We studied the mechanism of polymerization of proteins induced by storage with reducing sugars. Glucose alone did not polymerize acetylated lysozyme as a solid (75% relative humidity), but it did when there was free Lys. This indicated that a certain substance generated through a reaction between glucose and amino groups of proteins polymerized the proteins. The substance impaired Arg residues. The impaired Arg residues appeared in three peaks eluting just behind the Phe peak on amino acid analysis.
α-Dicarbonyl and α-hydroxycarbonyl compounds such as 2, 3-butanedione, glyoxal, methylglyoxal, dihydroxyacetone, glyceraldehyde, and glycolaldehyde polymerized both lysozyme and acetylated lysozyme, and impaired their Arg residues. However, the elution patterns of the impaired amino acid residues on amino acid analysis were different from that observed with glucose.
Glyoxal, methylglyoxal, and 2, 3-butanedione polymerized proteins to a notable extent even under the conditions used conventionally for chemical modification of Arg residues.

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E. coli 294 cells were transformed with a plasmid containing a hybrid gene in which the sequence encoding mature human epidermal growth factor (hEGF) was joined to the closed sequence encoding the signal peptide of E. coli alkaline phosphatase. During phosphate limitation these cells secreted hEGF to the periplasmic space.

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The heat-induced aggregation between ovalbumin and lysozyme was investigated under various conditions by measuring the development of turbidity. The result of sodium dodecylsulfatepolyacrylamide gel electrophoresis in the presence of 2-mercaptoethanol indicated that the obtained aggregate consisted of nearly the same amounts of ovalbumin and lysozyme. The heat-induced aggregation was inhibited by an increase of ionic strength. The effect of chemical modifications (succinylation and carboxymethylation) of the proteins on the heat-induced aggregation was examined to estimate the participation of specific amino acid residues in the aggregation process, the result indicating that the lysine and cysteine residues in the proteins were directly involved. From these results, it is suggested that the heat-induced aggregation between ovalbumin and lysozyme is due to an electrostatic attraction and sulfhydryl-disulfide interchange between the heatdenatured protein molecules.

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A new intracellular peptidase, which we call "D-peptidase S, " was purified from Nocardia orientalis IFO 12806 (ISP 5040). The purified enzyme was homogeneous on disc gel electrophoresis. The molecular weight and the isoelectric point were estimated to be 52, 000 and 4.9, respectively. The optimum pH for the hydrolysis of D-leucyl-D-leucine was 8.0 to 8.1, and the optimum temperature was 36°C. The purified enzyme usually hydrolyzed the peptide bonds preceding the hydrophobic D-amino acids of dipeptides. Tri- and tetra-peptides extending to the amino terminus of such peptides were also hydrolyzed. Therefore, the enzyme is a carboxylpeptidase-like peptidase specific to D-amino acid peptides. The Km values for D-leucyl-D-leucine and L-leucyl-D-leucine were 0.21 × 10^-3 and 0.44×10^-3 M, respectively. The activity was inhibited by several sulfhydryl reagents and two chelators, 8-hydroxyquinoline and o-phenanthroline.

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An acid Carboxypeptidase was highly purified and characterized from Aspergillus saitoi ATCC 14332. By disc gel electrophoresis at pH 9.4, SDS disc gel electrophoresis, and isoelectric focusing, the enzyme was essentially homogeneous. The molecular weight was 125, 000 by gel filtration and 72, 000 by SDS disc gel electrophoresis. The isoelectric point was 4.07. The enzyme acted as a carboxyamidase for cholecystokinin-tetrapeptide (CCK-tetrapeptide, Trp-Met-Asp-Phe-NH₂). The Km and K_cat values of the enzyme for Z-Glu-Tyr, angiotensin, and bradykinin at pH 3.1 and 30°C were 4.0mM and 106sec^-1, 0.05mM and 0.35sec^-1, and 0.04mm and 6.O sec^-1, respectively. An aqueous solution of the enzyme was freeze-dried retaining 98% of the enzyme activity. None of the activity was lost after preservation for 3 years at 4°C.

