The effects of free fatty acids on the selectivity and thermal properties of starch samples incorporating free fatty acids were examined by DSC. An analysis of the free fatty acid values incorporated into cassava starch and potato starch shows that myristic acid was the highest and linoleic acid was the lowest, while the free fatty acid values of corn starch were significantly higher than those of the other starches. DSC measurements on corn starch show an initial peak and another peak in a higher-temperature region, this second peak differing according to the incorporated free fatty acid. It is thus considered that the state of the complex of each free fatty acid with amylose might be better understood by observing the respective DSC characteristics.

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In order to develop a new type of antioxidative compound which has both the phenolic and β-diketone moiety in the same molecule, we converted three known curcuminoids, curcumin (diferuloylmethane, U1), (4-hydroxy-3-methoxycinnamoyl)methane (U2), and bis-(4-hydroxycinnamoyl)methane (U3), which are the natural antioxidants of Curcuma longa L. (turmeric), to tetrahydrocurcuminoids (THU1, THU2, and THU3, respectively) by hydrogenation, and evaluated their antioxidative activity by using linoleic acid as the substrate in an ethanol/water system. Further, we used the rabbit erythrocyte membrane ghost and rat liver microsome as in vitro systems and determined the antioxidative activity of these curcuminoids. When we evaluated their antioxidative activity by these assays, it was found that THU1 had the strongest antioxidative activity among all curcuminoids in each assay system. THU1 has been reported to be one of the main metabolites of U1 in vivo [Holder et al., Xenobiotica, 8, 761-768 (1978)]. These results suggest that THU1 must play an important role in the antioxidative mechanism of U1 in vivo by converting U1 into THU1.

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Part of a 2.4-kb DNA fragment that encoded the amino-terminal 584 residues (65kDa) of an alkaline endoglucanase from Bacillus sp. KSM-635 (941 amino acid residues ; 105kDa) was spontaneously deleted during subcloning of the fragment. The remaining 1. 1-kb insert of the deleted plasmid encoded amino acids from Ala228 to Leu584 of the enzyme. However, Escherichia coli HB101 cells harboring this plasmid produced an active endoglucanase. After addition of a termination codon, TAA, immediately downstream of the codon for Leu584, the 1. 1-kb fragment was inserted into an expression vector, pHSP64. The resultant plasmid was introduced into Bacillus subtilis ISW1214 for extracellular production of the truncated endoglucanase. The enzyme was then purified to homogeneity from a culture of the recombinant B. subtilis cells. Amino-terminal sequencing of the enzyme showed that the enzyme consisted of 7 amino acid residues encoded by the vector and 357 amino acid residues encoded by the truncated gene, with a molecular mass of 40.2kDa. The purified enzyme was very active against carboxymethylcellulose and its pH and temperature profiles were almost identical to those of the enzyme produced by Bacillus sp. KSM-635.

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The ability of CuSO₄- and hypochlorite-oxidized LDL to promote cholesterol accumulation in macrophages was examined. Both CuSO₄- and hypochlorite-oxidized LDL were rapidly metabolized by mouse peritoneal macrophages to a level approximately 10 times that observed for native LDL and both modified lipoproteins increased the accumulation of unesterified cholesterol. However when each modified lipoprotein was incubated with macrophages for 40 h, only hypochlorite-oxidized LDL produced significant accumulation of cholesteryl esters, with levels approaching 85 μg/mg cell protein. This finding was verified by nile red staining. The cholesteryl ester content of cupric sulfate-modified LDL was found to be significantly decreased when compared to either native or hypochlorite-modified LDL promotes massive cholesteryl ester accumulation because the cholesteryl ester content of the LDL particle is preserved.

