To clarify the influence upon taste of the sugar position in the aglycone of dihydrochalcone (DHC), new nine DHCglycosides were synthesized : naringin DHC 4-O-β-D-glucopyranoside (I), naringin DHC 4-O-β-D-galactopyranoside (II), naringin DHC 4-O-β-D-xylopyranoside (III), 3, 2', 3'-trihydroxy-4-methoxy DHC 3'-O-β-D-galactopyranoside (XII), 3, 2', 4'-trihydroxy-4-methoxy DHC 4'-O-β-galactopyranoside (XIII), 3, 2', 5'-trihydroxy-4-methoxy DHC 5'-O-β-D-galactopyranoside (XIV), 3, 2', 6'-trihydroxy-4-methoxy DHC 6'-O-β-D-glactopyranoside (XV), 3, 2', 4', 6'-tetrahydroxy-4-methoxy DHC 2'4'-O-β-digalactopyranoside (XVI) and 3, 2', 4'-trihydroxy-4-methoxy DHC 4'-O-[2-O-α-L-quinovopyranosyl-β-D-glucopyranoside] (XL).Such compounds as I, II and III which carry the sugars in both the A and B rings of the DHC's were completely tasteless. Between XII, XIII, XIV, XV, XVI and XL, XIII and XL were 140 and 400 times sweeter than sucrose and the remainder were either slightly sweet, tasteless or bitter.

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A simple method based on regioselective two-step alkylation of easily-available diethyl 3-oxoglutarate (2) is described for the synthesis of racemates of the lactonic pheromones, la, lb, and 1c. Their (+)-enantiomers were also synthesized by means of microbiological reduction of the intermediary keto acids.

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A novel optical activity of lutein was studied in dodecyltrimethylammonium bromide (DTAB) solution by the measurement of circular dichroism and absorbance. The surfactant was found to bring about the circular dichroism activity of the lutein below the critical micelle concentration (CMC) in a different way from that by sodium dodecyl sulfate (SDS). This phenomenon was interpreted by the card-pack model of the lutein aggregate in which lutein molecule was slightly shifted each other. The above optical activity abruptly becamestrong just before the CMC of DTAB.This seems to correspond to the transition from the polymeric aggregate of the lutein to the oligomeric one. Such an optical activity disappeared beyond the CMC on the incorporation of the lutein molecules into the surfactant micelles. The molar binding ratios of DTAB to the lutein were determined to be 130 to 210 on the basis of the lutein concentration dependence of the DTAB concentration showing the arbitrary ellipticity. These ratios were clearly larger than those for SDS. On the other hand, filtration measurement showed that the size of the lutein-DTAB complex was larger than 2 μm in diameter. These phenomenawere discussed assuming the possible model of the aggregate as a comparative study of the anionic and cationic surfactants causing the novel optical activity of this aggregate.

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A gram positive bacterium (strain No. 109) isolated from soil as a producer of cyclodextrinase was identified as Bacillus coagulans. The cyclodextrinase from B. coagulans was purified to a homogeneous state by disc-electrophoresis after Streptomycin treatment, DEAE-Sephadex column chromatography, Ultrogel AcA44gel filtration and hydroxyapatite column chromatography.The molecular weight of the enzymewas determined to be 6.2 × 10₄ by sodium dodecylsulfate gel electrophoresis. The isoelectric point of the enzymewas pH5.0. The enzymewas most active at pH 6.2 and 50°C, and stable up to 45°C at pH 7.0 and in the range of pH 6.0-7.3 at 40°C on 2 hr incubation. This enzyme hydrolyzed linear maltooligosaccharides (such as maltotetraose (G4), maltopentaose (G5) and maltohexaose (G6)) and α-, β- and γ-cyclodextrins (CDs) faster than maltotriose (G3) and short chain amylose (DP 18), but did not hydrolyze maltose. The rates of hydrolysis for polysaccharides (such as starch, amylose and amylopectin) were below 1 %as compared to that for β-CD. The Kmvalues for G3, G4, G5, G6, shortchainamylose(DP 18) and α-, β-and-γ-CD were4.5, 4.0, 2.3, 1.5, 1.5, 10, 2.8 and0.47 mil, respectively. The products with this enzymehad the α-configulation.

