The defatted sclerotia powder was partially hydrolyzed with dilute acid, and the material obtained was fractionated by carbon column chromatography, separated into two disaccharides, three trisaccharides and three tetrasaccharides, respectively. In these hydrolyzates, α, α-trehalose, laminaribiose, and gentiobiose were identified.

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The changes in polyphenol oxidase activity in tea leaves during black tea manufacture were investigated.
Polyphenol oxidase in the leaves was more active in summer than in spring and the tea clones for black tea had higher polyphenol oxidase activity compared with the clones for green tea.
Enzyme activity in the leaves increased gradually in the lapse of the withering period, and the higher the withering temperature was, the faster the enzyme activity increased.
The enzyme activity increased rapidly by rolling in both the high and low degree withered leaves, and reached about 2 to 3 times as much as that in the fresh leaves.
Enzyme Activity decreased along with the fermentation process after rolling, and the higher the fermentation temperature was, the larger the decrease in activity was. It was presumed that the decrease in enzyme activity during the fermentation was caused by the formation of insoluble complexes of the oxidized polyphenols and the enzyme protein.

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The transglucosidation action of Schizosaccharomyces pombe α-glucosidase has been in-vestigated by paperchromatography.
The enzyme sythesized some oligosaccharides, consisting mainly of isomaltose, together with panose, isomaltotriose, nigerose, kojibiose and maltotriose by transferring glucosyl moiety from maltose. A small amount of isomaltose was also formed even from free glucose.
The transglucosidation mechanism of the enzyme and the process of the further con-verison of the transglucosidation products were examined. The data indicated that the transglucosidation action of Schizosacch. pombe α-glucosidase also was similar to those of mould α-glucosidase.

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Some strains of Pseudomonas was found capable of utilizing L-theanine or D-theanine as a sole nitrogen and carbon source. The cell-free extract catalyzes the hydrolysis of the amide group of the compounds and the hydrolase activity was influenced remarkably by the nitrogen source in the medium. L-Theanine and D-theanine were hydrolyzed to yield stoichiometrically L-glutamic acid and D-glutamic acid, respectively, and ethylamine, which were isolated from the reaction mixture and identified.

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The theanine hydrolase of Pseudomonas aeruginosa was purified approximately 200-fold. It was shown that the activities of L-theanine hydrolase, D-theanine hydrolase and the heat-stable L-glutamine hydrolase and D-glutamine hydrolase are ascribed to a single enzyme, which may be regarded as a γ-glutamyltransferase from the point of view of the substrate specificity and the properties. This theanine hydrolase catalyzed the transfer of γ-glutamyl moiety of the substrates and glutathione to hydroxylamine. L-Glutamine and D-glutamine were hydrolyzed by the theanine hydrolase and also by the heat-labile enzyme of the same strain of Pseudomonas aeruginosa, whose properties resembled the common glutaminase.

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When sake yeast Kyokai No. 6 was cultured in a phosphate-rich medium, the phos-phorus content of the cells increased at first and then returned to the normal at a stationary phase. In a phosphate-poor medium, however, the phosphorus content decreased below the normal but did not go down below 0.06mmol/g, the basal content.
The basal content of magnesium measured by the same way was 0.02mmol/g. When magnesium content of the cells was low, calcium was taken up into the cells.
The basal contents of the strains of brewer's yeasts were approximately the same.

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When sake yeast was cultured in a potassium-rich medium, the contents of potassium and sodium of the cells were almost constant during the course of cultural development. On the other hand, the potassium content decreased rapidly and the increase of the sodium content compensated the decrease of potassium at the earlier stage of the culture, then the sodium content decreased on the culture in a potassium-free medium.
The transfer of potassium through the cell membrane is reversible. Therefore, the potassium content of the inoculated cells cannot be the limiting factor for the growth.
These findings show that the growth-controlling mechanism of potassium is different from that of phosphorus or magnesium, since the conception of the basal content is not applicable to the case of potassium.