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β-Glucosidases (A, B, and C) have been isolated from soybean cotyledons. The isolated enzyme is a β-Glucosidase-C forming a single band on CM-Sephadex C-50 ion exchange chromatography, and on Butyl-Toyopearl 650C and Sephadex G-150 gel filtration. The homogeneity of the purified enzyme was proved by SDS-polyacrylamide gel electrophoresis and isoelectric focusing. The molecular weight was estimated to be 81, 000 and 36, 000 by HPLC gel filtration on TSKgel G3000SW_xL and SDS-polyacrylamide gel electrophoresis, respectively. The isoelectric point was estimated to be 6.68. The enzyme showed optimum activity at pH 4.5 and 45°C, and its pH range of action was 3.5-7.0. The enzyme was stable from pH 4.0to 6.0 at 5°C. The enzyme hydrolyzed the isoflavone glucosides, daidzin, and genistin, to yield daidzein and genistein .

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An extracellular polysaccharide elaborated by a new species of Beijerinckia indica, named TX-1, was composed of D-glucose, L-fucose, D-glycero-D-manno-heptose, and D-glucuronic acid in a molar ratio of 5.0 : 1.0 : 2.0 : 0.9, in addition to 16.2% of the acetyl group. Among the polysaccharides of the Beijerinckia species, the present polysaccharide might be the first acidic type having an L-fucose residue. A methylation analysis, Smith degradation study and fragmentation analysis show that this polysaccharide consisted of non-reducing terminal D-glucose, O-4 substituted D-glucose, O-2 substituted D-glycero-D-manno-heptose, O-4 substituted D-glucuronic acid, O-3 and O-4 substituted D-glucose, and O-3 substituted L-fucose residues. A D-glucuronic acid residue was linked to the O-3 position of the L-fucose residue by an α-glycosidic linkage. Most of the D-glucose residues in the backbone chain were substituted at the O-3 position, with the side chain having non-reducing terminal D-glucose residues. It is suggested by the reaction with Con A that the anomeric configuration of the terminal D-glucose residues was β.

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Lipase-surfactant complex (LSC) was prepared by mixing an aqueous solution of lipase (EC 3.1. 1.3)derived from Pseudomonas sp. and an ethanol solution of sorbitan mono-stearate. The LSC was used to catalyze the interesterification of triglyceride and fatty acid in a solvent system with hexane or in a solvent-free system. The optimum reaction temperature for the LSC was found to be 50°C. The LSC also had catalytic activity in a solvent-free system at 80-100°C. The optimum added water content at which the enzyme had maximum activity was found to be 100 mmol H₂O/(g-LSC) for various substrates and enzyme concentrations. This shows that the amount of water required depends on the amount of enzyme. Ethanol and diethylene glycol could be used as water substitutes, and the optimum hydroxyl group content was 100 mmol [OH] /(g-LSC).

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Exponentially growing Bacillus subtilis cells autolysed when exposed to cold shock treatment in minimal medium followed by incubation at 37°C. From characteristics of the lysis, it was suggested that the cold-shock-induced cell lysis resulted from the perturbation of membrane organization that is initiated by rapid changes in temperature, lipid phase transitions. For maximum lysis induction to occur, in addition to rapid cooling to 5°C or lower, retention at temperatures lower than 10°C for at least 20min is required. The cell sensitivity to the autolysis induction by cold shock was different between cells grown at 25°C and cells grown at 37°C. Analyses of the fatty acid composition and the phase transition temperature of membrane lipids suggested that the membrane fluidity may affect the autolysis induction. Experiments to discover the effects of cerulenin treatment and lipid addition on autolysis induction and the autolysin activity level support the hypothesis that membrane lipids are involved in cold-shock-induced cell autolysis.

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One of the esterified cerebroside in the epidermis of guinea pigs is shown to be (2S, 3R, 4E, 23'Z)-1-O-(β-D-glucopyranosyl)-N-(32'-linoleoyloxy-23'-dotriacontenoyl)-4-sphingenine by chemical and spectro-scopic studies.

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(2S, 3R, 4E, 23'Z)-1-O-(β-D-Glucopyranosyl)-N-(32'-linoleoyloxy-23'-dotriacontenoyl)-4-sphingenine (1), a component of the esterified cerebrosides in the epidermis of guinea pigs, was synthesized by selective N-acylation of (2S, 3R, 4E)-1-O-(β-D-glucopyranosyl)-4-sphingenine (18) with activated ω-linoleoyloxy fatty acid ester 17.

