A new method determining the activity of tannin acyl hydrolase (tannase) was made. This method was based on the change in optical density of substrate tannic acid at 310 mμ. In this method, the error of measurement was about 1_??_3%, and many samples could be tested at one time because of its simplicity.
The procedure was as follows; To four parts of substrate (0.350 w/v% of tannic acid dissolved in 0.05M citrate buffer, pH 5.5), one part of the enzyme solution was added.
After t minutes reaction at 30°C, 0.1 part of the mixture was added to ten parts of 90% ethanol.
The optical density of the ethanol solution at 310mμ was measured. Tannase activity (unit/ml) was given by following equation.
u=114×E_t1-E_t2/t₂-t₁
Where E_t1 and E_t2 mean the optical density of the ethanol solution at 310mμ prepared after t₁ and t₂ minutes reaction, and one unit of the enzyme means the amount of the enzyme which is able to hydrolyze one p mole of the ester bond in tannic acid in one minute.
The substrate tannic acid used in this determining method was purified. It was composed of one mole of glucose and nine moles of gallic acid, and eight moles of which formed four moles of m-dieallic acid.

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A study was made of thermogravimetric analyses of microcrystalline cellulose, (Avicell), over a temperature range from 240°C to 300°C under air and nitrogen by means of a thermal balance. For comparative purpose, cellobiose and glucose were also used. The volatilization rate of cellulose was related to the amount of pyrolytic residue and accelerated owing to the oxidation in the presence of atmospheric oxygen. The apparent activation energies of pyrolysis were obtained from weight loss data.
Quantities of carbonyl and carboxyl groups in pyrocellulose increased linearly against degradation stages of cellulose irrespective of pyrolytic temperatures and times.

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Pyrimidine nucleoside phosphorylases obtained from Er. carotovora and Cor. sepedonicum were purified by means of ammonium sulfate fractionation and DEAE-cellulose column chromatography. Some properties of these enzyme were also studied. The enzyme from Cor. sepedonicum catalyzed the formation and the degradation of uridine only, although the enzyme from Er. carotovora catalyzed the formation of thymine riboside as well as uridine. Optimum pH of the enzyme from Cor. sepedonicum was 9.0 and that of Er. carotovora was 7.0.

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Purine nucleoside phosphorylases obtained from Er. carotovora and Cor. sepedonicum were partially purified and some properties of these enzymes were studied.
Purine nucleoside phosphorylases obtained from Er. carotovora and Cor. sepedonicum catalyzed the formation of inosine, guanosine, adenosine and xanthosine, though the reaction rate was different with each enzyme.

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Out of some 800 strains of microorganisms, a potent fungus for milk clotting enzyme was isolated from soil during the course of screening tests and was identified as one of strains of Mucor pusillus Lindt. Satisfactory results were obtained in cheese making experiments with this enzyme which could be produced effectively by solid culture on wheat bran at 30°C for about 70 hrs.
The balance between milk clotting activity and proteolytic activity of this enzyme resembled very much to that of rennet.

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Microbial rennet from Mucor pusillus F-27 was obtained with high productivity by solid culture followed by water extraction. The enzyme could be precipitated by salting out with ammonium sulfate and also by mixing with various water-miscible organic solvents such as ethanol, methanol or acetone.
This enzyme is one of acid proteases having its optimal pH for milk casein digestion around 3.5. The ratio of milk clotting activity to proteolytic activity of this enzyme resembled that of calf rennet than those of other proteases of fungal origin. This was more heat stable and more resistant against pH changes than animal rennet. Apparent activity of milk clotting was more affected by Ca ion concentration in milk than that of calf rennet.
The liberation of 12% TCA soluble nitrogen from casein fraction was a little less specific than that of calf rennet. The optimal temperature for milk clotting lay around 56°C.
Electrophbretic patterns of a-peak of casein treated with this enzyme showed the weak proteolysis which resembled that with rennet.

