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Paulsen, Britt; Fredriksen, Kim Alex; Petersen, Dirk; Maes, Louis; Matheeussen, An & Naemi, Ali-Oddin
[Vis alle 11 forfattere av denne artikkelen]
(2019).
Synthesis directed towards bioactive ent-Ageloxime D and analogues.
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Paulsen, Britt; Fredriksen, Kim Alex; Petersen, Dirk; Maes, Louis; Matheeussen, An & Naemi, Ali-Oddin
[Vis alle 10 forfattere av denne artikkelen]
(2019).
Synthesis directed towards bioactive ent-Ageloxime D and analogues.
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Lerum, Hans Vigeland; Bouzga, Aud Mjærum; Jørgensen, Sissel; Petersen, Dirk; Eriksen, Dag Øistein & Hansen, Eddy Walther
[Vis alle 8 forfattere av denne artikkelen]
(2016).
Study of cadmium extraction from aqueous solutions with high chloride concentration using radiotracer and NMR
.
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Lerum, Hans Vigeland; Bouzga, Aud Mjærum; Jørgensen, Sissel; Petersen, Dirk; Eriksen, Dag Øistein & Hansen, Eddy Walther
[Vis alle 8 forfattere av denne artikkelen]
(2016).
LIQUID-LIQUID EXTRACTION OF CADMIUM CHLORIDE COMPLEXES STUDIED BY NMR.
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Wilson, Steven Ray Haakon; Petersen, Dirk; Rise, Frode & Krauss, Stefan
(2009).
Exporing the chemistry of the anti-cancer drug cycopamine with LC-MS and NMR.
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Wilson, Steven Ray Haakon; Strand, Martin Frank; Rise, Frode; Petersen, Dirk; Lundanes, Elsa & Krauss, Stefan
(2009).
NMR and LC-MS Analysis of Natural and Acid-Induced Isomers of Cyclopamine.
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Wilson, Steven Ray Haakon; Greibrokk, Tyge; Lundanes, Elsa; Malerød, Helle; Malterud, Karl Egil & Petersen, Dirk
[Vis alle 9 forfattere av denne artikkelen]
(2008).
Identification of the major metal compounds in blepharis aspera.
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Uhlig, Silvio; Ivanova, Lada; Petersen, Dirk & Kristensen, Ralf
(2008).
Indications of a novel class of naturally occurring enniatins containing N-methyl-threonine.
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Wilson, Steven Ray Haakon; Greibrokk, Tyge; Lundanes, Elsa; Malerød, Helle; Malterud, Karl Egil & Petersen, Dirk
[Vis alle 7 forfattere av denne artikkelen]
(2008).
Identification of the major metal compounds in blepharis aspera.
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Larsen, Kristofer; Petersen, Dirk; Wilkins, Alistair L.; Samdal, Ingunn; Sandvik, Morten & Rundberget, Thomas
[Vis alle 13 forfattere av denne artikkelen]
(2007).
Clarification of the C-35 Stereochemistries of Okadaic Acid, Dinophysistoxin-1, and Dinophysistoxin-2, and its consequences for binding to protein phosphatase.
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Malerød, Helle; Wilson, Steven Ray Haakon; Petersen, Dirk; Rise, Frode; Lundanes, Elsa & Greibrokk, Tyge
(2007).
Structure determination using on-line LC-MS/NMR.
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Larsen, Kristofer; Petersen, Dirk; Wilkins, Alistair L.; Goldstone, David; Arcus, Vickery & Rise, Frode
[Vis alle 7 forfattere av denne artikkelen]
(2007).
The C-35 Stereochemisties for Dinophysistoxin-1 and Dinophysistoxin-2 and its consequenses for biosynthesis and binding to protein phosphatases.
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Rise, Frode; Mmatli, Edward Eddie; Malerød, Helle; Wilson, Steven Ray Haakon; Lundanes, Elsa & Greibrokk, Tyge
[Vis alle 8 forfattere av denne artikkelen]
(2007).
Identification of Phenylethyl Glycosides from Blepharis Aspera by LC-UV-SPE-NMR/MS Hyphenation.
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Larsen, Kristofer; Wilkins, Alistair L.; Goldstone, David; Vickery, Arcus; Rise, Frode & Miles, Christopher O.
[Vis alle 7 forfattere av denne artikkelen]
(2007).
The C-35 Stereochemistries for Dinophysistoxin-1 and Dinophysistoxin-2 and its consequences for biosynthesis and binding to protein phosphatases.
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Rise, Frode; Malerød, Helle; Mmatli, Edward Eddie; Wilson, Steven Ray Haakon; Lundanes, Elsa & Greibrokk, Tyge
[Vis alle 8 forfattere av denne artikkelen]
(2007).
Identification of Phenylethyl Glycosides from Blepharis aspera by LC-UV-SPE-NMR/MS Hyphenation.
