Seven strains of acetic acid bacteria which can produce a new type of extracellular soluble polysaccharide were isolated from vinegar mash. All of the strains were classified into the genus Acetobacter.
The polysaccharide was composed of glucose, galactose, mannose and glucuronic acid in an approximate molar ratio of 6:2:1:1. Sugar components and their ratios were found to be independent of the carbon source used for cultures. We also found that the polysaccharide was produced by Acetobacter pasteurianus subsp. estunensis IFO 13751 and "Gluconobacter capsulatus" IAM 1813 in shaking cultures although only in very small amounts.

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Saccharomyces rouxii is a salt-tolerant yeast, industrially important for miso- and shoyu-making. The change of intracellular lipid composition was examined in shaken cultures of S. rouxii ATCC 42981 grown in medium containing various concentrations of NaCl. Increases in sterolesters and free fatty acids and a decrease in triacylglycerol were observed on adding 1 M or 2M NaCl to the medium. With an increase in NaCl concentration to 3M, sterol-esters decreased, triacylglycerol increased, and free fatty acids increased further. An increase in oleic acid and the decrease in linoleic acid were found with an increase in NaCl concentration. Effects of NaCl similar to these were also recognized in other strains of S. rouxii. The shape of S. rouxii cells changed from spherical to ellipsoidal with an increase in NaCl concentration. The size of cells was observed microscopically to be smaller in 2M and 3M NaCl-media than in OM and 1M NaCl-media.

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Brewer's yeast appears to flocculate or disperse reversibly in response to the environmental conditions. The yeast and its solubilized cell surface substance show flocculation-dispersion changes according to pH, sugar concentration and flocculation inducing substances. Top fermentative yeasts do not show such a response to the surrounding conditions. Cell surfaces of bottom fermentative yeasts increase in hydrophobicity during a shift from fermentation starting conditions (dispersion of yeast) (high sugar concentration, pH 5.5) to ending conditions (flocculation) (no sugar, pH 4.2), but this hydrophobicity increase was not seen in the case of top fermentative yeast cells. The contributions of hydrophobic interaction and ionic bonds to flocculence of the yeast were discussed.

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α_s1-Casein can be made either soluble or insoluble by adjusting the concentration of coexisting calcium ions. In this study, we tried to make a soluble-insoluble interconvertible enzyme through the formation of a conjugate of an enzyme and α_s1-casein using a heterobifunctional crosslinking reagent, N-succinimidyl 3-(2-pyridyldithio)propionate. The conjugate of phosphoglyceromutase and native α_s1-casein did not exhibit sufficient calcium-dependent precipitation. However, conjugates of enzymes (phosphoglyceromutase, enolase or peroxidase) and α_s1-casein polymerized by transglutaminase precipitated almost completely in the presence of more than 50mM CaCl₂. Most of the enzyme conjugates precipitated as calcium casemates could be solubilized reversibly with EDTA, without a significant loss of activity. A mixture of the enzymea-polymerized α_s1-casein conjugates prepared with phosphoglyceromutase, enolase and pyruvate kinase could catalyze sequential reactions which convert D-3-phosphoglycerate into pyruvate with the same efficiency as a mixture of free enzymes. These results indicate that conjugates of enzymes and polymerized α_s1-casein can be useful as soluble-insoluble interconvertible enzymes.

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The cadmium (Cd) tolerance of 41 strains of halophilic bacteria with different saltrequirements was surveyed. Their tolerances showed the vast range of from below 50 to 2, 500μg CdCl₂ per ml, and a highly Cd-tolerant, moderately halophilic Pseudomonas sp. No. 40 was found. The effects of the concentrations of NaCl, NaNO₃ and Na₂SO₄ on the Cd-tolerance of the bacterium were examined by turbidity measurement and viable counting. It was noted that the Cd-toxicity was greatly affected by the NaCl concentration of the medium : poor growth was seen at 2, 000μg CdCl₂ per ml and no growth at 2, 500μg CdCl₂ per ml in 1M NaCl medium whereas moderate growth was observed in 2 to 4M NaCl medium containing 2, 500μg CdCl₂ per ml, showing a decrease of the Cd-toxicity with an increase in the NaCl concentration. On the other hand, the Cd-toxicity was apparently enhanced by NaNO₃ and Na₂SO₄ : the bacterium failed to grow at as low as 200μg CdCl₂ per ml in 1 to 2m NaNO₃ medium or at 500μg CdCl₂ per ml in 1M Na₂SO₄ medium. Also, the toxicity was measured as cell death, and accommodation to Cd required an extended lag time that varied with both the concentration of Cd and that of salts.

