Screening experiments for dipeptidase and aminopolypeptidase from 40 strains of molds were conducted using Leu-Gly, Gly-Leu, Ala-Gly and Gly-Gly-Leu as substrates.
The strains of Aspergillus oryzae RO-0129 A-2, IAM-2600 and IAM-2616 showed strong activities of both dipeptidase and aminopolypeptidase.
Further, optimal condi tions for making culture as well as those for the extractions of the peptidases from the mycerial mats were investigated.

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Barley endosperms (expt. A) and their finders (expt. B) which were obtained by cutting off the endosperms into about eight pieces, were incubated with gibberellin. The conditions under which α-amylase was activated were studied.-Amylase activation was proved to show maximum at 30°C and pH 4.7 in the both cases. Activation by several salts was also found in the both cases, especially in expt. B. Sugar (sucrose) rather retarded this activation. In expt. B α-amylase activation was found to increase in accordance with increasing concentration of gibberellin. In expt. A maximum activation was observed at 1 ppm of gibberellin.

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In the previous paper, it was reported that the higher molecular weight luteose which consisted of β-1, 6-linked D-glucose units was made by Pen. aculeatuin var. apiculatum. The isolation of the microorganism which is able to produce β-D-1, 6-glucanase and some properties of this glucanase were described in this paper. The optimum reaction temperature for this enzyme was at about 40°C, and the optimum pH was at about 6.7. At the maximum degree of the hydrolysis, only D-glucose and gentiobiose were detected, and at this point, the hydrolysis degree of higher molecular weight luteose was about 55% as D-glucose. The formation of β-D-1, 6-glucanase was induced by the addition of higher molecular weight luteose. From the property of this enzyme, the authors proposed the name “lutease” for this enzyme.

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Endogenous respiration of Aspergillus sojae K.S. was studied in terms of biochemical analysis. It was found that the different kind of substrates was utilized for the endogenous respiratoin according to C:N ratio of the agar medium on which the mold was grown. In the mycelial mats grown on the medium of low C:N value, pool amino acids, protein, and nucleic acids were mainly utilized from the beginning while carbohydrate or lipid displayed a minor role. The corresponding amount of ammonia was formed. On the other hand, in the mycelial mats grown on the medium of rather high C:N value, carbohydrate or lipid was the major substrate of endogenous respiration in the early stages of incubation. The utilization of the nitrogenous materials and the accompanying formation of ammonia got to start only after the lapse of several hours of incubation.

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Oak-silkworms (Anthereae pernyi) were reared from hatching to the adult stage on a diet consisting of powder of dry leaves of oak trees (Quercus dentata T.), ‘Iinako’(powder of parched soy bean), sucrose, agar-agar, sodium dehydroacetate as an antiseptic, and water. Among 100 newly hatched oak-silkworms reared on the diet, 23 spun their cocoons. The weight of the cocoon fibres spun by one worm and the number of the eggs laid down by one moth were 0.34g and 203, respectively, on the average.

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The incorporation of ¹⁴C-tyrosine into S-RNA catalyzed by a partially purified tyrosine activating enzyme from baker's yeast was observed. The maximum incorporation was shown in the presence of 5μgmoles of ATP, 10μmoles of MgCl₂ and 10-100μmoles of KCl in the reaction mixture of total volume of 1ml, at pH 7.8 when 1.2 mg of S-RNA, 0.1μmole of ¹⁴C-tyrosine and 400μg of enzyme protein were used. Beyond the concentration of ATP, MgCl₂ and KCl described above, the tendency of inhibition was observed. The incorporation was strongly inhibited by pCMB and reactivated by cysteine. Manganese and calciumions were effective as substitutes for magnesium. S-RNA used was prepared from whole baker's yeast cell with phenol, but S-RNA obtained from the supernatant of the ground yeast had lost its incorporating activity.

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The distribution in microorganisms of extracellular enzymes which degrade RNA into 5'-mononucleotides was studied. The degradation products of RNA were determined by using 5'-nucleotidase and adenosine deaminase.
It was found that the enzymes were produced by various microorganisms belonging to Streptomyces, Bacillus, Fungi imperfecti such as Fusarium, Helminthosporium, etc., and Ascomycetes such as Neurospora, Glomerella, Aspergillus, etc.

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Degradation of ribonucleic acid (RNA) was investigated with extracellular microbial enzymes capable of hydrolyzing RNA into products other than 5'-mononucleotides. The degradation products were analyzed by using 5'-nucleotidase and non-specific prostatic phopshomonoesterase. It was found that most microorganisms investigated, including Rhodotorula glutinis, Spolobolomyces pararoseus, Helicostylum piriforme, Poria vaporaria, Gibberella fujikuroi, Penicillium citrinum, Aspergillus flavus, and Rhizopus chinensis, produced enzymes which degrade RNA into 2'-(3')-mononucleotides. However, such microorganisms as Candida clausenii, Bacillus cereus, Absidia butleri, Mucor genevensis, Polystictus hirsutus, Polystictus versicolor, and Phycomyces blakeslecanus degraded RNA into oligonucleotides.
It is not clear whether the oligonucleotides formed from RNA by these microbial enzymes are terminated with 5'-phosphomonoester end group or with 3'-phosphomonoester end group.

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From the eggplant fruits, chlorogenic acid, neochlorogenic acid and caffeic acid have been isolated and identified. Enzymic experiments show that their O-dihydroxyphenolic compounds can be the browning substrates in the fruit flesh, on the other hand chlorogenic acid accelerates the decoloration of nasunin (delphinidin-glycoside) and enables to decolorize pelargonidin-3-glucoside by the anthocyanase.

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It has been found that exocellular α-amylase could be fixed to mycelia of Aspergillus oryzae at an acidic pH region and fixed α-amylase was released reversely at an alkaline pH region. The fixation has more remarkably been observed in mycelia obtained from a phosphate deficient medium where endocellular accumulation of α-amylase occurs more easily than in an ordinary mycelia which secrete a large amount of α-amylase into medium. Bound form of α-amylase was more resistant to low pH and less active than the free form. The results appear to support the previous suggestion that a large quantity of endocellular α-amylase might be located on mycelial surface of the mold.

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The β-crystal formation of L-glutamic acid in the seeded solution was investigated; and it was found that the growth rate of the seed crystals in a-axis direction was nearly as large as that of the α-crystal, but the growth rate in b- and c-axes was little recognized. The activation energy of the crystallization process of the β-crystal in a-axis direction was calculated from the growth rate constants determined at various temperatures, and 6-7kcal/mol was obtained. On the assumption that the crystallization of β-crystal growth was controlled by the diffusional operation, the thickness of the laminar film was calculated from the growth rate constant and the estimated value of the diffusional constant. The calculated value of the thickness was much greater than the value reported by Nernst; therefore, the crystallization process should be controlled by the surface reaction. The co-existence of a small quantity of amino acids caused a great reduction in the growth rate of the β-crystal.

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The methylations of heparin, heparitinsulfate, and three oligosaccharides (hexa, tetra and trisaccharides) from hyaluronic acid were carried out. Theoretical amounts of methoxyl group were obtained from the oligosaccharides and the desulfated product of carboxylreduced heparitinsulfate, but not from heparin and heparitinsulfate. The acid hydrolysis of the methylated trisaccharide confirms that the structure is β-D-glucopyranosyl uronic acid-(1→3)-2-acetamido-2-deoxy-β-D-glucopyranosyl-(1→4)-D-glucopyranosyl uronic acid.

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