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Larsen, Kristofer; Petersen, Dirk; Wilkins, A.L.; Samdal, Ingunn; Sandvik, Morten & Rundberget, Thomas
[Vis alle 13 forfattere av denne artikkelen]
(2006).
The C-35 Stereochemistries for dinophysistoxin - 1 and dinophysistoxin - 2 and its consequences for binding to proteinphosphatases.
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Rise, Frode; Mmatli, Edward Eddie; Malerød, Helle; Wilson, Steven Ray Haakon; Lundanes, Elsa & Greibrokk, Tyge
[Vis alle 8 forfattere av denne artikkelen]
(2006).
Identification of Phenylethyl Glycosides from Blepharis aspera by LC-UV-SPE-NMR/MS Hyphenation.
Vis sammendrag
Conclusions
Verbascoside and isoverbascoside were isolated and purified from Blepharis
aspera. An in lab designed LC-UV-SPE-NMR/MS system was successfully used to separate the two compounds and to obtain their 1H NMR data online using a 30 micro liter LC-NMR probe.
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Berg, Tom Christian; Bakken, Vebjørn; Gundersen, Lise-Lotte & Petersen, Dirk
(2006).
Cyclisation and Rearrangement Products from Coupling Reactions between terminal o-Alkynylphenols or o-ethynyl(hydroxymethyl)benzene and 6-Halopurines.
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Uhlig, Silvio; Petersen, Dirk; Wilkins, Alistair Lawrence & Flåøyen, Arne
(2006).
2-amino-14,16-dimethyl-octadecan-3-ol - A Noval Fusarium Metabolite with Biological Activity.
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Larsen, Kristofer; Rise, Frode; Petersen, Dirk; Miles, Christopher O. & Wilkins, Alistair L.
(2006).
Clarification of the C-35 Stereochemistry of DTX-1.
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Larsen, Kristofer; Rise, Frode; Petersen, Dirk; Miles, Christopher O. & Wilkins, Alistair L.
(2006).
Clarification of the C-35 Stereochemistry of DTX-1.
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Rise, Frode; Petersen, Dirk; Nebojsa, Simic; Wilson, Steven Ray & Malerød, Helle
(2005).
LC-NMR.
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Berg, Tom Christian; Gundersen, Lise-Lotte & Petersen, Dirk
(2005).
Cyclization Reactions on 6-(Hydroxyalk-1-ynyl)purines.
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Miles, Christopher; Wilkins, A.L.; Samdal, Ingunn; Sandvik, Morten; Rundberget, Thomas & Petersen, Dirk
[Vis alle 14 forfattere av denne artikkelen]
(2004).
PTX-12, a New Pectenotoxin Present in Scandinavian Shellfish and Dinophysis.
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Rise, Frode; Petersen, Dirk; Nebojsa, Simic & Wilson, Steven Ray
(2004).
LC-NMR.
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Uhlig, Silvio; Petersen, Dirk; Wilkins, Alistair Lawrence & Flåøyen, Arne
(2004).
A Novel Fusarium Metabolite with Biological Activity.
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Aarnes, Halvor; Eriksen, Aud Else Berglen; Petersen, Dirk & Rise, Frode
(2004).
In Vivo 14N-NMR and 31P-NMR: intracellular pH in Norway spruce (Picea abies) seedlings grown on ammonium or nitrate.
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Briggs, L.R.; Fitzgerald, Joan; Garthwaite, I.; Miles, Christopher; Ross, Karen & Towers, N.R.
[Vis alle 11 forfattere av denne artikkelen]
(2002).
Immunoassays for analysis of yessotoxins.
Vis sammendrag
Polyclonal antibodies that bind to yessotoxin (YTX) and its analogues have been produced. The antibodies were used to develop ELISAs as part of a research programme carried out at AgResearch to develop rapid screening methods for algal toxins in shellfish. Direct and indirect formats for the assays have been optimised and yessotoxins have been quantified in water samples, shellfish (both whole flesh and hepatopancreas) and algal extracts. The most sensitive format has a limit of quantitation of 20 pg/mL. Dilution of shellfish extracts 300-fold eliminates matrix effects. Although dilution raises the limit of quantitation, assay sensitivity is still well below the EU recommended maximum levels of 1 mg/kg of shellfish flesh.
Cross-reactivity studies have demonstrated that the anti-YTX antibodies also bind YTXs modified at the C-40 end of the molecule, as well as homoYTX (although cross-reactivities are lower for analogues where functional groups on C-1 are modified). The assay is therefore able to detect all the YTX analogues that the EU currently requires shellfish to be tested for. In addition, because of the immunogen chemistry, it is expected that the antibodies will also recognise the toxic analogues adriatoxin and carboxyessotoxin¿although confirmation of this has not been possible due to a lack of standards for these toxins. Because the antibodies can bind to a wide range of YTX analogues, the ELISA response for algal and shellfish samples is often greater than with other analytical methods (e.g. HPLC) that do not measure all YTX analogues. Nevertheless, results from ELISA and LC-MS analyses of shellfish extracts showed a good linear correlation.
