Antioxidative Compounds from the Outer Scales of Onion
- 16 September 2005
- journal article
- Published by American Chemical Society (ACS) in Journal of Agricultural and Food Chemistry
- Vol. 53 (21), 8183-8189
- https://doi.org/10.1021/jf051264d
Abstract
Antioxidative compounds were isolated from the methanol extract of dry outer scales of onion (Allium cepa L.). Nine phenolic compounds (1 − 9) were finally obtained by reversed-phase high-performance liquid chromatography, and their structures were elucidated by NMR and mass spectrometry analyses. They were the six known compounds, protocatechuic acid (1), 2-(3,4-dihydroxybenzoyl)-2,4,6-trihydroxy-3(2H)-benzofuranone (2), quercetin 4‘-O-β-d-glucopyranoside (3), quercetin (5), 4‘-O-β-d-glucopyranoside of quercetin dimer (7), and quercetin dimer (8), and three novel compounds, condensation products of quercetin with protocatechuic acid (4), adduct of quercetin with quercetin 4‘-O-β-d-glucopyranoside (6), and quercetin trimer (9). These phenolic compounds were tested for their antioxidant properties using autoxidation of methyl linoleate in bulk phase or free radical initiated peroxidation of soybean phosphatidylcholine in liposomes. The flavonoid compounds having o-dihydroxy substituent in the B-ring were shown to be effective antioxidants against nonenzymic lipid peroxidation. Keywords: antioxidant; flavonoid; quercetin; lipid peroxidation; onion; Allium cepaKeywords
This publication has 10 references indexed in Scilit:
- Antioxidant Compounds from the Leaves of Peucedanum japonicum ThunbJournal of Agricultural and Food Chemistry, 2003
- Comparison of antioxidant activities of onion and garlic extracts by inhibition of lipid peroxidation and radical scavenging activityFood Chemistry, 2003
- Flavonoid Oxidation by the Radical Generator AIBN: A Unified Mechanism for Quercetin Radical ScavengingJournal of Agricultural and Food Chemistry, 2002
- Comparison of methods for the hydrolysis of flavonoids and phenolic acids from onion and spinach for HPLC analysisFood Chemistry, 2002
- Deglucosidation of Quercetin Glucosides to the Aglycone and Formation of Antifungal Agents by Peroxidase-Dependent Oxidation of Quercetin on Browning of Onion ScalesPlant and Cell Physiology, 2000
- Constituents of Amomum tsao‐ko and their radical scavenging and antioxidant activitiesJournal of Oil & Fat Industries, 2000
- Flavonoids from red onion (Allium cepa)Phytochemistry, 1998
- Iron‐catalyzed reaction products of α‐tocopherol with methyl 13(S)‐hydroperoxy‐9(Z),11(E)‐octadecadienoateLipids, 1995
- Synthesis of a phosphatidyl derivative of vitamin E and its antioxidant activity in phospholipid bilayersLipids, 1994
- Fruit, vegetables, and cancer prevention: A review of the epidemiological evidenceNutrition and Cancer, 1992