Naringinase, which was induced from Aspergillus niger, consisted β-D-glucosidase and α-L-rhamnosidase. The former was successfully inactivated by heating the crude enzyme solution at 60°C and pH 6.4_??_6.8, whereas the latter was very stable under such treat-ment. By using this enzyme solution flavonoid gycosides were partially hydrolyzed and prunin from naringin, isosakuranin from poncirin, hesperetin-7-β-D-glucoside from hesperidin and neohesperidin, isoquercitrin from rutin, cosmociin from rhoifolin were obtained respec-tively in good yields. Furthermore kaempherol-3-robinobioside, a new flavonol glycoside, and afzelin were obtained from robinin and kaempheritrin, respectively.

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The viability of freeze-dried Lactobacillus bulgaricus B-I was affected by rehydration temperature, and maximum recovery of the viable cells was obtained when they were rehydrated at 20 to 25°C. Cellular ribonucleotides leaked out from the freeze-dried cells during rehydration, but there was no correlation between the viability of cells and the amount of leaked substances. Rehydration of the freeze-dried cells in the presence of RNase caused marked loss of viability. These results suggest that the cell surface was damaged by freeze-drying and its selective permeability was lost to some extent.

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The pathway of the formation of a blue fluorescent substance, harman, and the factors affecting its formation in Saké were studied. Harman content in Sakéwas increased by exposing to UV ray, sun light, visible ray and IR ray or by keeping at high temperature. It was confirmed that harman in Saké was formed by the condensation of tryptophane with acetaldehyde or with serine, especially with acetaldehyde. The formation of harman from tryptophane and acetaldehyde was stimulated at pH 2_??_4 and also by ethanol. This reaction was one of interesting photochemical changes of components in seasoning of Sake.

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Three types of proteinases contained in baker's yeast were fractionated and partially purified by chromatography on TEAE-cellulose and on DEAE-Sephadex. These enzymes were designated as proteinase A, B and C, and some properties of proteinase A and B were described.
A was similar to pepsin and “acid-proteinase” produced by various fungi, but did not hydrolyze carbobenzoxy-L-glutamyl-L-tyrosine. B had milk-clotting activity and proteolytic activity toward casein, and also esterolytic activity toward N-acetyl-L-tyrosine ethylester and α-N-benzoyl-L-arginine ethylester. This enzyme was inhibited by p-mercuribenzoate and diisopropylphosphorofluoridate.

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Yeast proteinase C which shows strong esterolytic activity against N-acetyl-L-tyrosine ethylester was successfully purified from baker's yeast. After repeated chromatography on TEAE-cellulose column, a single elution pattern was obtained regarding protein and the esterolytic activity. The proteolytic activity could not be measured in 0.5% casein solu-tion, but was observed clearly by the use of 4% casein solution as the substrate.
Both of the proteolytic activity and the esterolytic activity were inhibited by the sulf-hydryl reagents such as p-mercuribenzoate and also by diisopropylphosphorofluoridate.

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L-Ascorbic acid, in an acid condition, was degraded to furfural with the formation of 3-deoxy-L-pentosone as an intermediate. Furfural and 3-deoxy-L-pentosone were isolated and identified as 2, 4-dinitrophenylhydrazone and bis-2, 4-dinitrophenylhydrazone, respec-tively.
This acid-catalyzed degradation reaction took place without oxygen and under the storage or cooking condition of foodstuffs. It was shown that aldopentoses and 2-keto-L-gulonic acid themselves were not intermediates of the reaction. D-Araboascorbic acid was also degraded in the same way to furfural and 3-deoxy-D-pentosone.
A mechanism for the non-oxidative degradation reaction of L-ascorbic acid, including the formation of 3-deoxy-L-pentosone and furfural, was proposed.

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Furfural, ethylglyoxal, 2-keto-3-deoxy-L-pentono-γ-lactose and L-xylosone were isolated as their mono- or bis-2, 4-dinitrophenylhydrazones from the degradation solution of dehydro-L-ascorbic acid in 5% sulfuric acid. The mechanisms of the formation of these carbonyl compounds were discussed.
A mechanism of the degradation of dehydro-L-ascorbic acid in 5% sulfuric acid solution, including the formation of 2-furoic acid, was proposed.

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A new imidazolic compound isolated from the reaction mixture of L-rhamnose and ammonia was identified with 4(5)-(L-erythro-2, 3-dihydroxybutyl) imidazole. Consequently, it was inferred that 3-deoxy-L-rhamnosone and formaldehyde were produced as the decom-position products of the reaction of L-rhamnose and ammonia.

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Seven additional components, polyoxins C, D, E, F, G, H and I were isolated from polyoxin complex. They have molecular formulae corresponding to C₁₁H₁₅N₃O₅, C₁₇H₂₃N₅O₁₄, C₁₇H₂₃N₅O₁₃, C₂₃H₃₀N₆O₁₅, C₁₇H₂₅N₅O₁₂, C₂₃H₃₂N₆O₁₃ and C₁₉H₂₄N₄O₁₂, respectively. These polyoxins except inactive polyoxins C and I were highly active against various kinds of phytopathogenic fungi. The close structural similarity among them including polyoxins A and B is also discussed.

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Certain strains of Rhodotorula were found capable of utilizing L-phenylalanine as a sole carbon and nitrogen source and of accumulating ether-soluble metabolite in the cultured broth. The metabolite was isolated and identified as trans-cinnamic acid. The nonoxida-tive deamination of phenylalanine to trans-cinnamic acid was catalyzed by dried cells, acetone-dried cells or intact cells with surface active agents. The distribution of phenyl-alanine ammonia-lyase activity in yeasts was investigated. It was found that the enzyme activity specifically occurred in Rhodotorula and that the formation of enzyme was enhanced by culturing on the medium supplemented with phenylalanine.