Studies are under way to determine the nature of the YTX analogues responsible for the increased response of the ELISA. Chromatography of extracts from Protoceratium reticulatum followed by ELISA analysis has provided ELISA-reactive fractions. Preliminary analysis of these fractions by NMR and LC-MS has confirmed the presence of a complex mixture of yessotoxin analogues. Similar studies on contaminated shellfish are also planned.
Commercialisation of a yessotoxin ELISA is now in progress.
Keyword1: yessotoxin
Keyword2: immunoassay
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Briggs, L.R.; Miles, C. O.; Garthaite, I.; Ross, Karen; Towers, N.R. & Samdal, Ingunn
[Vis alle 10 forfattere av denne artikkelen]
(2002).
Immunoassays for the analysis of yessotoxins.
Vis sammendrag
Polyclonal antibodies that bind to yessotoxin (YTX) and its analogues have been produced. The antibodies were used to develop ELISAs as part of a research programme carried out at AgResearch to develop rapid screening methods for algal toxins in shellfish. Direct and indirect formats for the assays have been optimised and yessotoxins have been quantified in water samples, shellfish (both whole flesh and hepatopancreas) and algal extracts. The most sensitive format has a limit of quantitation of 20 pg/mL. Dilution of shellfish extracts 300-fold eliminates matrix effects. Although dilution raises the limit of quantitation, assay sensitivity is still well below the EU recommended maximum levels of 1 mg/kg of shellfish flesh.
Cross-reactivity studies have demonstrated that the anti-YTX antibodies also bind YTXs modified at the C-40 end of the molecule, as well as homoYTX (although cross-reactivities are lower for analogues where functional groups on C-1 are modified). The assay is therefore able to detect all the YTX analogues that the EU currently requires shellfish to be tested for. In addition, because of the immunogen chemistry, it is expected that the antibodies will also recognise the toxic analogues adriatoxin and carboxyessotoxin¿although confirmation of this has not been possible due to a lack of standards for these toxins. Because the antibodies can bind to a wide range of YTX analogues, the ELISA response for algal and shellfish samples is often greater than with other analytical methods (e.g. HPLC) that do not measure all YTX analogues. Nevertheless, results from ELISA and LC-MS analyses of shellfish extracts showed a good linear correlation.
Studies are under way to determine the nature of the YTX analogues responsible for the increased response of the ELISA. Chromatography of extracts from Protoceratium reticulatum followed by ELISA analysis has provided ELISA-reactive fractions. Preliminary analysis of these fractions by NMR and LC-MS has confirmed the presence of a complex mixture of yessotoxin analogues. Similar studies on contaminated shellfish are also planned.
Commercialisation of a yessotoxin ELISA is now in progress.
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Spilsberg, Bjørn; Rise, Frode; Petersen, Dirk & Nissen-Meyer, Jon
(2000).
SECRETION OF THYMIDINE BY HYBRIDOMA CELLS.
Vis sammendrag
Myeloma and hybridoma cells have been reported to secrete a low molecular weight growth inhibitory factor (Rønning et al., 1991, Cytotechnology 7, 15-24; Røe, Ø. et al., 1999, Biochem. Biophys. Res. Commun. 254, 138-142). The factor was identified as thymidine by NMR spectroscopy after isolation to homogeneity from hybridoma cell cultures by ultrafiltration, dialysis concentration and reverse phase chromatography under acidic and neutral conditions. Taken together, the results suggest that hybridoma cells and possibly myeloma cells secrete thymidine.
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Spilsberg, Bjørn; Rise, Frode; Petersen, Dirk; Rønning, Øystein W. & Nissen-Meyer, Jon
(2000).
The low-molecular-weight "growth inhibitory factor" produced by hybridoma cell cultures identified as thymidine by NMR-spectroscopy.
Vis sammendrag
Myeloma and hybridoma cells have been reported to secrete a low-molecular-weight growth inhibitory factor (1, 2). This factor was isolated to homogeneity from the media (4.0 liters) of hybridoma cell cultures by ultrafiltration, ¿dialysis concentration¿ and reverse phase chromatography under acidic and neutral conditions. The inhibitory factor was identified as thymidine by NMR spectroscopy.
(1) Rønning, Ø.W., Schartum, M., Winsnes, A. and Lindberg, G. (1991) Growth limitation in hybridoma cell cultures: The role of inhibitory or toxic metabolites. Cytotechnology 7, 15-24.
(2) Røe, Ø., Brondz, I., Rønning, Ø. and Nissen-Meyer, J. (1999) Isolation of a low-molecular-weight growth inhibitory factor from hybridoma cell cultures. Biochem. Biophys. Res. Commun. 254, 138-142.
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Spilsberg, Bjørn; Rise, Frode; Petersen, Dirk; Rønning, Øystein W. & Nissen-Meyer, Jon
(2000).
The low-molecular-weight "growth inhibitory factor" produced by hybridoma cell culture identifed as thymidine by NMR-spectroscopy.
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