A wild yeast, Candida utilis ATCC 42402, was found to secrete a glucomannan together with invertase on the consumption of sugar from the medium. The glucomannan in the culture filtrate was readily separated from the invertase by DEAE-cellulose chromatography. The crude glucomannan thus obtained was fractionated on a column of DEAE-Sephadex A-25 into several types of molecular species. The fractions were characterized by their sugar and amino acid composition which showed a tendency for an increasing mannose/glucose ratio, (1.66 - 5.74) coincident with greater amounts of the proteinous moiety (0.6 - 6 %). One fraction from the DEAE-Sephadex A-25 separation, which was distinct from the other fractions in its lack of glucosamine as a component, showed a high homogeneity (M.W., 7.4 × 10⁴ S_{W, 20} = 6.11 S).

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The structure of an extracellular glucomannan produced by Candida utilis was studied. Up to 15% hydrolysis of the glucomannan with the α-mannosidase isolated from Arthrobacter GJM-1 did not alter its viscosity. Sequential treatment of the glucomannan with periodate, borohydride and 0.1 N HCl gave a nondialyzable periodate resistant portion which amounted to 15% of the original glucomannan. The carbohydrate residue of the periodate resistant portion was found to consist only of mannose. Methylation analysis indicated that all the glucose residues in the molecule were doubly branched at the C 3 and C 4 positions, and the non-reducing ends were composed of only mannose. Partial hydrolysis of the glucomannan yielded di-(PHP 1, 2), tri-(PHP 3), tetra-(PHP 4) and pentasaccharides (PHP 5) which were isolated by TLC. They all contained one mole of glucose residue per mole of oligosaccharide. Arthrobacter α-mannosidase completely hydrolyzed PHP 1 to glucose and mannose, but did not hydrolyze PHP 2. In addition, the enzyme degraded PHP 3 and 4 into PHP 2 and mannose, and PHP 5 into mannose and a tetrasaccharide which did not correspond to any of the series PHP 1-5. The structures of these oligosaccharides were studied, by a joint analyses using methylation and α-mannosidase digestion.

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For the production of extracellular lipase by Alcaligenes species No. 679, NaNO₃, polyoxy-ethylene alkyl ether, Fe ^{+ +}, sodium citrate and fructose were found to be effective. The enzyme was prepared by acetone precipitation from the filtrate of the culture broth of this strain. The enzyme was most active at pH 9.0 and 50°C, while 35% of its activity was lost on heat treatment at 60°C for l0min. Sodium salts of bile acids stimulated the enzyme activity. This lipase could hydrolyse natural fats and oils as well as olive oil. During the hydrolysis of olive oil, monoglyceride was found to accumulate up to 70 mol percent. This lipase possesses special properties similar to those of pancreatic lipase as shown in the comparative experiments.

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Sepharoylaminocaproyl-3-chloroanilide (Sepharose-CH-3-Cl-anilide) was found to be an effective affinity adsorbent for a swep hydrolyzing enzyme from Paecilomyces varioti. It was adsorbed on this affinity column at pH 8.0, and eluted with 0.25 M NaCl in the starting buffer. From the active fractions, two enzymes were separated by the Sephadex G-200 column. One was termed swep hydrolase, hydrolyzing both swep and propanil. The other one was named propanil hydrolase, hydrolyzing only propanil.
The purified swep hydrolase appeared homogeneous on SDS disc electrophoresis, and the molecular weights of the enzyme and the subunit were 280, 000 and 70, 000, respectively. The isoelectric point of this enzyme was pH 4.8.

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Both (Z)-3-hexen-l-ol and cis-jasmone were synthesised via 1, 4-selective hydrogenation of conjugated dienes in the presence of arene Cr(CO)₃ or Cr(CO)₆ catalysts as the key step.

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Blue-green algae, commonly called "Aoko, " were taken from Lake Kasumigaura in Japan and the components which contributed to the rotten odor of the algae were analyzed by gas chromatography and computerized gas chromatography-mass spectrometry. Vacuum distillation of the algae in a frozed state was the best method for effectively isolating volatiles and odorous components without changes. Large amounts of alcohols, fatty acids and esters were detected in rotten algae in contrast with fresh algae. The main malodorous component in rotten algae was butanoic acid. Other odorous compounds were butanol, 3-methylbutanol, 3-methylbutanoic acid, hexanoic acid, butyl butanoate and butyl hexanoate.

