T. Beuerle et W. Schwab, Biosynthesis of R-(+)-octane-1,3-diol. Crucial role of beta-oxidation in the enantioselective generation of 1,3-diols in stored apples, LIPIDS, 34(6), 1999, pp. 617-625
The biosynthesis of R-octane-1,3-diol and R-5(Z)-octene-1,3-diol, two natur
al antimicrobial agents in apples and pears, was investigated in stored app
les after application of [9,10,12,13-H-3] linoleic acid, [9,10,12,13,15,16-
H-3]linolenic acid, [1-C-14]linoleic acid, [U-C-14]oleic acid, lipoxygenase
-derived metabolites of [9,10,12,13-H-3]linoleic acid, C-13(18)-labeled lin
oleic acid hydroperoxides, and H-2-labeled octanol derivatives. Analysis of
the products and quantification of incorporation and labeling pattern were
achieved by high-performance liquid chromatography-radiodetection, capilla
ry gas chromatography (GC)-isotope ratio mass spectrometry, and GC-mass spe
ctrometry analysis. Almost all the applied precursors were partly transform
ed into R-octane-1,3-diol. Linoleic acid derivatives, still containing the
12,13 cis double bond, and octanol derivatives oxy-functionalized at carbon
3 were the most efficient precursors of the 1,3-diol. The data imply that
R-octane-1,3-diol is generated in stored apples in the course of the beta-o
xidation from R-3-hydroxy-octanoyl-SCoA originating from 2-cis-octenoyl-SCo
A by enoyl-CoA hydratase; In an analogous fashion, R-5(Z)-octene-1,3-diol i
s formed from the unsaturated intermediate.