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You searched for: Subject term hydroxylation Remove constraint Subject term: hydroxylation Subject term liquid chromatography Remove constraint Subject term: liquid chromatography
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1. 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

2. A comprehensive profiling of sulfatides in myelin from mouse brain using liquid chromatography coupled to high-resolution accurate tandem mass spectrometry

Author:
M. Pintado-Sierra; I. García-Álvarez; A. Bribián; E.M. Medina-Rodríguez; R. Lebrón-Aguilar; L. Garrido; F. de Castro; A. Fernández-Mayoralas; J.E. Quintanilla-López
Source:
Analytica chimica acta 2016 pp. -
ISSN:
0003-2670
Subject:
brain; central nervous system diseases; chemometrics; fatty acids; humans; hydroxylation; ionization; liquid chromatography; mice; myelin sheath; pathogenesis; tandem mass spectrometry
Abstract:
... Sulfatides are sulfoglycolipids found in the myelin sheath. The composition ratio of sulfatide molecular species changes with age, and it has also been associated with the pathogenesis of various human central nervous system diseases. However, profiling sulfatides in biological samples is difficult, due to the great variety of molecular species. In this work, a new, easy and reliable liquid chroma ...
DOI:
10.1016/j.aca.2016.11.054

3. 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

4. A tiered analytical approach for target, non-target and suspect screening analysis of polar transformation products of polycyclic aromatic compounds

Author:
Dieter Schemeth; Nikoline J. Nielsen; Jan T. Andersson; Jan H. Christensen
Source:
Chemosphere 2019 v.235 pp. 175-184
ISSN:
0045-6535
Subject:
anion exchange; aromatic compounds; basins; bioavailability; carboxylation; databases; dicarboxylic acids; environmental factors; fatty acids; gas chromatography-mass spectrometry; hydroxylation; liquid chromatography; photooxidation; polycyclic compounds; runoff; screening; solid phase extraction; toxicity; weathering; Arctic region
Abstract:
... Polycyclic aromatic compounds (PACs) possess toxicity towards humans, and their presence in the environment is unwanted. Polar transformation products (TPs) are more mobile, and can be considered emerging contaminants, as they represent a more bioavailable carrier of the same toxic properties. Acidic TPs has been proposed as an important class of polar TPs. This study presents a tiered analytical ...
DOI:
10.1016/j.chemosphere.2019.06.149

5. 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

6. Actinomycetes Rhodococcus ruber CGMCC 17550 degrades neonicotinoid insecticide nitenpyram via a novel hydroxylation pathway and remediates nitenpyram in surface water

Author:
Zhi-Ling Dai; Wen-Long Yang; Zhi-Xia Fan; Ling Guo; Zhong-Hua Liu; Yi-Jun Dai
Source:
Chemosphere 2021 v.270 pp. 128670
ISSN:
0045-6535
Subject:
Rhodococcus ruber; bacteria; biodegradation; biomass; bioremediation; cytochrome P-450; dissolved oxygen; ecosystems; fructose; glucose; hydroxylation; liquid chromatography; mass spectrometry; metabolism; metabolites; neurotoxins; nitenpyram; nuclear magnetic resonance spectroscopy; pollution; pyruvic acid; sewage treatment; surface water; xenobiotics
Abstract:
... Neonicotinoid insecticides are neurotoxicants that cause serious environmental pollution and ecosystem risks. In the present study, a nitenpyram-degrading bacterium, Rhodococcus ruber CGMCC 17550, was isolated from a nitenpyram production sewage treatment tank. Liquid chromatography-mass spectrometry analysis revealed R. ruber degraded nitenpyram via a novel hydroxylation pathway to form three dif ...
DOI:
10.1016/j.chemosphere.2020.128670

7. Activation of peroxymonosulfate by Fe doped g-C3N4 /graphene under visible light irradiation for Trimethoprim degradation