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Fermentative production of 3aα-H-4α-(3'-propionic acid)-5a-hydroxy-7αβ-methylhexahydro-1-indanone-d-lactone (HIL) from soybean sterol was studied in order to use it as an intermediate for chemical synthesis of 19-norsteroids. A mutant of Nocardia corallina converted 20 g/liter of soybean sterol into 2.8 g/liter of HIL with a 25% yield on a molar basis.The dominant factors improving the productivity were the use of an amino acid mixture as a nitrogen source and the preparation of the sterol suspension by sonication or with surfaceactive agents.

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β-1, 3-Glucanase (EC 3.2.1.39) is one of the major soluble proteins of cultured tobacco cells but not of leaf tissues. The enzyme activity in cultured cells increased with culture age, physical and chemical properties of this enzymewere characterized. The enzymecontained about 1 %carbohydrate consisting of only arabinose residue. Its isoelectric point was at pH 9.9.The amino acid composition indicated relatively low content of polar amino acids. The molecular weight of the enzyme estimated by sedimentation equilibrium and sodium dodecyl sulfate gel electrophoresis was 32, 000 and 33, 000, respectively, indicating that the enzyme consists of a single polypeptide chain.

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Compounds in which an aryl or heteroaryl ring is linked to the ortho position of a benzoic acid moiety by a bridging group of up to four atoms are shown to inhibit the gravitropic response of cress seedling roots between 10^-5 and 10^-8 M. No significant difference in inhibitory activity is observed between compoundscontaining up to four saturated or two partially unsaturated bridging atoms, although analogues containing three or four partially unsaturated bridging atoms are one to two orders of magnitude moreactive. Compoundsin which the aryl nuclei are fused together are shown to be inactive at the highest concentration tested. The results have been interpreted in terms of the aryl groups in the molecule interacting with a hypothetical receptor site, with the bridging atoms acting as a more or less flexible coupling to facilitate such interaction.

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The conformation and some properties of bovine α_s2-group-casein (a mixture of α_s2-, α_s3- and α_s4-casein) were investigated. The secondary structure was estimated from Moffitt parameters and circular dichroism spectra in the ultraviolet region. α_s2-Group-casein contained about 20% of α-helix and a small amount of β-form. The higher content of α-helix in α_s2-group-casein than in α_s1-casein is considered to be due to the lower content of proline. It is shown that heat treatment at 90°C for 15 min caused about 35 %destruction of the α-helix. It is also shownby charge shift electrophoresis that α_s2-group-casein has an amphiphilic structure.

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When soybean lyophilized 1IS globulin was stored at RH96%and 50°C, the redispersibility of the protein as measured over a 1 hr period drastically decreased after 4 hr. Whenthe redispersing time was prolonged to 24 hr, US globulins stored for up to 12 hr redispersed similarly to the control, but became insoluble after 24 hr of storage. A gel filtration study showed that the stored 1 IS globulin had already polymerized mainly through disulfide bonds after 12 hr of storage.
Scanning electron microscopic observation showedthat a globular structure of the control USglobulin changed to an aggregated structure during storage. Polymerized subuiiits linked with disulfide bridges were observed using gel filtration in a sodium dodecyl sulfate (SDS) solution and SDSpolyacrylamide gel electrophoresis and the number of the polymerized subunits increased during storage. The I IS globulin, however, did not polymerize with humidity as much as in heat denaturation at 100°C (ionic strength 0.5, protein concentration 0.5 %).