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Transglutaminase is a Ca²⁺ dependent enzyme that covalently polymerizes-proteins through the formation of ε-(γ-glutamyl)lysyl cross-links. We investigated the transglutaminase reaction in emulsions stabilized by protein. When emulsions prepared with proteins (α_sl-casein, and soybean 11S and 7S globulins) and soybean oil were incubated with transglutaminase, the emulsions turned into gels. Gel formation depended on the amount of transglutaminase and the pH. The results on SDS-polyacrylamide gel electrophoresis indicated that protein in the emulsions was polymerized by the action of transglutaminase. Gelation of the emulsions was attributed to the formation of ε-(γ-glutamyl)lysyl cross-links.

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Glutamate decarboxylase was purified from squash. The purification procedures included ammonium sulfate fractionation and successive gel filtration by Cellulofine GC-2000, Blue-Sepharose CL-6B and hydroxylapatite column chromatographies. The final preparation was homogeneous by polyacrylamide and SDS-polyacrylamide gel electrophoresis. The reaction product was identified as γ-aminobutyrate. The purified glutamate decarboxylase was stable at temperatures below 60°C and in a pH range of 5 to 7. The optimal temperature and pH were 60°C and 5.8, respectively. The Km value for glutamate was estimated to be 8.3mM.

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A bacterial strain, which was isolated from soil and identified as a Pseudomonas sp., grew on 2-naphthylamine-1-sulfonic acid (tobias acid), 1-naphthalenesulfonic acid and 2-naphthol-1-sulfonic acid as sole carbon sources. Ammonia and sulfonate were released from tobias acid with growth and accumulated in the cultural medium. Salicylic acid was also accumulated temporarily in the medium. The bacterium degraded gentisic acid, but not catechol. The following degradation pathway; tobias acid → 2-naphthol-1-sulfonic acid → l, 2-dihydroxynaphthalene → salicylic acid → gentisic acid is suggested for the degradation of tobias acid by this organism.

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Rice leaf slices stimulated with blast fungus hyphal component reduced nitroblue tetrazolium in a damped oscillatory profile with relaxing half wavelength in a medium containing glucose, when the respective rate of reduction was plotted against the function of time after the application of blast fungus hyphal component. In the presence of 110μM FAD and glucose, the wave number of the reduction profile increased 4- to 5-fold when compared to that in the absence of exogenous FAD. Exogenous FAD in the increasing concentration of 70 to 110μM, which was added in the presence of glucose, gave a positive heterotropic-like response upon the reduction of nitroblue tetrazolium with rice leaf slices which were press-injured and stimulated. Exogenous pyrroloquinoline quinone in the increasing concentration of 10^-3 to 10^-1μM, which was added in the presence of glucose, gave an inhibition upon the reduction. From sediment of the homogenate of stimulated rice leaf slices, the nitroblue tetrazolium reducing redox-enzyme system was solubilized by Triton X-100 and was electrophoretically isolated in a sharp blue band on a polyacrylamide slab gel containing Triton X-100, when the electrophoresed gel was stained by nitroblue tetrazolium or Coomassie brilliant blue. In the solubilized solution, the presence of b-type cytochrome was observed by the oxidationreduction difference spectrum.

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Ten bacteria capable of using 1, 12-diaminododecane (DAD) as a sole carbon and energy source were isolated from soil samples.
Four strains (K95, K55, K24, 110-2) were identified as Pseudomonas, four (DAD2-3, 10-23-A, 10-23-B, K61) as Nocardia and two (DAD2-1, 1994) as Corynebacterium on the basis of their taxonomic characteristics.
Metabolic products such as 12-aminododecanoic acid, 12-hydroxydodecanoic acid, 1, 10-decanedicarboxylic acid, sebacic acid, suberic acid, adipic acid and α-ketoglutaric acid were found in the culture broths of various bacteria. The yields of 12-aminododecanoic acid and 12-hydroxydodecanoic acid from DAD were as high as 55% and 20%, respectively.
An amine dehydrogenase was found in cell-free extracts of Pseudomonas K95 and amine oxidases were detected in cell-free extracts of Nocardia 10-23-A.
A biodegradation pathway for DAD is proposed.

