Steric analysis of 8-hydroxy- and 10-hydroxyoctadecadienoic acids and dihydroxyoctadecadienoic acids formed from 8R-hydroperoxyoctadecadienoic acid by hydroperoxide isomerases
2007 (English)In: Analytical Biochemistry, ISSN 0003-2697, E-ISSN 1096-0309, Vol. 367, no 2, 238-246 p.Article in journal (Refereed) Published
8-Hydroxyoctadeca-9Z,12Z-dienoic acid (8-HODE) and 10-hydroxyoctadeca-8E,12Z-octadecadienoic acid (10-HODE) are produced by fungi, e.g., 8R-HODE by Gaeumannomyces graminis (take-all of wheat) and Aspergillus nidulans, 10S-HODE by Lentinula edodes, and 10R-HODE by Epichloe typhina. Racemic [8-2H]8-HODE and [10-2H]10-HODE were prepared by oxidation of 8- and 10-HODE to keto fatty acids by Dess–Martin periodinane followed by reduction to hydroxy fatty acids with NaB2H4. The hydroxy fatty acids were analyzed by chiral phase high-performance liquid chromatography–tandem mass spectrometry (HPLC–MS/MS) with 8R-HODE and 10S-HODE as standards. 8R-HODE eluted after 8S-HODE on silica with cellulose tribenzoate (Chiralcel OB-H), and 10S-HODE eluted before 10R-HODE on silica with an aromatic chiral selector (Reprosil Chiral-NR). 5S,8R-Dihydroxyoctadeca-9Z,12Z-dienoic acid (5S,8R-DiHODE) is formed from 18:2n-6 by A. nidulans and 8R,11S-dihydroxyoctadeca-9Z,12Z-dienoic acid (8R,11S-DiHODE) by Agaricus bisporus. 8R-Hydroperoxylinoleic acid (8R-HPODE) can be transformed to 5S,8R-DiHODE and 8R,11-DiHODE by Aspergillus spp., and 8R,13-dihydroxy-9Z,11E-dienoic acid (8R,13-DiHODE) can also be detected. We prepared racemic [5,8-2H2]5,8- and [8,11-2H2]8,11-DiHODE by oxidation and reduction as above and 8R,13S- and 8R,13R-DiHODE by oxidation of 8R-HODE by S and R lipoxygenases. The diastereoisomers were separated and identified by normal phase HPLC–MS/MS analysis. We used the methods for steric analysis of fungal oxylipins. Aspergillus spp. produced 8R-HODE (>95% R), 10R-HODE (>70% R), and 5S,8R- and 8R,11S-DiHODE with high stereoselectivity (>95%), whereas 8R,13-DiHODE was likely formed by nonenzymatic hydrolysis of 8R,11S-DiHODE.
Place, publisher, year, edition, pages
2007. Vol. 367, no 2, 238-246 p.
Aspergillus, Chiralcel OB, 5, 8-DiHODE, 8, 11-DiHODE, Normal phase HPLC, Reprosil chiral NR, Ion trap mass spectrometry
IdentifiersURN: urn:nbn:se:uu:diva-15041DOI: 10.1016/j.ab.2007.04.045ISI: 000248198500012PubMedID: 17553451OAI: oai:DiVA.org:uu-15041DiVA: diva2:42812