Author:
Ruobai Li; Jiashu Huang; Meixuan Cai; Jiaxing Huang; Zhijie Xie; Qianxin Zhang; Yang Liu; Haijin Liu; Wenying Lv; Guoguang Liu
Source:
Journal of hazardous materials 2020 v.384 pp. 121435
ISSN:
0304-3894
Subject:
acute toxicity; carbon nitride; catalysts; electron paramagnetic resonance spectroscopy; free radicals; graphene oxide; hydroxylation; iron; irradiation; liquid chromatography; oxidation; pH; polymers; remediation; superoxide anion; tandem mass spectrometry; toxic substances; trimethoprim
Abstract:
... Fe-doped g-C₃N₄ / graphene (rGO) composites were investigated as catalysts for the activation of peroxymonosulfate (PMS) to degrade Trimethoprim (TMP) under visible light irradiation. The rapid recombination of photogenerated electron-hole pairs in g-C₃N₄ may be suppressed by doping with Fe and incorporating rGO. The TMP degradation efficiency using 0.2% Fe-g-C₃N₄/2 wt% rGO/PMS was 3.8 times than ...
DOI:
10.1016/j.jhazmat.2019.121435

8. Advanced oxidation processes for the removal of [bmim][Sal] third generation ionic liquids: effect of water matrices and intermediates identification

Author:
Nemanja Banić; Biljana Abramović; Filip Šibul; Dejan Orčić; Malcolm Watson; Milan Vraneš; Slobodan Gadžurić
Source:
RSC advances 2016 v.6 no.58 pp. 52826-52837
ISSN:
2046-2069
Subject:
anions; aqueous solutions; cations; condensates; hydrogen peroxide; hydrolysis; hydroxylation; ionic liquids; lighting; liquid chromatography; organic matter; oxidation; pH; photolysis; pollutants; rain; rivers; tandem mass spectrometry; titanium dioxide; volatile organic compounds
Abstract:
... Unique properties of ionic liquids make them green alternatives for conventional volatile organic compounds. Due to increased production and the high stability of these substances, they could be classified as persistent pollutants and could break through classical treatment systems into natural waters. A preliminary ionic liquid hydrolysis study demonstrated a pH dependent degradation profile with ...
DOI:
10.1039/c6ra04416f

9. 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

10. Analysis of Metabolites of Anthraquinones by Human Fecal Bacteria Using UPLC-Q-TOF-HRMS/MS

Author:
Min Fan; Chongsheng Peng; Ying Peng; Min Zhang; Xiaobo Li
Source:
Chromatographia 2016 v.79 no.23-24 pp. 1593-1604
ISSN:
0009-5893
Subject:
bacteria; biochemical pathways; computer software; emodin; esterification; humans; hydroxylation; liquid chromatography; metabolism; metabolites; methylation; oxidation; tandem mass spectrometry
Abstract:
... This study aimed to investigate the metabolism of anthraquinones, including chrysophanol (1), rhein (2), aloe-emodin (3), emodin (4), sennoside A (5) and sennoside B (6), by mixed human fecal bacteria to clarify the relationship between their chemical structural characteristics and intestinal metabolism. Six parent compounds were incubated with mixed human fecal bacteria in vitro to study the meta ...
DOI:
10.1007/s10337-016-3183-0

11. Analysis of ibuprofen and its main metabolites in roots, shoots, and seeds of cowpea (Vigna unguiculata L. Walp) using liquid chromatography-quadrupole time-of-flight mass spectrometry: uptake, metabolism, and translocation

Author:
Yolanda Picó; Rodrigo Alvarez-Ruiz; Leonard Wijaya; Ahmed Alfarhan; Mohammed Alyemeni; Damià Barceló
Source:
Analytical and bioanalytical chemistry 2018 v.410 no.3 pp. 1163-1176
ISSN:
1618-2642
Subject:
Vigna unguiculata; amino acids; cowpeas; eggplants; hydroxylation; ibuprofen; ions; liquid chromatography; mass spectrometry; metabolism; metabolites; methanol; pH; quantitative analysis; roots; seeds; shoots; solid phase extraction; solvents
Abstract:
... A liquid chromatography quadruple time-of-flight mass spectrometry (LC–QqTOF-MS/MS) method was developed for simultaneous quantitative analysis of ibuprofen (IBU), 1- and 2-hydroxyibuprofen (1-OH IBU and 2-OH IBU), and carboxyibuprofen (CBX IBU) while preserving the ability of the instrument to get precursor and product ion mass spectra of non-target compounds. The trigger was the precursor ions r ...
DOI:
10.1007/s00216-017-0796-6