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The effects of lipids on rheological characteristics and appearance of heat-induced soybean protein gels were investigated, and these properties were related to a protein-lipid interaction. The hardness of soybean oil-supplemented gels increased as the level of lipid addition increased. On the other hand, the same parameter of lecithin-supplemented gels increased with low deformation (<20%), but decreased with greater deformation (>60%) in the region above the yield point. Uniaxial compression test results revealed that inclusion of lipid materials enhanced the heat-induced gelation of a soybean protein. The lipid free gels had a dense packing structure with small globules as judged from scanning electron microscopic images. Soybean oil-supplemented samples had a sponge-like ultrastructure, whereas lecithin-supplemented gels exhibited a network structure. These results suggested that the crosslinks were joined by both short stiff chains and longer flexible chains in neutral lipid-supplemented gels, whereas crosslinks joined by both short stiff chains and longer limper chains existed in polar lipid-supplemented samples.

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P. vulgaris seed protein was extracted with 85-95% efficiency, mildly without precipitation or low ionic treatment. No distinct '11-12S, ' '28S, ' nor '33S' (which were reported before) was observed by ultracentrifuge analyses of 11 varieties. The main components, '7S' and 18-19S' in acidic solutions, were separated with Sepharose 6B chromatography into peak 2 (P2) and peak 1 (P1), respectively. P1 seemed to correspond to G1 (one of P. vulgaris main proteins). Following DEAE-Sepharose chromatography eliminated a part of the minor components from P1. Sedimentation coefficients, dissociation-association behavior, and molecular weight of P1 were studied.

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Coriolus versicolor KY2912 grown on a medium containing glucose, sucrose or glycerol produced pyranose oxidase. Pyranose oxidase (glucose-2-oxidase) was purified by HPA-75 chromatography, Sepharose 4B and Sephadex G-100 gel filtration, and hydroxyapatite chromatography. The purified enzyme preparation showed a single protein band on acrylamide gel electrophoresis. The highest activity was obtained when D-glucose was employed as substrate and molecular oxygen as electron acceptor. The enzyme was most active at pH 6.2 and 50°C, stable in the pH region between 5.0 and 7.4, and the activity was completely lost above 70°C. The activity was inhibited by Ag⁺, Cu²⁺ and PCMB. The enzyme contained FAD covalently bound to the polypeptide chain. The enzyme consisted of identical subunits with a molecular weight of 68, 000, and showed a total molecular weight of 220, 000.

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S-Methylmethionine (MMS, an anti-ulcer factor, Vitamin U) was determined in the extracts of various kinds of teas, such as green teas, black teas and oolong teas, using an amino acid analyzer for physiological-fluid analysis or for rapid analysis. MMS in the column eluates was confirmed to be dimethyl sulfide by a gas-chromatographic method with a flame photometric detector. The quantity of MMS obtained from the various green teas depended on the quality and the freshness, i.e. fresh, high-quality gyokuro, 15.7 to 24.5mg% ; fresh sen-cha, 7.0 to 10.3mg% ; and the other green teas 1 to 6mg%. Oolong tea and black tea did not contain MMS.
The extraction conditions for and the heat-stability of MMS were also discussed.

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The enantiomers of α-benzylidene-γ-methyl-γ-butyrolactones, a novel class of fungicides, were prepared stereospecifically from (R)- and (S)-γ-methyl-γ-butyrolactones. The results of their fungicidal evaluation are also described.

