title: Assessment of polyphenolic content and in vitro antiradical characteristics of apple pomace.
abstract: Apple pomaces, a by-product in the apple juice processing, were subjected to evaluation as potential sources of antioxidant phytochemicals on the basis of their total content of phenolics (from 4.22 to 8.67mg/g), total flavonoids (from 0.45 to 1.19mg/g) and total flavan-3-ols (from 2.27 to 9.51mg/g), and in vitro antiradical activities. Some individual phenolic compounds including caffeic and chlorogenic acids, (+)-catechin and (-)-epicatechin, rutin, quercetin glycosides and phloridzin were identified and quantified by HPLC. The antiradical activity of apple pomaces was tested by measuring their ability to scavenge DPPH and hydroxyl radicals by ESR spectroscopy. The highest DPPH (EC50(DPPH)=6.33mg/ml) and hydroxyl (EC50(OH)=26.11mg/ml) radical scavenging activities were obtained in the case of Reinders pomace. The regression analysis produced moderate to high correlation coefficients between the antiradical activities (1/EC50(DPPH) and 1/EC50(OH)), and total phenolics, total flavonoids, total flavan-3-ols, and some individual phenolic compounds.
authors.affiliation: Faculty of Technology, University of Novi Sad, Bulevar Cara Lazara 1, 21000 Novi Sad, Serbia. Electronic address: cetkovic@tehnol.ns.ac.yu.
authors.forename: Gordana
authors.initials: G
authors.lastname: Ćetković
authors.affiliation: Faculty of Technology, University of Novi Sad, Bulevar Cara Lazara 1, 21000 Novi Sad, Serbia.
authors.forename: Jasna
authors.initials: J
authors.lastname: Čanadanović-Brunet
authors.affiliation: Faculty of Technology, University of Novi Sad, Bulevar Cara Lazara 1, 21000 Novi Sad, Serbia.
authors.forename: Sonja
authors.initials: S
authors.lastname: Djilas
authors.affiliation: Faculty of Technology, University of Novi Sad, Bulevar Cara Lazara 1, 21000 Novi Sad, Serbia.
authors.forename: Sladjana
authors.initials: S
authors.lastname: Savatović
authors.affiliation: Faculty of Technology, University of Novi Sad, Bulevar Cara Lazara 1, 21000 Novi Sad, Serbia.
authors.forename: Anamarija
authors.initials: A
authors.lastname: Mandić
authors.affiliation: Faculty of Technology, University of Novi Sad, Bulevar Cara Lazara 1, 21000 Novi Sad, Serbia.
authors.forename: Vesna
authors.initials: V
authors.lastname: Tumbas
keywords: Antiradical activity; Apple pomace; DPPH radical; ESR; HPLC; Hydroxyl radical; Phenolic compounds