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Pectinesterase of Sclerotinia arachnidis was purified by 44 times. The clarification of apple juice with the purified pectinesterase and the formerly purified endo-polygalacturonase of Aspergillus saitoi was examined. The coexistence of pectinesterase and endo polygalacturonase was necessary for the complete clarification of apple juice. During the clarification reaction rapid decrease of viscosity and resultant coagulation of the suspended materials in apple juice were observed. The coagulated materials slowly precipitated leaving clear juice. It was suggested from the result of electrophoresis that the positive charge existed inside of the suspended materials. The decrease in viscosity was supposed to correlate to pectin's depolymerization which would result in revealing of positive charge inside. The probable mechanism of coagulation was attributed to the electrostatic neutralization between positive charge thus appeared and negative charge of still undegraded pectin.

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Acetylesterase (AcE) of Sclerotinia libertiana was purified approximately 1170-fold, and proved homogeneous by electrophoresis, ultracentrifugation and chromatography. The purified AcE hydrolyzed various acetyl esters in the following order; vinyl acetate, triacetin, n-butyl acetate, p-nitrophenylacetate, diacetin, ethylene glycol diacetate, monoacetin, ethyl acetate, acetylcholine, methyl acetate. It also had apparently a slight activity on tannic acid, benzoylcholine, methyl butyrate and acetic anhydride.
The mode of AcE reaction on these substrates could be divided into two types of group by Lineweaver-Burk plot, one forms the enzyme-substrate complex, ES, and the other, SES additionally combining substrate at a high substrate concentration.
From the inhibition experiment by organic acids, it was suggested that the neighbouring carboxyl groups of the di-, or tribasic acid such as citric, cis-aconitic, succinic, and maleic acid have a significance on inhibition of the AcE. Also, choline esterase inhibitor partially inhibited the activity on acetylcholine, and bivalent metal ion increased the activity on triacetin. Thus, the AcE was supposed to have a many adjacent sites of interaction with the substrate.

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Adenine-auxotrophic mutants were derived from Corynebacterium petrophilum SB 4082 by ultraviolet irradiation. The isolation of this auxotroph was carried out as follows; the adenine-auxotrophic mutants which had been derived by the UV irradiation were concentrated with penicillin. The auxotrophs were raised in concentration by recycling procedure and were separated by the ordinary method. The resultant adenine-auxotroph was cultured in the hydrocarbon medium. From its filtrate was obtained a fermentation product as crystals by means of ion-exchange resin and identified as inosine from absorption spectra and other properties.

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The effects of cultural conditions on inosine production were investigated by the adenine auxotroph of Corynebacterium petrophilum SB 4082. That, the amount of adenine in the medium was very important on the inosine formation, was cleared. The addition of 10mg of adenine and 0.5 g of yeast extract to 100ml of medium was the best for the inosine formation. Ammonium chloride or ammonium sulphate was effective as nitrogen sources. As the carbon sources, n-C₁₀ to n-C₁₆ were utilized for the growth, but the hydrocarbons from n-C₁₂ to n-C₁₆ were the most suitable for the inosine formation. The inosine fermentation began at 24 hrs. after inoculation. The accumulation of inosine attained to the highest level after five days, the amount of which was 1.6g per liter of the culture filtrate.

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The structure of F-4 β-glucan, a minor component of water soluble non-starchy polysaccharides from the endosperm of naked barley, was elucidated. Hydrolysate of the methylated F-4 β-glucan gave 2, 3, 6-tri-O-methyl-D-glucose and 2, 4, 6-tri-O-methyl-D-glucose as main components with small amounts of 2, 3, 4, 6-tetra-O-methyl-D-glucose and unidentified di-O-methyl-D-glucose. This result indicated that the main chain of F-4 β-glucan consisted of 1, 4- and 1, 3-linked β-D-glucopyranose residues with proportions of approximately 2:1 (β-1, 4 linkage to be predominant) with some branching.

