title: Liposome as a delivery system for carotenoids: comparative antioxidant activity of carotenoids as measured by ferric reducing antioxidant power, DPPH assay and lipid peroxidation.
abstract: This study was conducted to understand how carotenoids exerted antioxidant activity after encapsulation in a liposome delivery system, for food application. Three assays were selected to achieve a wide range of technical principles, including 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging, ferric reducing antioxidant powder (FRAP), and lipid peroxidation inhibition capacity (LPIC) during liposome preparation, auto-oxidation, or when induced by ferric iron/ascorbate. The antioxidant activity of carotenoids was measured either after they were mixed with preformed liposomes or after their incorporation into the liposomal system. Whatever the antioxidant model was, carotenoids displayed different antioxidant activities in suspension and in liposomes. The encapsulation could enhance the DPPH scavenging and FRAP activities of carotenoids. The strongest antioxidant activity was observed with lutein, followed by β-carotene, lycopene, and canthaxanthin. Furthermore, lipid peroxidation assay revealed a mutually protective relationship: the incorporation of either lutein or β-carotene not only exerts strong LPIC, but also protects them against pro-oxidation elements; however, the LPIC of lycopene and canthaxanthin on liposomes was weak or a pro-oxidation effect even appeared, concomitantly leading to the considerable depletion of these encapsulated carotenoids. The antioxidant activity of carotenoids after liposome encapsulation was not only related to their chemical reactivity, but also to their incorporation efficiencies into liposomal membrane and modulating effects on the membrane properties.
authors.affiliation: State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University , Lihu Road 1800, Wuxi, Jiangsu 214122, People's Republic of China.
authors.forename: Chen
authors.initials: C
authors.lastname: Tan
authors.forename: Jin
authors.initials: J
authors.lastname: Xue
authors.forename: Shabbar
authors.initials: S
authors.lastname: Abbas
authors.forename: Biao
authors.initials: B
authors.lastname: Feng
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Zhang
authors.forename: Shuqin
authors.initials: S
authors.lastname: Xia
mesh_terms: D000975:Antioxidants / Q000494:pharmacology*; D001713:Biphenyl Compounds / Q000737:chemistry; D002214:Capsules; D002338:Carotenoids / Q000008:administration & dosage* / Q000494:pharmacology*; D016503:Drug Delivery Systems; D005290:Ferric Compounds / Q000737:chemistry; D015227:Lipid Peroxidation / Q000187:drug effects; D008081:Liposomes; D014975:Lutein / Q000494:pharmacology; D000077276:Lycopene; D010084:Oxidation-Reduction; D010851:Picrates / Q000737:chemistry; D019207:beta Carotene / Q000494:pharmacology
chemical_list: D000975:Antioxidants; D001713:Biphenyl Compounds; D002214:Capsules; D005290:Ferric Compounds; D008081:Liposomes; D010851:Picrates; D019207:beta Carotene; D002338:Carotenoids; C004931:1,1-diphenyl-2-picrylhydrazyl; D000077276:Lycopene; D014975:Lutein