An enzymatic-HPLC method to analyze the serum concentration of D-3-hydroxybutyric acid was developed. A deproteinized sample of rat serum was treated with 3-hydroxybutyrate dehydrogenase in the presence of NAD, and was analyzed by reversed-phase HPLC to separate and quantify NADH formed by the enzyme reaction, monitoring OD at 340 nm. Standard samples containing varying amounts of D-3-hydroxybutyric acid (0–10 nmol in 50 μl) were treated with 3-hydroxybutyrate dehydrogenase and analyzed by HPLC (the injected amount was 0–2.7 nmol of D-3-hydroxybutuyric acid), resulting in the peak area increasing proportionally with the injected amount. The method proved sensitive enough for as little as 0.2–2 nmol D-3-hydroxybutyric acid in 50 μl to be accurately analyzed. Only 10–20 μl of the rat serum protein-free extract is therefore required to obtain a reliable value. The values obtained with this method are identical to those observed by the conventional enzyme-spectrophotometric method. This method can be easily conducted in many laboratories because it is highly sensitive and only requires HPLC apparatus equipped with a UV meter.

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The syntheses of racemic and optically active pseudodeflectusin and ustusorane C are described. The ¹H- and ¹³C-NMR data for our synthetic pseudodeflectusin and ustusorane C were identical to those of the corresponding natural products. We also synthesized the proposed structure of aspergione A and B whose ¹H- and ¹³C-NMR data were identical to those of ustusorane C and pseudodeflectusin. The ¹H- and ¹³C-NMR spectra of our synthetic aspergione A and B were different from those of the natural compounds. Our results confirm that aspergione A and B are in fact ustusorane C and pseudodeflectusin, respectively.

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Improved syntheses of optically pure (−)- and (+)-morinol C, and (−)- and (+)-morinol D were achieved by employing the Mizoroki-Heck reaction to construct the cinnamyl moiety. The protective group of the alkene substrate affected the yield of this key reaction. The reaction with a combination of the acetate-protected olefin and 4-methoxyphenylboronic acid gave the best result producing morinol C and D. All stereoisomers of morinol C and D showed cytotoxic activity, with (R,R)-morinol C showing the highest antibacterial activity.

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The root parasitic plant, Striga hermonthica, constrains the production of several agronomically important poaceous crops in the arid and semiarid tropical regions of Sub-Saharan Africa. The parasite is incompatible with the model legume, Lotus japonicus. Studies at the molecular and metabolic levels have revealed that expression of the genes involved in the biosynthesis of vestitol, a legume-specific phytoalexin, was highly up-regulated in L. japonicus roots challenged with S. hermonthica. High-performance liquid chromatography and mass spectroscopy confirmed the presence of vestitol in the exudate released from L. japonicus roots inoculated with S. hermonthica seedlings. Fluorescence, similar to that emitted by authentic vestitol, was displayed on the surface of L. japonicus roots to which successful attachment of S. hermonthica had been achieved. Vestitol exerted a limited inhibitory effect on S. hermonthica germination, but it significantly inhibited seedling growth. These results indicate that vestitol biosynthesis in L. japonicus was induced by S. hermonthica attachment and that vestitol contributed, at least in part, to the host’s defence mechanism and acted as a chemical barrier against the intrusion of the parasite.

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A methanolic extract of Agrimonia eupatoria (Rosaceae) significantly attenuated glutamate-induced oxidative stress in HT22 hippocampal cells. A new flavonoid, characterized as kaempferol 3-O-β-D-(2″-O-acetyl-6″-(E)-p-coumaroyl)-glucopyranoside (2″-acetyl-tiliroside (1), was isolated from the methanolic extract of A. eupatoria stems together with nine known flavonoids. Compounds 4, 7, 8 and 9 all showed a neuroprotective effect on glutamate-induced toxicity in HT22 cells.

