The effect of γ-irradiation on the flavor of Onions (Senshu Yellow) associated with sprout-inhibition has been investigated. The relative amounts of propionaldehyde, n-propyl mercaptan and di-n-propyl disulfide in onions stored for 0, 5, 10, 20 and 30 days, respectively, after irradiation were estimated by measurement of peak areas of gas chromatograms. It was observed that the Iachrymatory character and the pungent flavor had been decreased by γ-irradiation (remarkably at 70 and 700 Krads). In this connection, the amounts of propionaldehyde and di-n-propyl disulfide were decreased with increasing radiation dose and storage period at room temperature (20 to 25°C) and at low temperature (4°C). Moreover, it was observed that the sweetness had been decreased by γ-irradiation, but the amount of n-propyl mercaptan was increased with radiation dose and storage period. Therefore it seems that there is no correlation between the sweetness of onion and the amount of n-propyl mercaptan.

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The fractionation of the water extractable mucilage from the ripe fertile frond of Undaria pinnatifzda f. distans Miyabe et Okamura was studied. By an acid treatment, CPC-complex method, and DEAF-cellulose column chromatography this mucilage was separated into eleven fractions, of which the main polysaccharides were two fucogalactan sulfates (CPC-C-NaOH and CPC-N-NaOH) and an alginic acid. Judging by the ultracentrifugal analysis the formers are respectively composed of one component. They are probably identical, if their molecular sizes may differ slightly each other. Contents of the constituents in them are as follows: CPC-C-NaOH (main fucogalactan sulfate): fucose, 16; galactose, 21.5; sulfuric acid, 27.5%. CPC-N-NaOH (minor fucogalactan sulfate): fucose, 20.0; galactose, 30.7; sulfuric acid, 31.2%. Therefore, there exists in those compounds one sulfate residue per each sugar.
The ratio of D-mannuronic acid to L-guluronic acid in the alginic acid was found 0.87; and this value changed, by the KCI fractionation of it, to 1.64 for the KCl-insoluble frac-tion and to 0.76 for the KCI-soluble fraction.

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When 8% casein basal diet was supplemented with 0.3% DL-methionine or 0.3% DL-methionine plus 0.36% DL- or 0.18% L-threonine, the changes in urinary excretions of urea and allantoin were examined in weanling male rats of Wistar strain with the observations on the body weight gain and % nitrogen retention. Carbohydrate sources used were sucrose or an equimolar mixture of glucose and fructose (G-F) in place of pregelatinized starch used in the previous experiments.
In contrast to the previous results, differences in nitrogen utilization, expressed in term of growth rate or % nitrogen retention, became significant by the addition of 0.3% meth-ionine to the basal diet and it was further increased by the simultaneous supplementation with 0.36% DL- or 0.18% L-threonine.
Urea excretion was the main variable in total urinary nitrogen output to cause the significant difference in % nitrogen retention between the groups. As postulated in the previous paper, thus, the use of sucrose or G-F mixture considerably exaggerated these group-differences in such various indices as body weight gain and % nitrogen retention, and this trend became more distinct in the urea and allantoin excretions.
Liver arginase activity inversely changed with urea excretion, but proportionately to the qualitative improvement of dietary protein by the addition of methionine or methionine plus threonine. Changes in liver glutamic dehydrogenase activity were also parallel with the improvement of dietary protein quality.

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Quantitative studies on the dissolution and dissociation of carbon dioxide in a cultured system were made. The inosine fermentation and the glutamic acid fermentation were employed for this study. According to the results obtained in this experiment, the quantity of dissociated carbonic acid in cultured liquid was given by Henderson-Hasselbalch's equation with experimental pK'. The method for the direct determination of bicarbonate ion concentration was also investigated. The WVarburg direct method gave a satisfactory result for this purpose.

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By using the modified Severinghaus CO₂ electrode, the relationship between partial pressure of carbon dioxide in effluent gas and that in culturing system was investigated. Partial pressure of carbon dioxide in gas phase was almost equivalent to the average value of dissolved carbon dioxide tension in liquid phase for a given short time of the fermentation. The term of r_e was introduced in order to study the dynamic characteristics of carbon dioxide evolution in submerged fermentors. The dynamic characteristics of respiration in submerged fermentation was also studied by using biological r_ab and r_e.