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The cell-free extract of Pseudomonas K95 gwown on 1, 12-diaminododecane (DAD) could oxidize all tested alkyl diamines, from C₄ to C₁₂. The cell-free extract contained an amine dehydrogenase. The amine dehydrogenase was purified 1700-fold to homogeneity from Pseudomonas K95 grown on DAD as the sole carbon source. The molecular weight of the enzyme was found to be 56, 000, on gel filtration, and 47, 000, on sodium dodecyl sulfate gel electrophoresis; no evidence was obtained for subunits. The enzyme is able to utilize only phenazine methosulphate as an electron acceptor. The enzyme is markedly nonspecific, readily oxidizing both short and long chain primary monoamines and diamines, polyamines, L-noradrenaline, histamine, benzylamine and di-n-hexylamine. The enzyme was inhibited by the carbonyl reagents, semicarbazide and isoniazid. The optimum pH for the oxidation of DAD was 7.0 and that for 12-aminododecanoic acid (ADA) was 8.0. The Km value for DAD at pH 7.0 was 3 μM and that for ADA was 33 μM. The difference in the Km values probably explains the observed accumulation of ADA during the growth of Pseudomonas K95 on DAD.

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Acinetobacter calcoaceticus, which is unable to grow in the presence of glucose because it lacks hexokinase and gluconokinase activities, grows well in the presence of permeable intermediates of the tricarboxylic acid cycle. However, addition of glucose led to increased rates of growth with other carbon sources, although it is unable to grow in the presence of glucose as the sole carbon source. This species possesses pyrrolo-quinoline quinone-dependent glucose dehydrogenase on the outside of the membrane, and through coupling with this emzyme, ATP was synthesized in the presence of glucose. The newly biosynthesized ATP with the addition of glucose led to increases in the initial rate of the active transport system and the growth rate of the cells. The supplemental energy due to glucose oxidation may be obtained through a cytochrome-linked reaction with the glucose dehydrogenase.

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DNA strand scission due to aminosugars and their derivatives in plasmid pBR322 was investigated through agarose gel electrophoresis. D-Glucosamine and its related aminosugars primarily caused single-strand scission of ccc-DNA to form oc-DNA in a time- and temperaturedependent manner. The degree of reaction was also related to the concentration of aminosugars. D-Glucosamine-6-phosphate was the most active among the compounds tested, and converted oc-DNA into linear-DNA and further fragmented DNA. The reaction was stimulated by Cu²⁺ and inhibited by catalase, superoxide dismutase, and some radical scavengers. The DNA strandscissoring activities of aminosugars were related to their nitroblue tetrazolium-reducing activities. These results support a hypothetic mechanism in which some free radicals, generated during autoxidation of aminosugars in aqueous solution, are involved in DNA strand scission.

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The properties of the intraspecific hybrids obtained by protoplast fusion of (+) and (-) mating type strains of Mucor pusillus producing the milk-clotting protease were studied, especially as to their mating types and enzyme productivities. All of the prototrophic hybrid strains obtained from the (+) ade/hyp+(-) cho fusion and three adenine-requiring segregants obtained on serial subcultivation formed zygospores autonomously. In the case of the (-) cho+(-)met fusion, most of the prototrophic hybrids had the (-) mating type, however, two of the 25 non-sectored hybrids were found to be homothallic and formed zygospores autonomously. Although the enzyme productivities of the intraspecific hybrids were lower than that of Mucor miehei, which is closely related to Mucor pusillus, the hybrids showed distinctly higher productivity than the parental Mucor pusillus strains.

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New and efficient syntheses of (±)-ambrox (1a), (±)-ambra oxide (2a) and their Stereoisomers (1b, 2b-c), amber-like odorous compounds, are described. Starting from dihydro β- and α-ionone (5, 12), these substances were obtained in only a few steps via stereoselective acid-catalized cyclization of monocyclodienoic acid (7a-b, 11a-b, 15a).

