title: Carotenoids as protective response against oxidative damage in Dunaliella bardawil.
abstract: In the present work the relation between carotenoids production and cell response mechanisms to oxidative damage was studied. High light intensity and nitrogen starvation, both conditions, which may increase the oxidative damage in microalgae, significantly increased total carotenoids content in Dunaliella bardawil, the effect of N-starvation being more noticeable when acting synergetically with light on carotenoid production. S-starvation stimulated carotenoids production as much as N-starvation. The use of norflurazon, inhibitor of phytoene desaturase that blocks formation of epsilon-carotene from phytoene, caused a decrease of carotenoid content down to 5% that of the control cells incubated without the inhibitor. The decrease in the oxygen consumption rate of D. bardawil cells exposed to norflurazon suggests a connection between carotenoids desaturation and chloroplastic oxygen species dissipation processes reported in the literature for other algae. It is an indication of the carotenoids involvement in chloroplastic response mechanisms to oxidative damage.
authors.affiliation: Dpt. Química y CC.MM, Facultad de Ciencias Experimentales, Arca de Bioquimica, Campus de El Carmen, 21071 Huelva, Spain.
authors.forename: Alonso
authors.initials: A
authors.lastname: Salguero
authors.forename: Benito
authors.initials: B
authors.lastname: de la Morena
authors.forename: Javier
authors.initials: J
authors.lastname: Vigara
authors.forename: José M
authors.initials: JM
authors.lastname: Vega
authors.forename: Carlos
authors.initials: C
authors.lastname: Vilchez
authors.forename: Rosa
authors.initials: R
authors.lastname: León
mesh_terms: D002338:Carotenoids / Q000378:metabolism*; D002455:Cell Division / Q000187:drug effects / Q000528:radiation effects; D000460:Chlorophyta / Q000166:cytology / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects*; D004305:Dose-Response Relationship, Drug; D004307:Dose-Response Relationship, Radiation; D008027:Light; D009584:Nitrogen / Q000378:metabolism*; D018384:Oxidative Stress / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D010101:Oxygen Consumption / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D011724:Pyridazines / Q000494:pharmacology*; D011829:Radiation Dosage
chemical_list: D011724:Pyridazines; D002338:Carotenoids; C008677:norflurazone; D009584:Nitrogen