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Malonate added to peptone-meat extract medium has been shown to induce maleate cis-trans isomerase in Alcaligenes faecalis IB-14. This enzyme played an indispensable role in the enzymatic production of L-aspartic acid from maleic acid and ammonia.
Though malonate in the medium inhibited the growth of A. faecalis IB-14 to some extent, cells grown in the medium containing 10^-1 M of malonate showed the highest level of the enzyme activity. Specific activity of the enzyme of malonate-grown cells was ap-proximately ten times as strong as that of maleate-grown cells, while, in basal medium-grown cells, cis-trans isomerization of maleate did not occur at all. Maleate was utilized not only as carbon source of the cell growth but also as inducer for the formation of maleate cis-trans isomerase. On the other hand, malonate was not utilized as carbon source and the metabolism of it within the cell was rather restricted within narrow limits. Thus it was concluded that malonate was a gratuitous inducer for the formation of the enzyme, while maleate, which was considerably metabolized, was normal inducer.
It was demonstrated that most of radioactivity of 1-C¹⁴-malonate taken up by cells was localized in particle fraction which sedimented at 105, 000×g for 120 minutes, whereas radioactivity of 1-4-C¹⁴-maleate was uniformly distributed in both particulate and soluble fractions. Maleate cis-trans isomerase activity, in turn, was detected exclusively in soluble fraction in both malonate and maleate induced cells.

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Liver threonine dehydratase and histidase activities of rats fed on a threonine and a histidine imbalanced diets respectively, were measured, each of which was the degradation enzyme of the most limiting amino acid for rats on each imbalanced diet. Rats of the imbalanced groups initially lost their body weight, and began to grow again after a few days. Threonine dehydratase activity decreased by changing from stock diet to the experi-mental diets, and no difference was observed among the control and the imbalanced groups. Histidase activity decreased gradually on the control diet, but, the enzyme activity of the histidine imbalanced group was maintained at the higher level. The inconsistency among the enzyme activities and growth showed that neither the increase of threonine dehydratase activity in threonine imbalance nor that of histidase activity in histidine imbalance would be the main cause of the imbalance.

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1. For the growth of Brev. lactofermentum, oleic acid was completely replaced for biotin; trace amount of biotin was not required. This result applied to the case of many lactic acid bacteria except L. arabinosus.
2. Oleic acid had a growth-inhibitory effect as well as the stimulatory one. This dualistic property was based on the concentration of the acid in the culture medium and was ob-served generally with unsaturated fatty acids irrespective of their chemical structures, com-prising the position and the number of double bond and cis- and trans-form.
3. The growth inhibition caused by higher concentration of oleic acid was changed into the growth stimulation in the three different ways: (a) the prolongation of culture, (b) the esterification of oleic acid, and (c) the addi-tion of the hydrophilic ester of saturated fatty acid as a detoxicant.
4. When added into a medium containing oleic acid, Tween 60 had not only the de-toxificating effect but also synergetic effect; the oleic acid-sparing effect in the presence of small amount of oleic acid and the lag period. reducing effect.
5. The results obtained with Brev. lacta-fermentum confirmed other investigators' ob-servations on the properties of oleic acid and on the relation between saturated and un-saturated fatty acid for lactic acid bacteria.

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The acid-soluble nucleotides were extracted from the tubers of Jerusalem artichoke with perchloric acid, and separated and purified by means of adsorption on and elution from active charcoal, repeated chromatography on columns of Dowex 1 (CI-), followed by paper chromatography. The following nucleotides have been characterized and/or identified: 5'-AMP, 3'-AMP, ADP, ATP, 5'-GMP, 2'-GMP, 3'-GMP, 2', 3'-cyclic GMP, GDP, GTP, 5'-UMP, UDP, UTP, NADP, UDP-glucose, UDP-galactose, UDP-fructose, UDP-N-acetyl-hexosamine and GDP-mannose.^** Neither cytosine ribonucleotides nor deoxyribonucleotides have been detected. The significance of these observations is discussed.

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Novel three-proton signals at δ3.6_??_2.0 in the 60 and 10OMc NMR spectra of helianginone (II) were interpreted by several analytical methods. These protons were concluded to form an isolated ABC system which contains two chemical shifts, δ_AC=100.2 and δ_BC=81.6 cps, and three coupling constants, _JAB=4.9, _JBC=10.2 and _JCA=-14.8 cps. In this system it is very significant that _JCA is negative. These protons were assigned as in the partial structure (a) of II.

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Corynebacterium hydrocarboclastus SIOBI or S489B1 can accumulate a good deal of L-glutamate in a thiamine-deficient medium at the expence of hydrocarbon, but can not form L-glutamate in a thiamine-sufficient medium in spite of rapid cell growth, as already re-ported. In order to establish the optimal culture condition for L-glutamate formation, the influence of the following factors was first studied: hydrocarbon concentration, pH control, nitrogen sources, temperature, aeration and supplement of metal ions or amino acids. Then L-glutamate production from a variety of hydrocarbons or petroleum fractions was examined. Sodium oleate was found to stimulate growth remarkably instead of thiamine. Ferrous ion was found to be obligatory for L-glutamate formation and was suggested to have taken part in the earliest step of n-alkane oxidation.

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