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Previously, we found that expression by translational fusion of the polyhedrin (Polh)-green fluorescence protein (GFP) led to the formation of granular structures, and that these fluorescent granules were easily precipitated by high-speed centrifugation. Here, we developed an easy, fast, mass purification system using this baculovirus expression system (BES). An enhanced GFP (EGFP) fused with the Polh gene at the N-terminus, including a linker and enterokinase (EK) site between Polh and EGFP, was expressed in Sf9 cells. The cells infected by AcPolhEKA-EGFP produced fluorescent granules. The EGFP fusion protein was purified from granule-containing cells in three steps: cell harvest, sonication, and EK digestion. Through final enterokinase digestion, EGFP presented mainly in the supernatant, and this supernatant fraction also showed a pure EGFP band. These results suggest that a combined procedure of Polh fusion expression and enterokinase digestion can be used for rapid and easy purification of other proteins.

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sHSP20.8 and sHSP19.9 are silkworm small-heat shock proteins (sHSPs) comprising a number of polypeptides of molecular sizes of several tens of kilodaltons as subunits. The structural properties of sHSPs were investigated. sHSP19.9 was found to be aggregated by itself during incubation at 60 °C. Aggregation was suppressed in the presence of dithiothreitol and at high ionic strength. In contrast, sHSP20.8 was not aggregated. Aggregation of sHSP19.9 was partially suppressed by sHSP20.8 and in the presence of catalase as a target protein. Based on changes in small-angle X-ray scattering, it is possible that the molecular size of sHSP19.9 is larger than that of sHSP20.8, and that their molecular sizes increase with increasing temperature in a reversible, biphasic manner. sHSPs did not protect catalase from thermal inactivation, but protected it from precipitation by forming a soluble complex. sHSP20.8 and sHSP19.9 with dithiothreitol were stable against lyophilization, autoclaving at 120 °C, and boiling.

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L-Amino acid ligase synthesizes various peptides from unprotected L-amino acids in an ATP-dependent manner. Known L-amino acid ligases catalyze only dipeptide synthesis, but recently we found that RizB of Bacillus subtilis NBRC 3134 catalyzes oligopeptide synthesis. In the present study, we searched for new members of the L-amino acid ligase group that catalyze oligopeptide synthesis. Several hypothetical proteins possessing the ATP-grasp motif were selected by in silico analysis. These recombinant proteins were assayed for L-amino acid ligase activity. We obtained five L-amino acid ligases showing oligopeptide synthesis activities. These proteins showed low similarity in amino acid sequence, but commonly used branched-chain amino acids, such as RizB, as substrates. Furthermore, the spr0969 protein of Streptococcus pneumoniae synthesized longer peptides than those synthesized by RizB, and the BAD_1200 protein of Bifidobacterium adolescentis showed higher activity toward aromatic amino acids than toward branched-chain ones. We also examined some of their characteristics.

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Swertia mussotii Franch has anti-hepatitis activity and contains a high level of iridoid monoterpenoids. The cytochrome P450 monooxygenase (CYP) geraniol 10-hydroxylase (G10H) is thought to play an important role in iridoid monoterpenoid and indole alkaloid biosynthesis. Here we report the isolation of a full-length cDNA clone of S. mussotii G10H (SmG10H). The predicted gene product was a 496 residue protein designated CYP76B10, the sequence of which was highly similar to that of the CYP76 family, particularly to Catharanthus roseus G10H (80.2% homology). SmG10H transcripts were much more abundant in the leaves than in either the root or the stem, and were derived from a single copy gene. SmG10H expression was upregulated by treatment with methyljasmonate (MeJA) over a period from 6 h to 36 h after treatment. Accumulation of swertiamarin increased after elicitation by MeJA. SmG10H was heterologously expressed in both Escherichia coli and Pichia pastoris (yeast), forming a 55.5-kDa protein. Based on analysis in vitro, SmG10H was found to have catalytic activity hydroxylating geraniol. In the SmG10H overexpression plants, the level of SmG10H transcript and the contents of 10-hydroxygeraniol and swertiamarin increased simultaneously.

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An N-acetylgalactosamine (GalNAc)-specific Ca²⁺-dependent lectin (C-type lectin), isolated from the marine invertebrate Holothuroidea (Cucumaria echinata), CEL-I, showed potent mitogenic activity toward normal mouse spleen cells. The mitogenic activity of CEL-I, which reached a maximum at 100 μg/ml, was inhibited by GalNAc in a concentration-dependent manner. The mitogenic effect of CEL-I at 10 μg/ml on T cell- enriched splenocytes was at a similar level due to a well-known T cell mitogen, concanavalin A (Con A), at 10 μg/ml. Furthermore, CEL-I evoked a mitogenic response from nude mouse spleen cells, while no significant effects of Con A on this cell population were observed over a wide range of concentrations. These results suggest that CEL-I is a potent mitogenic lectin with the ability to stimulate both T and B cells.

