Euglena gracilis was found to contain a peroxidase that specifically requires L-ascorbic acid as the natural electron donor in the cytosol. The presence of an oxidation-reduction system metabolizing L-ascorbic acid was demonstrated in Euglena cells. Oxidation of L-ascorbic acid by the peroxidase, and the absence of ascorbic acid oxidase activity, suggests that the system functions to remove H20...

Corresponding Author Email : [email protected] The study evaluated effect of ascorbic acid and citric acid treatments on the functional and sensory properties of yam flour. Yam (Dioscorea rotundata) tubers were washed, peeled and cut into thin slices of 1cm thickness. The slices were divided into 7 portions. The 1st portion served as control. The 2nd, 3rd, 4th and 5th portions were soaked i...

The effect of ascorbic acid on the monophenolase activity of tyrosinase, using tyrosine as substrate, has been studied. Over the ranges of ascorbic acid concentration used, no direct effect on the enzyme is found. However, a shortening of the characteristic induction period of the hydroxylation reaction is observed. The evolution of the reaction is dependent on the concentration of ascorbic aci...

Background: Exposure to ionizing radiation results in genotoxicity and the unrepaired lesions in cellular DNA results in cell cycle arrest, reproductive death, interphase death, division delay, chromosome aberrations, mutations, etc. leading to the intensive destruction of cells and violation of their proliferative capacity there by adversely affecting the mammalian system. Since ionizing radia...

Background: The most devastating manifestations of diabetes mellitus are vascular complications. Although there are many factors involved in the pathogenesis of diabetic vasculopathy, many studies suggest a role for glucose–induced oxidative stress. Studies in animal models, have demonstrated that the administration of antioxidants restores normal endothelial functions. The study was designed t...

Though horses synthesize ascorbic acid in their liver in amounts that meet their needs under normal circumstances, prolonged stress results in low plasma concentrations due to enhanced utilization and renal excretion and can reduce immune function. It was hypothesized that plasma ascorbic acid could be maintained in weanling horses by oral supplementation following prolonged transportation. Wea...

Ascorbic acid and fructose react in an aqueous alkaline solution at temperature below 50°C in a Maillard-type reaction to from brown coloured end products. The kinetics of browning of alkaline solution of fructose in presence of ascorbic acid has been studied by measuring the absorbance of browning development in the reaction. The development of brown colour due to heating of either reducing su...

Recommended daily allowances, U.S.A., for ascorbic acid are several times the minimum daily requirement of about 10 mg to prevent clinical symptoms in adults. The recommended daily allowances reflect the levels of ascorbic acid required to produce tissue saturation in human beings, so that higher doses are promptly excreted in the urine. In various investigations, responses to ascorbic acid wer...

The influence of exogenous ascorbic acid (0.5 mM) in counteracting NaCl-induced cellular alteration of onion bulb inner epidermis was investigated. Plasma membrane permeability, protoplasm swelling and cell viability were measured under the effect of 150 mM NaCl in presence and absence of ascorbic acid. Ascorbic acid was added simultaneously with salt or before salt treatment. Salt stress at 15...

In this study, a new reaction system for quantitative determination of ascorbic acid was introduced. The developed method is based on inhibitory effect of ascorbic acid on the Orange G-bromate system. The change in absorbance was followed spectrophotometrically at 478 nm. The dependence of sensitivity on the reaction variables including reagents concentration, temperature and time was investiga...