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The trypsin inhibitors in buckwheat seeds were isolated by affinity chromatography on trypsin-Sepharose 4B, and the components were fractionated by chromatography on DEAESepharose CL-6B. The major components, inhibitors I, II and III, were found to be homogeneous proteins with molecular weight of about 8, 000. Trypsin inhibitory activity was more pronounced than the chymotrypsin inhibitory activity in all the inhibitor preparation obtained.The three major inhibitors had similar amino acid compositions and had no detectable amounts of tryptophan and carbohydrate. A high level of acidic and basic amino acid residues and a low level of methionine, tyrosine and phenylalanine residues characterized the inhibitors.Although the inhibitors I and II were particularly thermostable, inhibitorIII, the most abundant component, was shown to be relatively heat-labile.

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Basic flavor components were isolated from various types of miso and determined qualitatively and quantitatively by gas chromatogiaphy and mass spectrometry. 12 pyrazines, 3 pyridines, N-methylpyrrolidone, 2-acethylpyrrole and benzothiazole were identified. All but tetramethylpyrazine had not been reported previously for their presence in miso. Concentrations of the basic components, except for pyridines, varied considerably, depending on the type of miso. The factors which influenced the levels of these componentswere primarily a soy bean cooking condition and a koji ratio. The flavor contribution of alkylpyrazines to each type ofmiso is also discussed on the basis of the additivity of odorous mixture. Alkylpyrazines were judged to contribute to miso flavor, particularly in the soy bean miso.

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Heat evolution during the microbial degradation of different carbon sources in soil was calorimetrically studied with a multiplex heat-conduction calorimeter over the incubation temperature range of 295.2 to 320.9 K. Different thermograms were obtained with the degradation of D-glucose, D-fructose, D-galactose, D-mannose, sucrose or lactose as a limited energysource.While the shapes of the thermograms changed with changing of the incubation temperature, the total amount of heat evolved during the degradation of carbon sources in soil was unchanged in the temperature range of 303.6 to 320.9 K. This observation was commonfor all the experiments with the different sugars. The total amount of heat evolved observed in this temperature range was in the range of 14 to 15 kJ (g of sugar)^-1. From the earlier phase of the thermogram where the heat evolution rate increased exponentially, the degradation rate constant was determined. Applying the Arrhenius equation to the system, apparent activation energies were obtained. The values obtained with the six different carbon sources were in the range of 64 to 92 kJ mol^-1. The apparent Gibbs energy of activation was determined to interpret the
microbial activity for the degradation of each sugar and the degradation activity for the sugars in soil was found to be in the following order at 298.15 K; D-glucose>sucrose>lactose>dfructose > D-galactose > D-mannose.

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Two kinds of N-acetylmuramidase, M-l and M-2 enzymes, that were isolated from the cultural broth of Stm. globisporus 1829, were remarkably different in amino acid composition, immunological properties and modes of lytic action from each other. The M-l enzyme was composed of 186 amino acid residues of which two moles were of half cystine, while the M-2 enzyme was composedof 99 amino acid residues with no cysteine. The hydrolyzing action of the M-2 enzyme was suppressed by the presence of an N-acetyl group on muramic acid residues in the peptidoglycan moiety, while that of the M-l enzyme was independent of the presence of N-acetyl groups. However, the hydrolyzing activity of both enzymes was enhanced when some muramicacid residues were substituted with stem peptides containing alanine, isoglutamine and lysine.

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The formaldehyde dehydrogenase (EC 1.2.1.1) from the yeast Pichia pastoris IFP 206 was purified to homogeneity. The enzyme had a molecular weight of 84, 000 daltons and was composed of two identical subunits of a molecular weight of 39, 000 daltons. The N-terminal end of the subunits is blocked. The protein showed 6, 3 free -SH groups per mole and 12, 5 in the presence of NAD⁺.Enzyme stability was increased by addition of glycerol during the purification.
The enzyme activity is NAD⁺ and glutathione dependent. The reaction product is Sformylglutathione.The presence of an £-formylglutathione hydrolase (EC 3.1.2.12) in the cell free extract was detected. The formaldehyde dehydrogenase showed an optimum pH of 7.9 and an optimum temperature of 47°C. The activation energy was 3.2 kcal/mol. The Michaelis constants for NAD⁺and S-hydroxymethyl glutathione were respectively 0.24 mMand 0.26 mM.

