An enzymatic oxidation of kojic acid to comenic aldehyde was found in the decomposition process of kojic acid by Arthrobacter ureafaciens strain (K-l), a kojic acid decomposing bacteria.
This enzyme was (probable a new type of non-heme iron protein) is assumed to catalyze the dehydrogenation of kojic acid, while the ferric ion contained in the enzyme is considered to serve as an acceptor of hydrogen released from kojic acid. The resulted ferrous ions are oxidized either by molecular oxygen under aerobic conditions or by NAD under anaerobic conditions, accompanying hydrogen peroxide in the former and reduced NAD in the latter.
The enzyme was partially purified by using ammonium sulfate precipitation, gel filtration on Sephadex G-200 column and column chromatography with DEAE-Sephadex A-50. The activity increased to 85 fold, compared with crude extracts and the recovery of the activity was 33.9%. The optimum pH of the reaction was 7.75. The enzyme was inactivated by PCMB, and unstable upon heat treatment. A loss of about 50% of the activity was caused by heating at 35°C for 5min, but some reducing agents protected the enzyme from PCMB inhibition and the heat inactivation. Not only kojic acid, but also benzyl kojic acid or 5-methoxy kojic acid may be substrates. Km value for kojic acid was 1.43×10^-5M. The molecular weight of the enzyme was estimated to be about 55, 000 and the enzyme contained about two atoms of iron in one molecule. The reaction mechanism for kojic acid oxidase is discussed.

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The substrate specificity of Serratia protease was determined using various synthetic substrates. The enzyme did not participate in the hydrolysis of di- and tri-peptides except benzoylglycylleucinamide which was split at a limited rate into hippuric acid and leucinamide. The enzyme action on larger peptides was also studied. The enzyme cleaved the gly-leu bond in eledoisin related peptide and the gly-phe bond in bradykinin. The enzyme split oxidized insulin B-chain at twelve different peptide bonds.

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Aseptic rennet curd prepared under the aseptic conditions and Str. cremoris- and L. helveticus-cheese prepared by sandwiching the cell pellets of Str. cremoris and L. helveticus between aseptic rennet curd, respectively, were ripened at 10°C for desired period.
Water soluble nitrogen (WSN) contents of both aseptic rennet curd and two kinds of cheese were determined. Gradual increase of WSN content of aseptic rennet curd was recognized all through the ripening preiod. WSN contents of both Str. cremoris- and L. helveticus-cheese were remarkably higher than those of aseptic rennet curd after 12 days ripening. This tendency was more remarkably recognized after 60 or 70 days ripening. α_s-Casein was mainly hydrolyzed by these lactic acid bacteria during ripening. α_s-Casein in two kinds of the cheese was more easily degradated by these lactic acid bacteria than that in aseptic rennet curd by rennet.
Judging from the results in previous and present reports, it was estimated that lactic acid bacteria used as a starter began to autolyze after 12 days ripening and that intracellular proteases released from their cells mainly hydrolyzed α_s-casein contained in Ca-paracaseinate of aseptic rennet curd to water soluble substances. This hydrolysis was also estimated from the viscous texture observed by scanning electron micrography.

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A flavoprotein was purified from rice embryo by means of ammonium sulfate fractionation, ion-exchange chromatography on CM-Sephadex C-50 and DEAE-Sephadex A-50, and gel filtration chromatography on Sephadex G-75 and G-100. A molecular weight of 37000 was determined by gel filtration on Sephadex G-100. The flavoprotein was shown to be homogeneous, with a sedimentation coefficient of 2.5S, in the sedimentation analysis, and exhibited an absorption spectrum characteristic of flavoprotein with absorption maxima at 276, 394 and 443mμ and shoulders at about 435, 465 and 485mμ. The prosthetic group of the protein was identified as flavin adenine dinucleotide. The flavoprotein was found to resemble the spinach chloroplast NADPH diaphorase in a number of aspects so far examined.