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The adsorption of β-lactoglobulin (β-Lg), one of the main constituents of fouling deposits in milk processing, onto the surface of stainless steel particles was studied under various conditions. The adsorption isotherm of β-Lg at 25°C was of the Langmuir type, and the plateau suggested that the surface was covered by a monolayer of β-Lg. The amount of β-Lg adsorbed steeply increased above 65°C. At 75°C, it increased almost linearly with the protein concentration in the bulk solution. Heating and chemical modification of the SH-group caused a much smaller amount of β-Lg to be adsorbed at 75°C. These findings indicate that the thermal aggregation of denatured β-Lg at the surface is important in the adsorption. More β-Lg was adsorbed at pH 4 than at pH 6.85. This suggests that the electrostatic interaction between β-Lg and the surface contributes to the adsorption behavior.

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We have identified the chemical structure of the lipid bioflocculant produced by Rhodococcus erythropolis S-1 strain. It was hydrolyzed with alkali and decomposed to sugar and fatty acid fractions. The sugar fraction was identified as a mixture of glucose and trehalose by HPLC and TLC analyses combined with acid and enzyme hydrolyses. The fatty acid fraction was identified as a mixture of many molecular classes of mycolic and mycoleic acids (2-alkyl-3-hydroxy long-chain fatty acids) of which the molecular masses were from 496 to 606 (C₃₂-C₄₀) with GC-MS analysis after methylesterification and trimethylsilylation. A gel permeation column chromatography study suggested that the lipid bioflocculant contained trehalose monomycolate, glucose monomycolate, and trehalose dimycolate. Furthermore, we showed that the lipid bioflocculant can be extracted directly from Rhodococcus erythropolis S-1 cells with organic solvents such as ethanol.

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The synthesis of (-)-decarestrictine J (1), a novel inhibitor of the cholesterol biosynthesis, is described. (-)-Epoxy alcohol 6, which was obtained by the Sharpless asymmetric epoxidation of trans-allylic alcohol 13, was converted to bromoacetoxy aldehyde 3 through a nine-step sequence. The samarium(II)iodide-promoted intramolecular Reformatsky reaction of 3 and subsequent oxidation afforded keto lactone 21 which, by treating with trimethylsilyl bromide, provided (-)-decarestrictine J (1).

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Four strains of Clostridium stercorarium, including three isolates with increased capacity to hydrolyze crystalline cellulose and assigned to the species, were characterized using recombinant DNA techniques, and compared to C. thermocellum. Their genomic DNA contained 3.0 megabases with 43% G+C. The genomic DNA fragment pattern was identified for the restriction endonucleases NotI and SfiI. Key enzymes of cellulolysis and hemicellulolysis were shown to be present in the genomic DNA of the new strains. A partial physical genomic map containing 6 genes involved in polysaccharide degradation for the type strain and 4 genes for the new isolates is presented. Strains of the species characteristically produced two extracellular cellulose binding proteins representing Avicelase I and II. The methods described allow us to ascribe the newly isolated thermophilic cellulolytic bacteria to the species C. stercorarium and are a basis for molecular biological work on that organism.

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A hyperthermophilic archaebacterium was isolated from a deep-sea black smoker chimney (depth, 760m) at the Minami-ensei Knoll (28°23'N, 127°38'E). The strain, designated DT1331, was a coccoid shaped bacterium about 0.5 to 1.0μm in diameter. The cells were surrounded by a cell envelope. The temperature for growth was between 55°C and 93°C with an optimum 80°C. The growth occurred from pH 4.5 to 8.5 and the optimum pH was 6.0. DT1331 required 1% to 5% NaCl for growth and cell Iysis was observed below 1% NaCl concentration. The strain was an anaerobic chemoorganotroph requiring elemental sulfur obligately. Organic substrates used included tryptone, peptone, soytone, casein, gelatin, and yeast extract. Under the optimal conditions, DT1331 had a generation time of 50min and could reach densities of about 1.5×10⁸ cells/ml. DT1331 was resistant to ampicillin, chloramphenicol, erythro-mycin, kanamycin, streptomycin, and tetracycline, which was one of the common characteristcs of archaebacteria. The G+C content of DT1331 was 52.3 mol%. Analysis of the 16S rRNA gene by restriction enzymes coincided with those of Thermococcus celer, indicating that this strain belonged to the genus Thermococcus.

