In the case of fermentative production of adenosine by the mutants derived from a Bacillus strain, abnormal fermentations due to the instability of mutants were frequently observed, and therefore studies were performed on the stabilization of mutants.
Among the genetic characteristics of adenosine-producing mutants, the xanthine-requirement was the most important factor and the adenosine productivity was found to decrease significantly as the number of revertants on this genetic marker increased. By using the media supplemented with excess amount of guanine sources, the increase of xanthine-nonrequiring revertants both during the transfers on slants and in the preservation periods was perfectly suppressed. Secondly, an attempt was made to derive mutants in which no revertants would appear. Such mutants (‘NB-strains’) were selected by using a medium on which revertants appeared in a high frequency. One strain of the above mutants was found defective in XMP aminase.

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The sugar moiety of isonaringin (I) was confirmed as rutinose using _NMR spectral data. Furthermore, the apigenin-7-rhamnoglueoside (IV), derived from compound I was successfully converted to linarin by partial methylation with dimethyl sulfate, indicating that compound IV has the structure of apigenin-7-β-rutinoside. Thus, compound I was identical with narirutin.
The optical rotatory dispersions of narirutin, didymin and neoeriocitrin were measured. The former two compounds have the aglycones of 2 (S) configuration, and in the latter aglycone is racemized.
The, so called, lonicerin distributed in citrus plants was proven to be identical with veronicastroside.

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The flow of the mixture of methylcellulose (MC)-sucrose-citric acid-water was essentially thixotropic. The viscometric behaviors could be expressed by the power law, S=KDⁿ, where S was shearing stress and D rate of shear. The differential viscosity (ηd) of the mixture was strongly dropped by the addition of citric acid. Sucrose had the tendency to increase ηd of the mixtures except in the case of high sucrose concentration. From the results obtained, it has been concluded that citric acid tends to break the intermolecular hydrogen bonds of MC molecules, and that sucrose tends to keep the hydrogen bonds.

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Acid carboxypeptidase II from Aspergillas oryzae was purified from the rivanol nonprecipitated fraction. The purified enzyme was homogeneous on polyacrylamide gel disc electrophoresis. The optimum activity of the enzyme lay at pH 3.0 for carbobenzoxy-L-glutamyl-L-tyrosine. The enzyme was inhibited by diisopropylphosphorofluoridate and SH reagents such as p-chloromercuribenzoate and monoiodoacetate, but not by such metal chelating agents as ethylenediaminetetraacetate, α, α'-dipyridyl and o-phenanthroline. The molecular weight of the enzyme was estimated to be about 105, 000.

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Acid carboxypeptidase III from Aspergillus oryzae was purified from the rivanol nonprecipitated fraction. The optimum activity of the enzyme occurred at pH 3.0 for carbobenzoxy-L-glutamyl-L-tyrosine. The enzyme was inhibited by diisopropylphosphorofluoridate and SH reagents such as p-chloromercuribenzoate and monoiodoacetate, but not by such metal chelating agents as ethylenediaminetetraacetate, α, α'-dipyridyl and o-phenanthroline. The molecular weight of the enzyme was estimated to be about 61, 000. The enzyme hydrolyzed the peptides that possess masked or bulky N-terminal.

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From root extracts of Phryma leptostachya L. was isolated a new lignan. Its structure has been determined to be 1-ace toxy-2-(3, 4-methylenedioxy) phenoxy-6-(2-methoxy-4, 5-methylenedioxy) phenyl-3, 7-dioxabicyclo [3. 3. 0] octane on the basis of the chemical properties and spectra of its degradation products.

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The mass spectra of phrymarolins, which were isolated from Phrpma leptostachya L. as novel lignans, have been investigated. The most predominant fragmentation was the splitting of the acetal linkage. The fragment ions (m) and (n), at m/e 141 and m/e 99 respectively, are considered to be characteristic to the lignans. The accurate molecular weight measurements of important ions provided a further evidence for the structure of phrymarolin-I.

