It was found that there are two types of saccharases developed in the aged slices of sugar beet root. One of them was soluble enzyme and another was insoluble saccharase bound to the cell wall. The hydrolysis of sucrose was largely due to the actinity of the bound type-saccharase. By treating the cell wall with NaCl, KCl, NaNO₃, KNO₃ or Na₂SO₄ solutions, the bound enzyme was liberated and subsequently solubilized. The concentra-tion of NaCl or KCl more than 0.3M and of MgSO₄ more than 0.1M were required to solubilize the enzyme.
The maximum activity of the bound saccharase was found to be at pH 4.6 and was stable at pH values from 4.0 to 7.0. The enzyme was inactivated by the preincubation at 45°C for 15min. The Km value was determined to be 1.53mM for sucrose. The en-zyme was considerably inhibited by HgCl₂, FeSO₄ and PCMB.

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A series of experiments was conducted to reevaluate the phenylalanine requirement of the growing chick fed an amino acid diet containing 20% of amino acid mixture for 10 days from the 7 th to 17 th day. The effect of varying the level of phenylalanine and tyrosine in the diet on plasma free phenylalanine and other amino acids and the oxida-tion of phenylalanine were also studied.
When the diet contained 0 and 0.63% tyrosine, the caluculated phenylalanine require-ments from the daily body weight gain for 10 days were 109 which was equivalent to 0.83% of phenylalanine and 56 mg/chick/day, respectively, and tyrosine could supply 49% of phenylalanine.
When phenylalanine was limiting amino acid in the diet, phenylalanine did not accumulate in the plasma of 17-day-old chicks. However, it accumulated in a linear manner when the consumption of phenylalanine was moderately in excess of that re-quired to maximize growth. The calculated requirement levels were 84 and 45mg/chick/ day, respectively, when the diet contained 0 and 0.63% tyrosine.
The recovery % of ¹⁴C in respiratory CO₂ was less than 0.4% of injected dose of DL-phenylalanine-2-¹⁴C when phenylalanine consumption was less than 30.0mg and 12.0mg with or without tyrosine in the diet. It increased in a stepwise manner with increasing of phenylalanine consumption. It was concluded that the oxidation technique does not provide a means for estimating the dietary phenylalanine requirement for a maximum growth rate in the 17-day-old chick, since there was no relation between the level from which recovery % of ¹⁴C increased and the level required for maximal growth.

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1. Polyglutamic acid (PGA) produced by Bacillus subtilis No. 5 E was isolated by the precipitation with alcohol (recovery; 80%), and purified as Na-PGA (Na salt of PGA) and H-PGA (acid form of PGA) to the purities above 99%.
2. The purified PGA was found to be composed of both D and L-glutamic acids, and the D/L ratio of glutamic acids was 60:40. The ratio was not varied even when the concentration of manganese ion and other components of the media were changed.
3. The PGA was presumed as γ-PGA based on the negative results for both ninhydrin and biuret reactions.

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Specific hydrodynamic properties of γ-PGA produced by Bacillus subtilis No. 5 E were extensively investigated, and the mechanism of producing the high viscous properties of the polymer was also discussed.
1. The viscosity of the aqueous solution of PGA showed its maximum value at near neutal pH and decreased largely in both acidic and alkaline media.
The viscosity was also sharply decreased by heating the solution or by the addition of inorganic salts in the solution.
2. The intrinsic viscosity of PGA was found to be 151.
3. From the results of viscosity measurement, IR spectroscopy and ORD measure-ments, it was most likely that the PGA took parallel β-form in acidic solution, random form at near neutral pH and more contracted random form in alkaline solution which might account for the sharp decrease of viscosity with alkalinity.
4. The mean molecular weight of PGA was estimated to be 1.16×10⁶ based on the results of intrinsic viscosity and sedimentation constants. The value of 1.01X10⁶ was obtained by combining viscometric data and the length of the molecule deduced from flow birefringent measurements which was about 8000 Å. The dimension of the PGA estimated from electron microscopic measurement was 50 Å in width and 6000_??_10, 000 Å in length, respectively.

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Honeybees were breeded in a cage which was so designed as to prevent admixture with the nectar and pollen in the fields, and were fed exclusively upon 40% sucrose solution.
Enzymic reaction on sucrose was carried out with the invertase extracted from the honey which was produced by the caged bees. The resulting trisaccharide was isolated for examination and was found to be erlose.
The extracted invertase was an α-glucosidase with maltase activity and indicated the activity of transglucosidase.
Erlose is formed presumably by transglucosidation with invertase of bees in which the α-D-glucosyl group of one sucrose is transferred to the fourth carbon in glucose moiety of other sucrose.
The optimum conditions of enzyme for the transferring action were: pH, 6.0; temperature, 30°C; and sucrose concentration, 0.25M.
Hydrolysis of sucrose and formation of erlose by honeybees took place mostly in earier period (within 6 hr) of honey formation, and no substantial changes in sugar contents were observed in the ripening period (after 24 hr).

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The decomposition of glutathione (GSH) in oxygen free aqueous solution was investigated.
The rate of decomposition of GSH was of pseudo first order and depended on pH and the initial concentration. The solution was most stable at pH ranges of 5.0_??_7.5 and its pH-profile showed a curve which was often observed in hydrolysis reactions catalysed by H⁺ or OH^-. The rate constant was increased with the increase of initial concentration of GSH. This suggests the molar inter-relation of GSH. The reducing power of the solution decreased very slightly and only a trace of H₂S was formed during storage at pH 4.0_??_7.5. These indicated the stability of the SH residue.
From the analysis of decomposition products by paper and gas chromatographies and infra-red spectra, it was concluded that GSH in oxygen free aqueous solution decomposed directly into two portions, pyroglutamic acid (PGA) and cysteinyl-glycine. Glutamic acid was not detected by gas chromatography and the experimental data showed a quantitative relation between decomposed GSH and PGA formed.

