Fatty acid composition of lipids from polished rice was studied by gas chromatography on the separated fractions, fat-by-hydrolysis, neutral fat, free fatty acid and phospholipid. After six months storage, fatty acids were released from neutral fat in the same proportion as they were combined in the neutral fat.

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There are many reports on the deterioration during storage of rice flavor, but no work has yet been done to relate the change during storage in rheological properties with the change in lipid composition. The present study revealed that the increase in amounts of free fatty acids during rice storage resulted in the increase in maximum viscosity of amylogram, i.e., deterioration in rheological property of cooked rice. The mechanism is explained by the formation of helical structure of starch molecule with fatty acid.

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(1) When the barley endosperm flinders were incubated with gibberellic acid under the sterilized condition, α-amylase was produced. This production was inhibited by the anaerobic condition or by addition of potassium cyanide or 2, 4-dinitrophenol, either at zero hour or after 48 hours incubation, i.e. at the period when gibberellin was considered to be fully absorbed into the endosperm tissue.
(2) This α-amylase production was also inhibited by adding to the flinders chloramphenicol either at zero hour or after 48 hours incubation.
(3) This α-amylase production was inhibited remarkably when amino acid analogues (ethionine or norleucine) were added to the medium at zero hour but no inhibition was found when they were added after 48 hours incubation. And the inhibition by addition of ethionine at zero hour was recovered to the considerable degree when methionine was added at the same time, but the inhibition by norleucine was recovered only about 40% when norleucine and leucine were added at the concentration ratio of one to two at zero hour.
(4) 8-Azaguanine and 5-bromouracil did not inhibit noticeably the production of α-amylase.
(5) From the results described above, the authors considered that, in the α-amylase Production of barley endosperm flinders with gibberellic acid, a kind of biosynthesis plays a great part.

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1. It was confirmed that washed yeast cells produced isobutanol from α-acetolactic acid. At the same time α-ketoisovaleric acid was formed.
2. These results strengthen the reliability of the presumptive scheme of the formation of isobutanol from alanine proposed by us.
3. Effect of aeration, vitamins and yeast strains on the formation of isobutanol from α-acetolactic acid was examined.

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The changes of free and conjugated vitamin B₁₂ content and pentose and deoxyribonucleic acids have been determined from the zero day through the 18th day of development.
1) Taken as a whole, DNA and RNA contents in embryo increase with the growth of embryo, but especially the synthesis of both nucleic acids occurs most markedly from the 12th day through the 14th day during the most rapid growth of the embryo. When the change of nucleic acid expressed as mg per g of wet weight, RNA content after markedly decreases from the 3rd day to the 7th day increases distinctly until the 13th day of incubation before falling off. DNA also shows the same change, i.e., since from the 3rd through 7th day decrease is slight, it begins to increase from the 8th clay and attain maximum content at the 13th day.
2) On the other hand, the nucleic acid content in the egg content shows a gradual increase until the 13th_??_14th day and then falls gradually.
3) The enzyme-digesting method is most efficient in order to extract total vitamin B₁₂ in the egg and embryo. For the determination of the free state of vitamin B₁₂, the method to remove protein in homogenate with ethanol is proper.
4) The considerable amounts of free vitamin B₁₂ is contained in the chick embryo, and this state of vitamin B₁₂ increases rapidly at later stages of the incubation. The change of the ratio for free vitamin B₁₂ to total vitamin B₁₂ in the embryo is as follows: 75% on the 3rd day, 28% on the 4th, about 10% on the 5_??_6th, 12% on the 7_??_8th days, while on the 13th day only 5%, on the 18th day about 25%. Conjugated vitamin B₁₂ shows a marked increase at first stages of incubation, and then a gradual increase until the 14th day incubation before falling off.
5) The free vitamin B₁₂ in egg content is hardly found at the first stage of incubation. It is found that the free vitamin B₁₂ increases gradually in process of incubation day, especially the production is highest at the stage of incubation, i.e., though the ratio of free state to total vitamin B₁₂ on the date from 5th to 10th day of incubation is only about 1%, on the 15th and 18th days, respectively, 6% and 10%.
6) When the free vitamin B₁₂ content mμg per wet weight g in embryo is compared to that on the egg content, free vitamin B₁₂ content in the embryo attains to 200 times to the egg content on the 4th day, 45 times on the 7th day, 15 times on the 11th day and 7 times on the 15th day of incubation. In the embryo conjugated vitamin B₁₂ content is only about 2_??_3 times of that in the egg content from the 5th day through the 18th day of incubation (see Fig. 16).
7) It seems that vitamin B₁₂ content in the whole egg is constant during the incubation.
8) As the growth factors of L. leichmannii, the embryo contains hydroxycobalamin and some anti-alkali factors in addition to cyanocobalamin and in the egg content, cyanocobalamin and hydroxycobalamin are found.

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Seven strains of microorganisms selected by the previous screening tests were further compared on their ability to produce extracellular enzyme systems capable of degrading RNA into 5'-ribonucleotides. As a result, two strains of Streptomyces were finally concluded to be most preferable. When these two were applied, the rate of 5'-nucleotide production reached up to 70%.
Bacillus subtilis was outstanding in its activity to degrade RNA, but its PDase activity producing 5'-nucleotides from RNA was found to be lower than those of Streptomyces strains. A pathway involving 3'- and 5'-nucleotides as intermediates was proposed for the degradation of RNA by the Bacillus enzyme system. The activity of RNA-degrading enzyme system of Bacillus subtilis contained in the supernatant of culture fluid was found to be lost at 70°C but remained to certain extent at 100°C, a possible mechanism for the phenomenon being discussed. Usability of the Bacillus enzyme system in the practical production of 5'-nucleotides under the condition of high RNA concentration was discussed.

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When weanling male rats were fed amino acid diets which were gradedly varied tryptophan level only (0.18, 0.09 and 0.06%), allantoin and urea excretions were determined, and (allantoin/urea)×protein intake values were calculated. (Allantoin/urea)×protein intake values almost linearly increased with the increment of tryptophan level of the amino acid mixture. From these data, it was assumed that one of the main factors affecting these ratios is in amino acid balance in diet. It was also found that the equivalent weight gains observed between 0.18 and 0.09% Try. groups were mainly due to body fat accumulation of the latter.

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Synthesis of theanine from glutamic acid and ethylamine in the presence of ATP was observed by the use of a homogenate of tea seedlings. The mechanism of theanine biosynthesis is discussed.

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A convenient method for the measurement of radioactive theanine formation was devised. Theanine synthesis by a pea seed acetone powder extract from glutamic acid and ethylamine in the presence of ATP was proved. Some properties of this reaction were examined, and the mechanism is discussed.

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Theanine synthesis by a pigeon liver acetone powder extract is reported. Some properties of this reaction were examined.

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A saccharifying pectate trans-eliminase was found in the cells of Erwinia aroideae. This enzyme differs from known pectate trans-eliminate in the next two points. It degrades pectic acid liberating 4, 5-unsaturated digalacturonic acid from the chain end of the molecule. It does not require calcium ion.
Some properties of 4, 5-unsaturated digalacturonic acid, the main product of the saccharifying pectate trans-elimination, were also described in this paper.

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