Breaking activity of catecholamines and their structural analogues on λ DNA were investi-gated by agarose slab gel electrophoresis. Since λ DNA has a homogenous molecular size, it is a favorable material to detect the activity of DNA breaking reagent. Among the com-pounds tested, those having enediol group were only active, though their activities remarkably differed owing to their side chains. The profile of the breaking reaction was studied in detail by the use of one of the catecholamines, epinephrine.

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The degradation of starch by γ-irradiation and the effect of pH on gelatinization of starch after irradiation were investigated. Paste viscosities were markedly affected by pH on gelatini-zation and a decrease in the viscosity of irradiated starch was stimulated by increasing pH. On the other hand, the solubility of irradiated starch increased significantly at a high pH. The granule structure of irradiated starch easily disintegrated at alkaline pH. Remarkable dissolution from the surface of the irradiated starch granules was observed after heating at high pH only a filamentous network frame remained, but the unirradiated one collapsed and folded.
It was seen that alkali treatment after irradiation reduces the required dose to obtain low viscosity starch. The required dose to produce a low viscosity starch, for example Ajino-moto Essan Sizer 600 grade, was ca. 3 Mrad at pH 11.0 and ca. 5 Mrad at pH 7.0, whereas it was ca. 7 Mrad without pH adjustment.

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We have developed an analytical method for determining polynuclear aromatic hydro-carbons (PAH) in sediment using mass fragmentography (MF). MF, using the combination of a gas chromatograph-mass spectrometer, is superior because of quick separation, specificity of mass spectra and the high detection sensitivity. PAH extracted by a benzene-methanol mixture (10:3) were first applied to a florisil column in benzene to remove interfering com-pounds, and then applied to a silicic acid column to separate aliphatic hydrocarbons from PAH using isooctane as the elution solvent. PAH thus purified in the isooctane-benzene (1:1) fraction were identified and determined by MF.
Recoveries of the individual compounds in sediments were more than 80% in amounts ranging from 20 to 200μg. In the sediment collected from Hirakata Bay, PAH including fluoranthene, pyrene, 1, 2-benzanthracene, chrysene, 3, 4-benzpyrene (1, 2-benzpyrene), perylene and 1, 12-benzperylene, were identified and determined at concentrations ranging from 24 to 411μg/kg of dry sample.

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Fifteen derivatives of 5-substituted tetronic acid (VII) and five derivatives of 3-acetyl-5-substituted phenyltetramic acid (III) were prepared and their biological activities were investi-gated. Among the compounds tested, 3-carboethoxy derivatives of tetronic acid showed a remarkable stimulating effect on the growth of rice roots, while the compounds which were removed the carboethoxy group from their 3-position displayed a strong inhibitory effect on the growth of rice roots and stalks. The fungicidal activity against Asp. niger and the effects on pupation and emergence of the housefly were also investigated as to the compounds synthesized.

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Three kinds of lectins (LOL-I, II and 111) were isolated from seeds of Lathyrus odoratus (sweet pea) in a homogenous form. The three fractions agglutinated the erythrocytes of laying hens, and the agglutination was strongly inhibited by α-methyl D-mannoside and D-mannose. However, they did not agglutinate those of the males and nonlyaing hens, differing from concanavalin A which showed a similar binding specificity for monosaccharide to LOL and agglutinated all types of erythrocytes derived from chicken in this study. LOL-I and II had a molecular weight of 52, 000 and both consisted of two large (20, 000 daltons) and two small subunits (6000 daltons). LOL-111 had a molecular weight of 55, 000, and its subunit structure was different from those of LOL-1 and 11. The amino acid compositions of the three fractions were very similar. They contained large amounts of aspartic acid, threonine, serine and valine, but no cysteine or methionine. Circular dichroism measurements indicated that β-structure was a major secondary structure of these lectins. The addition of α-methyl D-mannoside or D-mannose had significant effects on the CD spectra in the near-ultraviolet region, but no detectable change was observed in the 200_??_250 nm region. LOL-I had two binding sites for D-mannose, and the association constant was about 1000 liters per mol.

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Acidic heteropolysaccharides, D-glucurono-D-xylo-D-mannans were isolated from the water- and alkaline extracts of the fruit body of Tremella fuciformis Berk. Similar poly-saccharides were isolated from the growing culture of the haploid cells of two strains (T-19 and T-7) of T. fuciformis, when they were cultured in sucrose or glucose-yeast extract medium. The extracellular polysaccharides contain, n-glucuronic acid, D-xylose and n-mannose [molar ratios, 1.3: 1.0: 3.5 (T-7) and 0.8: 1.0: 2.1 (T-19)], and, in addition, small proportions of L-fucose and O-acetyl groups. Methylation and Smith degradation studies indicated that both fruit body and extracellular polysaccharides are built up of α-(1→3)-linked D-mannan back-bone chain to which β-linked D-glucuronic acid and single or short chains of β-(1→2)-linked D-xylose residues are attached at the C-2 position. L-fucose residues in the extracellular poly-saccharides may form the single branches. The structural features of these polysaccharides are discussed in comparison with the similar polysaccharides from other fungi.