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Changes in calcium activated protease activity in rat skeletal muscle during fasting were studied. Cathepsin D activity in the same muscle was also measured. Calcium activated protease activity was significantly increased in the longissimus muscle of the back and the hind limb muscle during fasting. The increase in Cathepsin D activity was not as high as that of calcium activated protease. Calcium activated protease is generally supposed to degrade myofibrillar protein before the lysosomal enzymes (such as Cathepsin D) act in protein degradation due to fasting. It was indicated that calcium activated protease might take a significant role in enhancing the protein degradation resulting from fasting.

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Changes of the folate-binding protein (FBP) concentration in bovine milk after parturition were investigated. The FBP was highly purified from mature milk by affinity chromatography.The purified FBP showed a single protein band in polyacrylamide gel electrophoresis and was immunologically homogenous in double immunodiffusion. However, in two-dimensional gel electrophoresis, the FBP was separated into several spots in isoelectric focusing in the first dimension, and each spot also showed two molecular weights in SDS-gel electrophoresis in the second dimension. But these FBP molecules were immunologically identical with each other. The neuraminidase treatment obviously diminished the number of isoelectric points of the FBP. Thus, the variety of FBP molecules was at least partially due to the variability of the sialic acid content in the carbohydrate moieties. Moreover, the milk FBP showed speciesspecificity among mammals immunologically as well as physicochemically.

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Anactinomycetes producing aspartate aminotransferase inhibitor was isolated from soil.This strain was identified and named Streptomyces sumanensis nov. sp. NK-23 from its taxonomical characteristics. Whenthis strain was aerobically cultured in a mediumcontaining 4% (w/w) glucose, 1.5% meat extract, 1.5% polypeptone and 0.3 % NaCl at pH 7.0, a remarkable amount of the inhibitor (designated as gostatin) was produced in the culture filtrate.

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Superoxide dismutase was easily isolated from Serratia marcescens ATCC 21074 by ammoniumsulfate fractionation and Dyematrex Gel Green A chromatography. The purified enzymewas a manganese-containing protein with a molecular weight of 4.8×10⁴. Combination of gel electrophoresis in dodecylsulfate and gel filtration showed that it was composed of two equal molecular subunits. The dimeric protein contained 1.5 g atoms of manganese and exhibited molecular extinction coefficients of 9.4×10⁴ M^-1cm^-1 at 280 nmand 8.9×10² M^-1cm^-1at 470 nm. The enzyme showed similarities with manganese superoxide dismutases from other prokaryotes.

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1-Deoxy-D-altro-heptulose phosphate (DAHP) synthase activity was found in the cell-free extract of a transketolase mutant, BG2532, of Bacillus pumilus IFO 12089. The enzyme was partially purified by protamine sulfate treatment, ammoniumsulfate fractionation, DEAEcellulose and hydroxylapatite column chromatography. When DL-acetoin and D-ribose 5-phosphate were incubated with the partially purified enzyme preparation, DAHP and acetaldehyde were detected as reaction products. Thiamine pyrophosphate (TPP) and Mg²⁺ were required as co factors. The results of the stoichiometric measurementsindicate that DAHPsynthesis proceeds according to the following formula :
TPP5Mg²⁺
DL-Acetoin+D-Ribose 5-phosphate → Acetaldehyde+DAHP
Intracellular DAHP formed by this reaction may be excreted and accumulated in culture broth as 1-deoxy-D-altro-heptulose after dephosphorylation.