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Unpasteurized skim milk was storaged in a frozen state at -7°C or -20°C for up to several months. There was no increase of non casein and non protein nitrogens, but a slight increase of free tyrosine and a slight decrease of alkaline phosphatase activity were detected when storage period was prolonged. Destabilization occurred solely in caseinate complex, but non micellar casein appeared to be stable.
The contents of calcium and inorganic phosphate in the caseinate complex separated by ultra centrifugation were increased appreciably after frozen storage. The viscosity characteristics of frozen storaged skim milk was also investigated.

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Caseinate complex was ultracentrifugally separated from skim milk before and after frozen storage, and then lyophilized. Skim milk itself was also lyophilized before and after frozen storage. Dispersibility was examined on the reconstituted suspension of the lyophilized samples.
The lyophilized sample from frozen storaged milk was much less dispersible than the lyophilized control sample prepared before frozen storage. However, when lyophilized samples were once resolved with reagents such as urea and potassium oxalate and then dialyzed against fresh milk, stable micelle resulted in both samples prepared before and after frozen storage.
Some reduction of dispersibility occurred during lyophilization and subsequent storage in a dried state in the caseinate complex prepared before frozen storage. This reduction was small when skim milk was lyophilized and stored.

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Phenylalanine ammonia-lyase, which catalyzes the conversion of L-phenylalanine to trans-cinnamic acid and ammonia, has been partially purified from the cells of Rhodotorula. Some of the properties of this phenylalanine ammoyia-lyase were investigated. The enzyme was stable in phosphate buffer of pH over the range of 6.0 to 7.0 On heating, the enzyme was stable up to 50°C, but above 60°C, it was destroyed. The enzyme activity was strongly inhibited by p-chloromercuribenzoate at 10^-5M and almost recovered by the addition of glutathione or mercaptoethanol at 10^-3M. The present enzyme preparation of Rhodotorula also catalyzed the deamination of L-tyrosine to trans-p-coumaric acid. trans-p-Coumaric acid was isolated from the reaction mixture and identified by its absorption spectra. The rates of deamination showed optima at pH 9.0 and 9.5 for L-phenylalanine and L-tyrosine, respectively.

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S-(-)-2-Isopropyl-5-oxohexanoic acid was isolated from the ether extract of Turkish tobacco leaves. Since 2-isopropyl-5-oxohexanoic acid obtained by ozonolysis of (+)-solanone was leavorotatory, tobacco-derived solanone has R-configuration and might be a precursor of the acid in tobacco leaves.

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Several bacteria capable of accumulating large amounts of unknown sugars in culture medium were isolated from natural sources.
These bacteria were identified taxonomically as genera of Brevibacterium and Corynebacterium, respectively.
The sugars accumulated were isolated by paperchromatography and they were identified as a mixture of D-ribulose and D-xylulose.
Time course of sugar production by one of several strains selected shows that the ketopentoses were accumulated progressively with incubation time and that their maximum yield was approximately 7 to 8mg per ml of the culture broth.

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A pellet diet consisting of 50% of alfalfa meal, 45% of wheat starch, and minerals in addition to manganese dioxide was fed to the rabbits fistulated in the duodenum and ileum for sampling of small intestinal digestive product arbitrarily. By means of redox dyes, pH, Eh and rH2 of digestive products were determined. Results showed that ileum digestive product was more reductive than duodenum one, and the latter has a greater buffering capacity than the former.

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The influence of nutritional alteration to the plasma amino acid patterns in cows was investigated. The ratio of the essential to nonessential amino acids (E/N) at 6 months after change of diet was higher in the group fed a high protein and low energy diet than the group fed a moderate protein and moderate energy diet (the control group). The total nonessential amino acid levels decreased in the former group. The decrease was due to lower values for glycine, alanine and glutamic acid.
On the other hand, the E/N radio was lower in groups fed low protein diets than in the control group and total essential amino acid levels were lower in the former group than in the control group. The decrease was due to lower values for valine, threonine and arginine. Conversely, the higher values in glycine, serine and proline than those in the control group were observed.

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