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Corynebacterium glutamicum is widely used in the industrial production of amino acids. Producer strains are generated by classical random mutagenesis, and therefore have detrimental characteristics caused by unnecessary mutations. Increased alkali sensitivity is one of those undesired characteristics. We found that one of the laboratory strains, AJ12036ΔcspAΔcspB, showed decreased growth under alkaline conditions. To clarify which mutation is responsible for alkali sensitivity, we constructed mutant strains carrying the ΔcspA and/or ΔcspB mutations from wild-type strain ATCC13869. We found that disruption of cspA encoding a mycolyltransferase alone caused increased alkali sensitivity. The ΔcspA mutant also showed increased susceptibility to ethambutol, penicillin, and rifampicin. Disruption of cspB had no effect on alkali sensitivity or drug sensitivity. These results indicate that the mycolate layer is important for alkali sensitivity as well as drug susceptibility in this bacterium.

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Membrane-associated hydrogenase was purified from the chemolithoautotrophic epsilonproteobacterium Hydrogenimonas thermophila at 152-fold purity. The hydrogenase was found to be localized in the periplasmic space, and was easily solubilized with 0.1% Triton X-100 treatment. Hydrogen oxidation activity was 1,365 μmol H₂/min/mg of protein at 80 °C at pH 9.0, with phenazine methosulphate as the electron acceptor. Hydrogen production activity was 900 μmol H₂/min/mg of protein at 80 °C and pH 6.0, with reduced methyl viologen as the electron donor. The hydrogenase from this organism showed higher oxygen tolerance than those from other microorganisms showing hydrogen oxidation activity. The structural genes of this hydrogenase, which contains N-terminal amino acid sequences from both small and large subunits of purified hydrogenase, were successfully elucidated. The hydrogenase from H. thermophila was found to be phylogenetically related with H₂ uptake hydrogenases from pathogenic Epsilonproteobacteria.

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Basic 7S globulin, a cysteine-rich protein from soybean seeds, consists of subunits containing 27 kD and 16 kD chains linked by disulfide bonding. Three differently sized subunits of the basic 7S globulin were detected and partially separated by SP Sepharose chromatography. The basic 7S globulin was characterized as a member of a superfamily of structurally related but functionally distinct proteins descended from a specific group of plant aspartic proteinases.

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D-Galactosyl-β1→4-L-rhamnose (GalRha) was produced enzymatically from 1.1 M sucrose and 1.0 M L-rhamnose by the concomitant actions of four enzymes (sucrose phosphorylase, UDP-glucose-hexose 1-phosphate uridylyltransferase, UDP-glucose 4-epimerase, and D-galactosyl-β1→4-L-rhamnose phosphorylase) in the presence of 1.0 mM UDP-glucose and 30 mM inorganic phosphate. The accumulation of GalRha in 1 liter of the reaction mixture reached 230 g (the reaction yield was 71% from L-rhamnose). Sucrose and fructose in the reaction mixture were removed by yeast treatment, but isolation of GalRha by crystallization after yeast treatment was unsuccessful. Finally, 49 g of GalRha was isolated from part of the reaction mixture with yeast treatment by gel-filtration chromatography.

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O-Linked N-acetylglucosamine (O-GlcNAc), a single GlcNAc modification of proteins, is abundant in nucleocytoplasmic proteins of eukaryotes. Most nuclear transcriptional regulator proteins carry O-GlcNAc, implicating O-GlcNAc in gene regulation. This study suggested the possibility that O-GlcNAc regulates cooperative binding of Sp1 and its collaborating transcription factors, Oct1 and Elf-1, onto DNA templates in vivo. Chromatin immunoprecipitation assays on cells in which O-GlcNAc was modulated pharmacologically revealed that Sp1-Oct1- and Sp1-Elf-1-paired occupancies of previously known target promoter regions were suppressed by elevated O-GlcNAc modification. Since these pairs of transcription factors bind the target promoters cooperatively and DNA binding of Sp1 alone is not affected by O-GlcNAc, our results imply that O-GlcNAc weakens the DNA binding of Sp1 and its cooperative binding partners by inhibiting stable interaction on DNA templates.

