Incorporation of L-dehydroascorbic acid (DAsA) into human erythrocyte proceeded very rapidly, attaining equilibrium within one minute. Appreciable portions of DAsA incorporated into erythrocyte were converted into ascorbate and L-2,3-diketogulonic acid (DKG) in vivo. During the incorporation experiments at 37℃, DAsA in the test solution (isotonic phosphate buffer, pH 7.4) changed rapidly into DKG. The conversion, however, occurred hardly at 10℃. Human erythrocyte uptook DAsA until the intracelluar level reached the same level as that in the test solution. The incorporation rate of DKG into erythrocyte was very low.

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The antiscorbutic activity of ascorbic acid 2-sulfate (AsS) in young male of hartley guinea pigs fed the vitamin C-deficient diets has been investigated. The animal were diyided into five groups : 1) addition of 0.1mmol ascorbic acid (AsA)/animal/day, 2) addition of 0.1 mmol AsS/animal/day, 3) addition of 0.2mmol AsS/animal/day, 4) addition of 0.5mmol AsS/animal/day, and 5) control-no supplement, the feeding test were carried out for five weeks. In this experiment, AsS would be difficult to prevent the scurvy in the guinea pig. Change of vitamin C contents in tissues and blood of guinea pigs were followed for 16 days as the second experiment. The animals were divided into four groups, and supplemented with the following : 1) 0.1mmol AsA/animal/day, 2)0.5mmol AsS/animal/day, 3) 1.0mmol AsS/animal/day, and 4) control-no supplement. The vitamin Clevels of liver, kidney and blood in AsS-treated animals were similar to those of scorbutic animals. These investigation has shown that AsS is devoid of antiscorbutic activity in the guinea pig.

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Changes in the concentration of pyridoxal (PAL) and pyridoxal phosphate (PALP) in sera of human subjects with alcohol habits were investigated after loading pyridoxine HCl (PIN・HCl) before and after administration of PIN・HCl. Twenty mg of PIN・HCl was orally given to 7 control subjects; 7 volunteers with alcohol habits and 6 patients with alcohol intoxication, twice a day lasting for 14 days. On the 14th day, fasting blood was taken from subjects in each 3 groups at 1,2,3 hours after loading 10mg of PIN-HCl. The concentration of PAL and PALP in sera revealed no significant difference between 3 groups before loading PIN・HCl. After first loading, PAL in sera was apparently increased and remained the increasing level up to 2 hours in the volunteers and the patients (p<0.05), however PALP-level rernained unchanged. On the 14th day, the concentration of PALP in fasting sera were increased in both groups of controls and patients (P<0.05) but remained unchanged in volunteers with alcohol habits. After loading PIN・HCl, PALP-level were increased also in the volunteers inspite of daily intake of alcohol. There were some evidence suggestive of the presence of a latent vitamin B_6 deficiency in the subjects habiting daily intake of alcohol. The concentration of serum triglycerides, phospholipids and total cholesterol were changed in both of the volunteers and the patients but unchanged in controls after administrating PIN・HCl. Changes in the activities of GOT, GPT, γ-glutamyltranspeptidase and alkaline phosphatase and the contents of blood sugar were remained within normal range before and after loading and administering PIN・HCl in all three groups.

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