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The oxygen radical species responsible for the inactivation of phages by ascorbic acid was investigated, using four phages of different nucleic acid types.
A scavenger for the superoxide anion radical (O₂^-) and scavengers for the hydroxyl radical (OH•) markedly prevented the inactivation of phages by ascorbic acid. Quenchers for singlet oxygen (¹O₂ slightly prevented the inactivation. Catalase fully prevented the inactivation, whereas superoxide dismutase only partially prevented it. Phages were markedly inactivated in an OH•- generating system, but not in an O₂^--generating system or an ¹O₂-generating system.
These results, taken together, indicate that OH• is the major reactive species and that it is directly responsible for the inactivation of phages by ascorbic acid.

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The nutritional factors affecting the activity of liver nicotinamide methyltransferase (EC 2.1.1.1) and urinary excretion of N¹-methylnicotinamide in rats were investigated. Nicotinamide methyltransferase was found mainly in liver and a little activity was detected in kidney. This enzyme activity was elevated by the feeding of an excess nicotinamide-containing diet (2.0-fold), a thiaminfree diet (3.3-fold), a high protein diet (1.6-fold), and a fat-free diet (1.9-fold) compared with the activity of each control group. On the other hand, urinary excretion of N¹-methylnicotinamide was also increased by the feeding of the excess nicotinamide-containing diet (182-fold), the thiamin-free diet (1.6-fold), and the high protein diet (2.8-fold), while its excretion was decreased by the fat-free diet (0.35-fold). Therefore, urinary excretion of N¹-methylnicotinamide could be controlled by some unknown factors, possibly the nicotinamide concentration, rather than by the activity of nicotinamide methyltransferase.

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Ceramide aminoethylphosphonate was isolated from the shellfish, AGEMAKI, Sinonovacula constricta. The compound was purified through a combination of mild alkaline hydrolysis of the total lipids, QAE-Sephadex-A25 column chromatography and two dimensional thin layer chromatography. The infrared spectrum showed an absorption band at 1180cm^-1 due to a C-P bond, and was essentially identical with that of the standard ceramide aminoethylphosphonate. Upon hydrolysis of the substance with a strong acid, neither a change in its chromatographic behavior nor liberation of inorganic phosphate was observed. The stability of the compound as to acid hydrolysis suggested the presence of a C-P bond. On comparison with the synthetic compound, the aqueous hydrolysis product was found to behave like 2-aminoethylphosphonic acid on thin layer chromatography.
The predominant fatty acids were palmitic acid and stearic acid. The results obtained suggest that a person may ingest and absorb 2-aminoethylphosphonic acid, through the food chain, on the consumption of edible shellfish.

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A part of the rDNA plasmid of Zygosaccharomyces bailii IFO 0488 has been cloned. The cloned sequence contained 18S, 25S and probably 5S rRNA sequences. The cloned rDNA of Z. bailii hybridized with rRNAs of Saccharomyces cerevisiae. On using this rDNA sequence as a probe, we found that every sample of closed circular DNA from yeasts tested contained this kind of DNA plasmid. The rDNA unit from Z. bailii carried an ARS that functioned in S. cerevisiae and Z. rouxii. However, the sequence required for the ARS function differed depending on the host. When a vector based on the rDNA of Z. bailii was introduced into S. cerevisiae, it was integrated predominantly into the RDNl locus. These facts imply that the rDNA plasmid is practically useful for contracting vectors suitable for intergeneric gene transfer among yeasts.

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Pseudomonas cruciviae S93B1 produced three HOPDA reducing enzymes (I, II, III), found by chromatography on DEAE-Sepharose CL-6B. The purified HOPDA reducing enzyme III was homogeneous on polyacrylamide gel and has a mol. wt. of about 170, 000 by Sephadex G-200. The reducing enzyme III produced 2, 6-dioxo-6-phenylhexanoic acid from HOPDA. NADPH was an essential cofactor for HOPDA reducing enzyme III. The enzyme was stable between pH 5 and 7. The ring-fission products from biphenyl-2, 3-diol, 3-isopropylcatechol, 3-methylcatechol and the methyl ester of HOPDA were substrates for the reducing enzymes I, II and III. The ring-fission products from 3-methoxycatechol and catechol served as substrates for reducing enzymes I and II. The methyl ester of HOPDA was reduced by reducing enzyme III to 2-methoxy-6-oxo-6-phenylhexa-2-enoic acid methyl ester.