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Porcine myoglobin was isolated by fractionation with ammonium sulfate and crystallized with 3.8 M phosphate buffer.
Chromatography of the porcine crystalline myoglobin on a molecular-sieve column gave a single elution band, which agreed well with that of horse myoglobin.
By ultracentrifugal analysis, the sedimentation constant (s_{20, w}) was found to be 1.96 S.
The iron content of the myoglobin was 0.324%. This value corresponds to the minimal molecular weight of 17, 200.
Absorption curves and millimolar extinction coefficients of the porcine myoglobin in several derivatives, namely, reduced (RMb), met (MMb), carboxy (MbCO) and cyanment (MMbCN) forms were examined in the visible region. The spectral characteristics of the por-cine myoglobin derivatives were in good agreement with those of horse myoglobin,
Three components were detected for the porcine myoglobin by starch gel electrophoresis, and each of them had higher migration velocity than those of horse myoglobin.

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Improved inosine producers were found with a high frequency among the mutants resistant to a low concentration of 8-azaguanine derived from AMP deaminase negative adenine auxotrophs of Bacillus subtilis K strain. The best mutant accumulated 16_??_18g/liter of inosine, 60-80% higher than the parent. PRPP^* amidotransferase and succino-AMP lyase of all of the improved inosine producers tested were not repressed by adenosine but still repressed by guanosine. Adenine permeability was suggested to be also altered in some of the mutants which produced inosine even in the presence of a high concentration of adenine. Adenine prototrophic revertants from all of the mutants tested accumulated a small amount of adenosine but not inosine.

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A mutant strain HA-2 was derived from an adenine-requiring mutant of Bacillus subtilis IAM 1145 by transduction with bacteriophage SP-10 and subsequent N-methyl-N'-nitro-N-nitrosoguanidine treatment. The strain could convert exogenously supplemented hypoxanthine or inosine to succinyladenine, succinyladenosine and succinyladenosine 5'-monophosphate (succinyl AMP), and accumulate these compounds in the culture fluid. The strain, however, failed to convert exogenously supplemented inosine 5'-monophosphate to these succinyl compounds. The yields of succinyladenine, succinyladenosine and succinyl-AMP in a production medium supplemented with 17mM of hypoxanthine were about 4.4mM, 5.2mM and 2.2mM, respectively, after 4 days growth.

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By successive mutagenic treatments including transduction with bacteriophage SP-10, ultraviolet light irradiation and N-methyl-N'-nitro-N-nitrosoguanidine treatments, a mutant, strain No. 322, capable of converting exogenously supplemented hypoxanthine or inosine to guanine and guanosine, was derived from an adenine-less, IMP-producing mutant of Bacillus subtilis IAM 1145. Strain No. 322 was an adenine-leaky mutant lacking GMP-reductase, adenase, and 5'-nucleotidase. The strain effectively accumulated guanine and guanosine in the culture fluid, when grown in the presence of hypoxanthine or inosine, while it failed to convert exogenously supplemented IMP to the guanine derivatives.

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The effect of the introduction of acetyl groups into cellulose on its acid saccharification was investigated. Cellulose, DS 2.87- and DS 2.36-cellulose acetates and regenerated celluloses from the acetates were saccharified at 100 and 135°C by using 0.4, 0.8 or 1.6% solutions of sulfuric acid as hydrolyzing agents. The cellulose acetates were far more readily saccharified than cellulose. The regenerated celluloses could not so readily be saccharified as the acetates. It is suggested that the ease of saccharification of cellulose acetates might be due principally to some alteration in the crystallite (micell) structure caused by the introduction of acetyl groups into cellulose molecules.

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Agar producing a firm gel with specific theological properties as well as a good commercial value was processed from Gracilaria foliifera (Forsskal) Bφrgesen, a red alga harvested along the Florida west coast. The alkali pretreatment of the seaweed based on the Funaki-Kojima's method was applied before the process of agar extraction. The chemical and physical properties of the processed agar were compared with other typical agar experimentally processed.