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Myoglobin (Mb) purified from fast skeletal muscle of bluefin tuna Thunnus thynnus orientalis was subjected to thermal treatment, and the denaturation profiles were examined by thermodynamic analysis. Based on the ellipticity or helical content obtained by circular dichroism (CD) spectrometry, it was found that denaturation of tuna Mb consisted of three steps, and that slight structural changes of Mb started below 20 °C. However, major structural changes were observed at around 58 and 72 °C. Differential scanning calorimetry (DSC) analysis revealed a similar but somewhat different thermal denaturation profile of Mb. In comparison with the denaturing profiles of whale Mb under the same conditions, the thermal stability of tuna Mb was found to be much lower. In the modeled tertiary structures of these Mbs, they were roughly similar to each other, though minor conformational differences were recognized and the total energy was found to be lower for tuna Mb.

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Although termites are known to have a highly efficient lignocellulose-digesting system, mass production of native endogenous cellulases of termites has failed in Escherchia coli, and in Saccharomyces cerevisiae, and it has not been accomplished. Here we report the successful production, purification, and characterization of two termite endogenous β-1,4-endoglucanases, RsEG and NtEG, from the salivary gland of Reticulitermes speratus and the midgut of Nasutitermes takasagoensis respectively, using Aspergillus oryzae as host. Thin-layer chromatography analysis showed that both enzymes hydrolyzed the β-1,4-cellulosic linkage of cellodextrin into cellobiose and glucose. Kinetic studies indicated that the specific activity and Vmax values of the two enzymes were significantly higher than those of previously reported fungal and bacterial endoglucanases.

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We prepared chitosan sulfated derivatives to address the common structural requirement of the sulfate pattern to block P-selectin-mediated tumor cell adhesion. Our results indicate that 6-O-sulfation of chitosan is indispensable for inhibition of P-selectin binding to human melanoma A375 cells. Furthermore, additional N-sulfation or 3-O-sulfation dramatically enhanced the inhibitory activity of 6-O-sulfated chitosan, suggesting that efficient anti-P-selectin adhesion activity of sulfated saccharides requires the synergy of 6-O-sulation and N- or 3-O-sulfation in glucosamine units.

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The effects of kaempferol on redox-associated enzymes in normal human keratinocytes were studied. It enhanced the gene expression of thioredoxin reductase 1 and thioredoxin. Flavonols had higher ability to induce the expression of these genes than the other anti-oxidants and the other flavonoids tested. Furthermore, kaempferol and quercetin increased the activity of thioredoxin reductase in normal human keratinocytes.

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A genomic DNA sequence and cDNA encoding a putative chitin synthase were isolated from the white rot basidiomycete Lentinula edodes. The gene, named LeChs2, consists of a 2,598-bp open reading frame interrupted by 14 introns and encodes a putative protein of 866 amino acid residues. The data obtained in this study suggest that LeChs2 belongs to the class II chitin synthases.

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cDNA encoding an extracellular carbohydrate esterase (CcEst1) was cloned from the basidiomycete Coprinopsis cinerea. The recombinant CcEst1 expressed in Pichia pastoris acted on p-nitrophenyl acetate, α-naphthyl acetate, and methyl hydroxycinnamic acids, except for methyl sinapic acid. The enzyme released ferulic and acetic acids from wheat arabinoxylan and acetylated xylan respectively. Activity increased on the addition of endo-β-1,4-xylanase.

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A practical purification method for a non-digestible disaccharide, epilactose (4-O-β-galactosyl-D-mannose), was established. Epilactose was synthesized from lactose with cellobiose 2-epimerase and purified by the following procedure: (i) removal of lactose by crystallization, (ii) hydrolysis of lactose by β-galactosidase, (iii) digestion of monosaccharides by yeast, and (iv) column chromatography with Na-form cation exchange resin. Epilactose of 91.1% purity was recovered at 42.5% yield.

