
10.1016/j.watres.2010.11.045
PubMed:
21185053

12. Transformation of Bisphenol A in the Presence of Manganese Dioxide

Author:
Na Gao; Jianwen Hong; Zhiqiang Yu; Ping' Peng; Weilin Huang
Source:
Soil science 2011 v.176 no.6 pp. 265-272
ISSN:
0038-075X
Subject:
active sites; adsorption; batch systems; bisphenol A; dealkylation; electrolytes; gas chromatography-mass spectrometry; hydroxylation; ionic strength; liquid chromatography; manganese; manganese dioxide; oxidation; pH; reaction mechanisms; soil; tandem mass spectrometry; zinc
Abstract:
... This study investigates the abiotic transformation of bisphenol A (BPA) in the presence of manganese dioxide (MnO2) and under a spectrum of solution chemistry conditions using batch reactor systems. The results indicated that, at a fixed MnO2 concentration, the reaction rate decreased as a function of initial BPA concentration, and that at a fixed initial BPA concentration, the rate increased as a ...
DOI:
10.1097/SS.0b013e31821d0b97

13. Characterization and estimation of sulfaquinoxaline metabolites in animal tissues using liquid chromatography coupled to tandem mass spectrometry

Author:
Rodrigo Barcellos Hoff; Fabiano Barreto; Jéssica Melo; Louise Jank; Maria do Carmo Ruaro Peralba; Tânia Mara Pizzolato
Source:
Analytical methods 2012 v.4 no.9 pp. 2822-2830
ISSN:
1759-9679
Subject:
animal tissues; beef; drugs; food matrix; horse meat; hydroxylation; ions; kidneys; liquid chromatography; liver; maximum residue limits; metabolism; metabolites; muscles; pork; poultry meat; solvents; sulfaquinoxaline; tandem mass spectrometry; temperature; veterinary medicine; Brazil
Abstract:
... Sulfaquinoxaline (SQX) is a sulfonamide that is widely used in veterinary medicine, with a maximum residue limit (MRL) established for several food matrices. In Brazil, the MRL for liver and muscle is 100 μg kg⁻¹ for equine, bovine, poultry and swine. This value includes not only free drug but also the sum of all metabolites. Several reports showed limitations for SQX residue analysis, especially ...
DOI:
10.1039/c2ay25197c

14. Characterization of Bisphenol A Metabolites Produced by Portulaca oleracea cv. by Liquid Chromatography Coupled with Tandem Mass Spectrometry

Author:
Ippei WATANABE; Kazuo HARADA; Takeshi MATSUI; Hitoshi MIYASAKA; Hiroshi OKUHATA; Satoshi TANAKA; Hideki NAKAYAMA; Ko KATO; Takeshi BAMBA; Kazumasa HIRATA
Source:
Bioscience, biotechnology, and biochemistry 2012 v.76 no.5 pp. 1015-1017
ISSN:
1347-6947
Subject:
Portulaca oleracea; biotechnology; bisphenol A; endocrine-disrupting chemicals; hydroponics; hydroxylation; liquid chromatography; metabolism; metabolites; ornamental plants; oxidoreductases; polyphenols; quinones; tandem mass spectrometry
Abstract:
... The garden plant portulaca (Portulaca oleracea cv.) efficiently removes bisphenol A (BPA), an endocrine-disrupting chemical, from a hydroponic solution, but the molecular mechanisms underlying BPA metabolism by portulaca remain unclear. In this study, BPA metabolites converted by portulaca were analyzed by liquid chromatography coupled with tandem mass spectrometry. We observed the hydroxylation o ...
DOI:
10.1271/bbb.110967

15. Identification of metabolites of Si-Ni-San, a traditional Chinese medicine formula, in rat plasma and urine using liquid chromatography/diode array detection/triple–quadrupole spectrometry

Author:
Zhixiang Yan; Ying Chen; Tianxue Li; Jie Zhang; Xinghao Yang
Source:
Journal of chromatography 2012 v.885-886 no. pp. 73-82
ISSN:
1570-0232
Subject:
Oriental traditional medicine; biochemical pathways; computer software; flavanones; gallic acid; hydroxylation; liquid chromatography; metabolism; metabolites; methylation; prediction; rats; spectroscopy; triterpenoid saponins; urine
Abstract:
... Si-Ni-San (SNS) is a widely used traditional Chinese medicine formula (TCMF) in treating various diseases. However, the in vivo integrated metabolism of its multiple components remains unknown. In this paper, a liquid chromatography coupled with diode array detection and triple–quadrupole spectrometry (LC-DAD–MS/MS) method was developed for detection and identification of SNS metabolites in rat pl ...
DOI:
10.1016/j.jchromb.2011.12.017

16. In vitro enantioselective metabolism of TJ0711 hydrochloride by human liver microsomes using a novel chiral liquid chromatography–tandem mass spectrometry method

Author:
Jiangeng Huang; Lei Hu; Li Xu; Minghui Sun; Zhaoze Fan; Jun Qiu; Gao Li; Luqin Si
Source:
Journal of chromatography 2012 v.891-892 no. pp. 98-101
ISSN:
1570-0232
Subject:
beta-adrenergic antagonists; enantiomers; ethanol; hexane; humans; hydrochloric acid; hydroxylation; liquid chromatography; liver microsomes; metabolism; metabolites; tandem mass spectrometry
Abstract:
... A novel liquid chromatography–tandem mass spectrometry (LC–MS/MS) method employing chiral analytical techniques was developed and validated for in vitro enantioselective metabolic stability study of racemic 1-[4-(2-methoxyethyl) phenoxy]-3-[[2-(2-methoxyphenoxy) ethyl]amino]-2-propanol hydrochloride (TJ0711 HCl), a newly developed vasodilatory β-blocker. Robust enantiomeric separations were achiev ...
DOI:
10.1016/j.jchromb.2012.02.018