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Sulfur-containing amino acid derivatives-S-alkyl-L-cysteines, S-alkyl-2-methyl-DL-cysteines and their hydantoin derivatives, and sulfoxides of these compounds--were prepared. Effects of added compounds on radiation inactivation of Escherichia coli NIHJ were tested in a 20mm solution in water or buffer.
1. In water, S-allyl compounds were more effective than S-propyl compounds for protection, and sulfoxide derivatives were less effective than sulfides. The replacement of α-hydrogen of S-substituted cysteines by methyl group decreased the protective effects. On the other hand, their hydantoin derivatives increased the effects. As it was expected from the relation between structure and protective activity, 5-allylthiomethyl-hydantoin (a hydantoin derivative of S-allyl-cysteine) was the most effective for protection and its effect was greater than that of L-cysteine.
2. In a phosphate buffer solution (1/15M, pH 6.8), protective effect of L-cysteine was the greatest, and no other compounds prepared were compared favorably with it.
The protective effect of 5-allylthiomethyl- and 5-propylthiomethyl-hydantions were greater than other compounds, but the relations which were found in water were not clear in buffer solutions. It was also found that a sulfoxide derivative of L-5-propyl-thiomethyl-hydantoin had a toxic property in a buffer solution.
3. 4-Ethylthio-DL-isovaline, 2-methyl-5-methylthio-DL-norvaline, 2-methyl-5-ethylthio-DL-norvaline, S-octyl-2-methyl-DL-cysteine and S-lauryl-2-methyl-DL-cysteine were prepared, but they didn't have biologically remarkable effects.

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The selective alkylation of ethyl 3-oxoglutarate in the presence of sodium ethoxide and magnesium ethoxide as basic catalysts has been studied. Mono-alkyl derivatives, ethyl 2-alkyl-3-oxoglutarate, were obtained in good yield by the use of magnesium ethoxide.
On the other hand, the alkylation of ethyl 3-oxoglutarate over sodium ethoxide afforded the corresponding di- and tri-alkyl derivatives, ethyl 2, 4-dialkyl-3-oxoglutarate and ethyl 2, 2, 4-tri-alkyl-3-oxoglutarate, respectively.

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In the previous report, it was evidenced that the analysis of sterigmatocystin, one of mycotoxins, was possible by gas-liquid chromatography. In this report, the extraction and clean-up method in the case of analysis of sterigmatocystin in rice by gas-liquid chromatography was examined.
Sterigmatocystin was extracted from ground rice with ethyl acetate and the ethyl acetate extract containing sterigmatocystin was evaporated to near dryness. The dry residue was dissolved in methanol-20% potassium chloride solution (4:1 v/v) and lipids were removed by extraction with hexane.
The 80% methanol solution was adjusted to a 50% methanol concentration with water. Sterigmatocystin was extracted from the methanol phase with chloroform and the chloroform extract was evaporated. The dry residue was then dissolved in acetone and added to Sephadex LH-20 column (8×500mm). Acetone was then added to the column and the eluate containing sterigmatocystin was collected and evaporated to near dryness. The dry residue was dissolved again in acetone and used for gas-liquid chromatography. By this procedure, the minimum detection quantity of sterigmatocystin in rough rice was 0.05ppm.

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We had already reported that the esters of p-hydroxybenzoic acid, a kind of antiseptics for foodstuff, induced the premature lysis of phage-infected Lactobacillus casei during the whole of the latent period. Consecutively, systematic investigations were achieved with the effect of antiseptics for foodstuff on the lysis of phage-infected cells, using nine antiseptics and a system of L. casei S-1 and phage J 1.
When high concentrations of hydrogen peroxide (100mM or more) was added at the early stage of latent period, the induction of premature lysis after the lag of about 40min was observed. Whereas, the other 8 antiseptics did not induce the premature lysis even at high concentrations.
When benzoate, salicylate, dehydroacetate, 2-(2-furyl)-3-(5-nitro-2-furyl) acrylamide, hydrogen peroxide, β-propiolactone or diethylpyrocarbonate was added at the later stage of the latent period, premature lysis was induced. The range of concentrations and the earliest time of addition for the induction of premature lysis differed with each antiseptic. Whereas, sorbate and propionate did not induce the premature lysis even when they were added several min before the onset of lysis.

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Some changes on the character of stored chicken egg yolk at 30°C were discussed by determining the amounts of the lipids and phosphorus compounds, both of which were extracted from the yolk by ether, ethanol or acetone. The results are summerized as follows.
1. Shaking conditions of the fresh and stored yolk with ether did not influence on the amounts of ether soluble lipids.
2. The amounts of ether soluble lipids and phosphorus compounds in the yolk were almost constant even after the different periods of storage and days of extraction.
3. The amounts of ether soluble phosphorus compounds of stored yolk is less than that of fresh yolk.
4. The amounts of ethanol soluble lipids of fresh yolk increases as day of extraction becomes longer.
5. The amounts of ethanol or acetone soluble lipids in stored yolk is more than that in fresh yolk.

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Steryl glycoside was isolated and purified from alfalfa leaves to be analyzed for constituent sterol and sugar. The major component sterols were β-sitosterol as well as stigmasterol and the component sugar was only glucose, suggesting that the typical molecular species of steryl glycoside in alfalfa leaves are β-sitosteryl glucoside and stigmasteryl glucoside.

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