Tomato cell wall fraction washed three times with water was used as a preparation of insoluble β-fructofuranosidase (β-FFase). The insoluble β-FFase could not be released from cell wall fraction in the presence of substrate.
Comparative studies on kinetics of soluble and insoluble forms of β-FFase were performed.
There were no marked differences between the two forms with regard to pH dependency, Michaelis constant and some inhibitors.
Considerable difference was observed between the two forms in both temperature sensitivity and dependency. The soluble form was no longer active at 55°C, but the insolubleform still retained 65%, of the maximum activity at this temperature. There was a marked break in the Arrhenius plot at 19°C with the insoluble form, but a linear line was obtained at a temperature range of 10°C to 30°C with the soluble form. Activation energies were 10, 800 and 17, 300 cal/mole in the lower temperature range (below 19°C) for the insoluble and the soluble form, respectively. But they differed widely at higher temperatures (above 19°C); i.e., 53, 600 and 17, 300 cal/mole, respectively.

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Previously, some changes were noticed in energy metabolism of rats fed a low casein diet. In connection with these phenomena, influence of a low casein diet on the composition and amounts of free fatty acids in liver homogenate after autolyzing for a few hourswas investigated. For the measurement of free fatty acids, they were purified by a methodwith some devices in purification procedure using KOH. It was found that amounts offree fatty acids in liver homogenate after autolyzing for a few hours were lower in ratsfed _??_ low casein diet.

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The assimilation of sodium cyclamate (CHS-Na) by microorganisms was studied. Fif-teen strains of cyclamate-assimilating bacteria were isolated from the feces of guinea pig excreting cyclohexylamine (CHA) in urine. The majority of the strain isolated seems to belong to the genera Pseudomonas and Corynebacterium. All strains were able to assimilate CHS-Na as a sole source of carbon and nitrogen, and accumulated clearly CHA in the culture medium. It was confirmed with the cell-free extract that the strains possessed the enzyme system which formed cyclohexanone (CHnone) from CHS-Na via CHA. It seems that the desulfation of CHS-Na to CHA is catalyzed by hydrolase, and that the deamina-tion of CHA to CHnone is catalyzed by amine oxidase depending on oxygen.

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Both whipping and emulsifying properties, the characteristic functional properties of soybean products, were investigated by using the commercial products in Japan. Whipping properties of the soybean products, expressed by foam expansion and foam stability, were found to correlate with water dispersible nitrogen, and the resultant foams were stable when the dissolved proteins were native. Thus, the native defatted soybean flour which contained native and soluble protein exhibited excellent whipping property. Emulsifying properties correlated positively with protein and negatively with fiber contents. As soybean protein isolate and soybean protein extract are rich in protein and poor in fiber contents, both of them show good emulsifying functions.

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A survey of the baking behavior of commercially available soybean products was carried out to estimate their effects on dough properties by using farinograph. The parameters read on the farinogram are classified into two groups by the principal component analysis; one is concerned with dough stability and the other with water absorption.
It was found that the addition of soybean products at level of 5% to wheat flour, in general, make the characteristics of flour stronger, i.e., increasing both stability and water absorption. The dough stability correlates positively with the amount of native protein of soybean product and, consequently, some native defatted soy flours perform the effective functions in this respect. The water absorption of dough has positive correlation both with the protein content and with the protein dispersibility of added soybean products, and negative correlation with the amount of native protein. The danatured but soluble soy protein isolate is, therefore, effective for increasing the water absorption of dough.

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Large amounts of food-grade soybean products are consumed in fish product industries in Japan. To clarify the properties of soybean products desirable for fish processing, the kamaboko added with soybean products were evaluated by both sensory testing and instrumental measurements. The correlation between the suitability of soybean products for kamaboko and the basic chemical and functional properties of the soybean products was discussed. It was found that the “hardness” of the kamaboko added with soybean products correlated highly with the degree of denaturation of soy protein and with the amount of nitrogen of soybean products not dispersible in 3% sodium chloride aqueous solution.
It was also estimated that the textural properties of kamaboko added with soybean products could not be deduced from the textural properties of heat-coagulated gels of the corresponding soybean products.

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Distribution of NAD phosphorylating reactions, phosphorylation through NAD kinase and phosphotransferase, was investigated. NAD kinase activity was distributed rather widely in bacteria, whereas phosphotransferase activity with p-NPP and NAD was limited to a few genera. Proteus mirabilis showed strong activity of phosphotransferase besides NAD kinase activity.
Partial purification of the phosphotransferase was attempted. The enzyme preparation possessed phosphatase activity as well as phosphotransferase activity. Phosphorylation of NAD proceeded maximally under the conditions below pH 4.0. Cu²⁺ showed stimulating effect on the activity. Besides p-NPP and phenylphosphate, various nucleotides, especially 2' (or 3') isomers, served as excellent phosphoryl donors, and various kinds of nucleosides and nucleotides were phosphorylated to form nucleoside monophosphates and nucleoside diphosphates.

