From a screening of a few Ustilaginales fungi for free lysine accumulation, Sphacelotheca sorghi ITCC No.591 was found to accumulate 50μg/ml of free lysine in the culture medium. However, it was later seen that the free lysine content of the culture broths could not be increased much unless cell lysis took place.
Experiments were also carried out to increase the free lysine content of the culture broths of U. maydis PRL No.1092. It was found that U. maydis maintained on sterilised corn, yields up to 400μg of free-L-lysine/ml in its culture medium in five days.

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Chemical investigations were made on a new unsaturated crystalline diuronide isolated from alginase hydrolysate of alginic acid. This uronide has [α] ²²_D-8°(in water), E^232mμ_1%=143 and m.p. 135.5-136.5°C (decomp.). The presence of an α, β-unsaturated carboxylic acid formulation is supported by the following evidences:(a) an ultraviolet absorption band at 232mμ, (b) infrared absorption bands at 1648cm^-1 due to double bond and at 1720cm^-1 due to conjugated carboxylic group, (c) the consumption of about 1 mole of bromine per mole of the compound, (d) the production of oxalic acid on oxidation with ozone, (e) the formation of a substance that shows absorption maximum at 550mμ caused by the addition of thiobarbituric test. After hydrolysis, crystalline mannuronic lactone was obtained from the unsaturated diuronide. Occurrence of mannuronic moiety in the reducing unit was observed by paper chromatography of the hydrolysate of borohydride-reduced unsaturated compound. From these results it can be seen that the possible structure of this unsaturated diuronideis4-O-(β-D-Δ4, 5-mannoseenpyranosyluronic acid)-D-mannuronic acid.

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The present investigation is concerned with the effects of biotin and glucose on glutamic acid fermenation by Microbacterium ammoniaphilum. Both optimal amounts of biotin necessary for maximum growth and maximum accumulation of glutamic acid were determined under the conditoin of various concentration of glucose. As the glucose concentratin was increased, the amounts of biotin required for maximum growth also increased proportionally to thé glucose concentrations. The optimal amounts of biotin for maximum accumulation of glutamic acid were smaller than those for maximum growth of cells at any glucose concentration. It is suggested that the process of glutamic acid accumulation is inevitably associated with the process of cell multiplication by both experiments of successive culture of cells grown under the dose of biotin sufficient and deficient for maximum growth.

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Further confirmation of 2-methyl-γ-pyrone structure in rubrofusarin through a color reaction with alkaline dinitrobenzene and through preparations of the styryl compound and isoxazole derivative is presented. Evidences which favor the linear naphthopyrone structure for rubrofusarin are also given.

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A fresh cake of Chlorella cells was extracted with hot methanol and ether. The extracted lipid was saponified. The unsaponifiable substance, 2.7% of the dried Chlorella cells, was extracted with petroleum ether to separate hydrocarbons and higher alcohols. The extract was fractionated by the vacuum distillation, and each fraction was further separated by the solubility difference of the urea adducts followed by column chromatography. Small amounts of n-hexadecane and n-hexacosene were isolated besides phytol which was the major component of the unsaponifiable substance. Another unsaturated hydrocarbons with straight and branched chain were also found. The residue of the petroleum ether extract was extracted with ether to separate sterols, the major component of which was found to be ergosterol.

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The carotenoid pigments prepared from methanol and ether extracts from Scenedesmus were separated into epiphasic, midphasic and hypophasic fractions by partition between petroleum ether and 90% methanol. Each fraction was subjected to column chromatography, using aluminium oxide, magnesium oxide, calcium hydroxide and calcium carbonate as adsorbent. The absorption maxima of the separated pigments in hexane and carbon disulfide were compared with those of the known pigments. Some of them were identified as those previously known, which are as follows:α-carotene, β-carotene, polycis-lycopene VI, astacin, lutein, lutein-5, 6-epoxide, antheraxanthin, taraxanthin, violaxanthin, astaxanthin and neoxanthin.