12. Analytical approaches for studying oxygenated lipids in the search of potential biomarkers by LC-MS

Author:
Alma Villaseñor; Joanna Godzien; Tomás Clive Barker-Tejeda; Carolina Gonzalez-Riano; Ángeles López-López; Danuta Dudzik; Ana Gradillas; Coral Barbas
Source:
Trends in analytical chemistry 2021 v.143 pp. 116367
ISSN:
0165-9936
Subject:
analytical chemistry; biomarkers; cardiolipins; cholesterol; derivatization; diabetes; glycerophospholipids; hydroxylation; lipid peroxidation; lipidomics; liquid chromatography; mass spectrometry; oxidation; sphingolipids
Abstract:
... Great advances in lipidomics during the last years have opened the door to a broader knowledge of oxygenated lipids. These substances are derived either from the inclusion of previously hydroxylated fatty acids in the lipid structure of sphingolipids and acyl-L-carnitines, or by enzymatic and non-enzymatic modifications (oxidized lipids) of glycerophospholipids (including cardiolipins), cholestery ...
DOI:
10.1016/j.trac.2021.116367

13. Application of liquid chromatography coupled to data-independent acquisition mass spectrometry for the metabolic profiling of N-ethyl heptedrone

Author:
Monica Mazzarino; Cristian Camuto; Fabio Comunità; Xavier de la Torre; Carlotta Stacchini; Francesco Botrè
Source:
Journal of chromatography 2021 v.1185 pp. 122989
ISSN:
1570-0232
Subject:
biotransformation; chemical species; cytochrome P-450; drugs; enzymatic hydrolysis; humans; hydroxylation; liquid chromatography; liquid-liquid extraction; liver microsomes; mass spectrometry; metabolism; metabolites; pH; uridine
Abstract:
... We have investigated the metabolic profile of N-ethyl heptedrone, a new designer synthetic stimulant drug, by using data independent acquisition mass spectrometry. Phase I and phase II metabolism was studied by in vitro models, followed by liquid-chromatography coupled to mass spectrometry, to characterize and pre-select the most diagnostic markers of intake. N-ethyl heptedrone was incubated in th ...
DOI:
10.1016/j.jchromb.2021.122989

14. Aqueous chlorination of acebutolol: kinetics, transformation by-products, and mechanism

Author:
Wan Nor Adira Wan Khalit; Kheng Soo Tay
Source:
Environmental science and pollution research international 2016 v.23 no.3 pp. 2521-2529
ISSN:
0944-1344
Subject:
aquatic environment; beta-adrenergic antagonists; byproducts; cardiovascular diseases; chlorination; chlorine; hydroxylation; liquid chromatography; mass spectrometry; oxidation; pH; propranolol; reaction kinetics
Abstract:
... This study investigated the reaction kinetics and the transformation by-products of acebutolol during aqueous chlorination. Acebutolol is one of the commonly used β-blockers for the treatment of cardiovascular diseases. It has been frequently detected in the aquatic environment. In the kinetics study, the second-order rate constant for the reaction between acebutolol and chlorine (k ₐₚₚ) was deter ...
DOI:
10.1007/s11356-015-5470-y

15. Aqueous chlorination of mefenamic acid: kinetics, transformation by-products and ecotoxicity assessment

Author:
Wan Nor Adira Wan Khalit; Kheng Soo Tay
Source:
Environmental science 2016 v.18 no.5 pp. 555-561
ISSN:
2050-7895
Subject:
byproducts; chlorination; chlorine; ecotoxicology; environmental science; hydroxylation; liquid chromatography; mass spectrometry; nonsteroidal anti-inflammatory agents; oxidation; pH; toxicity
Abstract:
... Mefenamic acid (Mfe) is one of the most frequently detected nonsteroidal anti-inflammatory drugs in the environment. This study investigated the kinetics and the transformation by-products of Mfe during aqueous chlorination. The potential ecotoxicity of the transformation by-products was also evaluated. In the kinetic study, the second-order rate constant (kₐₚₚ) for the reaction between Mfe and fr ...
DOI:
10.1039/c6em00017g

16. Assessing the bioremediation potential of indigenously isolated Klebsiella sp. WAH1 for diclofenac sodium: optimization, toxicity and metabolic pathway studies

