title: Effect of pepper lipoxygenase activity and its linked reactions on pigments of the pepper fruit.
abstract: The products formed during the enzymatic reaction catalyzed by the lipoxygenase of pepper (variety Agridulce) have in vitro a strong destructive action on the carotenoid pigments of the fruit. When conditions and proportions of enzyme and pigments are similar to those found in the fruit, and at a reaction temperature of 20 degrees C, almost 30% of the pigments are destroyed after 24 h of reaction. Of this amount, 2.5% is due to autoxidation of pigments, 4. 5% to oxidation induced by the presence of linoleic under saturating conditions, and the remaining 22% to the presence in the medium of reaction products of the lipoxygenase-catalyzed reaction. When the enzyme acts under substrate-saturating conditions, the rate of pigment destruction by lipoxygenase can be considered maximal at the experimental temperature. The fact that in vitro pepper lipoxygenase induces a heavy destruction of pigments and that, in vivo, its activity remains almost constant during over-ripening could explain why up to 40% of the pigment content in some varieties is lost during the postharvest period.
authors.affiliation: Departamento de Biotecnología de Alimentos, Instituto de la Grasa (CSIC), Avenida Padre García Tejero 4, Sevilla 41012, Spain. majaren@cica.es
authors.forename: M
authors.initials: M
authors.lastname: Jarén-Galán
authors.forename: M I
authors.initials: MI
authors.lastname: Mínguez-Mosquera
mesh_terms: D005638:Fruit / Q000201:enzymology*; D007700:Kinetics; D008084:Lipoxygenase / Q000378:metabolism*
chemical_list: D008084:Lipoxygenase