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Tannin acyl hydrolase (EC 3. 1. 1. 20) of Asp, oryzae No. 7 hydrolyzes tannic acid to glucose and gallic acid. The intermediate hydrolyzates are 1, 2, 3, 4, 6-pentagalloyl glucose, 2, 3, 4, 6-tetragalloyl glucose and two kinds of monogalloyl glucose.
The enzyme hydrolyzes ester compounds of gallic acid, but does not hydrolyze any other substrate analogues such as methyl-resorcyrate.
The enzyme reaction is inhibited competitively by substrate analogues which have phenolic hydroxyls with the exception that 2, 6-dihydroxy benzoic acid inhibits noncompetitively. Therefore the binding site of the enzyme may be able to react with any kind of phenolic hydroxyl, although the substrate forming a true ES-complex must be an ester compound of gallic acid.

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The quantitative determination of pipecolic acid was examined.
The reaction of 3% ninhydrin solution in n-butanol, saturated with citrate buffer (pH 4.2), with pipecolic acid in boiling water for 3 min yielded the colored products showing _??_max at 570mμ, but with proline hardly yielded those products. By the colorimetry proposed, it is possible to determine the amount of pipecolic acid in the sample containing proline no more than 50 times the amount of the pipecolic acid, directly from the calibration curve using pipecolic acid.
The method for removal of amino acids from the sample containing pipecolic acid and proline was examined and discussed.

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5-Carboxyuracil derivatives were shown to react with aqueous sodium bisulfite in mild condition resulting in facile decarboxylation to give corresponding 5-decarboxy-5, 6-dihydrouracil-6-sulfonates and uracils in good yield. The former compounds were quantitatively transformed to the latter in alkaline condition. Mechanistic feature of this reaction was discussed, which implied the initial nucleophilic addition of bisulfite across the 5, 6-double bond. 5-Carboxycytosine was also shown to react similarly, however, accompanied by hydrolytic deamination.

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The coupling reaction of glucoamylase and halogenacetyl cellulose (HAC) without pretreating with organic solvent led to form large particles of immobilized glucoamylase and the activity and the specific activity of the preparation were very low. However, the Coupling reaction with HAC pretreated with organic solvents allowed to form very fine particles and the activity was increased by five times. The latter contained 3_??_6% of enzyme protein and the specific activity to maltose reached to 80_??_90% of native glucoamylase. Since the specific activity of the preparation was presumed to be much influenced by the particle size, the specific activity and general properties of different particle sizes were compared with those of native enzyme. The specific activities of particles of 0_??_15μ, 15_??_55μ, 70_??_190μ and 130_??_270μ showed 82%, 33%, 27% and only 7% of native enzyme, respectively. Km values of native form, 0_??_15μ, 15_??_55μ and 70_??_190μ particles were 0.90×10^-3_M, 1.35×10^-3_M, 1.60×10^-3_M and 2.15×10^-3_M in the case of maltose as substrate, respectively. The other properties of particles of 0_??_15μ were almost identical to those of native enzyme except for the effect of temperature on the reaction rate. However, pH activity, pH stability and urea stability of particles of 70_??_190μ were much inferior to those of native enzyme and particles of 0_??_15μ.

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A plastein was synthesized with α-chymotrypsin from a dialyzable fraction of a peptic hydrolysate of soybean protein.
The plastein was obtainable also by use of an insoluble preparation of α-chymotrypsin. This may rule out the possibility that the plastein is a product resulting from some chemical peptide-protein (enzyme) aggregation.
No appreciable amount of the plastein was produced when chymotrypsinogen was used instead of α-chymotrypsin.
The plastein synthetic, as well as the protein hydrolytic, activity of α-chymotrypsin was inhibited more or less by a hydrophobic inhibitor (n-hexane), a competitive inhibitor (benzolyl-D, L-phenylalanine), and divalent cations (Zn²⁺, Hg²⁺ and Cu²⁺); the degree of inhibition in each case was approximately similar against both the synthetic and the hydrolytic activities.
Either diisopropylphosphorylation of the β-O of Ser-195 or methylation of the 3-N of His-57 imidazole of α-chymotrypsin repressed the synthetic, as well as the hydrolytic, activity.
Based on these results a possible mechanism was discussed of the plastein synthesis by α-chymotrypsin, especially in relevance to its acylation and deacylation.