17. Paracetamol degradation intermediates and toxicity during photo-Fenton treatment using different iron species

Author:
Alam G. Trovó; Raquel F. Pupo Nogueira; Ana Agüera; Amadeo R. Fernandez-Alba; Sixto Malato
Source:
Water research 2012 v.46 no.16 pp. 5374-5380
ISSN:
0043-1354
Subject:
nitrogen content; Vibrio fischeri; iron; ammonium compounds; carbon; nitrates; ferrous sulfate; toxicity; hydroxylation; mass spectrometry; liquid chromatography; carboxylic acids; Daphnia magna
Abstract:
... The photo-Fenton degradation of paracetamol (PCT) was evaluated using FeSO₄ and the iron complex potassium ferrioxalate (FeOx) as iron source under simulated solar light. The efficiency of the degradation process was evaluated considering the decay of PCT and total organic carbon concentration and the generation of carboxylic acids, ammonium and nitrate, expressed as total nitrogen. The results sh ...
DOI:
10.1016/j.watres.2012.07.015
PubMed:
22863025

18. Prolyl hydroxylase domain protein 2 regulates the intracellular cyclic AMP level in cardiomyocytes through its interaction with phosphodiesterase 4D

Author:
Zhaoxia Huo; Jiang-Chuan Ye; Jinjin Chen; Xiaoping Lin; Zhao-Nian Zhou; Xin-Ran Xu; Chang-Ming Li; Man Qi; Dandan Liang; Yi Liu; Jun Li
Source:
Biochemical and biophysical research communications 2012 v.427 no.1 pp. 73-79
ISSN:
0006-291X
Subject:
adenosine monophosphate; adenylate cyclase; cardiomyocytes; cyclic AMP; gene overexpression; genes; hydroxylation; liquid chromatography; oxygen; procollagen-proline dioxygenase; protein synthesis; proteins; rats; signal transduction; tandem mass spectrometry
Abstract:
... Cyclic adenosine 3’,5’-monophosphate (cAMP), which is synthesized by adenylyl cyclase (AC) and degraded by phosphodiesterase (PDE), plays crucial roles in the regulation of multiple cellular functions and physiological processes. Prolyl hydroxylase domain (PHD) proteins, which belong to a family of dioxygenases that function as oxygen sensors through their hydroxylation activity, have been implica ...
DOI:
10.1016/j.bbrc.2012.09.005

19. Screening and identification of BSA bound ligands from Puerariae lobata flower by BSA functionalized Fe₃O₄ magnetic nanoparticles coupled with HPLC–MS/MS

Author:
Liangliang Liu; Yongjian Ma; Xiaoqing Chen; Xiang Xiong; Shuyun Shi
Source:
Journal of chromatography 2012 v.887-888 no. pp. 55-60
ISSN:
1570-0232
Subject:
Pueraria montana var. lobata; binding capacity; biochanin A; bovine serum albumin; chemical structure; daidzein; daidzin; flowers; hydroxylation; iron oxides; ligands; liquid chromatography; nanoparticles; poisoning; rapid methods; screening; tandem mass spectrometry; China
Abstract:
... Puerariae lobata flower (Willdenow) has a long history used to treat alcoholic intoxication in China, which contains a series of isoflavones as its chief pharmacologically active constituents. In this study, bovine serum albumin (BSA) functionalized iron oxide magnetic nanoparticles (Fe₃O₄ MNPs) coupled with high performance liquid chromatography–tandem mass spectrometry (HPLC–MS/MS) were used to ...
DOI:
10.1016/j.jchromb.2012.01.008

20. A new method for identification of in vitro metabolites of 2,3,7,8-TCDD with rat liver microsomes by using liquid chromatography-mass spectrometry

Author:
Chunyan Wang; Zhi Tang; Yanling Zhang; Yan Liang; Fengrui Song; Zongwei Cai
Source:
Analytical methods 2013 v.5 no.11 pp. 2757-2760
ISSN:
1759-9679
Subject:
animal and human health; environmental fate; gas chromatography-mass spectrometry; hydroxylation; liquid chromatography; liver microsomes; metabolism; metabolites; persistent organic pollutants; rats; tandem mass spectrometry; tetrachlorodibenzo-p-dioxin; toxicity
Abstract:
... 2,3,7,8-Tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) is known as a highly toxic environmental contaminant and poses potential risks to human and animal health. As a persistent organic pollutant, 2,3,7,8-TCDD is hard to metabolize and thus gets accumulated in the human and animal body. Literature reports on the metabolism study of 2,3,7,8-TCDD are rare. The traditional method of GC-MS for 2,3,7,8-TCD ...
DOI:
10.1039/c3ay26443b

21. Acebutolol and alprenolol metabolism predictions: comparative study of electrochemical and cytochrome P450-catalyzed reactions using liquid chromatography coupled to high-resolution mass spectrometry