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The first isolation of naturally occurring salicylamine and its Schiff base, 2-hydroxy-N-(2'-hvdroxybenzylidene)-benzylamine and the co-existence of free 4-hydroxybenzylamine in the achenes of Fagopyrum esculentum Moench which are commonly used as human food in Japan, have been described.
The structural confirmation of these compounds as carried out on the basis of the elementary analyses and spectroscopic properties and, eventually, by comparison with authentic specimens, if necessary.

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A computerized learning machine has been worked out to predict the presence or absence of a certain feature in microorganisms. Descriptions are made on (a) the principle of the decision making whether a feature is present or not, (b) the algorism adopted in the computer program used, and (c) the proposal of three measures by which predicted results are evaluated.

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A computerized learning machine was applied to pseudomonads to predict the presence or absence of the following four features; the production of phenazine compounds, the utilizations of D-sorbitol, of n-hexadecane, and of histamine. On all of the three measures of evaluation proposed in Part I, the results obtained for all of the above four features were far better than those expected in the case of random guess.

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Many strains of Bacillus subtilis were found to secrete several hemicellulolytic enzymes such as arabinoxylanase, galactomannanase, arabinogalactanase, etc. Chemical and enzy-matic properties of certain strains of the bacterium were comparatively investigated. An arabinogalactanase was purified and obtained in a crystalline state. Its molecular weight and isoelectric point were estimated to be 3.7 ×10⁴ and 8.39, respectively. The enzyme showed an optimal pH for reactions at 6.0, and was stable in a pH range of 5.0 to 9.5 at 30°C. It required no metallic ions for its activity and hydrolyzed soybean arabinogalactan, forming galactobiose as the main product. No liberation of arabinose was observed in the hydrolysate. Also, the enzyme did not attack coffee bean arabinogalactan. Some implications of the experimental results are discussed.

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In bacteriophage φX174 infection, the net synthesis of replicative form DNA ceased between 15 and 20min after infection. When 30μg of chloramphenicol/ml was added, net RF synthesis, however, continued beyond the normal time and level of turn-off. Ex-periments with φX174 mutants unable to synthesize single-stranded DNA showed that a protein synthesis was required for the cessation of net RF synthesis and the protein was synthesized between 10 and 15 min after infection.

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The induction of adenosine-producing mutants from an inosine-producing mutant pre-viously derived from a Bacillus strain was attempted, and it was found out that the xan-thine-requiring mutants lacking of adenase produce a large amount of adenosine.
The outline of the processes for the derivation of these mutants was described. Main product of these mutants was adenosine, and the culture broth contained a little amount of adenine as a by-product.
The culture conditions optimal for the production of adenosine were investigated, and the yield of adenosine in the culture broth was more than 16mg/ml.

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The Acid-stable α-amylase and the acid-unstable α-amylase from Aspergillus niger contained one mole of sulfhydryl group per one mole of enzyme, which probably existed correlating with calcium atom that was essential for the amylase activity.
Iodine reacted at acidic pH specifically with the sulfhydryl group of both enzymes and oxidized it to considerably high degree, since about 4 eq of iodine per mole of sulfhydryl group of both enzymes were consumed. The modification of the sulfhydryl group of the acid-stable α-amylase did not affect the amylase acitvity, while, that of the acid-unstable α-amylase reduced it to 70 per cents intact enzyme. It was difficult to carry out carboxymethylation of the sulfhydryl group of the acid-stable a-amylase under mild conditions maintaining its activity, but that of the acid-unstable α-amylase was easily achieved.
These facts suggested that some differences existed in the neighborhood of the sulfhydryl group of both enzymes, and that the sulfhydryl group of them was not the active site.

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A piscicidal constituent (1), C₂₀H₂₈O₃, [α]^20°_D-252° (chloroform), which was named maingayic acid, was isolated from the leaf of Callicarpa maingayi. On the basis of the chemical spectral studies, the pKsics evaluation and the octant rule on the ORD curves, we have and deduced that maingayic acid is a furanoid diterpene acid possessing a rearranged labdane skeleton shown as l'a.

