Oxylipin formation in fungi: Biotransformation of arachidonic acid to 3-hydroxy-5,8-tetradecadienoic acid by Mucor genevensis

The soil fungus Mucor genevensis was shown to convert exogenous arachidonic acid to the oxylipin 3-hydroxy-5Z,8Z-tetradecadienoic acid (3-HTDE) as det ermined by gas chromatography/mass spectrometry, This metabolite was only f ound in the aqueous supernatant together with free linoleic acid, but not i n the final fungal biomass, In contrast, the corresponding primary arachido nic acid metabolite (3R)-hydroxy(5Z,8Z,11Z,14Z)-eicosatetraenoic acid (3-HE TE), which has been earlier shown to be produced by the yeast Dipodascopsis uninucleata, could not be detected. These observations may be plausibly ex plained by a retroconversion by M. genevensis of arachidonic acid to linole ic acid before the latter is metabolised to 3-HTDE. (C) 1998 Academic Press .