title: Isolation and structure elucidation of antioxidant polyphenols from quince (Cydonia vulgaris) peels.
abstract: Thirteen new compounds, as well as 16 already known, have been isolated from organic extracts of peels of Cydonia vulgaris, a fruit of a shrub belonging to the same tribe as the apple. All of the structures were elucidated by EI- or ESI-MS and (1)H and (13)C NMR after purification of individual compounds by HPLC. Thirteen fatty acid esters of cinnamyl alcohols, three fatty acid esters of hydroxybenzoic acid, three fatty acid esters of hydroxybenzaldehyde, three glucosides of aromatic acids, four chlorogenic acids, two flavonols, and a benzylamine have been identified. The fatty acid moieties have been identified by GC-MS analysis of the methanolysis products. All of the compounds were tested for their radical scavenging and antioxidant activities by measuring their capacity to scavenge the 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical and anion superoxide radical and to induce the reduction of Mo(VI) to Mo(V). The chlorogenic acids and the flavonols exhibited more antioxidant and radical scavenger capacity than the positive standards alpha-tocopherol and ascorbic acid. The results of the tests were analyzed by cluster analysis that grouped all of the compounds on the basis of the substituents on the aromatic ring.
authors.affiliation: artimento di Scienze della Vita, Laboratory of Phytochemistry, Seconda Università degli Studi di Napoli, Via Vivaldi 43, 81100 Caserta, Italy. antonio.fiorentino@unina2.it
authors.forename: Antonio
authors.initials: A
authors.lastname: Fiorentino
authors.forename: Brigida
authors.initials: B
authors.lastname: D'Abrosca
authors.forename: Severina
authors.initials: S
authors.lastname: Pacifico
authors.forename: Claudio
authors.initials: C
authors.lastname: Mastellone
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Piscopo
authors.forename: Romualdo
authors.initials: R
authors.lastname: Caputo
authors.forename: Pietro
authors.initials: P
authors.lastname: Monaco
mesh_terms: D000975:Antioxidants / Q000737:chemistry* / Q000302:isolation & purification*; D002851:Chromatography, High Pressure Liquid; D005419:Flavonoids / Q000737:chemistry* / Q000302:isolation & purification*; D016166:Free Radical Scavengers; D005638:Fruit / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D010636:Phenols / Q000737:chemistry* / Q000302:isolation & purification*; D059808:Polyphenols; D027824:Rosaceae / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization; D013329:Structure-Activity Relationship
chemical_list: D000975:Antioxidants; D005419:Flavonoids; D016166:Free Radical Scavengers; D010636:Phenols; D059808:Polyphenols