Research on microbial degradation of xenobiotic polymers has been underway for more than 40 years. It has exploited a new field not only in applied microbiology but also in environmental microbiology, and has greatly contributed to polymer science by initiating the design of biodegradable polymers. Owing to the development of analytical tools and technology, molecular biological and biochemical advances have made it possible to prospect for degrading microorganisms in the environment and to determine the mechanisms involved in biodegradation when xenobiotic polymers are introduced into the environment and are exposed to microbial attack. In this review, the molecular biological and biochemical aspects of the microbial degradation of xenobiotic polymers are summarized, and possible applications of potent microorganisms, enzymes, and genes in environmental biotechnology are suggested.

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The status quo of flavonoid biosynthesis as it relates to flower color is reviewed together with a success in modifying flower color by genetic engineering. Flavonoids and their colored class compounds, anthocyanins, are major contributors to flower color. Many plant species synthesize limited kinds of flavonoids, and thus exhibit a limited range of flower color. Since genes regulating flavonoid biosynthesis are available, it is possible to alter flower color by overexpressing heterologous genes and/or down regulating endogenous genes. Transgenic carnations and a transgenic rose that accumulate delphinidin as a result of expressing a flavonoid 3′,5′-hydroxylase gene and have novel blue hued flowers have been commercialized. Transgenic Nierembergia accumulating pelargonidin, with novel pink flowers, has also been developed. Although it is possible to generate white, yellow, and pink-flowered torenia plants from blue cultivars by genetic engineering, field trial observations indicate difficulty in obtaining stable phenotypes.

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The IgE-suppressive activity of (−)-matairesinol is demonstrated, and the structure-activity relationship of (−)-matairesinol clarified. 3′,4-Dihydroxy-3,4′-dimethoxylignano-9,9′-lactone showed higher IgE-suppressive activity than (−)-matairesinol without any cytotoxic activity. Some derivatives bearing a longer and more bulky alkoxy group at the 3 or 4 position showed IgE-accelerative activity.

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In field screening tests of synthetic pheromone candidates for Japanese sesiid species, a mixture of (3Z,13Z)-octadecadien-1-ol and (3Z,13Z)-octadecadienyl acetate successfully attracted male moths of Glossosphecia romanovi, a harmful pest of vine trees. The GC-EAD and GC-MS analyses of the pheromone gland extract revealed that the female moths produced the alcohol and acetate in a ratio of about 20:1, in addition to three other minor structure-related components.

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Two serotonin derivatives, N,N-dimethylserotonin 5-O-β-glucoside (1a) and N-methylserotonin 5-O-β-glucoside (1b) were isolated from immature seeds of Zanthoxylum piperitum. Their structures were determined by multi-step conversion reactions and spectroscopic analyses. Immature seeds of Z. piperitum contained extremely high levels of compounds 1a and 1b of approximately 0.29% and 0.15% (w/w), respectively.

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A concise synthesis of valerena-4,7(11)-diene with potent sedative activity was achieved in three steps involving, reduction of carboxylic acid, bromination of the resulting alcohol, and reduction of the bromide from valerenic acid in a 63% total yield. This synthetic method makes it possible to provide further materials for biological testing to realize comprehensive SAR studies.

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6-O-Dodecanoyl-2-O-α-D-glucopyranosyl-L-ascorbic acid (6-sDode-AA-2G) was synthesized from 2-O-α-D-glucopyranosyl-L-ascorbic acid and vinyl laurate with a protease from Bacillus subtilis in 30% dimethylformamide (DMF)/dioxane with a low water content. The addition of 3% (v/v) water to DMF/dioxane dramatically enhanced the 6-sDode-AA-2G synthesis. The optimum reaction conditions enabled 6-sDode-AA-2G to be synthesized in a yield of 38.1%.

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The effect of NADH on melanogenesis under aerobic conditions involves three types of reaction: (a) acting as tyrosinase substrate (a competitive substrate of L-tyrosine and L-DOPA), (b) irreversible inactivation acting as a suicide substrate of tyrosinase, and (c) non-enzymatic reduction of o-dopaquinone by NADH. Under anaerobic conditions, NADH irreversibly inhibits the enzymatic forms met-tyrosinase and deoxy-tyrosinase. In this paper, we kinetically characterize this coenzyme as it acts as a tyrosinase suicide substrate and propose a kinetic mechanism to explain its oxidation by tyrosinase. In addition, the compound is characterized as an irreversible inhibitor of met-tyrosinase and deoxy-tyrosinase.