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Emulsifying properties of bovine serum albumin (BSA) were compared between intact BSA (molecular mass of 66 kDa) and the domain I-truncated fragment (molecular mass of 45 kDa). The particle size considerably decreased with increasing both intact BSA and the fragment concentration. The intact BSA formed a more homogeneous emulsion and smaller particle distributions than the fragment at all protein concentrations. The relative amount of protein adsorbed at an oil-water interface was much less for intact BSA than for the fragment, and the surface concentration of intact BSA per unit surface area was also much less than that of the fragment, indicating that less protein is required to form a stable film for intact BSA than for the fragment. The particle size distribution in the fragment-stabilized emulsion became more homogeneous during storage time, while that in intact BSA-stabilized BSA had no significant change. These results strongly suggested that the domain I-truncated fragment with a higher hydrophobic value is more favorable toward the oil phase, while the highly charged domain I segment inhibits the droplet association, and consequently is important in stabilizing droplets dispersed in the emulsion.

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When embryogenic cell clusters prepared in a novel embryo-forming system were cultured in a standard liquid medium that contained methyljasmonate (MeJ), their development invariably proceeded to the torpedo stage but, thereafter, their morphological development to plantlets was suppressed to a considerable extent. Plantlets that occasionally regenerated in the presence of MeJ were very dwarfed. Secondary somatic embryogenesis was observed to occur at a frequency on the surface of embryos that remained at the torpedo stage and on dwarfed plantlets. Similar results were obtained with concanavalin A (Con A). These secondary embryos became developed normally into plantlets after transfer to a liquid medium without MeJ and Con A.

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Ribosomal proteins from 22 strains of 15 different species belong to the genus Arthrobacter were analyzed by an improved two-dimensional gel electrophoresis. Electrophoretograms of ribosomal proteins from 15 type strains had species-specific patterns. Similarity coefficients (S_AB values) of ribosomal proteins with mol. wt. of greater than about 20, 000, among strains of the same species (DNA relatedness values of more than 61%) were greater than 0. 85, but the S_AB values among strains of different species were less than 0. 60. The N-terminal amino acid sequences of the AL2 proteins, which migrated into similar positions in this method, from 5 type strains were shown to be highly homologous. Our results indicated that ribosomal proteins have been conserved within species during evolution and that the members of the genus Arthrobacter are phylogenetically homogeneous. Thus, ribosomal protein profiles by this method are a potential tool for strain identification.

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The effects of carnauba wax addition on the physical state of palm kernel oil-in-water emulsions were investigated. The oil-in-water emulsion (40wt% oil+60wt% aqueous phase) kept the liquid state at 25°C irrespective of the presence or absence of carnauba wax in the oil phase. The emulsion containing the wax transformed from the liquid state to the solid state by shearing after storage for 20h at 4°C, although the liquid-solid transition was not observed for the emulsion not containing the wax upon the same treatment. The viscoelasticity of the solid emulsions was demonstrated by small-deformation mechanical testing. Analysis of flow behavior of the emulsions showed that the change in physical properties of the emulsion containing the wax at 4°C was caused by the shearing at a low shear rate, around 50s_-1-100s_-1. According to the transition from the liquid state to the solid state of the emulsion containing the wax, the aggregation of oil droplets was found to occur to a large extent. The results of differential scanning calorimetry and surface pressure-surface area isotherms suggested that triglyceride molecules of palm kernel oil were more oriented at the oil-water interfaces in the emulsions after the wax addition. Based on these results, it is thought that carnauba wax is important in destabilization of palm kernel oil-in-water emulsions by modifying the physical state of the oil triglyceride molecules at the interfaces.