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Enzymatic activity for isomerizing D-glucose to D-fructose was demonstrated in the extracts from the D-xylose-grown cells of heterolactic acid bacteria; the enzyme was called the D-glucose isomerase. D-Xylose was found to be the only active source of carbon among the sugars tested for this enzyme production. Supplements of manganese and cobaltous ions to synthetic or malt extract media caused the remarkable acceleration on this enzyme production.

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D-Glucose and D-xylose isomerases were purified on a column chromatography of DEAESephadex. Optimum pH for both isomerases was found to be at pH 6.0 to 7.0, but Michaelis constants for two substrates were markedly different: 0.52 M for D-glucose, and 1.3×10^-2 M for D-xylose. Purified enzyme has not shown any activity for dehydrogenation of D-sorbitol or xylitol, and these sugar alcohols inhibited both isomerase activities competitively. So, it was supposed that the isomerization of D-glucose or D-xylose proceeded directly without participation of their sugar alcohols.
Both isomerase activities could not separate from each other, and their activities were inhibited in the presence of two substrates, so it would be probably assumed that the D-glucose isomerase was identical with the D-xylose isomerase.

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Cytological effects of glycine on Bacillus subtilis var. conyloliquefaciens were compared between the cells of the glycine-sensitive parent and resistant mutant. Glycine induced disruption of the protoplasts which had been prepared by treating the glycine-sensitive cells with lysozyme. This effect of glycine was almost completely prevented by preincubating the protoplasts with spermine. The protoplasts prepared from the resistant cells were markedly stable in the presence of glycine. In this mutant, neither cell lysis nor cessation of the enzyme production by glycine occurred, contrary to the results obtained with the glycine-sensitive parent. Between both type of cells little difference could be observed in the metabolic activity for glycine, but free amino acid content was higher in the glycine-resistant cells than in the parent ones.

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The production of amylase and proteinase by the washed cell suspension of Bacillus subtilis var. amyloliquefaciens was inhibited by glycine, β-alanine and γ-aminobutyric acid in a decreasing order of effectiveness. The inhibition was competitively restored by the addition of amino acids such as alanine or glutamic acid. By the addition of alanine, the incorporation and distribution pattern of glycine-C¹⁴ into various cellular fractions were not affected, but the amino acid content of cells was increased. Tracer experiments suggested that 20 to 30 per cent of free glycine present in the cells was loosely associated with membrane lipid.

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Aspergillus quercinus (IFO 4363) was selected as the most suitable strain to produce 5'-mononucleotides from RNA among several species of Aspergillus which produced enzymes capable of degrading RNA into 5'-mononucleotides.
Aspergillus quercinus produced two kinds of RNA-depolymerases (designated as RNAdeploymerase I and II), phosphodiesterase, phosphomonoesterase and adenylic deaminase in the culture medium. The optimum pH of each enzyme was found to be about 4.5, 7.0, 5.0, 6.0 and 5.5, respectively. Maximal production of these enzymes in the culture medium occurred at 96, 96, 216, 168 and 264 hour culture, respectively. The culture filtrate of Aspergillus quercinus degraded RNA into 3'-mononucleotides at the pH lower than 6.0, into 5'-mononucleotides at the pH higher than 8.5 and into both mononucleotides at the pH range between 6.0 and 8.5. 5'-Inosinic acid was prepared from RNA by using the extra- and intracellular enzymes of Aspergillus quercinus.

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The production of acid protease, as well as that of other enzymes, involves many variable factors, such as rate of aeration and agitation, temperature control during the operation, components of the media and type of antiform agents. The proper control of such factors can be achieved through effective utilization of a well-equipped pilot plant, designed specifically for the acid protease research and development. The fermentation unit described ranges in capacity from 500 ml shake-flask to 20-liter jar fermentor. Detailed studies on the various conditions for the production of acid protease by Aspergillus usamii, Aspergillus saitoi and other related species are described. It was found that high rates of agitation and aeration were required to obtain acid protease in maximum yield.

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In order to determine the influence of different conditions on the manufacturing process of acid protease by the Kuro-Koji mold group, the effect of pH on the various procedures was studied systematically.

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