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The flavoprotein highly purified from rice embryo has been shown to have not only NADPH diaphorase activity but also ferredoxin NADP reductase and pyridine nucleotide transhydrogenase activities. The enzyme catalyzed the reduction of various artificial electron acceptors such as 2, 6-dichlorophenol indophenol, potassium ferricyanide, and quinone with the strict requirement for NADPH as the electron donor. The pH optimum and the affinities of the enzyme for 2, 6-dichlorophenol indophenol and NADPH have been determined. Close similarities of enzymatic properties were found between the rice embryo flavoprotein and the spinach chloroplast NADPH diaphorase. The physiological role of the enzyme is discussed in relation to the cellular metabolism in nongreen tissues of higher plants.

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Peptic hydrolyzate of soy protein was submitted to the plastein reaction with α-chymotrypsin under the following condition: substrate concentration, 20%; enzyme-substrate ratio by weight, 1/100; reaction pH, 7.0; and reaction temperature, 37°C. The plastein yield resulting from the plastein reaction for 24 hr was found to depend on the degree of hydrolysis of the substrate (per cent ratio between nitrogen amount in 10% trichloroacetic acid soluble nitrogen and that in whole hydrolyzate); the optimum degree of hydrolysis for the highest plastein yield seemed to lie around 80%. A turbidity appeared in the process of the plastein reaction, whose intensity was correlative to the plastein yield. The peptic hydrolyzate of soy protein per se had bitterness and its magnitude decreased with increasing plastein yield.
As a result of the plastein reaction applied for 24 hr to the hydrolyzate whose degree of hydrolysis was 80%, the average molecular weight estimated by the change in amino nitrogen content increased by approximately three times. The molecular weight distribution pattern obtained by gel filtration supported the above result. The total amount of amino acids liberated from the plastein reaction product by its treatment with either leucine aminopeptidase or carboxypeptidase A was significantly less than that liberated from the original hydrolyzate by its similar treatment. This result also supports the formation of higher-molecular protein-like substances by the plastein reaction. Deuteration study followed by IR spectrometry showed the occurrence of peptide bond formation, i.e. decrease in ionized carboxyl group at 1575cm^-1 and increase in deuterated amide at 1450cm^-1, even at the earlier stages of the plastein reaction.

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A bitter proteolyzate obtained by incubating soy protein with pepsin under the conventional condition contained 80.0μmole% glycyl-L-leucine (Gly-Leu) and 64.7μmole% L-leucyl-L-phenylalanine (Leu-Phe). On treating the bitter proteolyzate with α-chymotrypsin under the condition for plastein synthesis, the resulting product showed no bitterness and contained neither Gly-Leu nor Leu-Phe. Both Gly-Leu and Leu-Phe were insusceptible to the α-chymotryptic hydrolysis under this reaction condition. When the peptic proteolyzate to which either Gly-Leu or Leu-Phe was added (final content: 500μmole% each) was submitted to the plastein reaction, Gly-Leu and Leu-Phe disappeared within 12hr and 4hr, respectively, in spite of their insusceptibility to the α-chymotryptic hydrolysis. When the peptic proteolyzate to which a large amount of either Gly-Leu or Leu-Phe was added (final content: 500mmole% each) was submitted to the plastein reaction, the 50% aqueous ethanol insoluble core from each plastein-reaction product contained, as its constituents, significantly increased amounts of either glycine and leucine, or leucine and phenylalanine. Free glycine, leucine and phenylalanine each, however, did not participate the plastein synthesis. Accordingly it is concluded that, so far as the bitter peptides, Gly-Leu and Leu-Phe, are concerned, they play roles of plastein-building blocks, constitute the plastein in co-operation with other peptides in the peptic proteolyzate, and are hence deprived of their bitterness. In the case of Gly-Leu, its leucine terminus was mostly participant of constituting the plastein and, as a result, the glycyl-L-leucyl residues seemed to localize rather in the N-termini of the plastein chains. In the case of Leu-Phe, its both termini participated the plastein synthesis and, consequently, the L-leucyl-L-phenylalanyl residues seemed to be distributed almost uniformly in the plastein chains.