Author:
Ugo Bussy; Marcel Delaforge; Chaimaâ El-Bekkali; Véronique Ferchaud-Roucher; Michel Krempf; Illa Tea; Nicolas Galland; Denis Jacquemin; Mohammed Boujtita
Source:
Analytical and bioanalytical chemistry 2013 v.405 no.18 pp. 6077-6085
ISSN:
1618-2642
Subject:
biotransformation; cytochrome P-450; electrochemistry; hydroxylation; liquid chromatography; liver microsomes; mass spectrometry; metabolism; oxidation; prediction; rats
Abstract:
... A comparative study of the electrochemical conversion and the biotransformation performed by the cytochrome P450 (CYP450) obtained by rat liver microsomes has been achieved to elucidate the oxidation mechanism of both acebutolol and alprenolol. For this purpose, a wide range of reactions such as N-dealkylation, O-dealkoxylation, aromatic hydroxylation, benzyl hydroxylation, alkyl hydroxylation, an ...
DOI:
10.1007/s00216-013-7050-7

22. Assessment of silicone as support to investigate the transformation routes of organic chemicals under environmental conditions and UV exposure. Application to selected fungicides

Author:
T. Rodríguez-Cabo; I. Rodríguez; M. Ramil; R. Cela
Source:
Analytical and bioanalytical chemistry 2013 v.405 no.12 pp. 4187-4198
ISSN:
1618-2642
Subject:
acetonitrile; arsenic; autumn; byproducts; chemical degradation; desorption; difenoconazole; environmental factors; fenhexamid; half life; hydroxylation; leaves; liquid chromatography; mass spectrometry; mercury; silicone; soil; summer; triadimenol; ultraviolet radiation; vegetables
Abstract:
... The suitability of bulk silicone as support to follow the degradation of chemical compounds under environmental conditions and UV radiation is illustrated selecting three fungicides (fenhexamid, FEN; triadimenol, TRI and difenoconazole, DIF) as model compounds. These precursor species were first absorbed in silicone supports (10 mm length × 2 mm i.d. and 0.5 mm thickness) and then kept outdoors fo ...
DOI:
10.1007/s00216-013-6821-5

23. Characterization of oxidized phospholipids in oxidatively modified low density lipoproteins by nanoflow liquid chromatography–tandem mass spectrometry

Author:
Ju Yong Lee; Sangsoo Lim; Sungha Park; Myeong Hee Moon
Source:
Journal of chromatography 2013 v.1288 no. pp. 54-62
ISSN:
0021-9673
Subject:
atherosclerosis; blood; copper; hydroxylation; liquid chromatography; low density lipoprotein; oxidation; phospholipids; tandem mass spectrometry
Abstract:
... Oxidized low density lipoproteins (Ox-LDLs) have an important role in the development of age-related vascular disease, such as atherosclerosis. Ox-LDLs are defined as oxidatively modified LDLs in the blood by enzymatic or non-enzymatic oxidation of phospholipids (PLs). For the characterization of Ox-LDLs at molecular level, oxidation patterns of oxidized PL (Ox-PL) products were systematically exa ...
DOI:
10.1016/j.chroma.2013.02.086

24. Characterization of the biotransformation pathways of clomiphene, tamoxifen and toremifene as assessed by LC-MS/(MS) following in vitro and excretion studies

Author:
Monica Mazzarino; Mariangela Biava; Xavier de la Torre; Ilaria Fiacco; Francesco Botrè
Source:
Analytical and bioanalytical chemistry 2013 v.405 no.16 pp. 5467-5487
ISSN:
1618-2642
Subject:
biotransformation; carboxylation; citrates; cytochrome P-450; dehalogenation; enzymes; estrogen receptors; excretion; females; hydrogenation; hydroxylation; in vitro studies; isozymes; liquid chromatography; males; mass spectrometry; metabolism; metabolites; oral administration; tamoxifen; uridine; urine
Abstract:
... The use of selective oestrogen receptor modulators has been prohibited since 2005 by the World Anti-Doping Agency regulations. As they are extensively cleared by hepatic and intestinal metabolism via oxidative and conjugating enzymes, a complete investigation of their biotransformation pathways and kinetics of excretion is essential for the anti-doping laboratories to select the right marker(s) of ...
DOI:
10.1007/s00216-013-6961-7

25. Chromatography and High-Resolution Mass Spectrometry for the Characterization of the Degradation Products of the Photodegradation of Amidosulfuron: An Analytical Approach

Author:
Harir Mourad; Chnirheb Amina; Kanawati Basem; El Azzouzi Mohammed; Schmitt-Kopplin Philippe
Source:
Journal of agricultural and food chemistry 2013 v.61 no.22 pp. 5271-5278
ISSN:
1520-5118
Subject:
solar radiation; photolysis; sulfuric acid; herbicides; mass spectrometry; sulfonic acids; hydroxylation; irradiation; liquid chromatography
Abstract:
... Simulated sunlight irradiation causing degradation of amidosulfuron, a pyrimidinylsulfonylurea herbicide, has been investigated in aqueous solution. The main degradation products were followed up by ultrahigh-pressure liquid chromatography with a UV detector (UHPLC-UV) and identified by combining ultrahigh-pressure liquid chromatography–mass spectrometry (UHPLC-MS) and Fourier transform ion cyclot ...
DOI:
10.1021/jf400133w
PubMed:
23577633

26. In vitro metabolism of alisol A and its metabolites’ identification using high-performance liquid chromatography–mass spectrometry