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A methanol-utilizing bacterium, Protaminobacter ruber, formed a green pigment, when it was grown on 1, 2-propanediol as a sole carbon and energy source. The pigment was identified as bacteriochlorophyll a by the absorption spectrum resembling the pigment from photosynthetic bacteria and by the exact stoichiometric relationship among the original pigment, the pigment treated to remove magnesium (bacteriopheophytin) and magnesium ion obtained from the pigment. Bacteriochlorophyll formation was stimulated by the ex-posure to light during the relatively early stage of the growth, while the continuous light exposure completely prevented the pigment formation. Aeration was also necessary for the pigment synthesis as well as the bacterial growth. Electron micrographs of thin section of P. ruber cells cultured in the intermittent light showed the probable existence of a chromatophore-like structure.

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d-Coronamic acid was deaminated by 1-aminocyclopropane-l-carboxylate (ACPC) deaminase to produce α-keto-n-caproic acid. This deaminase which was purified from Pseudornonas sp. ACP was active to only d-coronamic acid among its stereoisomers. l-Coronamic acid or dl-allocoronamic acid was inactive or negligibly poor as the substrate. In addition, both deamination of ACPC and d-coronamic acid were inhibited by L-alanine, not by D-isomer and the inhibition of ACPC deamination by L-alanine was competitive. On the basis of these results, stereoselectivity of the enzymatic deamination was discussed.

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The effect of tripropyltin chloride (TPT) on transport systems in E. coli was investigated. The inhibition on uptakes of ¹⁴C-L-leucine, L-proline, adenine and methyl-(α-D-gluco)pyrano-side (α-methylglucoside) by TPT was examined. The active uptake of L-leucine which utilized ATP molecule as an energy source was 100% inhibited at the concentration of 10μg/ml TPT. On the other hand, the uptake of L-proline which was generated by an “energied” membrane state of the cells was inhibited only 40% at the same concentration of TPT. α-Methylgluco-side uptake was scarcely inhibited. Adenine uptake was intensely inhibited at 20μg/ml TPT. The effect of the delayed addition of TPT on transport systems was also examined. L-Leucine incorporated into cells was completely released from cells by TPT. Leucine binding protein (LBP) was prepared from E. coli cells and the effect of TPT on LBP activity was examined. TPT scarcely inhibited LBP activity.

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The copper binding properties were influenced by growth phase of cells, pH and concen-tration of copper in reaction mixtures. The efficiency of copper absorption increased with growth time and was largest at the mid-logarithmic growth phase. The time course of copper absorption was biphasic, that copper rapidly bound to cell surface for initial few minutes after addition of copper and then the copper was slowly transported into cells. The copper binding to the cell surface depended on the molecular form of copper complex in the reaction mixture and the ligand residue to copper on the cell surface. Double reciprocal plots of ab-sorption velocity of copper vs. copper concentration gave straight lines at low concentration between 0.01 to 0.1 mM. The apparent affinity of copper to the cells of stationary growth phase was the same as that of logarithmic growth phase, that is, the Kmvalues were about 0.01mtg. On the other hand, at high concentration of copper between 0.1 to 5.0 rum the apparent affinity decreased but the absorption velocity of copper remarkably increased. Zinc sulfate most strongly inhibited the copper absorption in this test. It was assumed that zinc competitively bound to the copper binding sites of cell surface.

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The seedlings of rice, eggplant and tomato at the 5th leaf stage of growth readily ab-sorbed exogenous ¹⁴Cnieotinamide through the root and the foliage in water culture. Within the 24 hr period after the bigining of cultivation, the radioactivity gradually translocated from the part treated with ¹⁴C-nicotinamide to the whole plant body. This compound was rapidly metabolised in the plants to at least six metabolites, in which three compounds were identified as nicotinic acid, NAD and NADP. ¹⁴C-Nicotinic acid was also taken up quickly through the root of rice and its metabolism showed a similar pattern to that of ¹⁴C-nicotinamide. The incorporation of radioactivity into NAD and NADP from 14C-nicotinamide added to cultivating solution at a concentration of 0.21 ppm was decreased to 10-20% by the simul-taneous addition of unlabeled nicotinic acid at a concentration about 1000 times higher than that of the labeled one. It was concluded that the biosynthesis of these pyridine nucleotides from nicotinamide was chiefly via nicotinic acid. The formation of ¹⁴C-nicotinamide in the ¹⁴C-nicotinic acid metabolism suggested a breakdown of NAD. Three unknown com-pounds observed in both the metabolisms described above were not intermediates in the pyridine nucleotide biosynthesis.

