Abstract
5.6 mg of thiamine sulfuric acid ester was given to rats intraperitoneally or orally and the excretion of thiamine and its sulfuric acid ester in 24 hours' urine was separately estimated by the method proposed by us. The average value in the intraperitoneal dosage was 0.47 mg of thiamine and 4.76 mg of its sulfuric ester, and that in the oral dosage was 0.06 mg of thiamine and 0.38 mg of its sulfuric ester. The value as free thiamine was about one-tenth of its sulfuric ester value : this would be due to the fluorescence of thiochrome sufuric acid ester dissolved into isobutanol. Thiamine sulfuric acid ester was identified by paper partition chromatography in the urine after its BaCl_2-treatment. Thus thiamine sulfuric acid ester was excreted almost completely without its hydrolysis into thiamine on intraperitoneal dosage.
