Selenium-ascorbic acid interaction

The synergistic effect observed in the presence of all three antioxidants implies that there is an interaction between the individual antioxidant components. The direct interaction of the a-tocopherol radical and ascorbic acid is already well established (Bisby and Parker 1995) and a study by Mayne and Parker (1989) on chicks deficient in vitamin E and selenium showed that the... 

Vijayakumar et al. [69] has described a method for the determination of trace quantities of selenium in plant tissues based on the interaction of selenium(IV)-iodine with an acid medium, leading to the liberation of iodine. This method was utilised for the indirect determination of selenium by AA spectrophotometry. The iodine is extracted into benzene and subsequently reductively stripped into an aqueous solution of ascorbic acid. After the extrac-... 

In the diet and at the tissue level, ascorbic acid can interact with mineral nutrients. In the intestine, ascorbic acid enhances the absorption of dietary iron and selenium reduces the absorption of copper, nickel, and manganese but apparently has little effect on zinc or cobalt. Ascorbic acid fails to affect the intestinal absorption of two toxic minerals studied, cadmium and mercury. At the tissue level, iron overload enhances the oxidative catabolism of ascorbic acid. Thus, the level of dietary vitamin C can have important nutritional consequences through a wide range of inhibitory and enhancing interactions with mineral nutrients. 

Very fundamental involvements of ascorbic acid have been presented, such as its role in the regulation of gene expression or in cell growth and tissue culture. For example, the effects of ascorbic acid on the expression of type I and X collagen genes have been considered. Interactions between ascorbic acid and other redox active micronutrients (vitamin E and selenium) have been discussed. An understanding of the fundamental roles of ascorbic acid will provide a rationale for the biomedical implications of this essential nutrient. 

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