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Rubusoside, the β-D-glucosyl ester of 13-O-β-D-glucosyl-steviol which was isolated from leaves of Rubus suavissimus collected in China as the major sweet principle (yield : 5.4%), was subjected to α-14 transglucosylation with the cyclodextrin glucosyltransferase produced by Bacillus megaterium Strain No. 5 using soluble starch as a donor. A significant improvement in the quality of sweetness was observed for the crude reaction mixture, which was separated into mono-, di-, tri-, tetra-, penta-, and hexa-glucosylated products. All isomers of the mono- and di-glucosylated products were further separated. Evaluation of the sweetness of these products compared with stevioside, rebaudioside A, etc. disclosed that the ratio of the number of glucose units at the 13-hydroxyl group to that at 19-carboxyl group seems to have a significant relationship with the sweetness as well as the quality of taste for glucosides of this type.

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Microbial oxidations of n-tetradecane, tetradecanols and tetradecanoic acid were investigated by using intact cells of Corynebacterium equi, a hydrocarbon-assimilating bacterium, in an aqueous phase and organic solvents. The bacterial cells were hydrophobic and could be well dispersed in all organic solvents employed to give homogeneous reaction mixtures, and among them, isooctane was found to be the best for the reaction. n-Tetradecane and tetradecanoic acid were completely oxidized in the aqueous phase, but not in isooctane. In contrast, 1-tetradecanol was oxidized much more readily in isooctane than in the aqueous phase, and an oxidation product identified as myristyl myristate was accumulated in isooctane at the conversion rate of 80%. 2-Tetradecanol was also readily oxidized in isooctane, and 2-tetradecanone was obtained at the conversion rate of nearly 100%.Similar results were obtained when toluene and n-hexane were used as the solvent in place of isooctane, while no reaction was observed when chloroform was employed.

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The enantiomers of 4-dodecanolide, a defensive secretion of rove beetles, were synthesized from (S)- and (R)-2-aminodecanoic acid obtained by the enzymic resolution of the corresponding chloroacetyl derivative.

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(R)-2-(4'-Isobutylphenyl) propanoic acid (ibuprofen), (S)-3-(4'-isobutylphenyl) butanoic acid and (S)-4-(4'-isobutylphenyl) pentanoic acid were obtained using microbial oxidation of (±)-lisobutyl-4-(1'-methyloctyl) benzene by Rhodococcus sp. BPM 1613.

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(3S, 4S)-(-)-4-Methyl-3-heptanol, the key compound in the aggregation pheromone of Scolytus multistriatus Marsham, was synthesized by employing asymmetric epoxidation and epoxide cleavage with trimethylaluminum as the key steps. (3S, 4R)-(+)-4-Methyl-3-heptanol was also synthesized.

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Previous structural studies of less-polar dimers in autoxidized methyl linoleate (ML) have been extended to polar dimers. After isolation by successive silicic acid and gel permea tion chromatography, the dimeric fraction of linoleate was separated into two major fractions, A₁ and A₂, according to their polarities. The polar dimers (A₁) were further fractionated by HPLCeither directly or after reduction with triphenyl phosphine on a micro silica column. Isolated sub fractions were characterized by UV, IR, GC-MSand FD-MS after suitable derivatizations. FD-MS of all these dimers showed a molecular ion peak which corresponds to 2×ML+ 6×O and the reduction of each sub fraction with stannous chloride gave equimolar amounts of 9 and 13-hydroxy octadecadienoate, and 9, 10, 13 and/or 9, 12, 1 3-trihydroxy octadecenoate. These results combined with others show that the A₁ dimers are composed of isomeric mixtures containing a peroxide bridge linking a methyl octadecadienoate and a 9, 12 and/or 10, 13-dihydroperoxy octadecenoate across C-9 and/or 13 on each of them.