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In this study, we analyzed the antioxidant and antimelanogenic properties of a variety of solvent extracts of pre-bloom and full-bloom chestnut flowers. Among the solvent extracts, a pre-bloom methanol extract (preM) and an ethanol extract (preE) showed the highest amounts of phenolics (467.92±0.45 and 456.24±5.88 mg of gallic acid equivalent/g of extract) and flavonoids (60.96±1.86 and 41.59±8.57 mg of quercetin equivalent/g of extract). These extracts exhibited the highest DPPH radical and reducing activities, as well as the greatest mushroom tyrosinase inhibition activity. In addition, preE effectively protected the skin against ultraviolet (UV) rays. Further, extracts were tested for cytotoxicity on human melanoma cells (SK-MEL-2), and we observed that all the extracts were non-cytotoxic for the cells. Their effects on tyrosinase and melanin inhibitory action were further assessed, and we found that all the extracts reduced the tyrosinase activity and melanin formation of SK-MEL-2 cells as effectively as arbutin. Moreover, the protein level expression of tyrosinase decreased dramatically. However, the protein levels of the other melanogenic enzymes, tyrosinase-related protein 1 (TRP1) and dopachrome tautomerase (DCT), were not altered significantly. Therefore, the antimelanogenic effects of chestnut flower extracts were attributable to their inhibitory effects on tyrosinase via their anti-oxidative action, making them a strong candidate for use in food, cosmetics, and pharmaceutical applications.

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The effect was examined of dietary sericin on the lipid and carbohydrate metabolism in rats fed with a high-fat diet. The rats were fed with a 20% beef tallow diet with or without sericin at the level of 4% for 5 weeks. The final body weight and white adipose tissue weight were unaffected by dietary manipulation. The consumption of sericin significantly reduced the serum levels of triglyceride, cholesterol, phospholipids and free fatty acids. Serum very-low-density lipoprotein (VLDL)-triglyceride, VLDL-cholesterol, low-density lipoprotein (LDL)-cholesterol and LDL-phospholipids were also significantly reduced by the sericin intake. Liver triglyceride and the activities of glucose 6-phosphate dehydrogenase and malic enzyme, the lipogenic enzymes, were also reduced by the sericin intake. Dietary sericin caused a marked elevation in serum adiponectin. The consumption of sericin suppressed the increases in plasma glucose and insulin levels after an intraperitoneal glucose injection. These results imply the usefulness of sericin for improving the lipid and carbohydrate metabolism in rats fed on a high-fat diet.

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The expression of cell adhesion molecules (CAMs) has been implicated as one of the most important causes of the development of inflammatory diseases such as atherosclerosis, and, it is speculated that the prevention of it is an effective approach to the control of atherosclerosis. In the present study, we investigated the effect of sesame lignans on the expression of CAMs in human umbilical vein endothelial cells (HUVECs) induced by tumor necrosis factor-α (TNF-α). Based on cell-ELISA analysis, we found that sesaminol-6-catechol downregulated the TNF-α-induced expression of CAMs in a dose-dependent manner. Moreover, these inhibitory effects were caused to be drastically exerted by downregulating the CAM proteins in TNF-α-activated HUVECs at transcriptional level. This suggests, that sesaminol-6-catehcol suppresses the expression of CAMs, and may be an active component of sesame lignans.

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We investigated energy metabolism enhancement by pepper by examining suppression of body fat accumulation in mice due to piperine (PIP) and black pepper (BP) intake. To induce adiposity, mice were fed a high-fat, high-sucrose (HFS) diet as a control diet for 4 weeks. Visceral fat weights decreased significantly in the mice fed diets of 0.03% and of 0.05% PIP. Body weight in the 0.05% PIP group also decreased significantly. In the mice fed a diet of 1.0% BP, body weight and visceral fat weights decreased significantly. For all parameters tested, the 1.0% BP group tended to show values slightly lower than those of the 0.03% PIP group. Expression of thermogenic protein uncoupling protein 1 tended to increase in the mice on the 1.0% BP diet. These results indicate that BP suppresses the effect of body fat accumulation mainly through the action of PIP.

