Searched for: subject:"Biotransformation"
(1 - 20 of 59)

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Desprez, B. (author), Birk, B. (author), Blaauboer, B. (author), Boobis, A. (author), Carmichael, P. (author), Cronin, M.T.D. (author), Curie, R. (author), Daston, G. (author), Hubesch, B. (author), Jennings, P. (author), Klaric, M. (author), Kroese, D. (author), Mahony, C. (author), Ouédraogo, G. (author), Piersma, A. (author), Richarz, A.N. (author), Schwarz, M. (author), van Benthem, J. (author), van de Water, B. (author), Vinken, M. (author)
Repeated dose toxicity evaluation aims at assessing the occurrence of adverse effects following chronic or repeated exposure to chemicals. Non-animal approaches have gained importance in the last decades because of ethical considerations as well as due to scientific reasons calling for more human-based strategies. A critical aspect of this...
article 2019
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Reinen, J. (author), Nematollahi, L. (author), Fidder, A. (author), Vermeulen, N.P.E. (author), Noort, D. (author), Commandeur, J.N.M. (author)
Tri-ortho-cresyl phosphate (ToCP) is a multipurpose organophosphorus compound that is neurotoxic and suspected to be involved in aerotoxic syndrome in humans. It has been reported that not ToCP itself but a metabolite of ToCP, namely, 2-(ortho-cresyl)-4H-1,2,3-benzodioxaphosphoran-2-one (CBDP), may be responsible for this effect as it can...
article 2015
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Zune, Q. (author), Delepierre, A. (author), Gofflot, S. (author), Bauwens, J. (author), Twizere, J.C. (author), Punt, P.J. (author), Francis, F. (author), Toye, D. (author), Bawin, T. (author), Delvigne, F. (author)
Fungal biofilm is known to promote the excretion of secondary metabolites in accordance with solid-staterelated physiological mechanisms. This work is based on the comparative analysis of classical submerged fermentation with a fungal biofilmreactor for the production of a Gla::green fluorescent protein (GFP) fusion protein by Aspergillus oryzae...
article 2015
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Wijte, D. (author), van Baar, B.L.M. (author), Heck, A.J.R. (author), Altelaar, A.F.M. (author)
To enhance target production from biocatalysts, it is necessary to thoroughly understand the molecular mechanisms involved in production, degradation, and, importantly, adaptation to the required environment. One such bacterium with high potential for biocatalysis is the solvent-tolerant bacteria Pseudomonas putida S12, which, among others, is...
article 2011
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Kong, H. (author), Wang, M. (author), Venema, K. (author), Maathuis, A. (author), van der Heijden, R. (author), van der Greef, J. (author), Xu, G. (author), Hankemeier, T. (author), TNO Kwaliteit van Leven (author)
A high-performance liquid chromatography-high resolution Fourier transform ion cyclotron resonance mass spectrometry (HPLC-FTICR-MS) method was developed to investigate the metabolism of ginsenosides in in vitro models of the gastro-intestinal tract. The metabolites were identified by high-resolution tandem mass spectrometry. Degradation and...
article 2009
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de Jong, E. (author), Louisse, J. (author), Verwei, M. (author), Blaauboer, B.J. (author), van de Sandt, J.J.M. (author), Woutersen, R.A. (author), Rietjens, I.M.C.M. (author), Piersma, A.H. (author), TNO Kwaliteit van Leven (author)
The embryonic stem cell test (EST) has been proposed as an in vitro assay that might reduce animal experimentation in regulatory developmental toxicology. So far, evaluation of the EST was not performed using compounds within distinct chemical classes. Evaluation within a distinct class of chemically related compounds can define the usefulness...
article 2009
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Koopman, F.W. (author), de Winde, J.H. (author), Ruijssenaars, H.J. (author), TNO Kwaliteit van Leven (author)
The solvent-tolerant bacterium Pseudomonas putida S12 was engineered to efficiently utilize the C1 compounds methanol and formaldehyde as auxiliary substrate. The hps and phi genes of Bacillus brevis, encoding two key steps of the ribulose monophosphate (RuMP) pathway, were introduced to construct a pathway for the metabolism of the toxic...