Author:
Yue Yu; Zhenzhen Liu; Ping Ju; Yuanyuan Zhang; Lunhui Zhang; Kaishun Bi; Xiaohui Chen
Source:
Journal of Chromatography B 2013 v.941 pp. 31-37
ISSN:
1570-0232
Subject:
chemical inhibitors; cytochrome P-450; enzyme kinetics; humans; hydroxylation; isozymes; liquid chromatography; liver microsomes; mass spectrometry; metabolism; metabolites; rats
Abstract:
... A liquid chromatography–mass spectrometry (LC–MS) method was developed and successfully applied to the study on the enzyme kinetics of alisol A in rat liver microsomes (RLM) and human liver microsomes (HLM) incubation systems, and employed for semi-quantitative determination of each metabolite of alisol A. The metabolites of alisol A in RLM, HLM and human recombinant CYP3A4 enzyme incubation syste ...
DOI:
10.1016/j.jchromb.2013.09.029

27. Investigation of degradation products of cocaine and benzoylecgonine in the aquatic environment

Author:
Lubertus Bijlsma; Clara Boix; Wilfried M.A. Niessen; María Ibáñez; Juan V. Sancho; Félix Hernández
Source:
Science of the total environment 2013 v.443 pp. 200-208
ISSN:
0048-9697
Subject:
aquatic environment; chlorination; cocaine; hydrolysis; hydroxylation; ions; irradiation; liquid chromatography; metabolites; reference standards; sewage effluent; solar radiation; spectrometers; surface water; wastewater
Abstract:
... In this work, ultra-high-performance liquid chromatography (UHPLC) coupled to a hybrid quadrupole time-of-flight mass spectrometer (QTOF MS) has allowed the discovery and elucidation of degradation products of cocaine and its main metabolite benzoylecgonine (BE) in water. Spiked surface water was subjected to hydrolysis, chlorination and photo-degradation (both ultraviolet irradiation and simulate ...
DOI:
10.1016/j.scitotenv.2012.11.006
PubMed:
23186631

28. Metabolite Profiles of Epimedin B in Rats by Ultraperformance Liquid Chromatography/Quadrupole-Time-of-Flight Mass Spectrometry

Author:
Cui Li; Sun E; Zhang Zhenhai; Qian Qian; Tan Xiaobin; Xu Fengjuan; Jia Xiaobin
Source:
Journal of agricultural and food chemistry 2013 v.61 no.15 pp. 3589-3599
ISSN:
1520-5118
Subject:
bile; biochemical pathways; feces; glucuronic acid; glycosylation; hydrogenation; hydrolysis; hydroxylation; liquid chromatography; liver; mass spectrometry; metabolites; oral administration; rats; urine
Abstract:
... In this work, the metabolite profiles of epimedin B in rat feces, bile, urine, and plasma were qualitatively investigated, and the possible metabolic pathways of epimedin B were subsequently proposed. After oral administration of epimedin B at a single dose of 80 mg/kg, rat biological samples were collected and pretreated by protein precipitation. Then, these pretreated samples were injected into ...
DOI:
10.1021/jf304625x
PubMed:
23360129

29. Characterisation of the Metabolism of Pogostone In Vitro and In Vivo Using Liquid Chromatography with Mass Spectrometry

Author:
Yucui Li; Ziren Su; Shuhai Lin; Chuwen Li; Ya Zhao; Xiang Gao; Yongquan Lai; Xiaoli Wu; Hanzhi Wu; Zongwei Cai; Xiaoping Lai
Source:
Phytochemical analysis 2014 v.25 no.2 pp. 97-105
ISSN:
0958-0344
Subject:
Pogostemon cablin; biochemical pathways; essential oils; hydrolysis; hydroxylation; in vitro studies; in vivo studies; liquid chromatography; liver microsomes; mass spectrometry; metabolism; metabolites; oral administration; quality control; rats
Abstract:
... INTRODUCTION: Pogostone possesses potent anti‐bacterial and anti‐fungal activities and has been used for the quality control of essential oil of Pogostemon cablin. Pogostone is easily absorbed after oral administration but its metabolism in mammals remains elusive. OBJECTIVE: To investigate the metabolic profile of pogostone in vitro and in vivo. METHODS: High‐performance liquid chromatography cou ...
DOI:
10.1002/pca.2471
PubMed:
24605365

30. Co-metabolic transformation of the neonicotinoid insecticide imidacloprid by the new soil isolate Pseudoxanthomonas indica CGMCC 6648

Author:
Yuan Ma; Shan Zhai; Shi Yun Mao; Shi Lei Sun; Ying Wang; Zhong Hua Liu; Yi Jun Dai; Sheng Yuan
Source:
Journal of environmental science and health 2014 v.49 no.9 pp. 661-670
ISSN:
1532-4109
Subject:
Pseudoxanthomonas; bacteria; biodegradation; carbon; environmental health; genes; glucose; half life; imidacloprid; insecticidal properties; lactose; liquid chromatography; mass spectrometry; metabolites; nuclear magnetic resonance spectroscopy; olefin; pyruvic acid; ribosomal RNA; soil
Abstract:
... A new imidacloprid (IMI) degrading bacterium Z-9 (deposited number CGMCC 6648) was isolated and identified as Pseudoxanthomonas indica by 16S rRNA gene analysis. Two metabolites were identified as olefin and 5-hydroxy IMI by liquid chromatography-mass spectrometry and nuclear magnetic resonance analysis. P . indica CGMCC 6648 degraded 70.1% of IMI (1.22 mmol L ⁻¹) and formed 0.93 mmol L ⁻¹ 5-hydro ...
DOI:
10.1080/03601234.2014.922766

31. Comparison of tiletamine and zolazepam pharmacokinetics in tigers (Panthera tigris) and leopards (Panthera pardus): Do species differences account for adverse effects in tigers?