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Phloroglucinol-type furocoumarins were found to have strong antifeeding activity against Spodoptera litura (tobacco cutworm), but the other furocoumarins belonging to pyrogallol-or resorcinol-type had only weak activity. Antifeeding activity of these compounds against the other insects was also reported.

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Purification and characterization of β₂-microglobulin from human urine was performed. The yield was 30.1%, and 150.4mg of β₂-microglobulin was obtained. The final preparation of β₂-microglobulin obtained showed three bands on disc gel electrophoresis at pH 9.5, and all of them have immunological activity. However, these three bands migrated as a single band on disc gel electrophoresis at pH 4.3. It is concluded that the three bands observed on disc gel electrophoresis at pH 9.5 were charge isomers. The isoelectric points of isomers were deter-mined by isotachophoresis and two of them were 5.4 and 5.9 respectively, while the other one was not determined.

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The relationships between gas chromatographic (GC) profiles and sensory data of 72 purely fermented soy sauce samples were analyzed by multiple regression analysis and principal component analysis (PCA). Prior to the analysis, GC data was transformed into 7 different modes in order to compare the fitting to a hypothetical linear model. The result from loga-rithmically transformed ratio of each peak to the sum of whole peaks showed the best precision of predictability for sensory score (R=0.978). As the result of PCA, eigen values of 10 PCs were shown to be larger than 1.0 but the 5 major PCs could account for 66% of the variance in the total variance of 39 GC peaks. The first and second PCs showed great importance for aroma quality and similarity or dissimilarity in profiles of extracted PCs showed a similar trend with quality differences evaluated by sensory tests. These results showed the importance of the harmonious balance of each aroma compound to create a preferable soy sauce aroma.

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The effect of organophosphorus fungicide, Kitazin P (IBP, S-benzyl diisopropyl phos-phorothiolate), on lipid biosynthesis of Pyricularia oryzae was investigated. Addition of IBP to the mycelial cells suspension of P. oryzae induced a striking decrease in incorporation of methionine-methyl-¹⁴C, S-adenosylmethionine-methyl-¹⁴C, and glycerol-1 ¹⁴C into phos-phatidylcholine, which is the most abundant phospholipid in P. oryzae, but incorporation of choline-methyl-¹⁴C into phosphatidylcholine and that of methionine-methyl-¹⁴C into simple lipids were not affected. Incorporation of methionine-methyl-¹⁴C into phosphatidylcholine is found to be directly proportional to mycelial cells growth of P. oryzae. Enzymes responsible for the biosynthesis from glycerol to phosphatidylcholine through Greenberg's pathway, except phospholipid N-methyltransferase, were not inhibited by IBP. IBP concentration required for 50% inhibition of phospholipid N-methyltransferase was 40 ppm. IBP had no effect on activities of glycerokinase, glycerophosphate acyltransferase, phosphatidic acid cytidyltransferase, phosphatidylserine synthetase, and phosphatidylserine decarboxylase, respectively. Therefore, the specific inhibition of conversion from phosphatidylethanolamine to phosphatidylcholine by the transmethylation of S-adenosylmethionine might be regarded as one of the modes of action of IBP.

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Caffeic acid (CA) was identified as an antibacterial substance in the digestive juice of silkworm larvae. Concentrations of CA in the digestive juice decreased from 460 ppm to 3 ppm as the starvation period of the larvae was prolonged from 1 hr to 12 hr. The specimens of digestive juice (ca. pH 10.0) containing 460 ppm and 222 ppm of CA had antibacterial activity against Streptococcus faecalis AD-4, a pathogenic intestinal bacterium affecting silkworm larvae, and an alkaline medium (pH 10.0) containing 500 ppm of authentic CA also exhibited antibacterial activity.
These findings suggest that CA plays an important role in the defense mechanism of silkworm larvae against the bacterial infection.

