The growth factor for malo-lactic fermentation bacteria was partially purified from tomato juice, and some properties of the factor were examined. The factor was comparatively a low molecule, thermo-stable and insoluble in nonpolar organic solvents. The purified factor fraction showed positive reaction with Molisch-, tetrazolium- and Nessler-reagents, suggesting the existence of sugar and nitrogen as the chemical components. The treatment with cellobiase or cellulase-II resulted in the inactivation of the factor and simultaneously released the sugar constituent composed of glucose from the factor. These results indicated that the glucose residue might exist as the β-1, 4-glucosidic linkage in the growth factor.

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Solution containing L-leucine and L-methionine cultured by Aspergillus flavus were found to develop cheese-like flavor.
α-Keto-isocaproic acid was isolated and identified from the culture of L-leucine and α-keto-β-methylmercaptobutyric acid from that of L-methionine. The flavor was also developed from the mixture of the synthetic sample of α-ketoisocaproic acid and α-keto-β-methylmercaptobutyric acid.

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L-Arabinose ketol-isomerase (EC 5. 3. 1. 4) was extracted from the L-arabinose-grown cells of Clostridium acetobutylicum and partially purified by ammonium sulfate fractionation, DEAE-cellulose column chromatography and the gel filtration on Sephadex G-200.
Optimum pH and temperature for the activity of the enzyme were 7.5 and 37°C, respectively. The enzyme was inhibited by EDTA, Na-pyrophosphate and KCN, and its activity was restored by the addition of divalent metal ions such as Mn²⁺ and Co²⁺. The Michaelis-Menten's constants for L-arabinose, Mn²⁺ and Co²⁺ were 1.08×10^-2M, 0.83×10^-4M and 0.38×10^-4M, respectively. The equilibrium constant (K=ribulose/arabinose) was 3.14 (37◊C, pH 7.5). The thermodynamic quantities, ΔH, ΔG (37°C), ΔS (37°C) and E were +7354cal/mole, -710.7cal/mole, +26.0cal/(deg•mole) and +7471cal/mole, respectively.

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Screening test for obtaining microorganisms which produce L-amino acids and organic acids from n-paraffins were carried out.
It was found that fourteen strains of microorganisms which seemed to belong to yeast showed strong ability to produce α-KGA.
A representative strain of these microorganisms was identified taxonomically as Candida lipolytica (AJ 5004).
Investigations for obtaining optimal conditions for production of α-KGA using Candida lipolytica AJ 5004, were carried out and the results were as follows:
1) Organic nitrogen compounds, such as polypeptone, yeast extract, meat extract and corn steep liquor increase the yeast growth.

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Rats were divided into low casein diet and high casein diet fed groups, and the fatty acid composition of liver mitochondrial phosphatides was analyzed. It was found that in liver mitochondrial phosphatides the value of arachidonic acid decreased slightly, and that of the polyenoic fatty acid which was infered as 4, 7, 10, 13, 16-docosapentaenoic acid increased by low casein diet. The analysis was performed also on whole liver phosphatides. There was no great difference between the fatty acid composition of whole liver and liver mitochondrial phosphatides

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Glucose 6-phosphate and 6-phosphogluconate dehydrogenase activities of sliced sweet potato root tissue increased markedly during aerobic incubation at 30°C in a moist atmosphere. One band of glucose 6-phosphate and at least 3 bands of 6-phosphogluconate dehydrogenase were observed in the disc electrophoresis zymograms of the crude extracts. The marked differences were absent between fresh and sliced tissues. The intensity of the most rapidly migrating band of 6-phosphogluconate dehydrogenase seemed to increase in response to slicing.

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A bacterium isolated in our laboratory, Arthrobacter poraffineus KY 4303, when grown on an n-alkane as the sole source of carbon, accumulated anthrone-positive substances in the culture medium. These were isolated in crystalline forms and identified respectively as α, α-trehalose and D-glucose.
The addition of penicillin to the growing culture led to a remarkable increase in the accumulation of trehalose. It attained to approximately 5 to 6g per liter, corresponding to 60_??_70% of total sugars accumulated in the culture medium.
Extracellular accumulation of these sugars was also observed in other bacteria which can utilize n-alkanes as the sole source of carbon.

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Isolation and purification procedures of yeast pro-proteinase C are described. In order to obtain a good yield of the proenzyme, it was necessary to repeat the inactivating treatment of coexisting yeast proteinase A and to perform purification procedures as rapidly as possible at low temperature. The purified protein was homogeneous with respect to chromatographic, electrophoretic and sedimentation criteria. The proenzyme possessed no inherent activity for acetyl-L-tyrosine ethylester but a slight activation seemed to occur during the activity assay. The molecular weight of the proenzyme was 79, 200 as determined by the sedimentation and diffusion methods. Its other physicochemical properties were compared with those of proteinase C. The proenzyme as well as proteinase C was shown to be a glycoprotein which contains 8_??_12% true sugars.