Author:
J.C.M. Lewis; P. Teale; G. Webber; J.W. Sear; P.M. Taylor
Source:
veterinary journal 2014 v.201 no.3 pp. 302-306
ISSN:
1090-0233
Subject:
Panthera pardus; Panthera tigris; adverse effects; anesthesia; etiology; hydroxylation; interspecific variation; liquid chromatography; mass spectrometry; metabolites; pharmacokinetics; tiletamine
Abstract:
... Serious post-operative neurological complications of unknown aetiology are reported in tigers after immobilisation using tiletamine and zolazepam. These complications may arise from the persistent effects of tiletamine or active metabolites of tiletamine or zolazepam. Concentrations of tiletamine, zolazepam and some metabolites were measured using high performance liquid chromatography–mass spectr ...
DOI:
10.1016/j.tvjl.2014.05.041

32. Fast liquid chromatographic–tandem mass spectrometric method using mixed-mode phase chromatography and solid phase extraction for the determination of 12 mono-hydroxylated brominated diphenyl ethers in human serum

Author:
Syrago-Styliani E. Petropoulou; Wendy Duong; Myrto Petreas; June-Soo Park
Source:
Journal of chromatography 2014 v.1356 pp. 138-147
ISSN:
0021-9673
Subject:
aerobiosis; blood serum; bromination; detection limit; enzymatic hydrolysis; humans; hydroxylation; liquid chromatography; mass spectrometry; mice; polybrominated diphenyl ethers; protocols; rats; solid phase extraction; statistical analysis
Abstract:
... Hydroxylated polybrominated diphenyl ethers (OH-PBDEs) are formed from the oxidative metabolism of polybrominated diphenyl ethers (PBDEs) in humans, rats and mice, but their quantitation in human blood and other matrices with liquid chromatography–mass spectrometric techniques has been a challenge. In this study, a novel analytical method was developed and validated using only 250μL of human serum ...
DOI:
10.1016/j.chroma.2014.06.048

33. Identification of Metabolites and Thermal Transformation Products of Quinolones in Raw Cow’s Milk by Liquid Chromatography Coupled to High-Resolution Mass Spectrometry

Author:
Alexandra Junza; Sergio Barbosa; M. Rosa; Anna Jubert; Jose Barbosa; Dolores Barron
Source:
Journal of agricultural and food chemistry 2014 v.62 no.8 pp. 2008-2021
ISSN:
0021-8561
Subject:
antibiotics; ciprofloxacin; cows; difloxacin; enrofloxacin; heat treatment; hydroxylation; isomers; liquid chromatography; mass spectrometry; metabolites; microorganisms; milk; risk; sarafloxacin
Abstract:
... The presence of residues of antibiotics, metabolites, and thermal transformation products (TPs), produced during thermal treatment to eliminate pathogenic microorganisms in milk, could represent a risk for people. Cow’s milk samples spiked with enrofloxacin (ENR), ciprofloxacin (CIP), difloxacin (DIF), and sarafloxacin (SAR) and milk samples from cows medicated with ENR were submitted to several ...
DOI:
10.1021/jf405554z

34. Identification of intermediates and ecotoxicity assessment during the UV/H2O2 oxidation of azo dye Reactive Orange 16

Author:
Jelena Z. Mitrović; Miljana D. Radović; Tatjana D. Anđelković; Danijela V. Bojić; Aleksandar Lj. Bojić
Source:
Journal of environmental science and health 2014 v.49 no.5 pp. 491-502
ISSN:
1532-4117
Subject:
Vibrio; aquatic organisms; azo dyes; ecotoxicology; environmental health; hydroxylation; lamps; liquid chromatography; mercury; naphthalene; oxidation; tandem mass spectrometry; toxicity; toxicity testing; ultraviolet radiation
Abstract:
... Degradation of azo dye Reactive Orange 16, a widely used textile dye, was carried out with UV light in the presence of H ₂O ₂. The experiments were conducted in the batch mode using low-pressure mercury lamps, emitting at 253.7 nm. Liquid-chromatography tandem mass spectrometry (LC/MS/MS) and high resolution mass spectrometry (FT-ICR) were employed in order to identify some of degradation products ...
DOI:
10.1080/10934529.2014.859022

35. Investigation of liquid chromatography quadrupole time-of-flight mass spectrometry performance for identification and determination of hydroxylated stilbene antioxidants in wine

Author:
T. Rodríguez-Cabo; I. Rodríguez; P. López; M. Ramil; R. Cela
Source:
Journal of chromatography 2014 v.1337 pp. 162-170
ISSN:
0021-9673
Subject:
antioxidants; glycosylation; hydroxylation; liquid chromatography; mass spectrometry; methanol; red wines; resveratrol; solid phase extraction; white wines
Abstract:
... The performance of liquid chromatography (LC) followed by quadrupole time-of-flight (QTOF) mass spectrometry (MS) for the determination of hydroxylated stilbene compounds in red and white wine samples is assessed. When combined with a solid-phase extraction step, LC–QTOF-MS allowed the selective determination of five target compounds (trans- and cis-resveratrol, trans-piceatannol, trans-piceid and ...
DOI:
10.1016/j.chroma.2014.02.058

