Erythorbic acid antioxidant
June 26 2015 by
Ray Sahelian, M.D.

Erythorbic acid is a stereoisomer of ascorbic acid with similar properties. It is widely used as an antioxidant in processed foods. Little human research has been published regarding its supplementation.

Studies
Food Chem. 2013. Sensorially important aldehyde production from amino acids in model wine systems: impact of ascorbic acid, erythorbic acid, glutathione and sulphur dioxide. The efficiency of different white wine antioxidant systems in preventing aldehyde production from amino acids by oxidative processes is not well understood. The aim of this study was to assess the efficiency of sulphur dioxide alone and in combination with either glutathione, ascorbic acid or its stereoisomer erythorbic acid, in preventing formation of the sensorially important compounds methional and phenylacetaldehyde from methionine and phenylalanine in model white wine. UHPLC, GC-MS/MS, LC-MS/MS, flow injection analysis and luminescence sensors determined both compositional changes during storage, and sulphur dioxide-aldehyde apparent equilibrium constants. Depending on temperature (25 or 45C) or extent of oxygen supply, sulphur dioxide was equally or more efficient in impeding the production of methional compared to the other antioxidant systems. For phenylacetaldehyde, erythorbic acid or glutathione with sulphur dioxide provided improved inhibition compared to sulphur dioxide alone, in conditions of limited oxygen consumption. The results also demonstrate the extent to which sulphur dioxide addition can lower the free aldehyde concentrations to below their aroma thresholds.

Erythorbic acid is a potent enhancer of nonheme-iron absorption.
Am J Clin Nutr. 2004. Institute of Food Science and Nutrition, Swiss Federal Institute of Technology, Zurich, Rueschlikon, Switzerland.
The aims of the present study were to evaluate the effect of erythorbic acid on iron absorption from ferrous sulfate at molar ratios of 2:1 and 4:1 (relative to iron) and to compare the effect of erythorbic acid directly with that of ascorbic acid at a molar ratio of 4:1. Iron absorption from iron-fortified cereal was measured in 10 women on the basis of erythrocyte incorporation of stable iron isotopes ((57)Fe or (58)Fe) 14 d after administration. Each woman consumed 4 ferrous-sulfate-fortified test meals (containing 5 mg Fe/meal) with or without added erythorbic or ascorbic acid. The data were evaluated by use of paired t tests, and the results are presented as geometric means. Iron absorption from the test meal without any added enhancer was 4%. The addition of erythorbic acid (at molar ratios of 2:1 and 4:1 relative to iron) increased iron absorption 2.6-fold and 4.6-fold, respectively. The addition of ascorbic acid (molar ratio of 4:1) increased iron absorption 2.9-fold. At a molar ratio of 4:1, erythorbic acid was 1.6-fold as potent an enhancer of iron absorption as was ascorbic acid. Although erythorbic acid is a potent enhancer of iron absorption, its lack of antiscorbutic activity limits its usefulness in iron-fortification programs. However, it may play a major role in enhancing iron bioavailability from mixed diets that include foods preserved with erythorbic acid.

Effect of smoking on erythorbic acid pharmacokinetics.
Br J Nutr. 2003. Department of Pharmacology and Pathobiology, Royal Veterinary and Agricultural University, Copenhagen, Denmark.
Smoking significantly lowers the concentration of plasma antioxidants. Acorbic acid has recently been shown to be depleted by smoking per se. However, the direct cause of ascorbate depletion remains unclear. Erythorbic acid is a stereoisomer of ascorbic acid commonly used as antioxidant in foodstuffs and has the same redox properties as ascorbic acid. We therefore investigated if erythorbic acid could be used as a non-isotopic marker of smoking-induced oxidative stress. In a sample of smokers (n 10) and non-smokers (n 10), the pharmacokinetics of erythorbic acid were followed after a single oral dose (1 g) and subsequently, the effect of a 2-week ascorbic acid supplementation (0.5 g/d) on erythorbic acid kinetics was studied in a double-blind, placebo-controlled fashion. Our present results do not suggest that altered pharmacokinetics is likely to play a major role in the ascorbic acid depletion consistently observed in smokers.