Author:
Saloni Sharma; Hema Setia; Amrit Pal Toor
Source:
World journal of microbiology & biotechnology 2021 v.37 no.2 pp. 33
ISSN:
0959-3993
Subject:
Klebsiella pneumoniae; absorbance; activated sludge; anti-inflammatory agents; aquatic environment; biochemical pathways; bioremediation; biotechnology; carbon; chemical structure; decarboxylation; dechlorination; diclofenac; energy; hydroxylation; industrial wastewater; inoculum; liquid chromatography; pH; temperature; toxicity
Abstract:
... Among the various pharmaceutical pollutants, diclofenac sodium (DFS), a widely prescribed non-steroid anti-inflammatory drug is detected in the aquatic environment at concentrations which can be harmful to living organisms. Present study illustrates the isolation and characterization of strain Klebsiella pneumoniae WAH1 from activated sludge and its ability to degrade DFS as sole source of carbon ...
DOI:
10.1007/s11274-021-02998-4

17. Assessment of quinoxyfen phototransformation pathways by liquid chromatography coupled to accurate mass spectrometry

Author:
Priscila Ferri; María Ramil; Isaac Rodríguez; Rosângela Bergamasco; Angélica Marquetotti Salcedo Vieira; Rafael Cela
Source:
Analytical and bioanalytical chemistry 2017 v.409 no.11 pp. 2981-2991
ISSN:
1618-2642
Subject:
Daphnia magna; Pimephales promelas; chemical structure; computer software; ecotoxicology; half life; hydroxylation; irradiation; leaves; liquid chromatography; mass spectrometry; photolysis; quinoxyfen; river water; silicone; soil; solar radiation; wastewater; wavelengths
Abstract:
... Quinoxyfen has been recently identified as a priority hazardous substance in the field of the European water policy. In this work, its fate in aqueous samples and solid supports under UV and solar radiation is investigated. Diverse degradation experiments were carried out, at lab scale, using spiked aliquots of different aqueous matrices (ultrapure, treated wastewater and river water) irradiated a ...
DOI:
10.1007/s00216-017-0241-x

18. 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

19. Biodegradation Products of a Sulfonated Azo Dye in Aerobic Granular Sludge Sequencing Batch Reactors Treating Simulated Textile Wastewater

Author:
Rita D. G. Franca; M. Conceição Oliveira; Helena M. Pinheiro; Nídia D. Lourenço
Source:
ACS sustainable chemistry & engineering 2019 v.7 no.17 pp. 14697-14706
ISSN:
2168-0485
Subject:
aromatic amines; autoxidation; azo dyes; azorubine; batch systems; biodegradation; deamination; electrospray ionization mass spectrometry; hydrodynamics; hydroxylation; intermediate product; liquid chromatography; metabolites; nitrates; sludge; textile mill effluents
Abstract:
... This study focused on the biodegradation of an azo dye (Acid Red 14, AR14) in two anaerobic–aerobic sequencing batch reactors (SBRs) treating synthetic textile wastewater, operated with aerobic granular sludge under different hydrodynamic regimens. The aim was to investigate the fate of the anaerobic AR14 breakdown products (aromatic amines) during the SBRs’ aerobic reaction phase. Specifically, l ...
DOI:
10.1021/acssuschemeng.9b02635

20. Biodegradation and toxicity reduction of nonylphenol, 4-tert-octylphenol and 2,4-dichlorophenol by the ascomycetous fungus Thielavia sp HJ22: Identification of fungal metabolites and proposal of a putative pathway

Author:
Rim Mtibaà; Abdellah Ezzanad; Elisabet Aranda; Clementina Pozo; Bouthaina Ghariani; Javier Moraga; Moncef Nasri; Jesús Manuel Cantoral; Carlos Garrido; Tahar Mechichi
Source:
Science of the total environment 2020 v.708 pp. 135129
ISSN:
0048-9697
Subject:
2,4-dichlorophenol; Thielavia; Vibrio fischeri; biochemical pathways; biodegradation; biosorption; cytochrome P-450; enzyme inhibition; fungi; humans; hydroxylation; laccase; liquid chromatography; mass spectrometry; metabolites; nonylphenols; oxidation; pollutants; toxicity; xenobiotics
Abstract:
... Research on the biodegradation of emerging pollutants is gained great focus regarding their detrimental effects on the environment and humans. The objective of the present study was to evaluate the ability of the ascomycetes Thielavia sp HJ22 to remove the phenolic xenobiotics nonylphenol (NP), 4-tert-octylphenol (4-tert-OP) and 2,4-dichlorophenol (2,4-DCP). The strain showed efficient degradation ...
DOI:
10.1016/j.scitotenv.2019.135129