36. Metabolism of Mequindox in Isolated Rat Liver Cells

Author:
Guang-hui LI; Qi SHAN; Jing WANG; Ya-fei LI; Yan GAO; Zhen-ling ZENG
Source:
Journal of integrative agriculture 2014 v.13 no.1 pp. 158-166
ISSN:
2095-3119
Subject:
anti-infective agents; biochemical pathways; feed additives; hepatocytes; hydroxylation; ionization; ions; liquid chromatography; mass spectrometry; metabolism; metabolites; microsomes; rats; toxicity; veterinary medicine
Abstract:
... Mequindox (MEQ), 3-methyl-2-quinoxalinacetyl-1,4-dioxide, is widely used in Chinese veterinary medicine as an antimicrobial agent and feed additive. Its toxicity has been reported to be closely related to its metabolism. To understand the pathways underlying MEQ's metabolism more clearly, we studied its metabolism in isolated rat liver cells by using liquid chromatography coupled with electrospray ...
DOI:
10.1016/S2095-3119(13)60335-4

37. Noctilisin, a Venom Glycopeptide of Sirex noctilio (Hymenoptera: Siricidae), Causes Needle Wilt and Defense Gene Responses in Pines

Author:
Bordeaux J. Michael; Lorenz W. Walter; Johnson Darryl; Badgett Majors J.; Glushka John; Orlando Ronald; Dean Jeffrey F. D.
Source:
Journal of economic entomology 2014 v.107 no.5 pp. 1931-1945
ISSN:
0022-0493
Subject:
Pinus; Sirex noctilio; antimicrobial peptides; conifers; explants; females; fungi; gene induction; genes; glycopeptides; glycosylation; heat stability; hosts; hydroxylation; liquid chromatography; oviposition; secretion; shoots; sugars; venoms; xylem
Abstract:
... During oviposition, female Sirex noctilio (F.) (Siricidae) woodwasps inject their conifer hosts with a venom gland secretion. The secretion induces a variety of host physiological changes that facilitate subsequent lethal infection by a symbiotic fungus. A heat-stable factor that can migrate from the site of oviposition in the trunk through the xylem to needles in the crown of attacked pines was p ...

38. Oxidation of Microcystin-LR by Ferrate(VI): Kinetics, Degradation Pathways, and Toxicity Assessments

Author:
Jiang Wenjun; Chen Long; Batchu Sudha Rani; Gardinali Piero R.; Jasa Libor; Marsalek Blahoslav; Zboril Radek; Dionysiou Dionysios D.; O’Shea Kevin E.; Sharma Virender K.
Source:
Environmental Science & Technology 2014 v.48 no.20 pp. 12164-12172
ISSN:
1520-5851
Subject:
alcohols; amino acids; aromatic compounds; byproducts; drinking water; fulvic acids; hydroxylation; ions; iron; lakes; liquid chromatography; mass spectrometry; microcystin-LR; models; oxidants; oxidation; pH; public health; risk; sorbic acid; toxicity; water treatment
Abstract:
... The presence of the potent cyanotoxin, microcystin-LR (MC-LR), in drinking water sources poses a serious risk to public health. The kinetics of the reactivity of ferrate(VI) (FeⱽᴵO₄²–, Fe(VI)) with MC-LR and model compounds (sorbic acid, sorbic alcohol, and glycine anhydride) are reported over a range of solution pH. The degradation of MC-LR followed second-order kinetics with the bimolecular rate ...
DOI:
10.1021/es5030355

39. Photocatalytic degradation of selected anticancer drugs and identification of their transformation products in water by liquid chromatography–high resolution mass spectrometry

Author:
P. Calza; C. Medana; M. Sarro; V. Rosato; R. Aigotti; C. Baiocchi; C. Minero
Source:
Journal of chromatography 2014 v.1362 pp. 135-144
ISSN:
0021-9673
Subject:
acute toxicity; aquatic environment; decarboxylation; doxorubicin; hydroxylation; ions; liquid chromatography; mass spectrometry; methotrexate; moieties; oxidation; photocatalysis; photolysis; sugars; titanium dioxide
Abstract:
... A study on the fate of two antineoplastic drugs, methotrexate and doxorubicin, in the aquatic environment is presented. The investigation involved a study of their decomposition under dark experiments, homogeneous photolysis and heterogeneous photocatalysis using titanium dioxide, the identification of intermediate compounds, as well as the assessment of acute toxicity over time. The analysis were ...
DOI:
10.1016/j.chroma.2014.08.035

40. Structural elucidation of the metabolites of lapachol in rats by liquid chromatography–tandem mass spectrometry

Author:
Lu Bai; Ying Han; Jinfeng Yao; Xiaorong Li; Yuhang Li; Pinxiang Xu; Ming Xue
Source:
Journal of Chromatography B 2014 v.944 pp. 128-135
ISSN:
1570-0232
Subject:
Tabebuia; bile; bioactive properties; biochemical pathways; chemical structure; drugs; hydrogenation; hydroxylation; ions; liquid chromatography; metabolism; metabolites; oxygen; rats; tandem mass spectrometry
Abstract:
... Lapachol is a natural naphthoquinone compound derived from Bignoniaceae (Tabebuia sp.) that possesses a range of significant biological activities. Nine phase I and four phase II metabolites of lapachol in rat bile were firstly elucidated and identified using a sensitive LC-ESI–MSn method. The molecular structures of the metabolites have been presented on the basis of the characteristics of their ...
DOI:
10.1016/j.jchromb.2013.11.024

41. Zero-valent iron mediated degradation of ciprofloxacin – Assessment of adsorption, operational parameters and degradation products

