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Biotransformation Of 4-Methoxyphenol In Rainbow Trout (Oncorhynchus Mykiss) Hepatic Microsomes, Steven P. Bradbury, R. Kolanczyk, P. Schmieder, T. Spizzo
Biotransformation Of 4-Methoxyphenol In Rainbow Trout (Oncorhynchus Mykiss) Hepatic Microsomes, Steven P. Bradbury, R. Kolanczyk, P. Schmieder, T. Spizzo
Steven P. Bradbury
Rainbow trout liver microsomes were used to study the O-demethylation and ring hydroxylation of 4-methoxyphenol (4-MP) (4-hydroxyanisole) at 11 and 25°C by directly measuring the production of the primary metabolite hydroquinone (HQ), 4-methoxycatechol (4-MCAT), and additional metabolites. An HPLC method with integrated ultraviolet (UV) and electrochemical detection (ECD) was developed for metabolite identification and quantification at low concentrations. Sample handling with appropriate buffers, solvents, low temperature and light prevented loss of extremely labile metabolites. Saturation kinetics for the production of HQ via O-demethylation of 4-MP (0.66–40 mM) was never achieved, with substrate solubility being the limiting factor. The linear rate …
Characterization Of Oxidation Products Of Tnt Metabolism In Aquatic Phytoremediation Systems Of Myriophyllum Aquaticum, R. Bhadra, R. J. Spanggord, D. G. Wayment, J. B. Hughes, Jacqueline V. Shanks
Characterization Of Oxidation Products Of Tnt Metabolism In Aquatic Phytoremediation Systems Of Myriophyllum Aquaticum, R. Bhadra, R. J. Spanggord, D. G. Wayment, J. B. Hughes, Jacqueline V. Shanks
Jacqueline V. Shanks
TNT transformation processes in sediment-free, “natural”, aquatic phytoremediation systems of Myriophyllum aquaticum were investigated with specific interest in oxidation products. Extraction procedures combining liquidliquid extractions and solid-phase extractions were developed for the isolation of the mostly acidic, oxidized TNT metabolites. Six compounds unique from the reduction products of TNT were isolated and characterized by UVvis, 1H, and 13C NMR spectroscopy, by mass spectroscopy, and by chemical synthesis where feasible. These compounds include 2-amino-4,6-dinitrobenzoic acid, 2,4-dinitro-6- hydroxy-benzyl alcohol, 2-N-acetoxyamino-4,6-dinitrobenzaldehyde, 2,4-dinitro-6-hydroxytoluene, and two binuclear metabolites unique from the customary azoxytetranitrotoluenes. The monoaryl compounds show clear evidence of oxidative transformations, methyl oxidation and/or …
Confirmation Of Conjugation Processes During Tnt Metabolism By Axenic Plant Roots, R. Bhadra, D. G. Wayment, J. B. Hughes, Jacqueline V. Shanks
Confirmation Of Conjugation Processes During Tnt Metabolism By Axenic Plant Roots, R. Bhadra, D. G. Wayment, J. B. Hughes, Jacqueline V. Shanks
Jacqueline V. Shanks
This paper examines processes in plants for the formation of fate products of TNT beyond its aminated reduction products, 2-amino-4,6-dinitrotoluene and 4-amino-2,6- dinitrotoluene. TNT metabolites were isolated and characterized in combination with temporal analyses of product profiles and 14C distribution, in microbe-free, axenic root cultures of Catharanthus roseus. Four unique TNTderived compounds were isolated. Using evidence from 1H NMR, mass spectroscopy, HPLC, acid hydrolysis, and enzymatic hydrolysis with â-glucuronidase and â-glucosidase, they were established as conjugates formed by reactions of the amine groups of 2-amino-4,6-dinitrotoluene and 4-amino-2,6-dinitrotoluene. From the mass spectral evidence, at least a six-carbon unit from the plant …