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Agarwood (Aquilaria sinensis, Aquilaria crasna) is well known as an incense in the oriental region such as Thailand, Taiwan, and Cambodia, and is used as a digestive in traditional medicine. We investigated the laxative effects and mechanism of agarwood leaves extracted with ethanol (EEA-1, Aquilaria sinensis; EEA-2, Aquilaria crasna). EEA-1, EEA-2, the main constituents of EEAs (mangiferin, and genkwanin-5-O-primeveroside), and senna increased the frequency and weight of stools in loperamide-induced constipation model mice. EEA-1 and EEA-2 did not induce diarrhea as a side effect, but senna induced severe diarrhea. EEA-1 and senna increased gastro-intestinal (GI) transit in the model mice. EEA-1, but not senna, also increased the intestinal tension of isolated jejunum and ileum in guinea pigs, and the tension increase was blocked by atropine, a muscarinic receptor antagonist, but not by other inhibitors (granicetron, pyrilamine, or bradykinin-antagonist peptide). Furthermore, the increase in frequency and weight of stools induced by EEA-1 were blocked by pre-administration of atropine in the model mice. These findings indicate that EEAs exerted a laxative effect via acetylcholine receptors in the mouse constipation model.

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The dependence of the dynamic viscoelastic parameters of carboxymethylcellulose (CMC), xanthan gum, and guar gum solutions on the angular frequency (ω) was compared with that of their viscosity (μ) on the shear rate (γ). In addition, the effect of these rheological properties on the maximum velocity through the pharynx, V_max, as measured by the ultrasonic pulse Doppler method, was investigated. The CMC and guar gum solutions examined were taken as a dilute solution and a true polymer solution, respectively. The xanthan gum solution was taken as a weak gel above 0.5% and a true polymer solution below 0.2%. The maximum velocity, V_max, of the thickener solutions correlated well with μ, the dynamic viscosity η′, and the complex viscosity η^*, especially those measured at γ or ω of 20–30 s⁻¹ (or rad/s) and above, suggesting that μ, η′, and η^* are suitable indexes for care foods of the liquid type for dysphagic patients.

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We manufactured a new fermented tea by tea-rolling processing of third-crop green tea (Camellia sinensis) leaves and loquat (Eriobotrya japonica) leaves. The mixed fermented tea extract inhibited pancreatic lipase activity in vitro, and effectively suppressed postprandial hypertriacylglycerolemia in rats. Rats fed a diet containing 1% freeze-dried fermented tea extract for 4 weeks had a significantly lower liver triacylglycerol concentration and white adipose tissue weight than those fed the control diet lacking fermented tea extract. The activity of fatty acid synthase in hepatic cytosol markedly decreased in the fermented tea extract group as compared to the control group. The serum and liver triacylglycerol- and body fat-lowering effects of the mixed fermented tea extract were strong relative to the level of dietary supplementation. These results suggest that the new fermented tea product exhibited hypotriacylglycerolemic and antiobesity properties through suppression of both liver fatty acid synthesis and postprandial hypertriacylglycerolemia by inhibition of pancreatic lipase.

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The aim of the present study was to evaluate the anti-obesity activity of a probiotic bifidobacterial strain in a mouse model with obesity induced by a high-fat diet. The mice were fed a high-fat diet supplemented with Bifidobacterium breve B-3 at 10⁸ or 10⁹ CFU/d for 8 weeks. B. breve B-3 supplementation dose-dependently suppressed the accumulation of body weight and epididymal fat, and improved the serum levels of total cholesterol, fasting glucose and insulin. The bifidobacterial counts in the caecal contents and feces were significantly increased with the B. breve B-3 administration. The expression of genes related to fat metabolism and insulin sensitivity in the gut and epididymal fat tissue was up-regulated by this administration. These results suggest that the use of B. breve B-3 would be effective in reducing the risk of obesity.

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A hot-water extract of Aphanothece sacrum, an edible aquacultured blue-green alga, was found to show a remarkable inhibitory effect on the replication of enveloped viruses including herpes simplex virus type 2 (HSV-2) and influenza virus type A (IFV-A, H1N1) in vitro. The main active components were suggested to be sulfated polysaccharides in non-dialyzable portion (ASWPH). ASWPH was found to inhibit the viral adsorption to the receptor of the host cells involved in the replication process of HSV-2 and IFV-A. In addition, while the penetration stage of HSV-2 was also significantly suppressed with ASWPH, no such effect was observed in the replication of IFV-A. These results suggest that ASWPH might be useful in the prevention of infectious diseases caused by HSV-2 as well as IFV-A.

