When Aureobasidium pullulans was cultivated with initial pH 6.0 and pH 2.5 in shaking flasks, only a slight difference was observed in the content of lipids in cells. On the other hand, when cultured with initial pH 2.5 in a jar fermenter, the content of lipids in mycelia was larger than that with initial pH 6.0. The content of sugars in the lipids showed a similar tendency. Glucolipids were easily hydrolyzed with dilute acid into glucose, glucooligosaccharide and lipids.

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Aromatic reductones are a group of reagents which split cellular DNA. To survey their cellular specifity, some reductone derivatives were prepared. 3, 4-Dihydroxyphenylglyoxime (II) was obtained by reflux of adrenalone (I) with hydroxylamine in ethanol, in 25% yield.
By nitrosation of I, using N₂O₃ as a nitrosating reagent, mononitroso (III) and dinitroso (IV) compounds were separated from the reaction mixture. Nitrosation proceeded almost quantitatively to yield 70% III and 30% IV.

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Intracellular distribution of NADPH-dependent New Coccine (NC)-reductase from Bacillus cereus T-105 strain was examined. It was found that most parts of the enzyme existed in a cytoplasmic fraction. The enzyme was purified to homogeneity from the cell-free extract about 200-fold by a procedure involving ammonium sulfate fractionation, heat treatment, ion-exchange chromatographies on DEAE-cellulose and DEAE-Sephadex A-50, and Sephadex G-200 gel filtration, and its properties were examined, The visible absorption spectrum of the purified enzyme showed maxima at 375 and 448 nm. The prosthetic group seemed to be a flavin, but has not been identified yet. The optima of pH and temperature for the enzyme activity were pH 7.0 and 40°C, respectively. The enzyme was stable up to 60°C, and 55% of the initial activity remained after heat treatment for 10min at 80°C. The enzyme was stable in a pH range between 6.0 and 8.0 for 7 days at 5°C. The enzyme activity was strongly inhibited by Ag⁺, Hg²⁺, Cu²⁺, Fe²⁺, Fe³⁺, and SDS, but was activated slightly by Mg²⁺. Sulfhydryl reagents such as NEM, PCMB, or IAA, did not inhibit the enzyme activity.

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5-Amino-4-imidazole-carboxamide (AICA)-riboside-hydrolyzing enzyme in Bacillus thiaminolyticus AJ 1366 was induced in the presence of uridine, AICA-riboside, xanthosine and inosine. The optimal concentration of AICA-riboside as inducer was 0.4%. This enzyme was produced in parallel with the growth and inactivated in the stationary growthphase. The substrates were AICA-riboside, adenosine, uridine and inosine. Optimal conditions for hydrolysis of AICA-riboside were pH 7 and at 65°C (40min). This enzyme was the most stable at pH 8.5 and under 60°C (2 hr). AICA-riboside (1%) was completely hydrolyzed in 4 hr with 50% cultured broth in incubation mixture. Permiability-barrier of AICA-riboside into the cell was observed. The existence of two kinds of AICA-riboside-hydrolyzing enzymes, nucleosidase and phosphorylase in this bacterium was suggested.

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A pectinesterase was purified from the culture filtrate of C. rolfsii IFO 6146 by a combination of salting out, gel filtration on Sephadex G-100 and chromatography on DEAE-Sephadex A-50, SP-Sephadex C-50 and hydroxylapatite. The purified enzyme was found to be homogeneous protein by ultracentrifugal analysis. The molecular weight of the purified enzyme was found to be about 37, 000 by the gel filtration. The enzyme was stable over the pH range of 1.1 to 10.0 and retained 90% of its activity when stored at pH 1.1 at 5°C for 72 hr. The maximum activity occurred at pH 2.5 to 4.5 at 45°C. The enzyme was fairly active at a very low pH (1.1) or low temperature (10°C). Hg²⁺ was a potent inhibitor. The enzyme was active not only on high molecular pectin methyl esters but also on low molecular esters. The high enzymatic activity at very low pH values and the unusual tolerance to hydrogen ions are characteristics of pectinesterase from C. rolfsii. The enzyme is one of the acid esterases.

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In the exocarp of eggplant, Solanum melongena L., at least four kinds of proteinase inhibitors were found. These inhibitors were isolated by DEAE-Sephadex column chromatography and isoelectrofocusing. Main inhibitor and one of minor inhibitors showed stronger inhibitory activity for trypsin [EC 3. 4. 21. 4] than chymotrypsin [EC 3. 4. 21. 1]. The pI values were 4.66 for the main inhibitor and 4.06 for the minor inhibitor.
The other minor inhibitors of pl 4.36 and pI 5.98 inhibited chymotrypsin preferably and they had different molecular weights determined by gel filtration from that of the main inhibitor, although these values were very close to each other.