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The contribution of the system of DOPA, tyrosine and polyphenol oxidase to the remarkable increase of indophenol reducing value during the boiling procedure of the aqueous extract of potato was investigated and discussed. When the red solution of resulting DOPA-chrome by the action of polyphenol oxidase on DOPA and tyrosine at the level of potato juice was heated, the solution turned from red to colorless and simultaneously the indophenol reducing value increased remarkably. And it seems that the resulting indophenol reducing substance is a sort of reductone, 5, 6-dihydroxyindole. The system of other polyphenols gave little increase of indophenol reducing value. Therefore the system of DOPA, tryosine and polyphenol oxidase is specific to the above increase.

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Mutants resistant to α-amino-β-hydroxyvaleric acid (AHV) were derived from various bacteria which belong to Corynebacterium, Brevibacteriun, Arthrobacter Microbacterium, or Bacillus by mutational treatment with N-methyl-N'-nitro-N-nitrosoguanidine (NTG), and screened for their ability to produce L-threonine. A number of L-threonine producers were obtained from each group of bacteria. Among them, the mutants derived from C. ghuauricum KY9159 (Met^-) were further mutagenized with NTG to derive thialysine (S-Lys)-resistant mutants. An AHV-resistant mutant, KY10484 was proved to be much more sensitive to the growth inhibition by thialysine than the parent strain, KY9159. From KY10484, a number of AHV- and thialysine-resistant mutants were derived. Approximately a half of these mutants were found to produce more L-threonine than KY10484. Among these mutants, KY10440 (Met^-, AHV^R, S-Lys^R) was used to investigate the cultural conditions for L-threonine production. The growth of KY10440 decreased largely with addition of L-homoserine, a threonine precursor. L-Asparagine, L-cystine, L-glutamine Or L-arginine partially reversed the inhibitory effect of L-homoserine. Addition of these amino acids at low level led to increase L-threonine production. The amount of L-threonine accumulation reached to a level of 14mg/ml with a medium containing 10%. glucose and to a level of 10mg/ml with a medium containing 5% molasses (as glucose).
Another AHV- and thialysine-resistant mutant, KY10251 which was also derived from KY9159 was found to produce both 9mg/ml of L-threonine and 5.5 mg/ml of L-lysine in a culture broth.

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The structure-activity relationships of 3-(3', 5'-dichlorophenyl) imidazolidine-2, 4-dione derivatives were investigated by the agar dilution method using Sclerotinia sclerotiorrun as a test microbe. Several compounds were tested for antimicrobial spectrum in vitro with other pathogenic microbes and for foliage protective activity in green house tests with rice sheath blight, rice brown spot, damping-off of cucumber and kidney bean stem rot. It was found that the antimicrobial activity was enhanced when the 1-position of imidazolidine ring was substituted by an alkyl group but was reduced when the 5-position was substituted by alkyl groups. Generally, 3-(3', 5'-dichlorophenyl) imidazolidine-2, 4-dione derivatives were active against Sclerotiniaceae, Corticiaceae, Dematiaceae, Polvstigmataceae or Pleosporaceae. In green house tests, some of these compounds showed high protective activity against rice sheath blight, rice brown spot, damping-off of cucumber and kidney bean stem rot. Results of the green house tests on the above mentioned diseases correlate well with those of in vitro tests except in the case of kidney bean stem rot.

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The mixture of DL-α-alanine and D-glucose was roasted at 250° for about an hour in nitrogen atmosphere. From the volatile condensates were isolated and identified alkyl and acyl pyrroles, alkyl pyrrole-2-aldehydes, furfuryl pyrroles, alkyl pyrazines and furanic compounds. The identification of these compounds was based on the spectroscopic methods (MS, GC-MS and IR) and gas chromatographic analysis.

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