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A chromosome bisection method was constructed using yeast artificial chromosomes (YAC) and a GAL1-promoted site-specific recombination system. This method was applied to bisect chromosome IV into the left and right parts at the centromere region. The bisection occurred at frequencies of about 10% when the recombination site DNAs were integrated onto YAC and chromosome IV in the same direction, but were less than 10^-3 when they were in opposite directions. Reconstruction of the original chromosome IV from the bisected chromosomes was also induced by galactose at high frequencies. Loss of the left part chromosome was found at the frequencies of 0.9×10^-3 after hybrid cells between the chromosome-bisected strain and a normal haploid were subcultivated in a complete medium. The bisection and reconstruction of chromosome IV and deletion of the left part chromosome were demonstrated by electrophoretical karyotyping.

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In order to examine the hypothesis of pseudo-symmetry in the abscisic acid (ABA) molecule, (±)-7'-, 8'-, and 9'-methyl, and (±)-7'-, 8'-, and 9'-ethyl analogues of abscisic acid, whose pseudo-symmetry is decreased, were synthesized and, after optical resolution, tested for their inhibitory activity in four bioassays. The correlation of the decrease in the activity of (-)-7'- and 9'-alkyl-ABAs with that of (+)-9'- and 7'-alkyl-ABAs, respectively, seemed to agree with the hypothesis. The decrease in activity by alkylating C-8' of (+)-ABA was smaller than that by alkylating C-7' and C-9' of (+)-ABA, indicating that the activity was relatively unaffected by the bulky group at C-8' of (+)-ABA. Alkylation of C-8' and C-9', especially that of C-8', of (-)-ABA markedly reduced the activity. If the high activity of unnatural (-)-ABA is attributable to the pseudo-symmetry of the molecule, C-8' of (-)-ABA would occupy the space facing the re-face of C-2' in natural (+)-ABA. The low activity of (-)-8'-alkyl-ABA suggests the presence of a strict steric requirement of the binding sites to occupy the re-face of C-2' in (+)-ABA.

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We have cloned and characterized a genetic element (1187bp) that is responsible for the induction of thermotolerance as well as ompC expression in E. coli. This element (ISLtaq1) was isolated from Thermus aquaticus. DNA and protein data bases were searched with this element (ISLtaq1), which suggested it to be very similar to IS150 belonging to the IS3 family. ORF1, found on ISLtaq1, which encodes 100 amino acids (aa), had a DNA-binding motif : a helix-turn-helix and a leucine zipper. In fact, when the ORF1protein was overproduced in E. coli, thermotolerance as well as ompC expression was induced.

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Endogenous gibberellins in a parasitic plant, Aeginetia indica L., and its host, Miscanthus sinensis Andress (eulalia) were analyzed. Gibberellins of the early-non-hydroxylation pathway and their putative metabolites were identified as the major endogenous gibberellins from both types of A. indica parasitizing M. sinensis and parasitizing Oryza sativa L. (rice). Members of both the early-non- and early-13-hydroxylation pathways were detected in the host M. sinensis. Since the early-13-hydroxylation pathway has been reported to be the major pathway operating in vegetative tissues of O. sativa, these results suggest that A. indica can biosynthesize gibberellins independent of its hosts.

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Endogenous gibberellins in anthers of rice (Oryza sativa, cv. Nihonmasari (normal)) and in male sterile lines derived from Nihonmasari were quantitated by an immunoassay. The content of GA_4/7 and the dry weight of the anthers in the normal rice increased rapidly 1-2 days before heading. The content of gibberellins in the male sterile rice were roughly correlated with the pollen developmental stage characteristic of each line.

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Effects of high concentrations of 2, 4-dichlorophenoxyacetic acid on glutathione S-transferases, Puga, Pugb, Pugc, and Pugd, in pumpkin culture cells were investigated. When the culture cells were transferred from a standard medium containing 1ppm 2, 4-dichlorophenoxyacetic acid to the medium containing 40ppm, specific activity of GST in the cells increased four-fold. By two-dimensional electrophoresis, it was ascertained that the increase in specific activity of GST was due to specific elevation of levels of the GST proteins among soluble proteins from the culture cells. Each GST protein, however, had its own rate in its increase. Puga increased most intensively, so that the ratios of GST isozymes containing Puga increased markedly. Hence, Puga could be easily purified to homogeneity on SDS-PAGE from the culture cells treated with 40ppm 2, 4-dichlorophenoxyacetic acid. Differences between peptide patterns of Puga and Pugb digested partially with trypsin, and heterogeneity in cross-reactivities of GSTs with anti-Puga rabbit serum suggested that the primary structure of Puga might be different from those of the other pumpkin GSTs.