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It was confirmed by means of electron microscopy and differential centrifugation that casein micelles aggregated when concentrated whey protein-free milk (WPF milk) was heated at 135_??_140°C for 15 sec. The amount of large casein micelles, which sedimented at 3000×g or at 12, 000×g, nearly doubled after heating. The casein micelles sedimented at 3000×g in the heated concentrated WPF milk contained smaller amounts of calcium and inorganic phosphorus than those in the unheated one. The κ-casein content of the large casein micelles was low in both the unheated and the heated concentrated WPF milks. The acid caseins prepared from the large casein micelles were more sensitive to the presence of calcium than the whole casein. The κ-casein content of the soluble casein formed by heating was remarkably high, and the soluble casein did not precipitate in the presence of calcium.
From the above results, the large casein micelles were considered certain to be formed from the small casein micelles which released soluble casein upon heating.

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O-Menthyl methylthiocarbamate was treated with boron trifluoride etherate producing S-menthyl methylthiocarbamate (4%) and S-p-menthan-8-yl methylthiocarbamate (56%). On the basis of this result, it was concluded that the rearrangement of secondary O-alkyl thiocarbamates proceeds by S_N1 mechanism whereas primary O-alkyl thiocarbamates rearrange by S_N2.

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The aroma concentrate prepared from sponge cake was analyzed by GC-MS and thirteen compounds including 2, 5-dimethyl-4-hydroxy-3 (2 H)-furanone were identified.
By using several model systems of sponge cake, conditions to produce 2, 5-dimethyl-4-hydroxy-3 (2 H)-furanone, which has a nutty sweet aroma under dilution and is very con tributory to sponge cake flavor, was examined. From a baked mixture of glucose, arginine, egg lecithin and sodium carbonate which had an aroma reminiscent of sponge cake, 2, 5-dimethyl-4-hydroxy-3 (2 H)-furanone was identified. Strongly basic conditions and the presence of oleic acid ester were also effective to produce this compound.

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The coupled bleaching of 2, 6-dichlorophenolindophenol by soybean lipoxygenase-1, was found to occur only under anaerobic conditions with a characteristic lag phase quite unlike the wellknown induction phase associated with lipoxygenase-catalyzed oxidation of linoleate hydroperoxide (LOOH)-free linolelic acid. The duration of this distinctive lag phase was very sensitive to lipoxygenase concentrations and equalled the length of time required for the primary enzyme activity to render the reaction solution virtually anaerobic. The onset of bleaching was marked by a gradual build-up of a ketodiene presumably derived from LOOH. Singlet O₂ and superoxide anion did not appear to be involved in the enzymecatalyzed bleaching while the xanthine-xanthine oxidase system known to produce O₂^- was effective in bleaching DCPIP. It is proposed that the bleaching reaction was a result of an oxidative and irreversible alteration of DCPIP involving a number of reactive oxidants known to be produced anaerobically upon incubation of LOOH and linoleic acid with native lipoxygenase.

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Several Amadori compounds, 1-deoxy-l-L-alanino-D-fructose (DAF), 1-deoxy-1-L-valino-D-fructose (DVF), 1-deoxy-l-(N-γ-aminobutyric acid)-D-fructose (DBF) and 1-deoxy-1-L-prolino-D-fructose (DPF), were pyrolyzed at 200°C for 5min and 1.5 hr respectively. Organic solvent extract of 5min pyrolyzate and volatile product obtained by 1.5 hr pyrolysis were examined. Alkyl pyrazines, pyrrole-lactones such as 2-(5'-hydroxymethyl-2'-formylpyrrol-1'-yl) propinoic acid lactone and 2-(5'-hydroxymethyl-2'-formylpyrrol-1'-yl) isovaleric acid lactone, pyrrole-2-aldehydes, 2-acetyl pyrroles, 2, 3-dihydro-3, 5-dihydroxy-6-methyl-4 H-pyran-4-one, 2, 5-dimethyl-4-hydroxy-3 (2 H)-furanone, 1-formyl and 1-acetyl pyrrolidines, 1-acetyl and 1-acetonyl-2-pyrrolidones, 2-pyrrolidone, 1-acyl substituted 2, 3-dihydropyrrolizines and 5, 6, 7, 8-tetrahydroindorizin-8-one were identified. Isolation and identification of these compounds were made by gas chromatographic and spectroscopic methods (MS, IR, NMR and GC-MS). The aromas of degradation products were evaluated by organoleptic test and the degradation pathway of pyrrole-2-aldehydes were postulated by comparison of the composition of 5min pyrolysis products (product A) with those of 1.5 hr pyrolysis (product B).