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The accumulation of oil in maturing safflower seeds was studied with an electron microscope. It was suggested that net-like clusters of proteinaceous particles in the cytoplasm are the site of triacylglycerol synthesis. No evidence was obtained to support the hypothesis that oleosomes originate in the, endoplasmic reticulum. A hypothesis has been proposed that triacylglycerols are initially synthesized by the net-like clusters in the cytoplasm to form a protein-oil complex, and the triacylglycerols are concentrated in the center of the cluster as their formation proceeds.

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Cells of Pseudomonas strain C-120, cultivated under the conditions in which cells do not flocculate naturally, were flocculated with DNA prepared from Escherichia coli, indicating that DNA binding factor was constitutively present on the cell surface. On the other hand, release of DNA into the growth medium was observed accompanying flocculation of cells. The results suggest that release of DNA from cells is an important factor for flocculation. DNA binding activity of cells was abolished by treating cells with proteases, suggesting the DNA binding factor is a pro-teinaceous component. The effects of salts and 2, 4, 6-trinitrobenzene sulfonic acid on the cells suggested that amino groups were involved in the DNA binding reaction. The number of DNAs bound per cell was estimated to be about 10 molecules from reconstitution experiments using phage T₄ DNA.

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An acidic polysaccharide (APS-H) purified from the hemicellulosic fraction of the midrib of Nicotiana tabacum was composed of D-galacturonic acid, L-rhamnose, L-arabinose and D-galactose in a molar ratio of 31.8:15.4:9.9:42.9. Its molecular weight was estimated to be 90, 000 by gel filtration chromatography. APS-H had a pectin-like structure in which the rhamnogalacturonan backbone was composed of (1→2)-linked L-rhamnopyranosyl and (1→4)-linked D-galacturonosyl residues in a ratio of approximately 1:2.1. It also contained (1→4)-linked D-galactan and (1→5)-linked L-arabinofuranosyl moieties as the side chains. Branch points occurred mainly at C-4 of (1→2)-linked L-rhamnosyl residues in the backbone and at C-6 of (l→4)-linked D-galactosyl residues in the side chains.

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Nondialyzable melanoidin formed in a model system of glucose and glycine was applied on thin layer gel electrofocusing in a polyacrylamide gel. The electrofocusing profile differed according to the reaction time: the pI of the melanoidin formed in the early stage of the reaction was less than 2.9 and, as the reaction progressed, the pI of the melanoidin formed gradually shifted to a less acidic value, from 2.9 to 3.3. Those from the xylose and glycine model system gave a similar profile to that of the glucose system.
Preparative separation of the nondialyzable melanoidin, which was formed by heating the glucose system for 7hr, was performed by flat-bed electrofocusing in Sephadex gel. At least 14 melanoidin bands were clearly electrofocused at a pH range of 2.7 - 3.3 and about 59% of the melanoidin applied remained unaffected by electrophoresis at the starting position. The major component of electrofocused melanoidin was pI 3.00, this being made up of 12.5% of the total amount of electrofocused melanoidin. The molecular weight of melanoidin affected by electrophoresis was about 25, 000, regardless of the pI value of the melanoidin components. The reducing activity, estimated by the potassium ferricyanide method, showed that the lower the pI of melanoidin, the higher was the reducing activity.
The addition of hydrochloric acid to the melanoidin solution caused it to gradually become viscous and the melanoidin was precipitated below pH 3.0 - 3.5, corresponding approximately to ampholite. This feature can be used as a method to prepare nondialyzable melanoidin in a short time.

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A simple and general synthetic method is described for erythro- and threo-forms of 2-amino-1, 3-diols with an acyclic terpenoid-type side chain. ¹³C-NMR data are given for the triacetyl and N-acetyl derivatives of the synthetic erythro- and threo-2-amino-l, 3-diols.

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A number of soil isolates belonging to the genus Trichoderma were found to produce isonitrins A, B, C and D and isonitrinic acids E and F, a new class of antibiotics characterized by the presence of isonitrile groups. Taxonomy of the producing organisms, fermentation, isolation and physicochemical and biological properties of isonitrins and isonitrinic acids are reported. Isonitrin A showed the highest in vitro antimicrobial activities against gram-positive and negative bacteria and fungi.

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Seventy-five strains belonging to the genus Trichoderma were examined for production of isonitrile antibiotics. The results indicated that the production patterns and the morphological and physiological characteristics had good correlation: that is, each species exhibited its own characteristic production pattern of isonitrile antibiotics.

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Two potent gastroprotective substances against experimental gastric ulcers in rats induced by stress and five of their analogues were isolated from the culture broth of bacterial strain AI-77 which was classified taxonomically as Bacillus pumilus. Physico-chemical properties and pharmacological activities of the seven compounds were examined and compared with each other.