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Cell-walls prepared from Rhizoctonia solani, cultured with or without validamycin (VM), and fractionated into four fractions (F-I, II, III and IV) by treatment with an alkali or an acid. A quantitative decrease in only cell-wall fraction III (F-III, glycan). i.e., not the other fractions (F-I, F-II and F-IV), due to VM inhibition was observed. The component sugars of individual fractions were investigated by means of acid hydrolysis, methylation analysis, paper chromatography or Smith degradation.
From the results, fractions I, II and IV were each assumed to be proteoglycan, free glucose containing oligosaccharides or a chitin, respectively, while fraction III was assumed to be (1→3)-linked glucomannan containing small amounts of pentoses (ribose, arabinose and xylose). With the VM inhibition, the sugar components of the individual fractions, I, II, III and IV, were little affected, but in fraction III the amount of (1→3)-linked glucose or xylose increased, whereas the amount of (1→3)-linked mannose or -arabinose decreased. Thus, a change in the molar ratio of glucose to mannose was the major change observed in the component sugars of cell-wall fraction III from a VM-inhibited R. solani culture.

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N-Benzoyl-L-alanine amidohydrolase was purified from a cell-free extract of Corynebacterium equi H-7 which was grown in a medium containing hippuric acid as the sole carbon source. The purified enzyme was homogeneous on polyacrylamide gel electrophoresis and SDS-polyacrylamide gel electrophoresis. The molecular weight was 230, 000 and the enzyme consisted of six subunits, identical in molecular weight (approximately 40, 000). The isoelectric point of the enzyme was pH 4.6. The optimum pH of the enzyme reaction was 8.0 and the enzyme was stable from pH 7.0 to 8.0. The enzyme hydrolyzed N-benzoyl-L-alanine, N-benzoylglycine, and N-benzoyl-L-aminobutyric acid. The Km values for these substrates were 4.3mM, 6.7mM, and 4.3mM, respectively. The enzyme was activated by Co²⁺.

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The substrate specificities and reaction conditions for the microbial oxidation of higher alcohols in isooctane were investigated using Rhodococcus equi cells grown on n-tetradecane as the sole carbon source. Primary alcohols, C₄-C₁₄ (even numbers), were oxidized to the corresponding carboxylic acids, with which the substrate alcohols further combined to form esters, and various kinds of secondary decanols were oxidized to the corresponding ketones, suggesting that the substrate specificities of R. equi were not so restricted in isooctane. As to the reaction conditions, water was positively required for the oxidation of hjgher alcohols such as 1-tetradecanol in organic solvents such as isooctane, although the amount of water required represented only a small portion of the reaction mixture. On the other hand, ester formation took place in isooctane practically free from water, and the rates of ester formation from 1-tetradecanol and tetradecanoic acid by dried cells increased with an increase in temperature up to 70°C in isooctane, while ester formation hardly occurred at 70°C when intact cells were used in place of dried cells. It was thus suggested that microbial ester formation is less susceptible to thermal inactivation in the absence of water than in its presence.

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The nifA gene in the 2.9-Kb SalI fragment from the nif gene cluster of Klebsiella oxytoca NG13, an associative nitrogen fixer in the rice rhizosphere, was cloned into the SalI site of pACYC184 to obtain pNOW7A (6.8Kb, Cm^r, nifA⁺), in which the nifA gene was expressed from the constitutive Tc^r gene promoter. A recombinant plasmid, pNT11 (15.7Kb, Su^r, nifA⁺), was constructed by ligating pNOW7A and RSF1010 at single EcoRI sites. Constitutive expression of the nifA gene on pNOW7A in K. pneumoniae UNF714 nifA^- and K. oxytoca NG13 caused derepression of the nitrogenase activity in the presence of NH₄⁺. pNT11 induced nitrogenase activity in Azospirillum lipoferum in the presence of NH₄⁺ to the level of 0.7% of that in the absence ofNH₄⁺.