Author:
João Angelo de Lima Perini; Bianca Ferreira Silva; Raquel F. Pupo Nogueira
Source:
Chemosphere 2014 v.117 pp. 345-352
ISSN:
0045-6535
Subject:
acidification; adsorption; antibiotics; ciprofloxacin; dissolved organic carbon; fluorides; hydroxylation; iron; liquid chromatography; mass spectrometry; pH; piperazine; sulfuric acid
Abstract:
... The zero-valent iron (ZVI) mediated degradation of the antibiotic ciprofloxacin (CIP) was studied under oxic condition. Operational parameters such as ZVI concentration and initial pH value were evaluated. Increase of the ZVI concentration from 1 to 5gL−1 resulted in a sharp increase of the observed pseudo-first order rate constant of CIP degradation, reaching a plateau at around 10gL−1. The contr ...
DOI:
10.1016/j.chemosphere.2014.07.071

42. 4-Coumaroyl and Caffeoyl Shikimic Acids Inhibit 4-Coumaric Acid:Coenzyme A Ligases and Modulate Metabolic Flux for 3-Hydroxylation in Monolignol Biosynthesis of Populus trichocarpa

Author:
Chien-Yuan Lin; Jack P. Wang; Quanzi Li; Hsi-Chuan Chen; Jie Liu; Philip Loziuk; Jina Song; Cranos Williams; David C. Muddiman; Ronald R. Sederoff; Vincent L. Chiang
Source:
Molecular plant 2015 v.8 no.1 pp. 176-187
ISSN:
1674-2052
Subject:
Populus trichocarpa; biosynthesis; caffeic acid; coenzyme A; equations; gene expression regulation; genetically modified organisms; hydroxycinnamoyltransferase; hydroxylation; ligases; lignin; liquid chromatography; metabolites; shikimic acid; stemwood; tandem mass spectrometry; trans-cinnamate 4-monooxygenase
Abstract:
... Downregulation of 4-coumaric acid:coenzyme A ligase (4CL) can reduce lignin content in a number of plant species. In lignin precursor (monolignol) biosynthesis during stem wood formation in Populus trichocarpa, two enzymes, Ptr4CL3 and Ptr4CL5, catalyze the coenzyme A (CoA) ligation of 4-coumaric acid to 4-coumaroyl-CoA and caffeic acid to caffeoyl-CoA. CoA ligation of 4-coumaric acid is essential ...
DOI:
10.1016/j.molp.2014.12.003

43. Aerobic activated sludge transformation of methotrexate: Identification of biotransformation products

Author:
Tina Kosjek; Noelia Negreira; Miren López de Alda; Damià Barceló
Source:
Chemosphere 2015 v.119 pp. S42
ISSN:
0045-6535
Subject:
activated sludge; biotransformation; carbon; chemical bonding; chemical structure; hydroxylation; immunosuppression; ions; liquid chromatography; methotrexate
Abstract:
... This study describes the biotransformation of cytostatic and immunosuppressive pharmaceutical methotrexate. Its susceptibility to microbiological breakdown was studied in a batch biotransformation system, in presence or absence of carbon source and at two activated sludge concentrations. The primary focus of the present study are methotrexate biotransformation products, which were tentatively iden ...
DOI:
10.1016/j.chemosphere.2014.04.081

44. Candidate Reference Measurement Procedure for the Determination of (24R),25-Dihydroxyvitamin D3 in Human Serum Using Isotope-Dilution Liquid Chromatography–Tandem Mass Spectrometry

Author:
Tai Susan S.-C.; Nelson Michael A.
Source:
Analytical chemistry 2015 v.87 no.15 pp. 7964-7970
ISSN:
1520-6882
Subject:
atmospheric pressure; blood serum; cholecalciferol; ergocalciferol; humans; hydroxylation; ionization; isomers; kidney diseases; kidneys; liquid chromatography; liquid-liquid extraction; liver; metabolism; metabolites; monitoring; tandem mass spectrometry
Abstract:
... The two major forms of vitamin D, vitamin D3 and vitamin D2, are metabolized in the liver through hydroxylation to 25-hydroxyvitamin D species, and then further hydroxylated in the kidney to various dihydroxyvitamin D species. (24R),25-Dihydroxyvitamin D3 ((24R),25(OH)₂D3) is a major catabolite of 25-hydroxyvitamin D metabolism and is an important vitamin D metabolite used as a catabolism marker a ...
DOI:
10.1021/acs.analchem.5b01861

45. Carbon Stable Isotope Fractionation of Sulfamethoxazole during Biodegradation by Microbacterium sp. Strain BR1 and upon Direct Photolysis

Author:
Birkigt Jan; Gilevska Tetyana; Ricken Benjamin; Richnow Hans-Hermann; Vione Davide; Corvini Philippe F.-X.; Nijenhuis Ivonne; Cichocka Danuta
Source:
Environmental Science & Technology 2015 v.49 no.10 pp. 6029-6036
ISSN:
1520-5851
Subject:
Microbacterium; biodegradation; carbon; hydroxylation; isotope fractionation; liquid chromatography; mass spectrometry; metabolites; pH; photolysis; stable isotopes; sulfamethoxazole
Abstract:
... Carbon isotope fractionation of sulfamethoxazole (SMX) during biodegradation by Microbacterium sp. strain BR1 (ipso-hydroxylation) and upon direct photolysis was investigated. Carbon isotope signatures (δ¹³C) of SMX were measured by LC-IRMS (liquid chromatography coupled to isotope ratio mass spectrometry). A new LC-IRMS method for the SMX metabolite, 3-amino-5-methylisoxazole (3A5MI), was establi ...
DOI:
10.1021/acs.est.5b00367