article 2009
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Jeurissen, S.M.F. (author), Punt, A. (author), Delatour, T. (author), Rietjens, I.M.C.M. (author), TNO Kwaliteit van Leven (author)
The effects of a basil extract on the sulfation and concomitant DNA adduct formation of the proximate carcinogen 1′-hydroxyestragole were studied using rat and human liver S9 homogenates and the human hepatoma cell line HepG2. Basil was chosen since it contains the procarcinogen estragole that can be metabolized to 1′-hydroxyestragole by...
article 2008
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Smits, K.M. (author), Schouten, L.J. (author), van Dijk, B.A.C. (author), van Houwelingen, K. (author), van de Hulsbergen-Kaa, C.A. (author), Kiemeney, L.A.L.M. (author), van Houwelingen, K. (author), Goldbohm, R.A. (author), Oosterwijk, E. (author), van den Brandt, P.A. (author), TNO Kwaliteit van Leven (author)
Metabolic gene polymorphisms have previously been suggested as risk factors for renal cell carcinoma (RCC). These polymorphisms are involved in activation or detoxification of carcinogens in cigarette smoke which is another RCC risk factor. We evaluated gene-environment interactions between CYP1A1, GSTμ1 and smoking in a large population-based...
article 2008
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Jacobs, M.N. (author), Janssens, W. (author), Bernauer, U. (author), Brandon, E. (author), Coecke, S. (author), Combes, R. (author), Edwards, P. (author), Freidig, A. (author), Freyberger, A. (author), Kolanczyk, R. (author), Mc Ardie, C. (author), Mekenyan, O. (author), Schmieder, P. (author), Schrader, T. (author), Takeyoshi, M. (author), van der Burg, B. (author), TNO Kwaliteit van Leven (author)
Legislation and prospective legislative proposals in for instance the USA, Europe, and Japan require, or may require that chemicals are tested for their ability to disrupt the hormonal systems of mammals. Chemicals found to test positive are considered to be endocrine active substances (EAS) and may be putative endocrine disruptors (EDs). To...
article 2008
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Gibbs, S. (author), van de Sandt, J.J.M. (author), Merk, H.F. (author), Lockley, D.J. (author), Pendlington, R.U. (author), Pease, C.K. (author), TNO Kwaliteit van Leven (author)
In this review, we discuss and compare studies of xenobiotic metabolism in both human skin and 3D human skin reconstructs. In comparison to the liver, the skin is a less studied organ in terms of characterising metabolic capability. While the skin forms the major protective barrier to environmental chemical exposure, it is also a potential...
article 2007
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Ruijssenaars, H.J. (author), Sperling, E.M.G.M. (author), Wiegerinck, P.H.G. (author), Brands, F.T.L. (author), Wery, J. (author), de Bont, J.A.M. (author), TNO Kwaliteit van Leven (author)
A steroid 15β-hydroxylating whole-cell solvent tolerant biocatalyst was constructed by expressing the Bacillus megaterium steroid hydroxylase CYP106A2 in the solvent tolerant Pseudomonas putida S12. Testosterone hydroxylation was improved by a factor 16 by co-expressing Fer, a putative Fe-S protein from Bacillus subtilis. In addition, the...
article 2007
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Jeurissen, S.M.F. (author), Punt, A. (author), Boersma, M.G. (author), Bogaards, J.J.P. (author), Fiamegos, Y.C. (author), Schilter, B. (author), van Bladeren, P.J. (author), Cnubben, N.H.P. (author), Rietjens, I.M.C.M. (author), TNO Kwaliteit van Leven (author)
Human cytochrome P450 enzymes involved in the bioactivation of estragole to its proximate carcinogen 1′-hydroxyestragole were identified and compared to the enzymes of importance for 1′-hydroxylation of the related alkenylbenzenes methyleugenol and safrole. Incubations with Supersomes revealed that all enzymes tested, except P450 2C8, are...