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Weaning rats were fed a 5% or 30% fat diet containing limited calcium pantothenate for 28 d. The plasma, liver and adrenal pantothenic acid levels in the rats fed on the 30% fat diet were significantly lower than with the 5% fat diet. The results suggest that the high-fat diet affected pantothenic acid metabolism.

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We investigated the activation of transient receptor potential cation channel (TRP) subfamily V, member 1 (TRPV1) and TRP subfamily A, member 1 (TRPA1) by 1′-acetoxychavicol acetate (ACA), the main pungent component in galangal. ACA did not activate TRPV1-expressing human embryonic kidney (HEK) cells, but strongly activated TRPA1-expressing HEK cells. ACA was more potent than allyl isothiocyanate, the typical TRPA1 agonist.

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We found renin inhibitory activity in rice. The physico-chemical data on the isolated inhibitors were identical to those of oleic acid and linoleic acid. Oleic acid and linoleic acid competitively inhibited renin activity, with K_i values of 15.8 and 19.8 μM respectively. Other unsaturated free fatty acids also inhibited renin activity, but saturated fatty acids had no effect on it.

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We tested synthetic food colorants for their antioxidative potential by the in vitro superoxide generation assay in differentiated HL-60 cells in response to phorbol ester. Among the 12 colorants tested, such fluorescein-type red colorants as rose bengal showed potent inhibitory activity without any cytotoxicity under dark conditions. The intracellular accumulation and superoxide anion scavenging effect of rose bengal were at least partly involved in the inhibitory activity.

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This study was designed to identify a novel peptide derived from soybean protein that induces inhibition of cholesterol absorption in vivo. VAWWMY (Val-Ala-Trp-Trp-Met-Tyr, designated soystatin) had a significantly greater ability to bind bile acid than soybean protein peptic hydrolysate (SPH) or casein tryptic hydrolysate (CTH). Surprisingly, the bile-acid binding ability of VAWWMY was almost as strong as that of the hypocholesterolemic medicine cholestyramine. The micellar solubility of cholesterol was significantly lower in the presence of VAWWMY than in that of SPH or CTH. We found that soystatin derived from soybean glycinin acted as an inhibitor of cholesterol absorption in vivo.

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Physio-chemical changes in oyster shell were examined, and fresh and composted oyster shell meals were compared as lime fertilizers in soybean cultivation. Structural changes in oyster shell were observed by AFM and FE-SEM. We found that grains of the oyster shell surface became smoother and smaller over time. FT-IR analysis indicated the degradation of a chitin-like compound of oyster shell. In chemical analysis, pH (12.3±0.24), electrical conductivity (4.1±0.24 dS m⁻¹), and alkaline powder (53.3±1.12%) were highest in commercial lime. Besides, pH was higher in composted oyster shell meal (9.9±0.53) than in fresh oyster shell meal (8.4±0.32). The highest organic matter (1.1±0.08%), NaCl (0.54±0.03%), and moisture (15.1±1.95%) contents were found in fresh oyster shell meal. A significant higher yield of soybean (1.33 t ha⁻¹) was obtained by applying composted oyster shell meal (a 21% higher yield than with fresh oyster shell meal). Thus composting of oyster shell increases the utility of oyster shell as a liming material for crop cultivation.

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Tex was originally identified in Bordetella pertussis, where it serves as a transcriptional regulator of toxin genes. However, the Tex of Streptococcus pneumoniae has no regulatory function in the expression of the pneumococcal major toxin pneumolysin. Here, we identified the CPE2168 gene as Tex in Clostridium perfringens, and examined the roles of Tex in toxin gene expression. We found that the deletion mutant for Tex does not affect growth, but the mRNA levels of three hyaluronidase genes (nagH, nagJ, and nagL) and an exo-sialidase (nanJ) were reduced to less than 50% as compared to the parent strain, C. perfringens strain 13. On the other hand, Tex did not affect the expression of proteases, enterotoxins, hemolysins, either of two hyaluronidase genes (nagI and nagK), an exo-sialidase (nanI), or adhesins. Moreover, purified Tex bound to the 5′-portion of target gene mRNAs. Based on these results, we propose that Tex positively regulates the gene expression of a set of toxin genes in C. perfringens.

