A soy extract catalyzes formation of 9-oxo-trans-12,13-epoxy-trans-10-octadecenoic acid from 13-hydroperoxy-cis-9,trans-11-octadecadienoic acid.

In the presence of oxygen, a crude soy extract converted 13-hydroperoxy-cis-9,trans-11-octadecadienoic acid into numerous products, from which 9-oxo-trans-12,13-epoxy-trans-10-octadecenoic acid was isolated. Additionally, the soy extract oxidized linoleic acid to the oxo-epoxyoctadecenoic acid, presumably via a sequential reaction involving lipoxygenase oxidation of linoleic acid followed by degradation of the resultant linoleic acid hydroperoxide. However, the linoleic acid substrate yielded two isomeric linoleic acid hydroperoxides and because of this, two isomeric oxoepoxyoctadecenoic acids.