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The relative stereochemistry of eervicarcin, an antitumor antibiotic, was determined as shown in 1, which represents the absolute stereochemistry also.

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Cooked pork fat was irradiated with γ-rays and volatile carbonyl compounds were spectrophotometrically examined after their conversion to 2, 4-dinitrophenylhydrazones. The main change was preferential loss of conjugated carbonyls, e.g., deca 2, 4-dienal. Under the deaerated condition, non-conjugated carbonyls did not change on irradiation. The loss was insensitive to the presence of oxygen, some electron and cation scavengers, and some excitation quenchers, but was somewhat prevented by the addition of laurylmercaptan or triphenylmethane. Some conjugated aldehydes added to the fat decreased on γ-irradiation. Various solvents were tested instead of the fat and conjugated aldehyde decreased more slowly in unsaturated solvents than in saturated ones. G(-conjugated aldehydes) value was estimated by using crotonaldehyde and the value of 0.8 was obtained.

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The effect of amino acid supplementation to a rice diet on the niacin requirement of rats was studied in relation to the phenomenon of niacin or tryptophan deficiency caused by the addition of threonine or gelatin to a low casein diet. Supplementation of a mix-ture of all limiting amino acids other than tryptophan to a 90% rice diet stimulated the growth of rats only temporarily without additional supplementation of niacin. However, the supplementation of the same mixture of limiting amino acids to a diet containing an amino acid mixture simulating rice protein, clearly decreased the growth of rats after a temporary increase. The growth was then remarkably improved by the further addition of niacin or niacin plus tryptophan. This result supports the hypothesis that the addition of all limiting amino acids other than tryptophan, increases the use of tryptophan for protein synthesis and may lead to niacin deficiency.

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Hexahydrohippuric acid was detected from the urine of cattles together with hippuric and phenaceturic acids as one of the conjugated compounds with glycine. Furthermore, cyclohexanecarboxylic acid was also detected. These experimental results suggest the interesting synthetic processes in vivo or in rumen of the cattle, though both acids have not determined whether they are metabolites of cattle or synthesized by miccroorganisms in rumen.

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The optimum condition for the formation of CDP-choline was studied: (1) the reaction proceeded more effectively at 35°C than at 28 or 40°C. (2) the maximum formation of CDP-choline was obtained at pH 7.5, when pH levels were kept constant throughout the reac-tion. (3) twenty μmoles per ml of 5'-CMP was the optimum concentration for the formation of CDP-choline. When higher concentration of 5'-CMP was employed, the substrate was decomposed to uridine, uracil, etc., and the yield of CDP-choline decreased. By the appli-cation of feeding method, 5'-CMP was utilized to the effective formation of CDP-choline without further formation of side-products.

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Allethrin-(E)-ol (IV), allethrin-(E)-al (V) and allethrin-(E)-acid (VI), the metabolites of allethrin (III) in the insect body, were synthesized. Their low toxicities to houseflies seem to support the hypothesis that they are products of the detoxication process of allethrin.

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From leaves of Chrysanthemum morifolium two stimulants for root initiation in mung bean cuttings have been isolated and identified as chrysartemins A and B (I and II). These substances showed synergistic activity on rooting with indoleacetic acid and were proved to be constituents of the “cofactor 4” designated by Hess.

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Some chemical properties of the rice bran lipase were studied. The enzyme protein contained 14.98% nitrogen and consisted of 312 amino acid residues. It also contained a certain amount of lipid. The amino-terminal amino acids of the enzyme protein were shown to be glutamic acid and the carboxyl-terminal amino acids to be glycine and serine. The treatment of the enzyme protein with 8_M urea containing 1×10^-3_M EDTA (ethylenediaminetetraacetic acid) seemed to cause dissociation of the subunits of the enzyme protein. From this observation and the results of the terminal amino acids analysis, it was presumed that the enzyme protein was composed of at least two types of subunits.

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