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Acetobacter pasteurianus strains IFO3283, SKU1108, and MSU10 were grown under acetic acid fermentation conditions, and their growth behavior was examined together with their capacity for acetic acid resistance and pellicle formation. In the fermentation process, the cells became aggregated and covered by amorphous materials in the late-log and stationary phases, but dispersed again in the second growth phase (due to overoxidation). The morphological change in the cells was accompanied by changes in sugar contents, which might be related to pellicle polysaccharide formation. To determine the relationship between pellicle formation and acetic acid resistance, a pellicle-forming R strain and a non-forming S strain were isolated, and their fermentation ability and acetic acid diffusion activity were compared. The results suggest that pellicle formation is directly related to acetic acid resistance ability, and thus is important to acetic acid fermentation in these A. pasteurianus strains.

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A newly isolated mutation (Gln508Leu) and a combination of it with previously discovered beneficial mutations in polyhydroxyalkanoate synthase 1 from Pseudomonas sp. 61-3 were found to enhance the production of poly(3-hydroxybutyrate) [P(3HB)] and poly(3HB-co-3-hydroxyalkanoate)s in recombinant Escherichia coli.

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Recombinant strains of Ralstonia eutropha and Pseudomonas putida harboring a chimeric polyhydroxyalkanoate (PHA) synthase, which consisted of PHA synthases of Aeromonas caviae and R. eutropha, produced 3-hydroxybutyrate (3HB)-based PHA copolymers comprised of 3-hydroxyhexanoate and 3-hydroxyoctanoate units from dodecanoate (87–97 mol % 3HB), indicating that the chimeric PHA synthase possesses desirable substrate specificity leading to the production of 3HB-rich copolymers.

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The fission yeast Schizosaccharomyces pombe was sensitive to salinity; cell growth was stopped by 0.5 M NaCl and by 10 mM LiCl. The avt5⁺ gene encodes a vacuolar transporter with a broad specificity for amino acids. We found that the avt5Δ mutant became highly tolerant of Li⁺ and Na⁺ in growth. Concanamycin A-sensitive Li⁺ uptake as well as cellular Li⁺ content was lower in the avt5 mutant, suggesting a role of Avt5p in cellular uptake of toxic Li⁺.

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A bacterium utilizing fucoidan from the brown alga Cladosiphon okamuranus as sole carbon source was isolated and identified as Flavobacterium sp. F-31. The strain produced intracellular enzymes involved in fucoidan degradation and desulfation, but desulfation activity was not detected until the molecular weight of fucoidan fell to less than several tens of thousands due to enzymatic degradation. Only fucoidan proved to be an inducible substance for the production of the degrading enzymes.

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In this paper, we describe the CTA1 gene, which encodes a peroxisomal catalase in the methylotrophic yeast Pichia methanolica. The P. methanolica CTA1 gene (PmCTA1) comprises a 1,530-bp open reading frame corresponding to a protein of 510 amino acid residues, and its deduced amino acid sequence shows high similarity to those of Cta1ps from other methylotrophic yeasts (about 79%). Expression of PmCTA1 in a peroxisomal catalase-depleted (Cbcta1Δ) Candida boidinii strain restored the methylotrophic growth of the host strain, while the expression of PmCTA1-ΔSRL, which lacks peroxisome targeting signal type 1, did not. In P. methanolica, expression of PmCTA1 was induced when cells were grown on peroxisome-inducing carbon sources, viz., methanol, oleate, and D-alanine. Taken together, these results indicate that PmCTA1 encodes a functional peroxisomal catalase in P. methanolica.

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Rice plants are known to accumulate starch in leaf sheaths and culms, and in some cultivars significant amounts of starch are present at the mature stage. This can be considered as potential feedstock for the recovery of fermentable sugars. We isolated starches from the culms of cultivars Yumeaoba, Koshihikari, and Leafstar to investigate their structural and physical features. Yumeaoba culm starch contained 20.2% amylose, whereas Koshihikari and Leafstar contained 25.8% and 25.2%. Yumeaoba culm starch was found by chain-length distribution analysis to contain higher amounts of short chains, resulting in lower gelatinization temperature by 7 °C, as compared to Koshihikari and Leafstar. Consequently, the rate of enzymatic hydrolysis of Yumeaoba culm starches reached maximum at a lower temperature than Leafstar. Rice culm starch, with a lower gelatinization temperature, can provide an advantageous material for feedstock for bioethanol production in terms of energy conservation.

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