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Sixty six 2, 3-dicyano-5-substituted pyrazines were synthesized and their herbicidal activities against barnyard grass were measured in pot tests to clarify the relationship between chemical structure and activity. The activity of 59 derivatives was related parabolically to the hydrophobic substituent parameter at the 5-position of the pyrazine ring.

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Sixty-eight 6-substituted 5-ethylamino and 5-propylamino-2, 3-dicyanopyrazines were synthesized and their herbicidal activities against barnyard grass were measured in pot tests.The most active compound was 2, 3-dicyano-5-propylamino-6-(m-chloro phenyl) pyrazine.The activities of the two series of compoundswere analyzed quantitatively using the hydrophobic and steric parameters of substituents at the 6-position of the pyrazine ring and an indicator variable.

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A mutant, No. 1-231, resistant to S-P-aminoethyty-L-cysteine (AEC) plus threonine which was previously derived from a low citrate synthase mutant (No. 1 5-8) of Brevibacterium flavum, produced 41 g/liter of lysine (as HC1 salt, 41 %yield) and showed pyruvate kinase and homoserine dehydrogenase activities of about 1/10 and 1/20 as much as those of No. 15-8, respectively, but its aspartokinase was still normally sensitive to the feedback inhibition by lysine plus threonine. Another AEC-resistant mutant, No. 2-190, from No. 15-8 showed aspartokinase insensitive to the feedback inhibition without any change in pyruvate kinase and homoserine dehydrogenase activities. In addition, both the two AEC-resistant mutants and parent No. 1 5-8 showedpartial desensitization of phosphoenolpyruvate carboxylase to the feedback inhibition by L-aspartic acid.
β-Fluoropyruvic acid-sensitive mutants No. 22 and No. 2-1 1 were derived from No. 1-231.These sensitive strains produced 51 g/liter of lysine (51 %yield) and were found to be completely defective in homoserine dehydrogenase activity.
It was concluded from the results that depression of pyruvate kinase activity leads to an increase in lysine production.

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The antioxidative effects of dietary a-tocopherol (TOC) and riboftavin-tetrabutyrate (RTB) against tissue lipoperoxidation caused by the long-term administration of methyl linoleate hydroperoxide (HPO) to rats were investigated by measuring the spontaneous chemiluminescence (CL) intensities and thiobarbituric acid (TBA) reactants of the liver, lung and heart.
TOC supplementation resulted in the effective decrease of CLintensities and TBAreactants in the three organs, while RTBsupplementation led to the definitive decay of both indices of the lung and a significant decrease in the CL intensity of the heart, as compared with those of rats dosed with HPOand not given any supplemental antioxidant.
Although the activities of glutathione peroxidase and glutathione reductase in the three organs obtained from rats dosed with HPOfor 29 days were clearly lower than those of the control rats, both enzyme activities in rats dosed with antioxidants other than HPOwere generally maintained at levels almost equal to those of the control rats. Glutathione peroxidase of the liver and heart and glutathione reductase of the liver were shownto be further activated by the simultaneous supplementation of TOC and RTB.
The results indicated that both TOC and RTB effectively act as antioxidants in rats dosed with HPOover a long-term. Oneof the antioxidative actions of both agents is ascribed to protection of the glutathione peroxidase system in organs undergoing lipoperoxidation caused by the long-term treatment of dietary hydroperoxides.

