1. The oxidation of Palmitate in rat liver intact mitochondria of the alcohol fed group was found to be lower than that of the control group. However, the oxidation of acetate in intact mitochondria of the alcohol fed group was found to be almost the same as that of the control group. As for the oxidation of palmitate in sonicated mitochondria, no difference was found between the alcohol fed group and control group.
2. The stimulatory effect of carnitine on the oxidation of both palmitate and acetate in intact mitochondria, and on the oxidation of palmitate in sonicated mitochondria were diminished in the alcohol fed group.
3. The administration of alcohol to rat was found to have some pathological effect on carnitine barrier site of mitochondrial membrane.

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With a view to study the changes in collagen and nucleic acids content of skins and granulomas due to vitamin B₁₂ deficiency, two groups of weanling albino rats were fed for six weeks with the vitamin B₁₂ deficient and supplemented diets respectively and another two groups were raised under similar conditions for inducing granulomas by cotton sponge implantation technique. The analyses of skins, granulomas, urine and plasma showed that neutral saltsoluble collagen, insoluble collagen and RNA and DNA contents of skins and granulomas, the urinary excretion of both bound and free hydroxyproline and the free hydroxyproline content of plasma were all significantly decreased in the vitamin B₁₂ deficient animals compared to the supplemented group. These results collectively show that the synthesis of collagen in skins and granulomas was appreciably decreased in the vitamin B₁₂ deficient group. The analyses of skins further showed that the percent reversibility of gel and α₁- and α₂-chains of neutral salt-soluble collagen appreciably increased, β₁₁- and β₁₂-chains and aldehyde content of the neutral salt-soluble collagen significantly decreased in the vitamin B₁₂ deficient animals, which indicated that the intra-molecular crosslinking of collagen was also impaired.

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Following the intraperitoneal injection of an aqueous dispersion of ³H-retinyl acetate into weanling rats, autoradiographic techniques were used to visualize the location in skin and its appendages of radioactivity derived from the labeled retinyl acetate. Ordinary autoradiographs, for location of labeled substances bound to tissue components, showed the presence of radioactivity in cells of the sebaceous glands and in the epidermis. Soluble-compound autoradiographs, for location of both bound and soluble labeled materials, showed essentially the same results as the ordinary autoradiographs with perhaps a somewhat greater concentration of radioactivity seen in the sebaceous glands in the soluble-compound autoradiographic preparations.

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The enzyme preparations obtained from acetone powders of 5 kinds of green leaves contained the enzyme system responsible for the synthesis of thiamine from pyrimidine (2-methyl-4-amino-5-hydroxymethylpyrimidine) and thiazole (4-methyl-5-β-hydroxyethylthiazole) moieties. The condensation reaction of the moieties was dependent upon the presence of ATP and Mg²⁺. The enzyme preparations showed the optimal activity at around pH 7.5 and lost its activity abruptly beyond 48°.
The rate of thiamine synthesis increased with the increase of ATP concentration and reached an optimum. Beyond the optimum, the rate decreased as ATP concentration increased. The additional Mg²⁺ not only accelerated the rate but also partially removed the inhibition by ATP. In addition to Mg²⁺, Mn²⁺ and Co²⁺ also activated the thiamine synthesis.

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Intraperitoneal as well as oral administration of pyridoxine 50mg per 100g body weight to rats resulted in a 2 to 3-fold rise of hepatic tyrosine transaminase (L-tyrosine 2-oxoglutarate aminotransferase EC 2.6.1.5.), the maximal activity being attained 4 hours after administration. This rise was also observed by intraperitoneal injection of some other vitamins.
Bilateral adrenalectomy curtailed the rise by pyridoxine or pyridoxal administration but still a 150% increase of the activity was observed 2 to 4 days after the operation, while injection of pyridoxamine and other vitamins had no effect on the adrenalectomized rats. The induction of tyrosine transaminase by vitamin B₆ derivatives, which was confirmed by Kenney et al. due to an increased rate of its de novo synthesis, was no more seen 7 days after adrenalectomy. The inducibility was restored by the pretreatment of hydrocortisone 5mg per 100g body weight of rats 15 hours before the injection of pyridoxine.
This phenomenon together with the fact that the day course of the induction by pyridoxine after adrenalectomy seems to reflect the serum content of corticosterone of adrenalectomized rats as reported by Fazekas, supports the conclusion that the induction of tyrosine transaminase by pyridoxine is a secondary change mediated by glucocorticoid.