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Metabolic function of Gluconobacter melanogenus toward sorbitol and related sugar derivatives was examined by using resting cells of the organism. From the results, together with the previous findings obtained by the growing cultures, the overall pathway of sorbitol metabolism in G. melanogenus was proposed as presented in Fig. 2.

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L-Glutamic acid was formed from D-, L-, and DL-PCA with Cell-free extract of Pseudomonas alcaligenes ATCC-12815 grown in the medium containing DL-PCA as a sole source of carbon and nitrogen. The enzyme(s) involved in this conversion reaction was distributed in the soluble fraction within the cell and in 0.5 saturated fraction at the fractionation procedure with the saturation of ammonium sulfate. Optimum pH of this enzyme(s) lied at pH 8.5 and optimum temperature was 30°C. Cu (5×10^-3M) inhibited the reaction considerably while Ca or Fe accelerated it. PALP (1×10^-3M) also gave an enhanced activity to some extent. The enzyme preparation converted dextro-rotatory enanthiomorph of PCA to its laevo-rotatory one which in turn was not converted to the opposite rotation direction by this enzyme. Furthermore, the preparation did not, if any, show D-glutamic acid racemase activity. Isotopic experiments with using DL-PCA-1-¹⁴C revealed that L-glutamic acid-1-¹⁴C was formed by the cleavage of -CO-NH- bond of pyrrolidone ring of PCA. It was concluded that DL-PCA when assimilated by the present bacterium is at first transformed to L-PCA by the optically isomerizing enzyme and subsequently is cleaved to L-glutamic acid probably by the PCA hydrolysing enzyme.

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Four components of ovomucoid were digested exhaustively and four kinds of glycopeptide corresponding to the four components were separated by gel filtration. Each glycopeptide was shown to be homogenious by paper chromatography and paper electrophoresis. Molar ratios of carbohydrate components of these glycopeptides varied to some extent but the amino acid compositions of thses glycopeptides were essentially identical with each other with the exception of alanine. Aspartic acid and threonie were predominant amino acids in the all glycopeptides. It is most likely that the modes of linkages between polysaharide and protein in individual ovomucoid I, II, III and IV are essentially the same, and that the c arbohydrate moiety is linked to the protein via asparaginyl residue or the hydroxyl group of threonine, although the possibility of the linkages to glutamine and serine can not be excluded.

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Homologous 4- and 5-substituted 5-hydroxy-2-enoic acid lactone were prepared, and the nature of their flavors as a butter cake flavor was investigated. Among those, unsaturated lactones having the best flavorous nature have the following structural properties. The length of a substituted residue at the γ-position of the lactone ring should be a short as possible. The lactones have a n-amyl residue at the δ-positio, and the total carbon number of a compound is ten. Namely, a compound is so better as to have a structure similar to that of 5-hydroxy-2-decenoic acid lactone.

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The presence of psicofuranine in the fermentation meduim caused the accumulation of a copious amount of 5'-XMP by brevibacterium ammoniagenes. The accumulation of 5'-XMP in the meduium was considered to be due to the inhibition of converting 5'-XMP to 5'-GMP by psicofuranine, which is known as a specific inhibitor of XMP aminase.
It was previously repored that in 5'-IMP fermentation with Br. ammoniagenes pantothenate and thiamine, in addition to biotin which was required for the growth of the microogrganism, were exclusively required. This requirement for both vitamins was also observed in 5'-XMP production induced by thed antibiotic.
The addition of manganese in excess to the fermentation medim promoted the bacterial growth greatly and inhibitedd IMP production, whereas XMP Production induced by piscofuranine wa not affected by the addition of excess manganese.
The accumulation of XMP induced by the antibiotic was completely suppressed by the presence fo purine derivatives such as guanine, and xanthine deriatives, and partially by hypoxanthine.
5'-XMP was identified by chemical and enzymatic analyse and UV absorption spectrum.

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Gigartinine and gongrine, both isolated from the red alga, Gymnogongrus flabelliformis, were confirmed by synthesis to be L-α-amino-δ-(guanylureido)-n-valeric acid and γ-(guanylureido) butyric acid, respectively. DL-Gigartinine was synthesized from α-chloro-δ-amino-n-valeric acid through esterification, phosgenation, condensation with guanidine, hydrolysis, and Rf values in paper chromatography agreed well with those fo natural L-gigartinine. Another guanylureido compound identical with natural gongrine was obtained from γ-amino-butyric acid through phosgenation followed by condensation with guanidine.