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A myeloma MPC-11 cell line, which originated in a mouse plasma cell tumor, was able to proliferate in the absence of serum in a synthetic medium supplemented with transferrin, ethanolamine and selenium. The cells showed almost the same growth rate in this medium as in medium with 10% fetal calf serum added. Immunoglobulins secreted into the serum-free medium by the cells were easily separated from medium components by polyacrylamide gel electrophoresis.

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Hydroxycinnamic acid ester hydrolase from the wheat bran culture medium of Aspergillus japonicus was purified 255-fold by ammonium sulfate fractionation, DEAE-Sephadex treatment and column chromatographies on DEAE-Sephadex, CM-Sephadex and various other Sephadexes. The purified enzyme was free from tannase and found to be homogeneous on polyacrylamide disc gel electrophoresis. Its molecular weight was estimated to be 150, 000 by gel filtration and 142, 000 by SDS-gel electrophoresis. The isoelectric point of the enzyme was pH 4.80. As to its amino acid composition, aspartic acid and glycine were abundant. The optimum pH and temperature for the enzyme reaction were, respectively, 6.5 and 55°C when chlorogenic acid was used as a substrate. The enzyme was stable between pH 3.0 to 7.5 and inactivated completely by heat treatment at 70°C for l0min.
All metal ions examined did not activate the enzyme, while Hg⁺⁺ reduced its activity. The enzyme was markedly inhibited by diisopropylfluorophosphate and an oxidizing reagent, iodine, although it was not affected so much by metal chelating or reducing reagents. The purified enzyme hydrolyzed not only esters of hydroxycinnamic acids such as chlorogenic acid, caffeoyl tartaric acid and p-coumaroyl tartaric acid, but also ethyl and benzyl esters of cinnamic acid. However, the enzyme did not act on ethyl esters of crotonic acid and acrylic acid or esters of hydroxybenzoic acids.

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Azaserine-resistant mutants derived from a 5-fluorotryptophan-resistant, L-tryptophan-producing mutant of Brevibacterium flavum, accumulated 10.3 g/liter of L-tryptophan at maximum. The production increased to 11.4 g/liter when L-serine was added. In the mutant, only anthranilate synthase among enzymes of the tryptophan-specific biosynthetic pathway increased in activity to a 2-fold higher level than that in the parent strain, No. 187. Sensitivity of anthranilate synthase to the feedback inhibition was not altered by the mutation. Activity of 3-deoxy-D-arabino-heptulosonate 7-phosphate synthase, the first common enzyme for aromatic amino acid biosynthesis, also increased 2.7-fold and was less sensitive to the feedback inhibition by phenylalanine and tyrosine. Tryptophan transport activity in strain A-100 was similar as that in the parent. Azaserine inhibited anthranilate synthase activity by 50% at 0.075 mM. The inhibition was of a mixed type with respect to both the two substrates. Anthranilate synthase of strain A-100 was inhibited in a similar manner to that of the parent.

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Against the mold mite, Tyrophagus putrescentiae, 3, 7-dimethyl-(Z)-2-octenyl formate (II) is the most active compound as an alarm pheromone besides the natural pheromone, neryl formate (I), and this activity is equal to I (1-10ppm). In order to elucidate the structural requisites for inducing alarm pheromone activity, a total of 16 analogues of I were prepared by modifying the structure of II. For preparation of 3-methyl- and 3-ethyl-(Z)-2-alkenyl formates, the Wittig reaction of ethoxy- or methoxy-carbonylmethylene triphenyl phosphorane with 2-alkanone or 3-alkanone was used. The reaction with 2-alkanone gave a mixture of (Z)-2-alkenoate (ca. 40%) and (E)-2-alkenoate (ca. 60%) in an average 60% yield. The reaction with 3-alkanone gave a mixture of (Z)-2-alkenoate (56%) and (E)-2-alkenonate (44%).
Alarm pheromone activities were demonstrated on 14 compounds of (Z)-2-alkenyl formates. The presence of the (Z)-allylic primary alcohol formate moiety in a molecule was clarified as the key to induce pheromone activity, and no necessity for an acyclic monoterpene carbon skeleton was demonstrated.

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Two paralytic shellfish toxins, gonyautoxin V and gonyautoxin VI, isolated from a tropical dinoflagellate, pyrodinium bahamense var. compressa, were identified respectively to be derivatives of saxitoxin and neosaxitoxin with a sulfonatocarbamoyl moiety.