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Repression of maleate cis-trans isomerase(maleate isomerase) by carbon sources and its reversal were investigated by using Alcaligenes faecalis IB-14.
The formation of maleate isomerase was induced by malonate favorably in a poormedium, whereas it was repressed in a rich medium by carbon sources such as intermediates of TCA cycle. The repression provoked by DL-malate was accompanied with remarkable promotion of the cell growth and with accumulation of a large amount of pyruvate. The enzyme levels of TCA cycle were elevated several times in the DL-malate repressed cells. It was probable to assume that the formation of maleate isomerase was subject to catabolite repression when a rapid and surplus metabolism of DL-malate via TCA cycle was conducted.
So, as an approach to reveal the chemical nature of the catabolite moiety, reversal of the catabolite repression was studied. It was demonstrated that the repression provoked by DL-malate was reversed by various cultural conditions as follows; addition of higher concentrations of malonate, divided supply of DL-malate, “anaerobic” incubation and addition of higher concentrations of ammonium ion. From physiological significances of these events, it was revealed that catabolite repression of maleate isomerase was reversed by minimizing the functioning of TCA cycle.

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The essential oil of Mentha japonica Makino (Japanese name, Himehakka) was found to consist mainly from l-menthone (50.8%), d-isomenthone (18.6%) and d-pulegone (12.6%) besides smaller amounts of α-pinene (0.4%), β-pinene (0.3%), limonene (0.3%), 3-octanone (3.6%), 1, 8-cineole (0.8%), p-cymene (0.1%) 3-octyl acetate (0.8%), 3-octanol and a ketone (1.9%), 3-methylcyclohexanone (0.1%), l-octen-3-ol (0.9%), menthyl acetate (1.8%), l-isopulegone (0.6%), menthol (0.4%), piperitone (2.6%), trans-pulegone oxide (0.4%), iso-piperitenone (0.4%), cis-pulegone oxide (0.4%), piperitenone (0.2%) and other compounds.
Some considerations to the relationships among M. Pulegium, M. Gattefossei and M. japonica have been done from viewpoint of the chemical systematics.

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A tyrosine auxotroph derived from a hydrocarbon utilizing bacterium, Corynebacterium sp. KY 4309, was found to accumulate a large amount of L-phenylalanine in the broth. The cultural conditions for L-phenylalanine production were studied. The pH value during cultivations exhibited_??_remakable effect on L-phenylalanine production. The addition of L-tryptophan enhanced the L-phenylalanine accumulation. Shikimic acid and phenylpyruvic acid are possible precursors of phenylalanine biosynthesis in this bacterium. Production of L-phenylalanine attained to a level of 10mg per ml for 68hr under optimal conditions.

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Water soluble polysaccharides from the buckwheat endosperm was fractionated by salting out and a DEAE-cellulose column (phosphate form) chromatography and the main component (polysaccharide A1) was isolated as an ultracentrifugally and electrophoretically pure preparation.
The content of polysaccharide A1 in the buckwheat endosperm was 0.1_??_0.2%.
Its water solution showed high viscosity and [a]D was +39.4° The molecular weight was 240, 000-260, 000.
Polysaccharide A1 consisted of xylose, mannose, galactose and glucuronic acid. The hydrolysis of methylated polysaccharide A1 gave 2, 3, 4-tri-O-methyl-xylose, 2, 3, 4, 6-tetra-O-methyl-galactose, 2, 4, 6-tri-O-methyl-galactose, di-O-methyl-mannose and 4-O-methyl- and 5-O-methyl-glucuronic acid. These results suggested that the main chain of this poly-saccharide consisted of glucuronic acid, mannose and galactose and the former two occupied branching position with xylose and galactose residues as nonreducing end.