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The effects of dietary protein on intestinal 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase were studied in rats. When the rats' diet was changed from a commercial non-purified diet to a purified diet containing either soybean protein or casein as a protein source, the reductase activity in the jejunum increased progressively while that in the ileum decreased. The extent of the change in the jejunal activity was prominent in rats fed soybean protein. When rats were given a purified diet containing casein for 8 days then a purified diet containing soybean protein, the enzyme activity increased progressively both in the jejunum and ileum. The protein-dependent change became apparent within 1 to 3 days. Among the various animal (sardine and lactalbumin) and vegetable (soybean and wheat gluten) proteins tested, soybean protein was the one that had a specific effect on the intestinal reductase. The contents of mucosal cholesterol was essentially the same except for a slight higher level for the ileum from rats fed lactalbumin. The concentration of serum cholesterol were lower in rats fed vegetable proteins, while the hepatic cholesterol-lowering action of dietary protein was evident only with soybean protein.

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Cross-linked poly(N-benzyl-4-vinylpyridinium bromide), an insoluble pyridinium-type polymer, was found to adsorb bacteriophage T4. The system reached equilibrium during 2 hr at 25°C. The Freundlich isotherm plot gave log X=0.13 log C_e+5.6, where X is the amount of adsorbed T4 phage per unit weight of the polymer (PFU/mg), and C_e is the equilibrium concentration of free T4 phage in solution (PFU/ml). Adsorption was greatly stronger than that by soils or minerals. The T4 phage adsorbed by the polymer was still bacteriolytic.

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Synthetic studies on the derivatives of 5-O-β-D-galactofuranosyl-D-galactofuranose, which is the carbohydrate moiety of helminthosporoside (HS-toxin) from Helminthosporium sacchari, are described.

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A novel enzyme, which was named N^α-benzyloxycarbonyl amino acid urethane hydrolase II, was purified from a cell-free extract of Lactobacillus fermenti 36 ATCC 9338. The enzyme catalyzed the stoichiometric hydrolysis of N^α-benzyloxycarbonyl arginine to form benzyl alcohol and arginine. The enzyme was purified 106-fold with an activity yield of 3%. The purified enzyme was homogeneous by disc gel electrophoresis. The molecular weight of the native enzyme is about 200, 000 by gel nitration, and a molecular weight of 27, 000 was found for the reduced and denaturated enzyme by gel electrophoresis in sodium dodecyl sulfate. The isoelectric point of the enzyme was 5.0, it was inhibited by disodium ethylenediamine tetraacetate and p-chloromercuribenzoate, and the. presence of a divalent cation, i.e. Co²⁺, is essential for its activity.

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NADP⁺-linked isocitrate dehydrogenase (EC 1.1.1.42) was purified to homogeneity from a crude extract of acetate-grown Paecilomyces varioti AHU 9417 with high malic acid productivity, by ammonium sulfate fractionation and column chromatography on DEAE-Sepharose CL-6B, Matrex Blue-A and Agarose-hexane-NADP⁺. The molecular weight of the enzyme was 99, 000 and the subunit molecular weight was 51, 000. The optimum pH for the reaction was 8.4. The Km values for threo-Ds-isocitrate and NADP⁺ were calculated to be 12 μM and 4.4 μM, respectively. Adenine nucleotides had little effect on enzyme activity. Of metabolic intermediates related to the TCA and glyoxylate cycles, α-ketoglutarate inhibited the activity for isocitrate competitively and oxalacetate, non-competitively. Addition of other organic acids such as succinate, fumarate, and pyruvate brought no or slight inhibition at the concentration of 1 mM. However, when oxalacetate and glyoxylate were added simultaneously, the enzyme activity was strongly inhibited at the level of a few μM of each compound. From these observations and previous knowledge of isocitrate lyase, the regulation of the TCA cycle and the glyoxylate cycle is discussed.

