Ascorbic acid overload and vitamin B6 deficiency have been implicated in the development of hyperoxalemia in dialysis patients, but there is still disagreement about this. Hemodialysis patients who are exposed long-term hyperoxalemia may develop secondary oxalosis with an increased risk of cardiac, vascular, and bone disease, and thus may benefit from maintaining a low serum oxalic acid level. ...

a flow injection method is reported for the determination of ascorbic acid based on amperometric detection, using a cobalt(ii) phthalocyanine (copc) modified graphite-epoxy electrode. the amperometric respons was evaluated with regard to ph, ionic strength of the electrolyte, flow rate of the carrier solution, injected sample volume and conditioning time of the electrode. the limit of detection...

A xanthine oxidase enzyme electrode (xanthine oxidase immobilized on electrochemically modified graphite and conveniently coated with gelatine electrode working surface) for quantitative analysis of xanthine is proposed. The detection of thus developed electrochemical system is based on the electroreduction of hydrogen peroxide generated in enzyme layer and offered L-ascorbic and uric acid redu...

A simple, sensitive and interference-free method was proposed for the determination of arsenic, based on the generation of volatile arsenic trichloride coupled with atomic fluorescence spectrometry. Thiourea, together with l-ascorbic acid, was used to reduce As(V) to As(III), and the chloride generation was based on the reaction between As(III) and hydrochloric acid. Under the optimized experim...

Methods based on the ability of ascorbic acid to reduce the dye 2:6-dichlorophenolindophenol (indophenol) to a colourless compound (Tillmans, Hirsch & Reinshagen, 1928) have been widely used in the estimation of ascorbic acid. Many other substances, including thiol compounds, thiosulphates, hydrogen sulphide, polyphenols and reductones (Lugg, 1942; Harris & Mapson, 1947) also decolorize indophe...

The biosynthesis of i-ascorbic acid (vitamin C) is not well understood in plants. The ozone-sensitive Arabidopsis thaliana mutant vifamin cl (vfcl; formerly known as sozl) is deficient in ascorbic acid, accumulating approximately 30% of wild-type levels. This deficiency could result from elevated catabolism or decreased biosynthesis. No differences that could account for the deficiency were fou...

heat stress (hs) often blamed for suboptimal reproductive efficiency and is a worldwide problem, which inflicts heavy economic losses reflected in limiting the breeding season of rabbits to be normally from september to may in northern hemisphere and subtropical regions. the present experiment was conducted to study the effect of summer heat stress and the alleviating effect of some antioxidant...