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A gene coding for a brain-derived neurotrophic factor (BDNF) obtained from rat BDNF cDNA was used to construct an expression plasmid, pTRSBDNF. It contained a BDNF gene that was fused, in frame, to a region encoding the β-lactamase signal peptide. The E. coli HB101 harboring pTRSBDNF produced 18mg/liter of mature protein. The E. coli cells produced a larger amount of BDNF than that of human nerve growth factor (hNGF), which was produced using the same expression system. The E. coli cells harboring pTRSBDNF were sonicated and centrifuged to obtain a supernatant and precipitate. The BDNF purified from the supernatant containing 20% of the total BDNF had high biological activity (EC ₅₀ of 30pg/ml) against neurons of chick dorsal root ganglia. On the other hand, the BDNF puritied from the precipitate had low biological activity (EC₅₀ of 2ng/ml) and incorrect disultide bonds.

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Glucoamylases from A spergillus niger and Rhizopus niveus catalyzed condensation of 2-deoxy-D-glucose (dGlc) to yield deoxy-glucooligosaccharides with polymerization degrees of 2-5. The enzymes also gave a small amount of products from 3-deoxy-D-glucose, but no products from 6-deoxy-D-glucose. A. niger α-glucosidase also catalyzed condensation of dGlc, while Torula and Saccharomyces α-glucosidases had low activity. α-1, 4-, 1, 6-, and 1, 3-linked deoxy-glucobioses were isolated and identified as the products of A. niger glucoamylase and A. niger α-glucosidase. In the reaction of the glucoamylase, 1, 4- and 1, 3-linked saccharides decreased with an increase of 1, 6-linked one. A. niger α-glucosidase produced α-1, 6-linked disaccharide predominantly during the whole course of the reaction.

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N-Methylhydantoin amidohydrolase, which catalyzes ATP-dependent hydrolysis of N-methylhydantoin to N-carbamoylsarcosine, was found to hydrolyze several nucleoside triphosphates to nucleoside diphosphates not only in the presence but also in the absence of amide substrates. Amide substrates, such as N-methylhydantoin and dihydrouracil, seem to be absolutely necessary for hydrolysis of ATP and dATP. However, N-methylhydantoin inhibited the hydrolysis of nucleoside triphosphates other than ATP and dATP. The kinetic data suggest that the presence of an amide substrate changed the affinity of the enzyme toward nucleoside triphosphates.

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The enantiomeric separation of SM-10661, a platelet activating factor receptor antagonist, was investigated by HPLC using ligand-exchange chiral stationary phases. The stereoisomers of SM-10661could all be separated by ligand-exchange HPLC with a Cu(II)N, S-dioctyl-D-penicillamine complex (Sumichiral OA-5000). The mechanism for the resolution includes the involvement of hydrophobic interactions between SM-10661 and Cu(II) D-penicillamine.

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An endo-β-1, 4-D-galactanase was purified 1735-fold from a commercial enzyme preparation of Aspergillus niger. The endo-galactanase was homogeneous by SDS-PAGE, having an appar-ent molecular weight of 32, 000. It specifically hydrolyzed β-1, 4-D-galactan, and is shown to be capable of releasing galactosyl oli-gomers and galactose from the soybean pectic polysaccharides.

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Six N-carbobenzozy amino acid derivatives of kojic acid were synthesized to improve the tyrosinase inhibitory activity of kojic acid. All derivatives showed stronger activities than kojic acid. Among them, the L-phenylalanine derivative was the strongest inhibitor and its IC₅₀ value was about 1/80 that for kojic acid. Theinhibition mechanism of these derivatives is considered to be a noncompetitive one similar to that of kojic acid.