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Stereoisomers and analogues of amastatin, [(2S, 3R)-3-amino-2-hydroxy-5-methylhexanoyl]-L-Val-L-Val-L-Asp, were synthesized and their inhibitory activities towards aminopeptidase A (AP-A) and other arylamidases tested. Among the four stereoisomers of a new amino acid residue in amastatin, the 2S stereoisomers exhibited strong activity. In a series of compounds in which the C-terminal amino acid of amastatin was substituted by other amino acids, the one containing Asp or Glu showed the strongest activity towards AP-A. In a series of compounds in which the second or third residue from the amino terminal of amastatin was substituted by other amino acids, the one containing hydrophobic amino acids showed strong activity. In the study of the relationship of the length of the peptide chain and inhibitory activity, the activity towards AP-A was seen to increase until the length of the peptide reached that of a tetrapeptide.

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The attractive and characteristically sweet aroma components of baelfruit -a tropical fruit- were investigated. The aroma concentrates possessing the sweet floral and somewhat terpene-like aroma were obtained from both the pulp and peel of fresh baelfruits by means of lyophilization and ether extraction, being analyzed mainly by GC-MS. A total of 39 components were identified. Among these components, terpene alcohols and β-ionone were considered to contribute to the aroma of baelfruit. At optimum ripeness, the fruit with excellent flavor contained a large quantity of an isomeric compound of 3, 7-dimethyl-1, 5, 7-octatnen-3-ol. This compound couldn't be found in unripe fruit, and seems to be important in making the baelfruit flavor attractive.

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Synthesis of (±)-phyllostine, (±)-epoxydon, (±)-epiepoxydon, (±)-epoformin and (±)-epiepoformin by the retro-Diels-Alder reaction was described.

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The new peptide antibiotics have been obtained from the culture filtrate of a streptomycete, strain 248-Sq2, isolated from a soil sample collected at Nagano Prefecture, Japan.
On the basis of taxonomic studies, the producing organisms is designated as Streptomyces cirratus. Two active principles are named cirratiomycin A and B.
These antibiotics exhibit a narrow range of activities against Lactobacillus casei and some strains of Streptococcus and Mycobacterium.

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The structures of cirratiomycin A and B have been elucidated by a degradative study and 1H-and ¹³C-NMR spectral analysis It is revealed here that cirratiomycin A and B are heptapeptides containing three unusual new ammo acids, viz, hydroxymethylserine, 2, 3, 4, 5-tetrahydropyndazme-3-carboxyhc acid and 2, 3-didehydroisoleucine.

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By screening 46 strains of Actinomycetes for their ability to hydrolyze arabinan, 16 strains were found to have α-L-arabinofuranosidase activity, and Streptomyces purpurascens IFO 3389 was selected as the most promising of the sixteen. An α-L-arabinofuranosidase [EC 3.2.1.55] has been highly purified from the culture fluid of this organism grown on beet arabinan as the carbon source. The molecular weight of the native enzyme was determined to be 495, 000 by gel filtration and that of the subunit to be 62, 000 by SDS polyacrylamide gel electrophoresis. The pI value was 3.9. The purified enzyme was active on ρ -nitrophenyl α-L-arabinofuranoside and arabino-oligomers, and inactive on arabinan, arabinoxylan and arabinogalactan. The optimum pH was 6.5. The enzyme was inhibited by Hg ²⁺, Ag ⁺ and L-arabino-γ-lactone. The values of Km and V_max for ρ-nitrophenyl α-L-arabinofuranoside were determined to be 8.2 × 10^-5 M and 89.3 μmol per min per mg of protein, respectively.

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With pig liver esterase, 1, 3-dibenzyl-4, 5-cis-bis(alkyloxycarbonyl)-2-oxoimidazolidine (1) was asymmetrically hydrolyzed to (4S, 5R)-l, 3-dibenzyl-5-alkyloxycarbonyl-2-oxoimidazolidine-4-carboxylic acid (2). This acid 2 was reduced with lithium borohydride to (4S, 5R)-l, 3-dibenzyl-5-hydroxymethyl-2-oxoimidazolidine-4-carboxylic acid lactone (3), which is known to be converted to ( + )-biotin (4). With the same esterase, diethyl 3, 4-dimethoxyphenylmethyl-(methyl)malonate (5) was asymmetrically hydrolyzed to (R)-ethyl hydrogen 3, 4-dimethoxy-phenylmethyl(methyl)malonate (6), which can be converted to (S)-α-methyl-3, 4-dihydroxyphenyl-alanine(L-a-methyldopa) (9).

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