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A simple and specific method is described, for the determination of propylene glycol (PG) in commercial foods. The method is based on the oxidation of PG by propylene glycol dehydrogenase (PGDH) from Microcyclus eburneus, which is accompanied by the reduction of NAD⁺ to NADH.
PG separated from foods by extraction with deionized water and ultra filtration was readily determined by measuring the absorbance at 340nm.
The use of an enzymatic reaction resulted in almost stoichiometric oxidation of PG, and the method was relatively free from interference. Recoveries of 2 and 10mg/g of PG from several foods ranged from 85 to 95% for 2mg/g and 95 to 99% for 10mg/g with a detection limit of 2μg.

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The chemical constituents of calluses of Thujopsis dolabrata (Hiba), Chamaecyparis obtusa (Hinoki), Chamaecyparis pisifera (Sawara), and Platycladus orientalis (Konotegashiwa), all of which belong to Cupressaceae, were examined by GC analysis. The main components of these calluses were diterpenoids of an abietane-type and sitosterol in common, while the chemical constituents of these parent plants were different from each other.

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Purification and separation of eight steroidal plant-growth regulators, dolicholide, dolichosterone, homodolicholide, homodolichosterone, brassinolide, castasterone, 6-deoxocastasterone and 6-deoxodolichosterone, from immature seed of Dolichos lablab were accomplished using various chromatographic techniques. The reversed-phase HPLC of a number of steroidal plant growth regulators was also studied.

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A biomimetic synthesis of (-)-aplysistatin (1) is described. The Wittig reaction of the keto ester 5 with homogeranyl triphenylphosphonium ylid gave the desired intermediate 3. Successive treatment of 3 with activated manganese dioxide, sodium chlorite and aq. trifluoroacetic acid led to the unsaturated β-hydroxy lactone 2, which was subjected to brominative cyclization to yield (-)-aplysistatin (1).

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Glucokinase was purified from Escherichia coli B cells dosed with a hybrid plasmid carrying the gene for glucokinase. The enzyme was purified about 170-fold and was homogeneous on polyacrylamide gel electrophoresis. The enzyme was 49, 000 in molecular weight and consisted of two subunits having a molecular weight of 24, 500. The glucokinase catalyzed phosphorylation of D-glucose, D-mannose, D-glucosamine, and 2-deoxy-D-glucose, consuming ATP as a phosphoryl donor. Besides ATP, other nucleoside triphosphates such as ITP, GTP and UTP were also utilized as phosphoryl donors. The enzyme required free sulfhydryl groups and Mg²⁺ for activity. Other properties of the glucokinase were characterized and compared with those of glucokinases from various sources.

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2-Nitropropane dioxygenase, purified to homogeneity by an improved method from a yeast, Hansenula mrakii, has a molecular weight of 42, 000, and consists of a single polypeptide. The enzyme contains 1 mol of FAD per mol of enzyme. The iron protein associated with previous preparations was removed by the present purification procedures. The enzyme catalyzes the oxygenative denitrification of anionic nitroalkanes much more effectively than that of the neutral ones with the optimum pH of 6.5. The Michaelis constants for the anionic substrates are as follows : 2-nitropropane, 1.61mM; 1-nitropropane, 3.23mM; nitroethane, 3.13mM, and 3-nitro-2-butanol, 0.59mM.

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To establish a DNA uptake system in coryneform bacteria, transfection of Corynebacterium glutamicum was studied. Although normal cells of C. glutamicum could not be transfected, protoplasts of C. glutamicum T-42 could be transfected with DNA of temperate phage Φcg1. Transfection was detected by the formation of plaques on a protoplast regeneration medium onto which soft agar was overlayed with transfection mixtures. Divalent cations such as CaCl₂ were essential for transfection. Polyethylene glycol stimulated the efficiency of transfection about a thousand-fold. Under optimum conditions the efficiency was 9×10^-2 transfected cell per input cell. Besides C. glutamicum T-42, other glutamic acid producing bacteria could also be transfected with φCG1 DNA at various frequencies.

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The absolute configuration of betaenone D (1), a metabolite of Phoma betae Fr., was determined by the application of the CD exciton chirality method to the benzoate derived from betaenone D.

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(+)-Hexylitaconic acid was isolated as a root-growth stimulating substance from a culture filtrate of Aspergillus niger K-88.

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