Analysis of oxylipins by high-performance liquid chromatography with evaporative light-scattering detection and particle beam-mass spectrometry

verfasst von
Bettina Rehbock, Dietmar Gansser, Ralf G. Berger
Abstract

The metabolism of 13S-hydroperoxy-9Z, 11E, 15Z-octadecatrienoic acid was investigated in a crude enzyme extract from mung bean seedlings (Phaseolus radiatus L.). Hydroperoxide-metabolizing activity was mainly due to a hydroperoxide lyase and, to a lesser extent, to an allene oxide synthase and a peroxygenase. Oxylipins originating from hydrolysis and cyclization of the allene oxide synthase product 12,13-epoxy-9Z, 11, 15Z-octadecatrienoic acid and from peroxygenase catalysis were identified by high-performance liquid chromatography (HPLC) particle beam-mass spectrometry (PB-MS) and quantified by normal-phase HPLC with an evaporative light-scattering detector (ELSD). An advantage of this methodology was the possibility to avoid extensive derivatization procedures commonly used for the gas chromatographic analysis of oxylipins. Owing to a comparable sample inlet system, the ELSD served an important analytical pilot function for the PB-MS: Qualitatively identical chromatographic patterns were obtained with both detection systems. The HPLC system enabled the separation of methyl 12-oxo-phytodienoate, methyl 11- hydroxy-12-oxo-9Z, 15Z-octadecadienoate, methyl 12-oxo-13-hydroxy-9Z, 15Z- octadecadienoate, methyl 9-hydroxy-12-oxo-10E, 15Z-octadecadienoate, methyl 13-hydroxy-9Z, 11E, 15Z-octadecatrienoate, methyl 15,16-epoxy-13-hydroxy-9Z, 11E-octadecadienoate, and methyl 13-hydroperoxy-9Z, 11E, 15Z- octadecatrienoate on a Lichrospher DIOL column within 33 rain. Compared with a diode array detector, the ELSD proved to be more sensitive in the case of methyl 12-oxo-13-hydroxy-9Z, 15Z-octadecadienoate by a factor of about 15. In addition volatile metabolites were analyzed by capillary gas chromatography. The yield of the hydroperoxide lyase product 2E-hexenal was 49%, whereas the sum of oxylipins reached about 15%.

Organisationseinheit(en)
Institut für Lebensmittelchemie
Typ
Artikel
Journal
LIPIDS
Band
32
Seiten
1003-1010
Anzahl der Seiten
8
ISSN
0024-4201
Publikationsdatum
01.09.1997
Publikationsstatus
Veröffentlicht
Peer-reviewed
Ja
ASJC Scopus Sachgebiete
Biochemie, Organische Chemie, Zellbiologie
Elektronische Version(en)
https://doi.org/10.1007/s11745-997-0130-0 (Zugang: Unbekannt)