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The inhibitory effect of various compoundson insect cuticle formation was investigated using the cultured larval integument of rice stem borer, Chilo suppressalis Walker. The effect of 2, 6-difluoro- and 2, 6-dichloro-benzoyl-4-chlorophenylurea was very high, the concentrations required to suppress the new articular growth to 50% of the control (I₅₀) being 0.083 and 0.58μm, respectively. The I₅₀ values for 2, 4-dinitro- and pentachloro-phenol and other uncouplers were observed over the range of 2.6-115μM. Some N-(2', 4'-dinitrophenyl)-glucosamine derivatives, which were designed as substrate analogs of chitin biosynthesis, inhibited this new cuticle development. The most effective glucosamine derivative was methyl 2, 6-di-(2', 4'-dinitroanilino)-2, 6-dideoxy-a-D-glucopyranoside (I₅₀ = 1.58μm). Protein synthesis inhibitors such as cycloheximide and puromycin were quite potent with an I₅₀ value of 2.0 and 6.3μJM, respectively.The present system was shownto be very sensitive as a bioassay procedure for potential insect growth regulators.

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During the storage of cassava roots, coumarins and phenols were produced and the activities of phenylalanine ammonia-lyase and peroxidase were activated in every part of the parenchymatous tissue, that is the outermost tissue (called the A-part), the intervening tissue (called the B-part) and the innermost tissue (called the C-part), in parallel with the occurrence of physiological deterioration in the B-part. In manycases, secondary metabolites were produced more strongly in the B-part than in the A- and C-parts. Parenchymatous tissue blocks were divided into the A-, B- and C-parts and they were separately incubated, together with undivided parenchymatous tissue blocks. In both cases, metabolic changes occurred in the A-, B- and Cparts, and physiological deterioration was induced only in the B-part.

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A new antimetabolite, nourseimycin, an antagonist of L-proline, was isolated from the fermentation broth of a strain of Streptomyces noursei. Nourseimycin, C₉H₁₅N₃O₆•2H₂O, is a dipeptide which contains L-alanine and an unknown amino acid. Its antimicrobial activity in the minimal mediumwas weakened by the addition of L-proline. Some amino acids and peptides also weakenedits antimicrobial activity.

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Crystalline aromatic L-aminoacid decarboxylase from Micrococcus percitreus is inactive in the absence of pyridoxal phosphate (PLP). The inactive form of the enzyme shows absorption at 340 nmand contains one mol of PLPper mol of enzyme. Binding of PLP to the inactive form is accompanied by a pronounced increase in absorbance at 415 nm. The amountof PLP that binds to this holoenzyme is 2 mol per mol of enzyme. The inactive half-resolved form, i. e. semiapoenzyme, is obtained again by dialysis of the holoenzyme against phosphate buffer.When the semiapoenzyme is dialyzed against phosphate buffer containing 3, 4-dihydroxyphenyl-L-alanine, it loses the absorption at 340 nm with the loss of PLP. This apoenzyme regains the activity and absorption at 340 nm and 415 nm on association with PLP.

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The metabolic pathway of aniline was examined in Rhodococcus erythropolis AN-13 that was isolated from soil when aniline was provided as a sole source of carbon and nitrogen. cis, cis-Muconic acid and /Mtetoadipic acid were detected by thin-layer chromatography in an incubation mixture containing aniline and resting cells of this strain. These two carboxylic acids were also formed from cateehol, when the substrate was incubated with cell-free extract of aniline-grown cells, and characterized spectrally as crystalline samples. Ammoniawas released from aniline by resting cells. The cell-free extract of aniline-grown cells had a strong catechol 1, 2-dioxygenase activity. Catechol, once formed from aniline, was apparently converted so rapidly to cis, cis-muconic acid that it could not be isolated. These results suggest that R.erythropolis AN-13 converted aniline to catechol with the release of ammonia and then mineralized catechol ultimately to inorganic end products, H₂O and CO₂, through the β-ketoadipic acid pathway.

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Three Epstein-Barr virus activating principles have been isolated from the leaves of Sapium sebiferum (Euphorbiaceae), which is one of commonroadside and garden trees in Japan. By chemical and spectroscopic evidence they were identified as tigliane type diterpeneesters with the structures of 1, 2 and 3. 1 and 2 strongly induced an early antigen of the virus in a Raji cell, while 3 did so weakly. The activity of some derivatives of 2 are also discussed.

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