The metabolic fate of l-ascorbic acid-1-(14)C and -6-(14)C has been investigated in two species in two genera of Vitaceae. Results suggest that ascorbic acid metabolism in the Vitaceae involves splitting the 6-carbon chain into 4- and 2-carbon fragments. The former, corresponding to C1 through C4 of ascorbic acid, is further oxidized to tartaric acid while the latter, corresponding to C5 and C6...

in this work, an optical sensor for detection of ascorbic acid is described. the sensor is fabricated by casting and spin-coating silica sol-gel doped with 2,6-dichlorophenol indophenol on the glass plates. the sols are in turn obtained by acidic hydrolysis of various precursors such as tetraethoxysilane, triethoxymethylsilane and triethoxyoctylsilane in the presence of 2,6-dichlorophenol indop...

CONTEXT Some animal studies suggest that orally administered ascorbic acid may chelate lead and decrease the risk of the toxic effects of lead. However, results from several small studies in humans have yielded inconclusive evidence of a beneficial effect of ascorbic acid on lead toxicity. OBJECTIVE To examine the relationship between serum ascorbic acid levels and prevalence of elevated bloo...

Rapid separation and determination of mixtures of L-ascorbic acid, nitrite, sulfite, oxalate, iodide and thiosulfate by conventional ion chromatography is often difficult due to incomplete separation of L-ascorbic acid and nitrite from the water peak when using eluents giving short elution times for iodide and thiosulfate. Separation of the six species within about 15 min has been achieved by i...

The ACh-releasing factor, which is required for ACh release in presence of 2 mM ATP, 2 mM Mg and 10(-5) M Ca from isolated synaptic vesicles, was purified from the synaptosomal cytoplasm of rat brain by Sephadex G-15, DEAE-Sephadex, Sephadex G-10 and AG50W-2X column chromatographies and identified as ascorbic acid. A low concentration of L-ascorbic acid (5 x 10(-6) M) produced a release of ACh ...

As the initial step in the use of fibroblasts as a model system for 'in situ kinetics', ascorbic acid (vitamin C) accumulation in normal human fibroblasts was investigated for the first time. Ascorbic acid was transported into fibroblasts and accumulated against a concentration gradient up to 20-fold, as measured by h.p.l.c. with coulometric electrochemical detection. Ascorbic acid accumulation...

The experiments of Sealock et al. (l-3) and of Levine et al. (4) have given reasons for believing that one of the functions of ascorbic acid in the animal body is to facilitate the metabolism of L-tyrosine and L-phenylalanine. Sealock and Silberstein (2) showed that the administration of tyrosine orally to scorbutic guinea pigs resulted in the excretion of metabolites containing the benzene rin...