Activation of lipoxygenase

Nunez-Delicado E, Sojo MM, Sanchez-Ferrer A and Garcia-Carmona F. 1999. Hydroperoxidase activity of lipoxygenase in the presence of cyclodextrins. Arch Biochem Biophys 367(2) 274-280. 

Melons stored at low temperatures showed different relative amounts of volatiles recovered by solvent extraction [34]. Some of the C9 unsaturated esters and alcohols presumably originated as a result of lipoxygenase activity. The previous results together with some investigations of the C9 unsaturated esters and alcohols suggested that the activity of lipoxygenase on melons seems to be dependent on cultivar, age, storage conditions, and sample location [65]. 

Figure 11.5 Effect of dietary curcumin on catalytic activity of lipoxygenase (LOX) in colon.

Oxidation products in form of reactive oxygen species are suspected to induce cell death [70,148]. Since generation of an oxidative burst requires the activation of kinases [83] and these in turn cause activation of membrane bound lipases we assume that the triggering event is the production of free PUFAs, followed by their peroxidation after activation of lipoxygenases as outlined above. 

Pinto MC, Garcia-Barrado JA, Macias P. Resveratrol is a potent inhibitor of the dioxygenase activity of lipoxygenase. J Agric Pood Chem 1999 47 4842-4846. 

Samson, E. and Stodolnik, L. 2001. Effect of freezing and salting on the activity of lipoxygenase of the muscle tissue and roe of Baltic herring, Acta Ichthyol. Piscat., 31(1), 97. 

In a mechanistic study using [10L- H,3- C]arachidonic acid as substrate for the platelet lipoxygenase, it was found that stereospecific removal of the L -hydrogen from C-10 of arachidonic acid is probably the initial step in conversion to 12-HPETE [190]. This study also describes the activation of lipoxygenase by endoperoxides, in... 

The oxidation of catecholamines by the hydroperoxidase activity of lipoxygenase (EC 1.13.11.12) is documented by Rosei et al. (1994) and NOnez-Delicado et al. (1996). o-Diphenols are easily studies spectrophotometrically since, when oxidised, they render coloured compounds, quinones, or their corresponding aminochromes. In the case of isoprenaline the maximum of the oxidation product was developed at 490 nm (NOnez-Delicado et al. 1999), which corresponds to that of the aminochrome product (Jim nez et al. 1985, NOnez-Delicado et al. 1996). 

In corneal tissue, ascorbic acid was able to inhibit the activity of lipoxygenase and reduce the production of 12-hydroxyeicosatetraeroic acid, the major lipoxygenase product produced by the cornea (Williams and Paterson, 1986). 

High performance liquid chromatographic methods (HPLC) were applied to analyse carotenoid [3], organic acid [4] and tocopherols [5]. The activity of lipoxygenase was spectrophotometrically determined by measuring A absorbance at 234 nm using linoleic acid as the substrate [6]. 

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