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Lipase from Candida cylindracea has been purified by ammonium sulfate precipitation, sodium deoxycholate treatment, ethanol-ether precipitation and chromatography on SE-Sephadex and Sephadex G-100 columns. The purification of the enzyme was 33.4-fold with a yeild of 18.0% on the basis of activity per weight of protein. The purified enzyme was homogeneous on ultracentrifugation and electrophoresis. Optimum pH for the hydrolysis of olive oil was 7.2 by the assay method using a polyvinylalcohol-emulsified system and 5.2 by the assay method using a shaken system without a macromolecular emulsifier. Optimum temperature was 45°C. The enzyme was stable up to 15°C and in the range of pH from 2.0 to 8.5. Sodium taurocholate showed either an activating or an inhibiting effect at pH 7.0, depending on the sodium taurocholate concentration and on the assay system.

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The unsteady-state gas analysis method was applied satisfactorily to the studies on the effects of oxygen transfer in glutamic acid fermentation. The following points were clarified:
1) When the sulfite oxidation method was adopted as a measure of aeration effec-tiveness, sulfite r_ab, the rate of oxygen transfer into sulfite solution, could be applied most widely.
2) As long as cultures were performed sup-plying air as the oxygen source, the results of the fermentation were well correlated with the value of sulfite r_ab, though the behaviours of sulfite solution to oxygen were not the same as that of fermentation broths.
3) Under the condition of high oxygen supply, sulfite r_ab lost its ability as a measure of aeration.
4) In all cases, biological r_ab, the rate of oxygen transfer actually occurring in the fermentation broths, could be an useful measure of aeration effectiveness.
5) It was difficult to employ PL, the level of dissolved oxygen, as a criterion of aeration in glutamic acid fermentation.
6) The best measure of aeration effective-ness, therefore, was concluded to be biological Tab, the next being sulfite r_ab.
7) For controlling the rate of oxygen supply in shaken cultures, the method of chang-ing the partial pressure of gas-phase oxygen in flasks by selecting suitable types of plugs or by purging flasks with gas of different oxygen concentration was preferable.
8) The optimum aeration condition for glutamic acid fermentation was 7×10^-7<biological r_ab, or 10×10^-7< sulfite r_ab<15×10^-7 (mol/ml.min).
9) Extremely high or low oxygen supply resulted in the low productivity of glutamic acid, though each condition was different in several points.
10) In the condition of slightly restricted oxygen supply, fermentation proceeded at the same rate as in the optimum condition and the yield of glutamic acid based on the amount of sugar consumed was lowered.

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Amides, IVa and IVb, which were derived from Grayanotoxin-II reacted very easily under a mild acidic condition to give a product, the structure of which has been established to be Va.

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5-Methylmercaptouracil was prepared by the reaction of uracil with dimethyl sulfoxide and monochloromethyl ether. At the same time the formation of methylal, methyl sulfide, methyl disulfide, methyl methanethiolsulfonate, methyl chloride and paraformaldehyde were observed. Acetyl chloride was successfully used instead of monochloromethyl ether. Uracil reacted with dimethyl sulfoxide and phenacyl bromides, resulting in the formation of 5-bromouracil. The mechanism of these reactions were discussed.

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Several guanineless mutants derived from Bacillus subtilis IAM 1145 were found to accumulate xanthosine in the culture broth. Further mutation of the guanineless mutants to adenine dependence led to remarkable increase in the accumulation of xanthosine. One of the guanine-adenine doubleless mutants, strain Gu-Ad-3-35, accumulated 8.9g of xanthosine per liter. Xanthosine was isolated in a crystalline form from the culture broth by a procedure involving charcoal treatment and ion-exchange chromatography.

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In order to clarify the mechanism of L-lysine accumulation by Micrococcus glutamicus No. 901, a homoserine-auxotrophic mutant, the effects of various amino acids on the two enzymic reactions on the biosynthetic pathway of lysine, the phosphorylation of aspartate and the condensation of aspartic β-semialdehyde (ASA) with pyruvate, were studied using the cell-free extracts of the organism.
The aspartokinase received a multivalent inhibition by threonine plus lysine. Lysine exerted no feedback inhibition in its first step condensing reaction. From these results, the mechanism of the accumulation of lysine by the organism was discussed.

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4-O-Methylgallic acid has been isolated from the wood of Poupartia axillaris.
This finding may be significant, for there are no previous references on its occurrence in plants.

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