Conversion of linoleic acid into novel oxylipins by the mushroom Agaricus bisporus.
Lipids
; 40(11): 1163-70, 2005 Nov.
Article
em En
| MEDLINE
| ID: mdl-16459929
ABSTRACT
Oxylipins are associated with important processes of the fungal life cycle, such as spore formation. Here, we report the formation of FA metabolites in Agaricus bisporus. Incubation of a crude extract of lamellae with linoleic acid (182) led to the extensive formation of two oxylipins. They were identified as 8(R)-hydroxy-9Z,12Z-octadecadienoic acid (8-HOD) and 8(R),11 (S)-dihydroxy-9Z,12Z-octadecadienoic acid (8,11-diHOD) by using RP-HPLC, GC-MS, IR, GC-MS analysis of diastereomeric derivatives, and 1H NMR and 13C NMR spectroscopy. Neither compound has been reported before in A. bisporus. Oleic (181), alpha-linolenic (183n-3), and gamma-linolenic (183n-6) acids were converted into their 8-hydroxy derivatives as well, and 183n-3 was further metabolized to its 8,11-diol derivative. Reactions with [U-13C]182 demonstrated that the compounds 8-HOD and 8,11-diHOD were formed from exogenously supplied 182. When [U-13C]8-HOD was supplied, it was not converted into 8,11-diHOD, indicating that it was not an intermediate in the formation of 8,11-diHOD. When a crude extract of A. bisporus was incubated under an atmosphere of 16O2/18O2, the two hydroxyl groups of 8,11-diHOD contained either two 180 atoms or two 60 atoms. Species that contained one of each isotope could not be detected. We propose that the formation of the 8,11-dihydroxy compounds occurs through either an 8,11-endoperoxy, an 8-peroxo free radical, or an 8-hydroperoxy intermediate. In the latter case, the reaction should be catalyzed by dioxygenase with novel specificity.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Agaricus
/
Ácido Linoleico
/
Ácidos Graxos Insaturados
Idioma:
En
Revista:
Lipids
Ano de publicação:
2005
Tipo de documento:
Article
País de afiliação:
Holanda