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Pork fat was heated at 160-170°C for 3 hr under bubbling with air, and the volatile compounds were collected in the cold trap. After the acidic compounds were removed from the volatile compounds by extraction with 3% aqueous sodium carbonate solution, lactones were obtained from the nonacidic compounds by saponification. Gas chromatographic analyses of lactones were carried out on the PEG-20M and Apiezon L packed columns, and then each lactone was fractionated by repeated gas chromatography. Each isolated lactone was identified by infrared spectrometry, and also three major lactones were identified by mass spectrometry. Consequently, γ-C₅-C₁₂ and δ-C₉, δ-C_l0, δ-C₁₂ and δ-C₁₄ lactones were found in the flavor of heated pork fat. Gamma-lactones, especially γ-C₇, γ-C₈ and γ-C₉, were predominant in the flavor, and unsaturated lactones were not detected. Mechanisms for the formation of the lactones were discussed.

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An intermediate radical, CH₂OH, was produced in aqueous methanol solution containing nitrous oxide by γ-irradiation. Yields of ethylene glycol and formaldehyde, the major and the minor product from CH₂OH, respectively, changed on the addition of some solutes. Cysteine lowered the both product yields to zero even at a low concentration of 5×10^-5M. Oxygen of low concentrations (2.5_??_7.5×10^-5M) changed effectively the major product from ethylene glycol to formaldehyde. k_(CySH+CH2OH)/k_(O2+CH2OH) was calculated as 0.5.
Ascorbic acid (5×10^-5M) lowered ethylene glycol yield to 48%, cystine (10^-3M) to 15%, methionine (10^-3M) to 31%, , histidine (10^-3M) to 42%, tryptophan (10^-3M) 46%, tyrosine (10^-3M) to 77%, phenylalanine (10^-3M) to 73%, hypoxanthine (10^-3M) to 37%, adenine (10^-3M) to 52%, uracil (10^-3M) to 20%, thymine (10^-3M) to 10%, cytosine (10^-3M) to 49%, rutin (10^-3M) to 23%, pyrogallol (10^-3M) to 41%, and gallic acid (10^-3M) to 78% of the control. These results suggest that the reactions of the secondary radicals such as CH₂OH perform an important role in material change of foods irradiated with γ rays.

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(-)-N-Methyl-2-deoxystreptamine ((-)-hyosamine)^* was synthesized from 1, 2, 4, 5/3-cyclohexanepentol. Acetobacter suboxydans was used in the first step for the asymmetric oxidation. The absolute configurations of (+)- and (-)-hyosamine and of the synthetic intermediates were discussed.

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The biosynthetic mechanism of 6-methyloctanoic and isooctanoic acids, which are present in the amide linkage with the α-amino group of the terminal α, γ-diaminobutyric acid residue of colistin A and B, respectively was investigated. From the isotopic experiments using isoleucine-U-¹⁴C, valine-U-¹⁴C and acetic acid-2-¹⁴C, it was concluded that 6-methyl-octanoic and isooctanoic acids were derived from isoleucine and valine, respectively.
Amino acids pooled in colistin-producing cells grown in the synthetic medium were abundant in isoleucine, valine and leucine, which were probable precursors of the above-described fatty acid components of colistin and cellular fatty acids. On the other hand, 6-methyloctanoic and isooctanoic acids were not found in the cellular fatty acids, while C-15 and C-16 branched chain fatty acids usually found in Bacillus sp. were abundantly contained in the cells, indifferently of an improved capacity of colistin formation.

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Volatile components obtainea by the extraction of “Katsuobushi” with 80% ethanol and by the subsequent steam distillation of the extract were fractionated by the usual methods, and the resulting hydrocarbon fraction was investigated. Gas chromatographic study on this fraction originated from “Katsuobushi” of bonito (Katsuwonus pelamis) revealed 9 hydrocarbons, including n-tetradecane, n-pentadecane, n-hexadecane, n-heptadecane, n-octadecane, n-nonadecane, n-eicosane, n-heneicosane and n-docosane, which were tentatively identified by the retention times with the aid of authentic hydrocarbons. n-Pentadecane and n-heptadecane that were main components among these hydrocarbons were identified further by NMR and IR spectrometry. “Katsuobush” of frigate mackerel (Auxis thazard), mackerel (Scomber, Japonicus Houttuyn) or muroaj i (Decapterus muroadsi) also contained n-penta-decane and n-heptadecane in large amounts, but did other hydrocarbons in negligible amounts.
Possible mechanisms of the hydrocarbon formation during the processing of “Katsuobushi” were discussed.

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When grown on medium containing ethanol as the sole carbon source, three of five strains of yeast tested produced a keto acid which was demonstrated by paper chromatography. This compound was isolated and its structure was examined by elementary analysis, infrared spectrum, nuclear magnetic resonance and periodate oxidation. The compound was proved to be identical with 5-hydroxy-4-ketohexanoic acid. Formation of this compound by cell suspensions of Hansenula miso IFO 0146 was achieved by addition of acetaldehyde, although the presence of α-ketoglutaric acid enhanced the formation of the keto acid from acetaldehyde during a short incubation period. Added 5-hydroxy-4-ketohexanoic acid was exhausted by the cell suspension.

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