Lupinus albus lipoxygenase has been shown to catalyse the formation of a trienoic fatty acid from arachidonic acid. In several ways, the conversion of arachidonic acid to conjugated aliphatic triene by Lupinus albus lipoxygenase bears resemblance with the reaction catalyzed by soybean lipoxygenase-1 in the double dioxygenation of arachidonic acid. Points of similarity include enzymatic removal of a hydrogen at carbon 10, double bond isomerization, and formation of a new carbon-to-oxygen bond. Based on the chromatographic and spectrometric analysis, the double dioxygenated product was identified as 8,15-dihydroperoxy-5,9,11,13-eicosatetraenoic acid.