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Koninginin E, a congener of previously isolated Koninginins A, B, and C, was isolated from Trichoderma koningii fermented on a shredded wheat medium. Selective supercritical fluid extraction was used in the rapid isolation of this otherwise intractable compound. Koninginin E inhibited the growth of etiolated wheat coleoptiles by 65% at 10^-3M.

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The catalytic domain (sGnT-I) of rat liver N-acetylglucosaminyl-transferase I (GnT-I) was expressed in Escherichia coli. Lysates from pETsGnT-I transformants contained a prominent protein species of 46kDa with which a significant GnT-I activity was associated. To purify the relevant enzyme, we constructed cDNAs encoding sGnT-ICH and sGnT-INH, which had six additional histi-dine residues as an affinity tag at the C-terminal and the N-terminal of sGnT-I, respectively, and introduced them into E. coli cells for expression. sGnT-INH was purified and its enzymatic properties were examined.

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A new metabolite of maleic hydrazide (MH ; 1, 2-dihydro-3, 6-pyridazinedione) was isolated from MH-treated tobacco (Nicotiana tabacum L. ) plants. The purified metabolite was identified as MH-N-β-D-glucoside by means of TLC, FAB-MS, ¹H-NMR, and ¹³C-NMR analyses.

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The insect antifeeding property of 25 limonoids isolated from Meliaceae plants, Okinawan and Chinese Melia azedarach and Chinese Melia toosendan, were tested by a conventional leaf disk method. The most potent were classified as azadirachtin-type C-seco limonoids and the next appear to be apo-euphol limonoids with a 14, 15-epoxide and a C-19/C-29 bridged acetal.

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Three cDNA clones encoding the 17. 5-kDa polypeptide of cucumber Photosystem I were isolated and sequenced. A cDNA insert of them was 812bp long and contained a long open reading frame that encoded a polypeptide with 217 amino acid residues. The deduced amino acid sequence of the cDNA was 77% and 71% identical to the amino acid sequences of psaL gene products from barley and spinach, respectively.

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The autoxidation of methyl linoleate was studied in emulsions prepared with a mixture of protein and highly concentrated saccharide by a gel emulsification method. As the concentration of dextrin increased, the autoxidation became progressively slower, and at the concentration of 60%, it was strongly suppressed. The effects of proteins and an emulsifier on the retardation of autoxidation decreased in the following order : sodium caseinate > egg albumin > Tween-60 > BSA. Dextrin increased the stability to autoxidation when compared with mono- and di-saccharides. The stability to autoxidation was increased with decreasing dextrose equivalent (DE) of dextrin. From these results, the autoxidation of methyl linoleate in the emulsion prepared with sodium caseinate and 60% dextrin (DE 8 or 11) by the gel emulsification method was strongly inhibited.

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A specific detection method for hydroxyproline by post-column derivatization with 7-chloro-4-nitrobenzo-2-oxa-1, 3-diazole was developed after chiral resolution by ligand-exchange chromatography. The addition of ethylenediaminetetraacetic acid to the reaction mixture was effective to achieve the post-column reaction. The calibration curve for trans-4-hydroxy-L-proline shows linearity from 7. 6pmol up to 7600pmol.

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Four pamamycin-607-degraded products-desdimethylaminopa-mamycin-607, a macrodiolide ring-opened compound, and two constitutent hydroxy acid-were prepared, and their aerial mycelium-inducing activity was measured. The hydroxy acid L part with a dimethylamino group was the principal component responsible for activity. The macrodiolide ring itself was dispensable, but only hydroxy acid L showed very weak activity.

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(S)-1, 3-Butanediol (BDO) oxidizing enzyme was purified from Candida parapsilosis IFO 1396, which could produce (R)-1, 3-BDO from the racemate. The purified enzyme was an NAD⁺ -dependent secondary alcohol dehydrogenase that oxidized (S)-1, 3-BDO to 4-hydroxy-2-butanone stereo-specifically.