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The 1, 3-diacylglycerol and 1, 2-diacylglycerol types of multiacylglycerol were first isolated from the stigmas of Nicotiana tabacum (Bright Yellow). These multiacylglycerols were separated into more than five spots, such as tri-, tetra-, penta-, hexa- and heptaacylglycerol. The main hydroxy fatty acids of these two types of multiacylglycerol were C_18:1-ω-hydroxy and C_18:2-ω-hydroxy fatty acids. The terminal OH groups of these fatty acids were all esterified with other fatty acids

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(±)-Methyl phaseates were synthesized from (±)-4-(6'-acetoxymethyl-2', 6'-dimethyl-1'-cyclohexen-1'-yl)-but-3-en-2-one (20), which was prepared from a useful terpenoid building block, (±)-2-hydroxymethyl-2, 6-dimethyl-1-cyclohexanone (11a and 11b). Photooxidation of the cyclohexadiene intermediate (22), followed by alkaline hydrolysis and methylation, gave four stereoisomers of (±)-methyl phaseates: (2Z, 4E)-cis form (2), (2Z, 4E)-cis form (24), (2Z, 4E)-trans form (25) and (2E, 4E)-trans form (26).

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Two host-selective pathotoxins, ACTG-toxins A and B, and four related but less active toxins, C, D, E, and F, were isolated from the culture broth of Alternaria citri, a fungus that produces brown spot disease of Dancy tangerine (Citrus reticulata) and other mandarin cultivars. The basic common structural features of these toxins were the presence of a six-membered group bonded, via a methylene group, to a five-membered ring having an alkenyl substituent (Fig. 1). For Toxins A, B, C and F, the six-membered ring had an enolizable β-diketo group. For Toxin C, the five-membered ring was a tetrahydrofuran group. For Toxins D and E, an additional dihydropyran ring was formed by dehydration between a tertiary hydroxyl on the cyclopentene ring and an enolic hydroxyl group on the cyclohexane ring, and also the presence of a terminal hydroxymethyl group on the alkenyl substituent, instead of the methyl groups in Toxins A, B and C. In Toxin F, the terminal group was a formyl.

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Sixteen triterpenoid glycosides, named S13 to S25, S37, S38 and S40, were isolated from the root of Bupleurum polyclonum Y. Li et S. L. Pan, and their structures were determined from NMR spectral analyses. Among them, S24, S37 and S38 were found to be new substances, their structures being established as 30-β-D-glucopyranosyl 30-hydroxysaikosaponin-b₂, 2''-O-acetylsaikosaponin-b₂ and 3''-O-acetylsaikosaponin-b₂, respectively.

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From the roots of Bupleurum kunmingense, nine new saponins, named S26-S29, S31-S34 and S36, were isolated and their structures were determined based on chemical and NMR spectroscopic analysis as follows: S26, 3'', 4''-di-O-acetylsaikosaponin-d; S27, 3'', 4''-di-O-acetylsaikosaponin-b₄; S28, 3'', 6''-di-O-acetylsaikosaponin-d; S29, 3'', 4''-di-O-acetylsaikosaponina; S31, 3'', 6''-di-O-acetylsaikosaponin-a; S32, 2'', 3''-di-O-acetylsaikosaponin-a; S33, 4'', 6''-di-O-acetylsaikosaponin-d; S34, 3''-O-acetylsaikosaponin-e; and S36, 2'', 3''-di-O-acetylsaikosaponin-d.

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(Z)-3-Dodecen-12-olide 1 and (5Z, 13S)5-tetradecen-13-olide 2, the macrolide pheromones of the flat grain beetle, were synthesized by employing the acetylene zipper reaction in the key steps.

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Microorganisms capable of hydrolyzing raw starch were isolated widely from various sources, and the amylase productivity of each strain was examined on plate culturing. Of the fungi and actinomycetes tested, 78 strains were subjected to subsequent testing for amylase production, and 5 strains were selected as active amylase producers. Among them, Corticium rolfsii AHU 9627 produced the most active raw starch saccharifying enzyme. The crude enzyme (100IU/g starch) almost completely hydrolyzed a 20% (w/v) suspension of raw corn starch at pH 4.0 and 40°C in 48 hr. The ratio of raw starch saccharifying activity to gelatinized starch saccharifying activity (RDA) of this enzyme was higher than 30% when corn starch was used as the substrate. We have never heard of such a strong enzyme as to RDA, and the enzyme was considered useful for the effective saccharification of starch without cooking.

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