Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7596015 | Food Chemistry | 2015 | 10 Pages |
Abstract
Little is known on structure-activity relationships of antioxidant anthocyanins. Raphanus sativus cv Sango sprouts are among the richest sources (270 mg/100 g fresh weight). We isolated from sprouts' juice 9 acylated anthocyanins, including 4 new compounds. All comprise a cyanidin core bearing 3-4 glucose units, multiply acylated with malonic and phenolic acids (ferulic and sinapic). All compounds were equally effective in inhibiting the autoxidation of linoleic acid in aqueous micelles, with rate constant for trapping peroxyl radicals kinh = (3.8 ± 0.7) Ã 104 M-1 s-1 at 37 °C. In acetonitrile solution kinh varied with acylation: (0.9-2.1) Ã 105 M-1 s-1 at 30 °C. Each molecule trapped a number n of peroxyl radicals ranging from 4 to 7. Anthocyanins bearing sinapic acid were more effective than those bearing the ferulic moiety. Under identical settings, deacylated cyanin, ferulic and sinapic acids had kinh of 0.4 Ã 105, 0.3 Ã 105 and 1.6 Ã 105 M-1 s-1 respectively, with n ranging 2-3. Results show the major role of acylation on antioxidant performance.
Related Topics
Physical Sciences and Engineering
Chemistry
Analytical Chemistry
Authors
Riccardo Matera, Simone Gabbanini, Serena Berretti, Riccardo Amorati, Gina Rosalinda De Nicola, Renato Iori, Luca Valgimigli,