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Oerskovia sp. CK produced three types of yeast glucan hydrolases, one of them, F-L lysing viable yeast cells had proteolytic activity and considerable difference was observed between lytic and proteolytic activities in thermal stability. F-L was considered to be a single protein from following results. Both activities were influenced in parallel by acid treatment and inhibitors. The reaction rates of two substrates being added to the enzyme system were less than the sum of the rates of reactions measured separately. Both activities were detected in the same fraction by isoelectric focusing.
On the evidence that F-L lost lytic activity by the heat treatment at 60°C for 15min, we speculated that the enzyme underwent autolysis during heat treatment and binding site for polysaccharide was released, subsequently lost the lytic activity, since active site of F-L remained unaffectedly. These speculations were based on the following results. Difference in specific activity between native and treated F-L was not observed. The specific activity of heat treated F-L purified by gel filtration was 1.6 times more active than that of native F-L. Native F-L had a affinity for dextran but treated F-L lost it. F-L being treated in the presence of DFP was eluted at the same fraction where native F-L was eluted. Based on these results, a model for the yeast cell wall was proposed.

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Effect of heating, freeze-drying, frozen storage and coagulation by chymosin on the exchangeability of colloidal calcium with soluble calcium in milk was investigated by the radioisotopic method previously reported. Heating at 100°C for 30min caused a slight decrease of the exchangeability. Frozen storage at -20°C for 120 days resulted in a marked decrease of the exchangeability accompanying a decrease of soluble calcium. Coagulation by chymosin gave no significant effect on the amount of soluble calcium or on the exchangeability of colloidal calcium.

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Isomeric monohydroperoxides produced from autoxidized methyl linoleate were separated into two geometrical isomers (cis-trans and trans-trans) by silver nitrate TLC. Purified monohydroperoxides were converted into hydroxy octadecadienoates. Trimethylsilyl (TMS) derivatives of these compounds (four components) were separated into three peaks in the gas chromatogram; the mixture of 9-hydroxy-cis, trans-isomer and 13-hydroxy-cis, trans-isomer, 9-hydroxy-trans, trans-isomer and 13-hydroxy-trans, trans-isomer. The trans-trans isomers became more dominant than the cis-trans isomers in the later stage of autoxidation and with the rise of temperature. At the degradation of monohydroperoxides, the decrease of trans-trans isomers was apparently slower than that of cis-trans isomers. It is proposed that cis, trans isomerization of monohydroperoxides takes place at the process of autoxidation of methyl linoleate.

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A series of Tfa-Leu-Y-Z-OMe and Tfa-X-Ala-Z-OMe, in which X, Y and Z are Gly, Ala, Val, Leu, Pro or Phe, were prepared from the corresponding Cbo-tripeptide methyl esters, respectively, and separation of these tripeptide derivatives by gas chromatography (GLC) was studied. It was found that the relationship between the amino acid composition of the tripeptides and their q_i-values (relative retention values) analogous to the case of the dipeptides could be detectable, although there were some marked exceptions within our limited experiments.

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DL-Proline was found to form new diastereoisomeric solid complexes with L-tartaric acid in a molar ratio of 1:1 from an aqueous ethanol. The complex of L-proline was less soluble than that of D-proline. On the basis of these properties, DL-proline was easily resolved by the usual chemical resolution technique without the necessity of converting to the derivative. The optically impure D-proline was racemized by heating at 170°C for 4 hr in water containing an equimolar amount of sodium hydroxide and was reused for resolution step.

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Of 72 soil samples, 10 samples have shown to possess one or more organisms capable of degrading styrene oligomer to some extent. In the course of investigation, dimers are found to disappear rapidly from the culture medium. Trimers, however, are degraded a little and oligomers higher than tetramer not at all. One of the isolates, Alcaligenes sp. 559, grows well on styrene oligomer and is selected for further study. This bacterial strain utilizes unsaturated dimer (1, 3-diphenyl-l-butene) as sole source of carbon and degrades cyclic dimer (1-methyl-3-phenylindane) together. No degradation of trimers by the strain was detected. Furthermore, the assimilation of various aromatic hydrocarbons by this strain was examined and insusceptibility of the oligomers higher than trimer was discussed according to the results.

