Ascorbic Acid Dehydroascorbic Acid C6 Dicarboxylic Acid
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چکیده
Dehydroascorbic acid is shown to be converted to 2-(threo-l,2,3-trihydroxypropyl)tartronic acid in aqueous alkaline solutions. The structure of the acid was determined by mass spectrometry of its acyclic Me3Si derivative. Mass spectrometric and chromatographic data are compared with those of related compounds. The acid is formed by a benzilic acid rearrangement of the intermediate 2,3-hexodiulosonic acid. The rate of formation at 38°C was studied quantitatively by GC. It increases at increased alkalinity but is significant even at physiological pH. The presence of oxygen does not substantially influence the reaction.
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Antiviral effects of ascorbic and dehydroascorbic acids in vitro.
In the present study, ascorbic acid weakly inhibited the multiplication of viruses of three different families: herpes simplex virus type 1 (HSV-1), influenza virus type A and poliovirus type 1. Dehydroascorbic acid, an oxidized form of ascorbic acid and hence without reducing ability, showed much stronger antiviral activity than ascorbic acid, indicating that the antiviral activity of ascorbic...
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It was previously reported by the authors (1) that, as long as pyruvate exists in the medium containing E. coli K12, dehydroascorbic acid is reduced , and this re ducing activity is dependent upon a pyruvate oxidase system. The presence of the mechanism of reducing dehydroascorbic acid into ascorbic acid in the bacterial cells would serve the regulation of ascorbic acid, protecting its decompos...
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