Utilizing Trendelenburg's as well as Magnus' method, the influence of thiamine tetrahydrofurfuryl disulfide (TTFD) upon the movement of the isolated small intestine of guinea pigs, rabbits, cats and dogs was studied. The results were summarized as follows:
1. At the concentration of 5×10^-5g/ml TTFD produced on the one hand a lowering of the tone, prolongation of the period of rhythmic contraction waves and on the other hand a remarkable increase of the amplitude of the waves.
2. After the administration of atropine the excitatory effect of TTFD was reversed to the inhibitory.
3. After successive administrations of atropine and C₆ no action of TTFD was marked.
4. TTFD always had an excitatory effect upon the motility of the intestinal strip prepared from the animal which had been treated with reserpine.
5. TTFD had no effect on the small intestine isolated from cats treated with reserpine and atropine.
6. From the results described above it may be concluded that TTFD exerts an excitatory action upon both the excitatory and inhibitory neurones residing in Auerbach's plexus, whereas it exerts no action upon the intestinal muscle. It could be considered that the effects described in (1) were the results of a mutual coordination of the function of two kinds of the neurones described above.

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1. Enzymatic formation in vitro of vitamin D₂ sulfate by various animal tissues was studied and the biosynthesis of the sulfate was proved by using the rat-liver homogenate.
2. Chemical synthesis of ammonium vitamin D₂ sulfate was performed and some physicochemical properties were reported.
3. Vitamin D₃ sulfate was also isolated from rabbit urine after oral administration of vitamin D₃. It was in agreement with the synthesized sample.

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1. The distribution of vitamin D sulfate in animal tissues was studied. Considerable amounts of the sulfate were formed in the liver, but extremely poor in other tissues.
2. Vitamin D-sulfokinase was isolated from rat-liver homogenate, and the optimum conditions were investigated.
3. Isotopic investigation for the biogenesis of vitamin D sulfate was carried out using the vitamin D-sulfokinase preparation.
The activity of the vitamin D₂-sulfokinase preparation obtained by the authors was estimated to be 3.3% as estimated from the yield of vitamin D₂ sulfate from the vitamin D₂ employed.

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1. Metabolic activity of inosine on the incorporation of riboflavin into rat-liver xanthine oxidase system was studied.
2. The effect of ingested inosine on liver nitrogen was scarcely recognized.
3. The tendency of the increase in total riboflavin and flavin mononucleotide in the liver of the rats receiving inosine was observed, but the change in the contents of free riboflavin and flavin-adenine dinucleotide was not observed.
4. The tendency of the increase in the activity of liver xanthine oxidase in the rats receiving inosine was observed.

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1. Concerning the growth-stimulating effect of fresh beef liver on rainbow trout fingerlings, the metabolism of ingested amino acids in the liver was studied and successively the occurrence of vitamin A-protein-complex in the liver was tested by electrophoresis, but no positive results were obtained.
2. Halver's vitaminological aspect of fresh liver as a high vitamin diet was investigated but no possible confirmation could be obtained.
3. The enzymatic fractionation using sucrose was tested and the fraction soluble in 45 per cent sucrose solution was found most effective as the growth-promoting factor for rainbow trout fingerlings. Repeated investigations showed that the active principle of fresh liver for the fish fingerlings might be chiefly due to various vitamin-dependent enzyme systems.

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Absorption of vitamin B₁₂ from the proximal jejunum was studied and compared with that of albumin in man employing a three lumen tube with an inflatable balloon. A test solution containing physiological doses of radioactive cyanocobalamin (Co⁵⁷, Co⁶⁰) or I¹³¹-human albumin and bromsulfalein (BSP) as an unabsorbable reference, was instilled in the upper jejunum and the decrease of B₁₂:BSP or I¹³¹:BSP was determined in the fluid withdrawn at intervals. It was found that absorption of B₁₂ was minimal during the test period of three hours, whereas I¹³¹-human albumin was absorbed quickly and to a much greater extent. After drainage and washing of the jejunum at the end of the test, infusion of EDTA released B₁₂ further and increased the B₁₂:BSP ratio in about one half of the test subjects, and the results of Schilling test carried out then were consistent with the finding.