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1. The IC conformation was estimated for α-D-galactopyranosiduronic acid moiety of pectic acid in the permethylated derivative dissolved in 1N NaOD-D₂O and in the per-acetylated derivative dissolved in dimethyl sulfoxide-d₆, and the Cl conformation was estimated for some derivatives of D-galactopyranuronic acid in chloroform-d by NMR spectroscopy.
2. Random conformation of the whole macromolecule was estimated for pectic acid in water on the basis of no appearance of any induced Cotton effects in the 200_??_700mμ region in the ORD spectra of pectic acid-anionic dye complexes.
3. The conformation was supported by the fact that the rate of periodate oxidation of pectic acid at 5° was slightly decreased in comparison with that of amylase in 7M urea solution.

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(±)-Lamprolobine, the (±)-enatiomer of which was isolated from the leaves of Lam-prolobium fruticosum, and (±)-epilamprolobine were synthesized from δ-valerolactam.

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Carbonyl compounds in calf liver stored at 4°C for 5_??_6hr after slaughter were investigated, with emphasis on α-ketoaldehydes. After conversion of carbonyls into their 2, 4-dinitrophenylhydrazones (2, 4-DNPs), they were fractionated by preparative thin-layer chromatography (TLC); at least, twenty-three fractions were separated, among which eighteen fractions contained 2, 4-DNPs of α-dicarbonyls. From some of the fractions, crystalline 2, 4-DNPs were isolated, and identified by TLC and infrared spectra: pyruvalde-hyde, 3-deoxypentosulose, xylosulose, 3-deoxyglucosulose, 2, 3-diketogulonic acid or/and dehydroascorbic acid, and formaldehyde were identified, and glucosulose was tentatively identified.
The carbonyl pattern, obtained from rabbit liver frozen in liquid nitrogen immediately after slaughter, was also similar as that from calf liver, and further, the amount of each α-ketoaldehydes remained at the almost same level during storage at 4°C for 24hr. These results indicate that the identified α-ketoaldehydes are constituents or metabolic intermediates in calf and rabbit livers.
The formation mechanisms of the carbonyls in tissues are discussed.

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A variety of the thiolsulfonates (III) of dihydronereistoxin and its homologs were syn-thesized. The thioltosylates (III: R₄=T_s) were converted into the 1, 2-dithiolanes (IV) on treatment with alkali.

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Leaf oils from 6 domestic citrus species were analysed by gas chromatography and 32 compounds were identified as constituents of one or more oils. Most components present were common to all 6 citrus leaf oils, but the percent composition of some components, i.e. β-pinene, limonene, β-phellandrene, γ-terpinene, p-cymene, p-α-dimethylstyrene, citronellal, linalool and thymol methyl ether, differed considerably from species to species. For ex-ample, γ-terpinene is a main component (36.5%) of Shiikuwasha (Citrus depressa Hayata), but is a trace in leaf oils from Kawabata-mikan (C. aurea Tanaka) and Otaheite-orange (C. limonia Osbeck var. otaitensis Tanaka). Yuzu (C. Junos Sieb. ex Tanaka) is characterized by relatively high contents of β-phellandrene (11.2%) and p-α-dimethylstyrene (6.7%), which are minor constituents in the other 5 citrus leaf oils. Otaheite-orange is character-ized by high contents of limonene (39.7%) and citronellal (10.0%).

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A rapid and sensitive method is presented for the determination of micro-quantities (1 to 10μpg) of N-methyl carbamates as dinitrophenyl methylamine (DNP-MA) by electron capture gas liquid chromatography (GLC). The method described is characterized by rapidity and simplicity of procedure due to an improvement made in the present investigation, i.e., hydrolysis of an N-methyl carbamate and dinitrophenylation of the resulting methylamine with 2, 4-dinitro-l-fluorobenzene (DNFB) were accomplished simultaneously in a single reaction mixture. A novel approach was also made to eliminate unreacted DNFB by conversion to dinitrophenyl glycine (DNP-glycine).

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