title: Flavonoids in Microheterogeneous Media, Relationship between Their Relative Location and Their Reactivity towards Singlet Oxygen.
abstract: In this work, the relationship between the molecular structure of three flavonoids (kaempferol, quercetin and morin), their relative location in microheterogeneous media (liposomes and erythrocyte membranes) and their reactivity against singlet oxygen was studied. The changes observed in membrane fluidity induced by the presence of these flavonoids and the influence of their lipophilicity/hydrophilicity on the antioxidant activity in lipid membranes were evaluated by means of fluorescent probes such as Laurdan and diphenylhexatriene (DPH). The small differences observed for the value of generalized polarization of Laurdan (GP) curves in function of the concentration of flavonoids, indicate that these three compounds promote similar alterations in liposomes and erythrocyte membranes. In addition, these compounds do not produce changes in fluorescence anisotropy of DPH, discarding their location in deeper regions of the lipid bilayer. The determined chemical reactivity sequence is similar in all the studied media (kaempferol < quercetin < morin). Morin is approximately 10 times more reactive than quercetin and 20 to 30 times greater than kaempferol, depending on the medium.
authors.affiliation: Departamento de Química Orgánica y Fisicoquímica, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile.
authors.forename: Germán
authors.initials: G
authors.lastname: Günther
authors.affiliation: Departamento de Química Orgánica y Fisicoquímica, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Berríos
authors.affiliation: Departamento de Ciencias Químicas, Facultad de Ciencias Exactas, Universidad Andrés Bello, Santiago, Chile.
authors.forename: Nancy
authors.initials: N
authors.lastname: Pizarro
authors.affiliation: Departamento de Ciencias y Tecnología Farmacéuticas, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile.
authors.forename: Karina
authors.initials: K
authors.lastname: Valdés
authors.affiliation: Departamento de Ciencias y Tecnología Farmacéuticas, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile.
authors.forename: Guillermo
authors.initials: G
authors.lastname: Montero
authors.affiliation: Departamento de Ciencias y Tecnología Farmacéuticas, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile.
authors.forename: Francisco
authors.initials: F
authors.lastname: Arriagada
authors.affiliation: Departamento de Ciencias y Tecnología Farmacéuticas, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile.
authors.forename: Javier
authors.initials: J
authors.lastname: Morales
mesh_terms: D005419:Flavonoids / Q000737:chemistry* / Q000494:pharmacology; D016166:Free Radical Scavengers / Q000737:chemistry* / Q000494:pharmacology; D008081:Liposomes / Q000737:chemistry; D026082:Singlet Oxygen / Q000737:chemistry*
chemical_list: D005419:Flavonoids; D016166:Free Radical Scavengers; D008081:Liposomes; D026082:Singlet Oxygen