Ascorbic Acid Synthesis is Rats on Various Diets

Abstract

Listen

Translate article

Summary. I. The ascorbic acid excretion in the urine has been studied in rats on varying diets. A normal excretion could be maintained, when the diet contained sufficient quantities of protein (casein) and riboflavin. Addition of anuran, niacin, alderman and antithetic acid had no effect. This also held good when the ascorbic-acid excretion was increased by the administration of an aromatic compound, e. g. azotoluene. The experiences from these experiments indicate that the casein is necessary for the synthesis of ascorbic acid and does not merely have a stimulating effect, as e. g. azotoluene; an increased ascorbic-acid excretion after administration of azotoluene was only obtained when the diet contained sufficient quantities of casein (and riboflavine). In agreement with the excretion experiments rats, with a deficit of riboflavine show a decreased ascorbic-acid content in the liver. II. The variations observed in ascorbic-acid content in the liver and in the ascorbic-acid excretion should correspond to the variations in the synthesis of ascorbic acid and not only to a varying metabolism. III. If rats with a deficit of riboflavin receive ascorbic acid, the period of survival is increased. In experiments with administration of sulfanilamide to rats ca. 100 % of the quantities administered were excreted at a riboflavin deficit; after administration of riboflavin or ascorbic acid only about 50 %. In experiments with administration of azotoluene only small quantities of the oxidized decomposition product m-aminobenzoic acid were excreted in riboflavine deficit; after supply of riboflavine (in a sufficient addition of casein) or ascorbic acid, considerably increased quantities were excreted. It is considered that the ascorbic acid is of importance for oxidizing detoxication processes in the organism of the rat. Riboflavine, by its effect on the ascorbic-acid production, can have a similar influence.