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Preventive effect of dl-α-tocopheryl acetate against nutritional encephalomalacia induced by dilauryl succinate was compared by feeding experimental diets containing various levels of dilauryl succinate to 2-week-old chicks which were deprived of their body reserve of vitamin E in advance. Incidence of encephalomalacia increased in parallel with the increase in dietary dilauryl succinate and with the decrease in dietary dl-α-tocopheryl acetate. The linear relationship as described by the following equation
y=0.258x-11.8,
was observed between 50% effective dietary level of dl-α-tocopheryl acetate (ymg/kg) and dietary level of dilauryl Succinate (xg/kg).
Possible direct role of dl-α-tocopheryl acetate in metabolism of 12-carbon compounds was discussed.

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A mucilage extracted from tubers of Dioscorea batatas Decne, forma Tsukune with cold water has been found to contain a mannan associated firmly with protein. A water-insoluble mannan ([α]D-31°, formic acid), isolated from the mucilage by formation of copper hydroxide-complex, is a β-(1→4)-linked D-mannan of _??_ 110. Mlethylation and periodate oxidation studies indicated that it has a small degree of branching at the C-3 positions of the mannose residues, one out of 10_??_11 units. The oligosaccharides, separated from the enzymic digest of the mannan, were characterized by methylation analysis to be 4-O-β-D-mannosyl-D-mannose, and O-β-D-mannosyl-(1→4)-β-D-mannosyl-(1→4)-β-D-mannose.
The native mannan ([α]D-30.6° in water), isolated from the mucilage after degradation of the protein moiety with _??_ proteolytic enzyme, was homogeneous and had molecular weight 23, 000 (sedimentation analysis). It is partially acetylated (O-acetyl, 14.2%), most probably at the C-2 and/or C-3 positions.
On the basis of these findings, the constitution of the mucilage has been discussed.

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A strain of soil bacteria was isolated by elective culture with bergenin, a C-glucoside having dihydroisocoumarin structure, as a sole carbon source, and was identified as Erwinia herbicola. In growth or replacement medium, the bacterium degraded bergenin to yield at least two major degradation products, one of them being identified as 4-O-methylgallic acid (compound I), an agivcone of bergenin. The bacterium seemed to utilize the sugar moiety of bergenin preferentially as carbon and energy sources, since the rate of further transformation of compound I by the bacterium was slow. In replacement culture with compound I, gallic acid was detected as one of the metabolites. A possible pathway for microbial degradation of bergenin is proposed.

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1. Aminoacyl tRNA synthetase was extracted from the silkgland of silkworm (Bombyx mori LINNÉ) and fractionated on a DEAE-cellulose column. Activities were estimated by ATP-PPi exchange reaction as well as glycyl tRNA formation.
2. Two peaks, A and B, having ATP-PPi exchange activity were found in the separated fractions, respectively. There was also observed a marked difference between the both peaks with respect to the pH optimum and activity dependence on MgCl₂ concentration.
3. Peak A showed no activity of glycyl tRNA formation. Only a part of peak B coincided with the activity of glycyl tRNA formation. The activities of both the ATP-PPi exchange reaction and glycyl tRNA formation were found to be dependent on MgCl₂ concentration, and the optimum concentration was different between two peaks.
4. It also seemed to exist two peaks of activities, a and b, in glycyl tRNA formation which could be separated with _??_ DEAE-cellulose column.

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The cells of a strain of Streptornyces sp. previously grown in a peptone-glucose medium were incubated with hypoxanthine in a mixture consisting of K-phosphate buffer (pH 7.0), Mgcl₂ and glucose. Two ultraviolet absorbing substances were found to be accumulated in the mixture. One of them was identified as xanthine and the other as 6, 8-dihydroxy-purine from their ultraviolet absorption and chromatographic characteristics. During a further incubation, both of them disappeared from the mixture and were found to be oxidized to uric acid. Thus, the simultaneous operation of two metabolic pathways, hypoxanthine→xanthine→uric acid and hypoxanthine→6, 8-dihydroxypurine→uric acid, was suggested for the oxidation of hypoxanthine by this microorganism. When the cells were incubated with hypoxanthine in the presence of chloramphenicol, xanthine and 6, 8-dihydroxypurine were accumulated in the mixture and the amount of xanthine decreased during a prolonged incubation as in the absence of the antibiotic. However, 6, 8-dihydroxypurine did not decrease and uric acid was accumulated in the mixture with chloramphenicol. These oxidation pathways of hypoxanthine were found in a wide variety of Streptomyces. The enzymes which would participate in the pathways and the formation of these enzymes are discussed. A liquid chromatographic determination of hypoxanthine, 6, 8-dihydroxypurine, xanthine and uric acid using an anion exchanger column are described.

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The alkylation of α, β-unsaturated esters with n-butylbromide gave stereoselectively α-butyl-β, γ-cis-unsaturated esters in the presence of alkali amide in liquid ammonia. On the other hand, the alkylation of β, γ-cis or trans-unsaturated esters afforded α-butyl-β, γ- cis or trans-unsaturated esters with retention of configuration. These alkylations provide a new synthetic method of preparing α-alkyl β, γ-cis or trans-unsaturated esters.

