I describe the mechanism whereby ascorbic acid can hamper test systems involving a peroxide-generating system, peroxidase, and a benzidine-type indicator. In test media such as urines, abnormally high concentrations of ascorbic acid may give rise to false negatives in the determination of analytes such as glucose. Absorbance measurements in solution or reflectance measurements on commercially a...

Chemical methods for the determination of reduced ascorbic acid (Zascorbic acid) are based upon its reducing properties. The indophenol method of Bessey (1, 2) and the perinaphthindantrione hydrate method of Moubasher (3) are examples of these methods. Modifications to increase the specificity of the indophenol method have been presented by Robinson and Stotz (4), Lowry, Lopez, and Bessey (5), ...

OBJECTIVES The use of colistin in the treatment of life-threatening Gram-negative infections is associated with a high rate of nephrotoxicity that is dose limiting. This study aimed to examine the nephroprotective effect of ascorbic acid against colistin-induced nephrotoxicity. METHODS Rats were treated intravenously twice daily with saline, colistin (cumulative dose of 36.5 mg/kg), a combina...

Ascorbic acid synthesis in the pig occurs at mid-pregnancy, but activity of the enzyme l-gulono-gamma-lactone oxidase (GLO) declines thereafter during gestation and remains low when the pig nurses the sow. During late gestation the ascorbic acid concentration in the fetus increases, but serum and liver ascorbic acid concentration in the sow declines without affecting the dam's liver GLO activit...

Human tumors may contain high concentrations of ascorbic acid, but little is known about how they acquire the vitamin. Certain specialized cells can transport ascorbic acid directly through a sodium ascorbate cotransporter, but in most cells, vitamin C enters through the facilitative glucose transporters (GLUTs) in the form of dehydroascorbic acid, which is then reduced intracellularly and reta...

OBJECTIVES To study effects of hypochlorous acid (HOCl) on equine colonic mucosa in vitro, and determine whether addition of ascorbic acid protects against the effects. ANIMALS 6 healthy horses and ponies. PROCEDURE Short-circuit current was measured in mucosa mounted in Ussing chambers. Incubation conditions were: control (no additions); 5 mM HOCl; 1 mM HOCl; same and 5 mM ascorbic acid; 3...

Ascorbic acid in aqueous humor of the eye has a role as an antioxidant in delaying cataract formation. In a cross-sectional comparative study, ascorbic acid levels from aqueous humor and venous blood obtained from patients with cataracts in mountainous regions (1,300-2,000 meters) and subtropical lowlands (<100 meters) of Nepal were measured spectrophotometrically with the objective of comparin...

Purpose: To determine the effect of the temperature of water used for the preparation of paracetamol and ascorbic acid mixture on its stability, as well as to assess the influence of humidity on the stability of single components and their mixtures. Methods: The stability of the mixtures in aqueous medium was evaluated with the aid of UV–Vis spectrophotometer interfaced with a computer. Spectra...

The recent finding shows that the ascorbate involves in gamete protection and tissue remodelling. The damage of gametes by free radicals prevented by ascorbic acid and on the whole the preliminary exploration of the ascorbic acid involves directly or indirectly in fertilization or its interrelated actions. Twenty-three females, aged between 18 and 40 years, were recruited for the study. Subject...

the sulphated form of ascorbic acid may play a role in the maintenance of connective tissue, suggested that although 35S-labelled glycosaminoglycans are formed in the presence of ascorbic acid 2-[35S]sulphate, they are not formed by direct transfer of the sulphate moiety from ascorbic acid 2-[35S]sulphate but by a decomposition product of the ester (Shapiro & Poon, 1975). The role of ascorbic a...