10-Hydroxy-8(Z)-octadecenoic acid, an intermediate in the bioconversion of oleic acid to 7,10-dihydroxy-8(E)-octadecenoic acid

Previously, we reported the discovery of a new compound, 7,10-dihydroxy-8(E)-octadecenoic acid (DOD) which was produced from oleic acid by a new bacterial isolate PR3 [6,7]. The reaction is unique in that it involves a hydroxylation at two positions and a rearrangement of the double bond of the substrate molecule. Now, we have isolated another compound from the reaction mixture determined by GC/MS to be 10-hydroxy-8-octadecenoic acid (HOD). NMR and IR data indicate that the unsaturation is probably cis. The optimum pH and temperature for the production of HOD by strain PR3 were 6.5 and 30 degrees C, about the same as those for DOD. However, the amount of HOD detected remained small throughout an 48-h reaction period during which the amount of DOD increased sharply. At 48 h of reaction, the ratio between HOD:DOD was 1:10. HOD maybe an intermediate in the biosynthesis of DOD from oleic acid.