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Near ultraviolet irradiation and its significance to the photoresponsive system “myco-chrome” (involved in blue and near ultraviolet reversible photoreaction) in Alternaria tomato were studied. Near ultraviolet irradiation caused photoreduction of both P_B (blue absorbing pigment in mycochrome) and cytochrome c mediated through P_NUV (near ultraviolet absorbing pigment in mycochrome). Both P_NUV mediated photoreductions of P_B and cytochromec were larger under anaerobic conditions than aerobic conditions. Both photoreductions under aerobic conditions could be inhibited by superoxide dismutase; consequently, it is con-sidered that a superoxide anion was produced when P_NUV was exposed to near ultraviolet light under aerobic conditions which also reduced P_B and cytochrome c. Under anaerobic condi-tions, some photo-product resulting from the cooperation of P_NUV and near ultraviolet light (with the exception of a superoxide anion) may directly reduce either P_B or cytochrome c, since these photoreductions could not be inhibited by superoxide dismutase.
Furthermore, P_B and cytochrome c can be reduced by NADH, independent of light, if some crude enzyme fraction is added to that system. Reduced P_B can be easily oxidized by the addition of cytochrome c or the introduction of molecular oxygen. Thus, it is concluded that photoreactions, mediated through the mycochrome system, may be linked to electron flow.

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Growth of Bacillus subtilis AG169 that produced large amounts of xanthosine and guano-sine was inhibited by psicofuranine. When AG169 was mutated to resistance against psico-furanine, a mutant, GP-1, which yielded more guanosine was obtained. Psicofuranine did not inhibit growth of GP-l any more. The guanosine 5'-monophosphate (GMP) synthetase activities were then assayed. In GP-1, the specific activity decreased about half, the complete loss of repression by GMP was found, and the inhibition by GMP was slightly loosed, when compared with those of AG169.
Furthermore, as growth of GP-1 was strongly inhibited by decoyinine, decoyinine resistant mutants were derived from GP-1. Of these mutants, two strains, MG-1 and MG-4, were resistant to decoyinine completely and showed the exclusive accumulation of guanosine in high yields, i.e. 16.0 and 15.5g of guanosine per liter with weight yields of 20.0 and 19.4% of consumed sugar, respectively. GMP synthetase activity of MG-1 increased remarkably in comparison with that of GP-1 or AG169, and the inhibitions by GMP, psicofuranine and decoyinine were completely released in MG-1. Namely, the psicofuranine and decoyinine re-sistances seemed to cause mainly variations of GMP synthetase, and as results, the conversion of xanthosine 5'-monophosphate (XMP) to GMP proceeded more smoothly, and a larger amount of guanosine was accumulated.

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Production of solasodine in callus cultures of Solanum laciniatum Ait. was examined under several culture conditions. The steroidal alkaloid was produced more actively in rapidly proliferating callus tissues cultured on PN medium. The alkaloid concentration in the tissue was about 0.05% (dry weight basis) during the first 5 weeks' culture. The highest accumulation of the alkaloid per culture was obtained with 2, 4-D concentration in the medium at 1_??_2 ppm. It is noteworthy that the alkaloid production was not inhibited by such high concentration of 2, 4-D as up to 10 ppm in the medium. Supplementation of kinetin slightly increased the alkaloid production.

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L-Lysine could be determined satisfactorily with a new fungal enzyme, L-lysine α-oxidase (EC 1. 4. 3). The method consists of the oxidative deamination of L-lysine with L-lysine α-oxidase and the spectrophotometric determination of one of the reaction products: α-keto-ε- aminocaproate, its intramolecular dehydrated form, Δ¹-piperideine-2-carboxylate or hydrogen peroxide. The method on the basis of the color reaction of hydrogen peroxide formed from L-lysine with 4-aminoantipyrine and phenol in the presence of peroxidase was most sensitive and simple. The method could be used for the direct assay of L-lysine levels in serums from several animals without pretreatments.

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In order to investigate the active site of coronatine, the coronatine stereoisomers and analogs were synthesized by replacing the coronamic acid moiety with other amino compounds. The hypertrophy response of potato tubers was used for the bioassay of the compounds. A carboxyl group in coronamic acid was indispensable for the induction of activity. More-over, the configuration at α-carbon atom in the amino acid was closely related to increase in activity. Some alkyl groups of the amino acid also concerned with the activity.

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¹³C-NMR spectra of isoechinulins A, B and C, metabolites from Aspergillus Tuber, were fully assigned on the basis of chemical shifts and multiplicities and comparison with their analogues. Taking advantage of the symmetrical structure of the diketopiperazine ring, the stereochemistry of the trisubstituted carbon-carbon double bond in a dehydrotryptophyl moiety was determined as Z (cis) by measuring the coupling constants, J_-HC=C-CO_-, in the proton nondecoupled spectrum of isoechinulin B.

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The synthesis of 2-(6-methoxycarbonylhexyl)cyclopent-2-ene-I-one (5), a valuable inter-mediate in the synthesis of prostaglandins, is described starting from ethyl 3-oxoglutarate (1). The same reaction sequence also produces dihydrojasmone (12) and methyl dihydrojas-monate (13).

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