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The extracellular lipase from Fusarium sp. YM-30 was purified by a procedure involving ultrafiltration, ammonium sulfate precipitation, and DEAE-Toyopearl 650M, CM-Toyopearl 650M, and Butyl-Toyopearl 650M column chromatographies. The purified lipase was homogeneous with 12kDa of molecular mass by SDS-PAGE, and had high specificities for mono- and di-acylglycerols, but low toward triacylglycerols. The enzyme had maximum activity at pH 7. 0 to 8. 0 and 37°C, and hydrolyzed digalactosyl diglyceride too.

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Dimethyl sulfide (DMS) was oxidized to dimethyl sulfoxide (DMSO) in cultures of five species of marine phytoplankton. Heat treatment (105°C, 5min) of such cultures rendered the oxidation more effective and the oxidation was stimulated by light. Tetrahydrothiophene was oxidized to tetramethylene sulfoxide by a heattreated cultures of Dunaliella sp. Dimethyl disulfide was reduced to methyl mercaptan only by the nonheated culture. Lyophilized cells of Dunaliella sp. and organic extracts of the cells and denaturalized chlorophyll a were also able to oxidize DMS.

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A marine bacterium that secretes a novel guluronate lyase that is heat-and denaturants-durable, has been isolated from the intestine contents of a red sea bream, Pagrus major. To characterize this marine bacterium, we attempted taxonomic study with respect to eleven characteristics used for the specification with an electron microscope photograph. The findings showed that the marine bacterium is a member of the genus Vibrio.

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Seeds of soybean [Glycine max (L. ) Merr. var. Bay] were irradiated with X-ray (21. 4kR), and the M2 generation was evaluated for palmitic acid content in the seed oil. The X-ray irradiation significantly increased the genetic variability of palmitic acid content in the oil of the Bay variety as compared with the control plants. Among the 2064 M2 plants tested, two mutants were selected in which the palmitic acid contents accounted for 5. 7 and 16. 6%, respectively, about two-fold lower and 1. 5-fold higher than that of the original variety. The mutants J3 and J10 always had lower and higher palmitic acid, respectively, under different environmental conditions in the M3 and M4 generations.

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The color of growting Bangah callus changed quickly from white to dark brown in MS medium containing 2, 4-D and kinetin at 1ppm each. The callus produced a large amount of total polyphenols, about 1.45-2.98% dry weight. The amounts of bound phenolic compounds were larger than the free compounds. Among the free phenolic compounds, cinnamic acid was the most plentiful and major components of insoluble-bound phenolic compounds were ferulic, cinnamic, and sinapic acids.

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Alternaria cassiae is a phytopathogen that has been isolated from diseased sicklepod. Ferricrocin and coprogen were isolated from a solid culture of A. cassiae and identified as phytotoxic compounds. The phytotoxicity of the two siderophores was compared by a leaf-wounding assay.

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A cysteine protease, phytolacain G, was purified to homogeneity from unripe fruits of pokeweed (Phytolacca americana). The apparent molecular mass of the purified phytolacain G was 25.5kDa. The caseinolytic activity of the enzyme was completely inhibited by a synthetic peptide containing an S-(3-nitro-2-pyridinesulfenyl)group (Npys). The inhibitory activity of this compound against phytolacain G resembled that for papain.

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The staphyloccocal toxin γ-hemolysin consists of two protein components, LukF and HγII. Staphylococcus aureus P83 was found to have five components, LukF, LukF-PV, LukM, LukS, and HγII for leukocidin orγ-hemolysin. HγII of S. aureus P83 was demonstrated to be a naturally-occurring analogous molecule of HγII [HγII(P83)], in which the 217th arginine residue was replaced by lysine. The HγII(P83) showed about 50% of the hemolytic activity of normal HγII in the presence of LukF.

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Novel analogs of the nonreducing-sugar subunit of bacterial lipid A, which were composed only of 3-hydroxytetradecanoic acid and its homologs, were synthesized. These analogs exhibited significant mitogenic activity.

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Using reverse transcription polymerase chain reaction (RT-PCR), we identified two cDNA fragments encoding aspartic proteinases (APs). The encoded proteins, pL4 and pL5, are similar in sequence to other plant APs including barley AP and cardoon flower AP (cyprosin). The identity was 58-76% with one another. Genomic Southern blot analysis suggested that the rice AP gene constitutes a multigene family.

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