46. Comparative metabolism of Lappaconitine in rat and human liver microsomes and in vivo of rat using ultra high-performance liquid chromatography–quadrupole/time-of-flight mass spectrometry

Author:
Shupeng Yang; Huiyan Zhang; Ross C. Beier; Feifei Sun; Xingyuan Cao; Jianzhong Shen; Zhanhui Wang; Suxia Zhang
Source:
Journal of Pharmaceutical and Biomedical Analysis 2015 v.110 pp. 1-11
ISSN:
0731-7085
Subject:
analgesics; biotransformation; humans; hydroxylation; ions; liquid chromatography; liver microsomes; mass spectrometry; metabolism; metabolites; neoplasms; oral administration; pain; rats
Abstract:
... Lappaconitine (LAP), a non-addictive potent analgesic drug, is broadly used to treat cancer and postoperative pain in many countries, and it also has antibiotic activity against Pseudomonas aeruginosa and Salmonella Typhi. Despite its widespread usage and potential for expanded use, its metabolism was poorly investigated. In this work, the metabolic fate of LAP in liver microsomes of the rat and h ...
Handle:
10113/5508066
DOI:
10.1016/j.jpba.2015.02.048

47. Comprehensive evaluation of the photo-transformation routes of trans-resveratrol

Author:
T. Rodríguez-Cabo; I. Rodríguez; M. Ramil; R. Cela
Source:
Journal of chromatography 2015 v.1410 pp. 129-139
ISSN:
0021-9673
Subject:
chemical bonding; cyclization reactions; hydroxylation; liquid chromatography; mass spectrometry; moieties; oxidation; phenanthrenes; phytoalexins; quartz; resveratrol; solar radiation
Abstract:
... Liquid chromatography (LC) combined with accurate mass spectrometry (MS), based on the use of a hybrid quadrupole time-of-flight (TOF) MS system, is employed to systematically investigate the photo-transformation routes of trans-resveratrol. Experiments were performed in quartz tubes, containing ethanolic solutions (12% v/v) of the precursor compound, exposed to different ultraviolet (UV) sources ...
DOI:
10.1016/j.chroma.2015.07.088

48. Construction of an Ultrahigh Pressure Liquid Chromatography-Tandem Mass Spectral Library of Plant Natural Products and Comparative Spectral Analyses

Author:
Lei Zhentian; Jing Li; Qiu Feng; Zhang Hua; Huhman David; Zhou Zhiqin; Sumner Lloyd W.
Source:
Analytical chemistry 2015 v.87 no.14 pp. 7373-7381
ISSN:
1520-6882
Subject:
electrochemistry; hydroxylation; isoflavonoids; liquid chromatography; neural networks; oxidation; phenylpropanoids; prediction; spectral analysis; spectrometers
Abstract:
... A plant natural product tandem mass spectral library has been constructed using authentic standards and purified compounds. Currently, the library contains 1734 tandem mass spectra for 289 compounds, with the majority (76%) of the compounds being plant phenolics such as flavonoids, isoflavonoids, and phenylpropanoids. Tandem mass spectra and chromatographic retention data were acquired on a triple ...
DOI:
10.1021/acs.analchem.5b01559

49. Determination of hydroxylated polychlorinated biphenyls by offline solid-phase extraction-liquid chromatography–tandem mass spectrometry using a molecularly imprinted polymer as a sorbent for sample preconcentration

Author:
Rongning Liang; Yan Zhao; Yang Su; Wei Qin
Source:
Talanta 2015 v.144 pp. 115-121
ISSN:
0039-9140
Subject:
hydroxylation; liquid chromatography; pH; polychlorinated biphenyls; polymers; solid phase extraction; solvents; sorbents; tandem mass spectrometry
Abstract:
... Hydroxylated polychlorinated biphenyls (OH-PCBs) can be detected by liquid chromatography–mass spectrometry coupled to solid-phase extraction (SPE) using a dummy molecularly imprinted polymer (DMIP) as a sorbent. The DMIP is prepared by using an analogue of OH-PCBs (i.e., 4, 4-dihydroxybiphenyl) as a dummy template, to avoid the leakage of the target molecules. The DMIP-SPE sorbent shows good reco ...
DOI:
10.1016/j.talanta.2015.05.064

50. Expression in yeast, new substrates, and construction of a first 3D model of human orphan cytochrome P450 2U1: Interpretation of substrate hydroxylation regioselectivity from docking studies

Author:
Lionel Ducassou; Gabriella Jonasson; Laura Dhers; Nicolas Pietrancosta; Booma Ramassamy; Yun Xu-Li; Marie-Anne Loriot; Philippe Beaune; Gildas Bertho; Murielle Lombard; Daniel Mansuy; François André; Jean-Luc Boucher
Source:
BBA - General Subjects 2015 v.1850 pp. 1426-1437
ISSN:
0304-4165
Subject:
Saccharomyces cerevisiae; active sites; arachidonic acid; brain; cytochrome P-450; drugs; genome; humans; hydroxylation; liquid chromatography; mass spectrometry; metabolism; metabolites; models; thymus gland; topology; yeasts
Abstract:
... Cytochrome P450 2U1 (CYP2U1) has been identified from the human genome and is highly conserved in the living kingdom. In humans, it has been found to be predominantly expressed in the thymus and in the brain. CYP2U1 is considered as an “orphan” enzyme as few data are available on its physiological function(s) and active site topology. Its only substrates reported so far were unsaturated fatty acid ...
DOI:
10.1016/j.bbagen.2015.03.014