article 2007
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Kienhuis, A.S. (author), Wortelboer, H.M. (author), Maas, W.J. (author), van Herwijnen, M. (author), Kleinjans, J.C.S. (author), van Delft, J.H.M. (author), Stierum, R.H. (author), TNO Kwaliteit van Leven (author)
A rapid decline of cytochrome P450 (CYP450) enzyme activities remains a drawback of rat hepatocyte-based in vitro cultures. Consequently, judgment of the toxic potential of compounds that need bioactivation by CYP450s may not be adequate using this model. In the present study, an improved hepatocyte-based in vitro system was developed with...
article 2007
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Jeurissen, S.M.F. (author), Bogaards, J.J.P. (author), Boersma, M.G. (author), ter Horst, J.P.F. (author), Awad, H.M. (author), Fiamegos, Y.C. (author), van Beek, T.A. (author), Alink, G.M. (author), Sudhölter, E.J.R. (author), Cnubben, N.H.P. (author), Rietjens, I.M.C.M. (author), TNO Kwaliteit van Leven (author)
In vitro studies were performed to elucidate the human cytochrome P450 enzymes involved in the bioactivation of methyleugenol to its proximate carcinogen 1′-hydroxymethyleugenol. Incubations with Supersomes, expressing individual P450 enzymes to a high level, revealed that P450 1A2, 2A6, 2C9, 2C19, and 2D6 are intrinsically able to 1′...
article 2006
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Heijne, W.H.M. (author), Jonker, D. (author), Stierum, R.H. (author), van Ommen, B. (author), Groten, J.P. (author), TNO Kwaliteit van Leven (author)
Benzene is an industrial chemical, component of automobile exhaust and cigarette smoke. After hepatic bioactivation benzene induces bone marrow, blood and hepatic toxicity. Using a toxicogenomics approach this study analysed the effects of benzene at three dose levels on gene expression in the liver after 28 daily doses. NMR based metabolomics...
article 2005
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Coecke, S. (author), Blaauboer, B.J. (author), Elaut, G. (author), Freeman, S. (author), Freidig, A. (author), Gensmantel, N. (author), Hoet, P. (author), Kapoulas, V.M. (author), Ladstetter, B. (author), Langley, G. (author), Leahy, D. (author), Mannens, G. (author), Meneguz, A. (author), Monshouwer, M. (author), Nemery, B. (author), Pelkonen, O. (author), Pfaller, W. (author), Prieto, P. (author), Proctor, N. (author), Rogiers, V. (author), Rostami-Hodjegan, A. (author), Sabbioni, E. (author), Steiling, W. (author), van de Sandt, J.J.M. (author), TNO Kwaliteit van Leven (author)
article 2005
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van der Woude, H. (author), Boersma, M.G. (author), Vervoort, J. (author), Rietjens, I.M.C.M. (author), TNO Voeding (author)
In this study, the HPLC, UV-vis, LC-MS, and 1H NMR characteristics of 14 different phase II mono- and mixed conjugates of quercetin were determined, providing a useful tool in the identification of quercetin phase II metabolite patterns in various biological systems. Using these data, the phase II metabolism of quercetin by different rat and...
article 2004
document
Michielse, C.B. (author), Ram, A.F.J. (author), Hooykaas, P.J.J. (author), van den Hondel, C.A.M.J.J. (author), TNO Voeding (author)
The Agrobacterium-mediated transformation of Aspergillus awamori was optimized using defined co-cultivation conditions, which resulted in a reproducible and efficient transformation system. Optimal co-cultivation conditions were used to study the role of Agrobacterium tumefaciens virulence proteins in T-DNA transfer. This study revealed that...
article 2004
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Jeurissen, S.M.F. (author), Bogaards, J.J.P. (author), Awad, H.M. (author), Boersma, M.G. (author), Brand, W. (author), Fiamegos, Y.C. (author), van Beek, T.A. (author), Alink, G.M. (author), Sudhölter, E.J.R. (author), Cnubben, N.H.P. (author), Rietjens, I.M.C.M. (author), TNO Voeding (author)
In the present study, the cytochrome P450 mediated bioactivation of safrole to its proximate carcinogenic metabolite, 1′-hydroxysafrole, has been investigated for the purpose of identifying the human P450 enzymes involved. The 1′-hydroxylation of safrole was characterized in a variety of in vitro test systems, including Supersomes, expressing...
article 2004
Searched for: subject:"Biotransformation"
(1 - 20 of 59)

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