Data are presented showing the relationship of flavanolic constituents to tea leaves to the position in plucked shoots and to the stages of growth at various seasons. The results indicate that with the development of tea leaves, there is an increase of (-)-epigallocatechin and decrease of (-)-epigallocatechin gallate and (-)-epicatechin gallate. This suggested that past common data on the variation of tannin content is not always sufficient for such_??_subject.

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A bacterial strain, HN-500, having an activity of D-glucose isomerization was newly isolated from soil, and was identified to be similar to Escherichia intermedia (Werkman and Gillen) Vaughn and Levine. The strain, grown on wide varieties of carbon sources, shows definitely D-glucose isomerizing activity in the presence of arsenate. D-Fructose formed in reaction mixture was identified by paper chromatography and was isolated in crystalline form from calcium-fructose complex. In order to increase the production of D-glucose isomerase, D-glucose and ammonium nitrogen were effective carbon and nitrogen sources, respectively, but none of the metallic ions tested were effective, furthermore manganese, ferrous and ferric ions present more than 10^-5M in growth medium fully repressed the enzyme formation. The cells grown on carbon sources other than D-xylose showed no activity of D-xylose isomerase.

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Optimum conditions for reaction of D-glucose isomerase from Escherichia intermedia, strain HN-500, grown on D-glucose were investigated together with some enzymatic properties. The optimum pH for the reaction was 7.0 and the maximum enzyme activities of varied incubation times of 10, 24 and 48 hours were found at 42.5°, 40.0° and 37.5°C, respectively. Practically, any of the metallic ions given in reaction system did not enhance the enzyme activity, and sulfhydryl reagents inhibited the reaction, but metal chelating agents affects little if any. Arsenate was proved to be indispensable for the isomerase activity itself, so that the reaction velocity varied with the concentration of both arsenate and glucose in reaction system. The isomerizing reaction proceeded to equilibrium from either sugar, i. e., D-glucose and D-fructose, and the equilibrated mixture contained 50per cents both of D-glucose and D-fructose.

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1. The activity of muramidase on glycol chitin was assayed by measuring the reducing power arising from the hydrolysis of the substrate.
2. The increment in the reducing power became small with a lapse of time and the curve representing the relation between the reducing power and the reaction time reaches a constant value within 4 hours. This value depends on the conditions used for the hydrolysis reaction.
3. The phenomenon that the reducing power reached a constant value within 4 hours depending on the conditions used, such as temperature and the ratio of enzyme to substrate, may be partly caused by product inhibition.
4. The reducing power decreased appreciably on allowing the reaction mixture to stand for times much longer than 8 hours. This decrease in the reducing power observed after a prolonged incubation means that there is some kind of a reverse hydrolysis reaction or a transglucosaminide reaction.
5. The complexity of the muramidase action on the substrate is attributable to the combination of the product inhibition and the reverse hydrolysis reaction.
6. For the application of reducing power method to the assay for the muramidase action, the well-controlled conditions should be used.

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The egg white was treated under various whipping conditions, and its foaminess measured. At the same time, the amounts of the coagulated proteins formed from each egg white and their constituent hexose were measured. From these results, discussions were made about the relation between the foaminess of the egg white and the amount of the coagulated proteins under various whipping conditions.

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When ovomucin (B) was added to the egg white, its foam stability was greatly increased although its foaming power was decreased a little. On the other hand, other proteins of the egg white had little effect on the foam stability of the egg white. The solution of ovomucin (B) was highly viscous and other highly viscous solutions gave almost the same effect on the foaminess of the egg white as that of ovomucin (B). From these results, discussions were made about the role of ovomucin (B) in the foaminess of the egg white.

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Endo-polygalacturonase I from Coniothyrium diplodiella has been purified. The purified enzyme was homogeneous on ultracentrifugation and free-boundary electrophoresis. The isoelectric point and the sedimentation coefficient were found to be approximately 7.6 and 2.68S, respectively. The enzyme was completely inactivated by heating at 50°C for 10 min. and at 40°C was most stable in the pH range of 4.0_??_4.5. The enzyme rapidly decreased the viscosity of a solution of pectic acid and released reducing groups by a random attack of glycosidic linkages. Pectin underwent only a slight degradation, which was sufficient to cause a decrease in viscosity but gave little release of reducing groups. The enzyme attacked all of the galacturonides except digalacturonic acid. The extent of hydrolysis of pectin (esterification degree, 64%) and pectic acid was 11.6 and 73.8% respectively.

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Endo-polygalacturonase II from Coniothyrium diplodiella has been purified. The purified enzyme was homogeneous on ultracentrifugation and free-boundary electrophoresis. Its sedimentation coefficient was approximately 3.3S. The enzyme was stable at 45°C and in the pH range of 4.0_??_6.0, but completely inactivated by heating at 60°C for 10 minutes. The enzyme carried out a random hydrolysis of pectic acid resulting in a mixture of digalacturonic and galacturonic acids as the end products of hydrolysis. The extent of hydrolysis of pectic acid was 68.8 per cent. The ratio of VRu (viscosity-reducing activity) to PGu (reducing group-releasing activity) was 1.32.

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A method for the purification of endopolygalacturonase III from Coniothyrium diplodiella has been developed. By fractionation with ammonium sulfate and chromatographies on a cation exchanger, Duolite CS-101, and DEAE-cellulose, endopolygalacturonase III was concentrated 25-fold with a yield of 4.5% on the basis of polygalacturonase activity per weight ototal nitrogen.
The purified enzyme was homogeneous on ultracentrifugation and free-boundary electrophoresis. Its sedimentation coefficient was approximately 3.6S. The enzyme was most active in the pH range of 4.0_??_4.5. The enzyme was stable at 40*°C and in the pH range of 5.0_??_6.5, but completely inactivated by heating at 60°C for 10 minutes. The enzyme carried out a random hydrolysis of pectic acid to a mixture of mono-, di- and tri-galacturonic acids as the end products of hydrolysis. The extent of hydrolysis of pectic acid was approximately 54.0%. The ratio of VRu (viscosity-reducing activity) to PGu (saccharifying activity) was 3.00.

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During the study on the oxidative sugar metabolism of yeasts, it was found that six strains of Candida robusta, isolated from fruits, produced large amounts of yellow pigment in shaking culture and this pigment was identified as riboflavin. Riboflavin production by C. robusta has never been reported.
Some notable characteristics of C. robusta in riboflavin production were found. As nitrogen sources, ammonium salts and urea were favorable, but nitrate and organic nitrogen sources such as glycine, asparagine and peptone were not utilized for riboflavin production. Riboflavin was not produced in still culture; a highly aerobic condition, as may be obtained by shaking culture, was essential. The addition of excess CaCO₃ was also necessary. Acetic acid, added as the Ca salt in its production as a sole carbon source, was more effective than sugars and optimum concentration of this acid was 7%. Riboflavin were obtained in yields as high as 32 to 34mg % from the acetate medium after 8 days.

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All of six strains of Candida robusta isolated from fruits produced larger amounts of riboflavin in acetate medium than in sucrose medium. Strain No. 6 was selected as the best one for its production. Two type cultures of this species, however, did not produce any riboflavin in either medium. The riboflavin-producing ability may not necessarily be, therefore, a general property of C. robusta. Candida guilliermondii gave riboflavin in a small yield in sucrose medium, but did not produce it in acetate medium.
Ammonium salts and urea, as well as organic nitrogen sources such as amino acids, asparagine and peptone, which were unsuitable in sucrose medium, favored riboflavin production by C. robusta in acetate medium. Apparently no flavinogenic factor was necessary for this yeast.

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