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The reaction of dialkylchloramines with N-dialkyl-substituted aminoisobutenes was shown to give a mixture of the two α-dialkylaminoaldehydes, which were derived not only from the addition of chloramine, but also from the rearrangement of amino group in the parent enamines. The results suggested an ionic path involving _??_ cyclic dialkylaziridiniurn ion as intermediate. The possible mechanism of these reactions was discussed.

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Investigations were carried out to detect a blocked step in the glycerol biosynthesis of the glycerol auxotroph GL-21 derived from Corynebacterium alkanolyticum No. 314.
The enzyme required for the conversion of dihydroxyacetone phosphate to α-glycero-phosphate was assumed to be defective, because some of glycerol derivatives and glycerol analogues substituted for glycerol as a growth factor, in which glycerides, phospholipids, surfactants and intermediary metabolites in the glycolysis pathway were included.
To confirm this assumption, the activities of α-glycerophosphate dehydrogenase of the mutant were compared to those of the parent. From these results, the auxotroph GL-21 was found to be deficient for _??_ specific L-glycerol-3-phosphate: NADP oxidoreductase which is indispensable for the synthesis of glycerol.

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Methyl 2-benzimidazolecarbamate was found as a major metabolite of thiophanate-methyl fungicide, dimethyl 4, 4'-o-phenylenebis (3-thioallophanate), in or on bean plants. The metabolite, originally detected by TLC-autoradiogram during the biotransformation study of radiolabeled thiophanate-methyl, was isolated in crystals from a water culture medium of the plant or the plant homogenate to which thiophanate-methyl had been added. IR, NMR and Mass spectra of the crystals were identical with those of the synthetic standard.
Similarly, we confirmed that thiophanate (ethyl analogue) was transformed into ethyl 2-benzimidazolecarbamate.

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The cell-lysis of Micrococcus lysodeikticus by egg-white lysozyme was inhibited by some nonpolar hydrocarbons such as n-butane, isobutane or propane. The lysozyme-induced cell-lysis was, however, no longer inhibited when the same hydrocarbons were added after the cell-lysis had already begun. Bubbling air through the cell suspensions, in which the lysozyme-induced cell-lysis had been inhibited in advance by the hydrocarbons, restored the event of cell-lysis to some extents. The Lineweaver-Burk plots indicated the kinetics of competitive inhibition of the lysozyme-induced cell-lysis by these hydrocarbons. From these results, the gaseous hydrocarbons were assumed to exert little influence on the enzymatic activity of egg-white lysozyme itself, that is the hydrolysis of β-1, 4-glucosaminide linkage of the mucopeptide chain in the cell wall, but inhibit competitively the binding of lysozyme to the cells.

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The fractionation pattern of OMG₀, ovomucin gel(B) in fresh egg white, by density gradient column electrophoresis showed two peaks. Each peak was shown to migrate as a single component, with a mobility of either the fast or slow moving component of ovomucin gel(B). Each peak was named as F-component and S-component.
Carbohydrate and sulfate contents of F-component were much higher than these of S- component. The carbohydrate content of F-component and S-component was found to be about 50 and 15 percents of dry matter, respectively. Serine and threonine contents in F-component were much higher than those in S-component.
The fractionation pattern of OMG₂₀, ovomucin gel(B) in egg white stored for 20 days at 30°C, by density gradient electrophoresis showed only one peak which corresponded to S-component, and that of OMS₂₀, ovomucin sol (B) in egg white stored for 20 days at 30°C, showed two peaks which corresponded to F- and S-component.
Ability of F-component to interact with lysozyme was greater than that of S-component.

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The phosphatidate formed by glycerol 3-phosphate acyltransferase present in a particulate fraction from E. coli remained associated with the particulate material and was converted to phosphatidylethanolamine and phosphatidylglycerol by other enzymes contained in the particulate fraction. Those enzymes required a heat-labile factor for the synthesis of phosphatidylethanolamine and a heat-stable factor for the synthesis of phosphatidylglycerol. Both of these phospholipids like their precursor remained bound to the particulate fraction.

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Two diastereomers of 6-bromo-l, 2, 3, 4, 5-pentachlorocyclohexane were synthesized from the DL (36/45)^#2-diasstereomer of 3, 4, 5, 6-tetrachlorocyclohexene (α-BTC) and the DL (346/5)^#2-diastereomer (γ-BTC) by several stepwise routes. Both of these new products were shown to have the configuration of lindane^#3 by NMR studies at 300 MHz^#1 and by the synthetic routes. Three diastereomers of 6-bromo-3, 4, 5-trichlorocyclohexene were also prepared and the configurations determined partly by means of 300 MHz NMR.

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A survey of the toxin production by several strains of blast fungus was carried out. Among the strains tested only one strain, C₁ (THU 69-03) produced α-picolinic acid with good yield and other strains produced neither α-picolinic acid nor piricularin. On the other hand, tenuazonic acid and its Fe-chelate compound were isolated as novel blast fungus toxins from the surface culture brothes of these strains, but they could not be isolated from the shaking culture brothes. The phytotoxic effect of tenuazonic acid on rice plants in regard to varietal difference was also studied.

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