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The effect of ascorbic acid on the hydroxylase and dehydrogenase activities was studied in vivo to clarify its role in the biological oxidation. Tyrosine hydroxylase and tryptophan-5-hydroxylase which require 2-amino-4-hydroxy-6, 7-dimethyltetrahydropteridine (DMPH₄), NADP and molecular oxygen were investigated with the non-scorbutic and scorbutic guinea pigs. Several dehydrogenases such as glucose-6-phosphate dehydrogenase, isocitrate dehydrogenase and malic enzyme, which require no molecular oxygen but NADP, were also studied by comparing the activities in the non-scorbutic guinea pig with those in the scorbutic guinea pig. The results indicated that the activities of tyrosine hydroxylase and tryptophan-5-hydroxylase of the adrenal gland, liver and brain of the nonscorbutic guinea pig were higher than the values found in the scorbutic guinea pig, although no significant change in the activity of dehydrogenase was observed in the tissues of the non-scorbutic and scorbutic guinea pigs.

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Changes in biotin and total folic acid activities in tempeh during fermentation with Rhizopus oljgosporus were investigated. It was found that contents of biotin and total folate compounds in tempeh were 2.3 and 4-5 times higher than those in unfermented soybeans, respectively.

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Riboflavin synthetase, which catalyzes formation of the vitamin from 6, 7-dimethyl-8-ribityllumazine, was purified about 700-fold from an extract of spinach by two separate procedures of the followings; (1): extraction with a phosphate buffer, the first fractionation with ammonium sulfate, protamine sulfate treatment, the second fractionation with ammonium sulfate, treatment with CM-cellulose, and two-time chromatographies on DEAE-cellulose, and (2): extraction with a phosphate buffer, two-time ammonium sulfate precipitations, and chromatographies on DEAE-cellulose and on DEAE-Sephadex. The specific activities of the first and second enzyme preparations were of 15.1 and 16.2 mμmoles riboflavin formed per hour per mg protein at 37°, respectively. The purified enzyme retained initial activity at 0-4° for 24 hours, and was stable for one week at 0-4° under the saturation with ammonium sulfate. Freezing caused complete loss of the activity. Cysteine, ascorbate and Na₂SO₃ protected the enzyme against the inactivation. The optimal activity was exhibited at pH 7.5. The apparent activation energy was 15, 000 calories per mole between 45° and 25°. Michaelis constant was calculated as 4.5×10^-5M at pH 7.5. Acetate, acetylacetone, acetoine, glucose, succinate, malonate, glycollate, oxalate, threonine and glycine (10^-2M each) did not influence the reaction rate. But, glyoxal and pyruvate (10^-2M each) was markedly inhibitory. Ascorbafe, cysteine and Na₂SO₃ enhanced the rate. p-Chloromercuribenzoate, HgCl₂ and CuSO₄ (10^-3M each) blocked completely the reaction. KCN, EDTA, o-phenanthlorine and 8-hydroxyquinoline (10^-3M each) had no effect on the rate. Stoichiometry of the reaction was determined by spectrophotometry: one molecule of the vitamin was yielded from two molecules of the substrate.

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The gas chromatographic conditions for the assay of vitamins D were described. The analysis was performed on Shimazu Gas Chromatograph GC-4AP equipped with a hydrogen flame ionization detector. Glass columns (4 i.d.×1000mm) packed with 1.5% OV-17 on Shimalite W, 80-100 mesh, silanized, were operated at 240° and a flow rate of 40ml/min (N₂) was maintained. Adoption of “unmodified” D as an analytical form and good GLC resolution under the operated condition made the procedure more simple and time-saving. Employment of 7-dehydrocholesteryl acetate as an internal standard enhanced the accuracy of the analysis. Satisfactory result was obtained in the determination of vitamins D₂ and D₃ in mixtures.

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Reaction of riboflavin 2′, 3′, 4′, 5′-tetrabutyrate (R-BUT) with linoleic acid (or methyl linoleate) under ultra violet light irradiation was investigated. The formation of linoleic acid peroxide was markedly repressed in the presence of R-BUT. Absorbance at 447mμ of R-BUT dissolved in linoleic acid decreased by ultra violet light irradiation, but partially recovered by standing the irradiated solution in the dark. Since this recovery was limited to some extent, at least two processes, viz. reversible and irreversible processes, are considered to exist. The reversible decrease in absorbance at 447mμ of R-BUT could be attributed to the photoreduction of riboflavin part of R-BUT. The irreversible decrease of absorbance at 447mμ is probably due to the decomposition of the isoalloxazine nucleus of R-BUT caused by the reaction with linoleic acid in the process of its peroxide formation. The formation of linoleic acid peroxide upon aeration in the dark was also repressed by R-BUT.

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