Behavior of 3,4-endiol form of 2,3-diketo-gulono-delta-lactone formed from dehydro-L-ascorbic acid in deoxygenated and neutral solution

• Published in: Journal of Nutritional Science and Vitaminology 1989, Vol.35(1), pp.61-70
• Main Authors: Takagi, M. (Osaka Prefectural Univ., Sakai (Japan). Coll. of Agriculture), Kawajiri, A, Nakata, K, Morita, N
• Format: Article
• Language: English
• Subjects: 2, 3-diketo-L-gulonic acid; 2,3-Diketogulonic Acid - analogs & derivatives; 2,3-Diketogulonic Acid - metabolism; 2,3-Diketogulonic Acid - pharmacology; 3, 4-en-diol form of 2, 3-diketo-gulono-δ-lactone; ACIDE ASCORBIQUE; ACIDE LINOLEIQUE; ACIDO ASCORBICO; ACIDO LINOLEICO; ASCORBIC ACID; Ascorbic Acid - analogs & derivatives; Chromatography, High Pressure Liquid; dehydro-L-ascorbic acid; Dehydroascorbic Acid; Hydrogen-Ion Concentration; isomeri-zation of oxidized AsA; ISOMERISATION; ISOMERIZACION; ISOMERIZATION; LINOLEIC ACID; Lipid Peroxidation - drug effects; Magnetic Resonance Spectroscopy; Oxidation-Reduction; reduction of DHA; Solutions; Sugar Acids - metabolism; suppression of linoleic acid peroxidation
• ISSN: 0301-4800; 1881-7742
• DOI: 10.3177/jnsv.35.61

The formation of L-ascorbic acid (AsA) was observed when dehydro-L-ascorbic acid (DHA) was dissolved in neutral buffer solutions under N2 bubbling at room temperature. The reduction of DHA was done with the lactonized compound of 2, 3-diketo-L-gulonic acid (DKG), that is, the 3, 4-endiol form of 2, 3-diketo-gulono-b-lactone (3, 4-End DKGL). 3, 4-End DKGL was formed from DHA or DKG (yield about 10%) under N2 bubbling in neutral buffer solution (pH 7.2). This material was not stable in neutral or alkaline solutions. 3, 4-End DKGL suppressed more strongly the linoleic acid (LA) peroxidation in the medium containing 20% EtOH and 10mM LA than did AsA. This may suggest the possibility that 3, 4-End DKGL reproduces AsA from DHA in physiological status.