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Several excellent solvents for the thin-layer chromatography (TLC) of vitamin B₁₂ and the related compounds were found out using Aluminium oxide G, Kieselgel G and Kieselguhr G as inorganic adsorbents, and P-cellulose as well as DEAF-cellulose as organic ones. Since there are many vitamin B₁₂ factors of similar Rf values, it is still difficult to separate each factor in the mixture completely and identify it. It is advisable to prepurify or fractionate prior to the TLC of vitamin B₁₂.

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It has been established that glycollate is oxydized to glyoxylate by the crystalline lactate dehydrogenase. These fiedings suggest the possibility that some single enzymatic proteins may catalyze multiple reaction.

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1. Hepatic content of CoQ decreased in rats with acute CCl₄ poisning or steroid diabetes, but it did not show any change in those with chronic CCl₄ poisoning or alloxan diabetes.
2. Most part of CoQ was found in the mitochondrial fraction. The CoQ content of liver mitocondria per wet weight decreased in CCl₄ poisoning, alloxan diabetes or steroid diabetes. The changes were parallel to the changes in succinate dehydrogenease activity in the liver.
3. CoQ of rat liver was mainly CoQ₉, but CoQ₇, CoQ₈ and CoQ₁₀ were also in a small quantity.

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1. Optical isomers of hydroxyethylthiamine (DL-, D- and L-HET), together with its two alkyl homologues, DL-hydroxypropylthiamine (DL-HPT) and DL-hydroxyisobutylthiamine (DL-HIBT), were examined for their vitamin B₁ activity, using thiamine-deficient rats and rice-birds as test animals.
2. When orally administered, in a daily dose equivalent to 10μg of thiamine, to rats which had been maintained on a thiamine-deficient diet, all these compounds showed perfect thiamine activity, bringing about immediate increase of growth rate. Their effects were indistinguishable from that of thiamine and, unexpectedly, no difference was observed between the activity of D- and L-isomers of HET.
3. To rice-birds fed a thiamine-deficient diet, each compound was orally administered in a daily dose equivalent to 3μg of thiamine. While the control birds died on the 10th and 11th days with noticeable decrease in body weight, those receiving test compounds other than DL-HIBT, as well as thiamine, remained healthy through the experimental period of 20 days. The effect of DL-HIBT, however, was less marked and three out of five died within the period.

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1. Investigation was made of the action of two types of bacterial thiaminase on α-hydroxyalkyl-2-thiamine (hydroxyethyl, hydroxypropyl and hydroxyisobutyl) and hydroxyethylthiamine propyl disulfide.
2. While hydroxyalkylthiamine was readily decomposed by thiaminase I of Bacillus thiaminolyticus Matsukawa et Misawa, it was fairly resistant to the action of thiaminase II produced by Bacillus aneurinolyticus Kimura et Aoyama.
3. Hydroxyethylthiamine propyl disulfide was remarkably resistant to both thiaminases.

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Experiments on the production of dextrans and riboflavinylglycosides from sucrose and riboflavin were carried out with various strains of Leuc. mesenteroides. It was observed that the yield of riboflavinylglycosides did not run paralled to the yield of dextrans not only in growing cultures but also in enzymic reactions, and moreover higher yields of riboflavinylglycosides were observed with such strains as to produce dextrans containing higher ratios of branching chains.

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1. Cell-free extracts prepared from strains of Leuc. mesenteroides grown on sucrose were found to reveal the production of riboflavinylglucoside from sucrose and riboflavin. Moreover, it was found that the extract utilized only sucrose as a glucosyl donor in the formation of riboflavinylglucoside, while glucose itself was quite ineffective.
2. The intracellular enzyme revealing formation of riboflavinylglucoside was isolated by ammonium sulfate precipitation from the cell-free extract of the strain NRRL B-1299 grown on sucrose.
3. Maximum activity of the enzyme was observed in the range of pH 4.5 to 5.3 and around at 30°. The enzyme was found to be fairly sensitive to heat as it was almost completely inactivated by heating at 45° for 10 minutes.
4. By the action of the enzyme, riboflavinyloligosaccharides were observed to be formed through the successive transfer of glucosyl group between riboflavin compounds and sucrose.

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