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Lipid extraction and reconstitution of lyophilized chloroplasts were investigated, by using various extracting solvents; n-hexane, acetone, and their mixtures. With increase of acetone, the solvent extraction caused a more rapid decay of photosynthetic electron flow in chloroplasts, and resulted in less ability of extracted chloroplasts in restoration of activity. Lipid components in hexane extracts of chloroplasts were separated and examined for restoration of photoactivity. α-Tocopherol and plastoquinone A fractions reactivated both Photosystem I and II reactions, while β-carotene and an unknown lipid stimulated preferentially Photosystem I reaction. The unknown lipid was found in chloroplast as a minor component, and suggested to be a new wax ester.

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Two compounds were isolated from alfalfa. Their structures were determined as benzoyl meso-tartaric acid (I) and benzoyl (S), (-)-malic acid (II) respectively. They were found in nature for the first time.

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Changes in lipid component and fatty acid composition of axis (hypocotyl and epicotyl) and root of germinating soybeans grown either in the dark or the light were investigated. The growths of the axis and root in plants, and their lipid content were higher in the lightgrown seedlings than in the dark-grown ones. The main lipid components in the axis were non-polar lipids at the initial stage of germination, but polar lipids became predominant at the later stages. The major lipid components in the root were polar lipids during germination, the minor ones being non-polar lipids.
An increase of the polar lipid content in the two tissues, which depended on the growths of plants, was observed. During germination of soybean seeds, the percentage of glycolipids increased in axis and decreased in root, whereas that of phospholipids increased in root and decreased in axis. Changes in the lipid components of the two tissues during germination were higher in the light-grown seedlings than in the dark-grown ones. The changes in the fatty acid compositions of axis were marked in comparison with those of root, and the percentage of linolenic acid of glycolipids in axis markedly increased in the light-grown seedlings.

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Bacillus vitellinus, a butirosin-producing organism, was shown to possess butirosin 3'-phosphotransferase catalyzing the phosphorylation of butirosin A into butirosin A 3'-phosphate.
The enzyme was purified about 1200-fold from the cell-free extract of the organism by ammonium sulfate fractionation, affinity chromatography on butirosin A-Sepharose 4 B and two gel filtrations on Sephadex G-100.
The molecular weight of the enzyme was estimated to be about 30, 000 by gel filtration. The pH optimum was between 6.7 and 8.8. Mg²⁺ was required for maximal activity and could be partially replaced by Co²⁺. ATP and GTP were effective phosphoryl donors. The enzyme catalyzed the phosphorylation of aminoglycoside antibiotics such as butirosin A, butirosin B, xylostasin, ribostamycin, neomycin, paromomycin, kanamycin A and kanamycin B. The Km values for butirosin A and ATP were 4.0×10^-6M and 5.6×10^-5M, respectively. The enzyme was strongly inhibited by p-chloromercuribenzoate, Ag⁺ and Hg²⁺, and was competitively inhibited by 3'-deoxybutirosin A.

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A method for purification and crystallization, and some properties of ribonuclease from Aspergillus sp. [EC 2. 7. 7. 17] (RNase L) are reported. The purification procedure consisted of six steps, including acetone precipitation, column chromatographies on Duolite A-2 and DEAF-cellulose, repeated chromatography on DEAE-Sephadex A-50 column and affinity chromatography on 5'-AMP-Sepharose 4 B column. Crystallization was performed by the dialysis against ammonium sulfate solution at 60% saturation.
The crystalline enzyme was shown to be homogeneous by polyacrylamide disc electrophoresis and ultracentrifugation. Svedberg value of the crystalline enzyme was 4.2. The enzyme was the most active at pH 3.5 and 60_??_65°C, and it was inhibited markedly with Fe.³⁺
RNase L has no absolute base specificity, and produces four kinds of 3'-mononucleotides from yeast RNA. However, the susceptibility of four nucleotide residues to RNase L increases in the order; G<A<C<U and is quite different from those of RNase T₂, RNase M and RNase R.

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Diffusion coefficients of saccharides and amino acids were measured in cross-linked polymers such as dextran gels, polyacrylamide gels and photo-crosslinkable resins of different gel concentrations or various degrees of crosslinkage. Comparison of diffusion coefficients in gels with those in polymer solutions indicated that the diffusional velocity in gels was restricted not only by the interaction between diffusing substances and gel components but also by the steric hindrance of gel matrix. The diffusion coefficients in dextran gels and polyacrylamide gels were appreciably lower than those in polymer solutions, and the degree of lowering depended on both the gel concentration and the size of diffusing substances. The photo-crosslinkable resins basically composed of polyethylene glycol showed a higher permeability than dextran and polyacrylamide gels on account of a weak interaction between diffusing substances and resin component. Furthermore, an attempt was made to correlate the decrease of diffusion coefficients in gels with the diffusion coefficients in polymer solutions and the distribution coefficient of the diffusing substances.

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