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We investigated the effects of a topically applied extract of the heartwood of Broussonetia kazinoki Sieb (B. kazinoki) on atopic dermatitis (AD)-like skin lesions induced by an extract of the house-dust mite Dermatophagoides farina in NC/Nga mice. We found that topically applied B. kazinoki extract suppressed the histological manifestations of AD-like skin lesions, and decreased the levels of plasma immunoglobulin E (IgE) and interleukin-4 (IL-4) in the mice. Moreover, B. kazinoki inhibited the induction of thymus-and-activation-regulated chemokine (TARC/CCL17), macrophage-derived chemokine (MDC/CCL22), and regulated-on-activation-normal T cell-expressed-and-secreted chemokine (RANTES/CCL5) in HaCaT cells activated by tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma). In conclusion, our results suggest that B. kazinoki extract has therapeutic advantages in the treatment of AD.

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ALG-2, a member of the penta-EF-hand protein family, interacts Ca²⁺-dependently with a COPII component, Sec31A. In this study, we first established HeLa cells stably expressing green fluorescent protein-fused ALG-2 (GFP-ALG-2) and red fluorescent protein-fused Sec31A (Sec31A-RFP). After inducing Ca²⁺-mobilization, the cytoplasmic distribution of GFP-ALG-2 changed from a diffuse to a punctate pattern, which extensively overlapped with the Sec31A-RFP-positive structures, indicating that ALG-2 is recruited to the endoplasmic reticulum exit sites (ERES) in living cells. Next, overlay experiments with biotin-labeled ALG-2 were done to dissect the ALG-2 binding site (ABS). They revealed that a sequence comprising amino acid residues 839–851 in the Pro-rich region was necessary and sufficient for direct binding to ALG-2. Finally, fluorescence recovery after photobleaching analysis indicated that the ABS deletion reduced the high-affinity population of Sec31A to the ERES, suggesting that the ABS is one of the key determinants of the retention kinetics of Sec31A at ERES.

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A cyanobacterium, semi-filamentous multicellular strain ABRG5-3, was isolated and its unique nature was characterized. This axenic strain formed colonies and was motile on an agarose plate. The 16S rRNA gene of ABRG5-3 exhibited similarities to those of the Limnothrix and Pseudanabaena strains, which are known as filamentous and nonheterocystous cyanobacteria. Peaks in absorbance for the accumulation of chlorophyll a, phycocyanin, and phycoerythrin were observed in the cell extract. Natural separation of the pigments occurred in the supernatant of the autolysed cells. The cell lysis was promoted by osmotic shocks and lysozyme treatments. Chlorophyll a and total DNA were abundantly recovered from the cells. Analysis of the restriction-modification system for genomic DNA revealed novel diversity. Moreover, we made a successful attempt to create antibiotic-resistant strains by conjugation with a foreign plasmid, which indicates that strain ABRG5-3 is transformable.

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We developed the in vitro immunization method to induce antigen-specific immune responses in human peripheral blood mononuclear cells (PBMCs). However, when we used a peptide as sensitizing antigen, the antigen-specific immune response was found to be weak, and hence, we could not effectively obtain the antigen-specific antibody gene. In the present study, we attempted to improve the in vitro immunization method by augmenting the immune response to the peptide antigen. We used a multiple antigen peptide for sensitization. In vitro immunization of the multivalent antigen elicited a strong antigen-specific immune response in the PBMCs, and we succeeded in obtaining antigen-specific antibody genes by the phage-display method. Further, by combining the variable-region genes and constant-region genes of human IgG, we obtained four independent human monoclonal antibodies specific for tumor necrosis factor-α. This might be a good strategy for generating antigen-specific human monoclonal antibodies using a peptide antigen.

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Oil bodies were observed in cells of both embryo and aleurone layers of mature adlay grains (Coix lachryma-jobi L. var. ma-yuen Stapf). Stable oil bodies were successfully isolated from the adlay grains. Thin-layer chromatography revealed that the contents stored in the adlay oil bodies were mainly neutral lipids (>90% triacylglycerols and about 5% diacylglycerols). The integrity of the isolated oil bodies was presumably maintained via electronegative repulsion and steric hindrance provided by their surface proteins. Immunological cross-recognition using antibodies against sesame oil-body proteins indicated that two oleosin isoforms (termed oleosin-H and oleosin-L) and one caleosin were present in the adlay oil bodies. Full-length cDNA fragments encoding these three unique oil-body proteins were obtained by PCR cloning. MALDI-MS analyses confirmed that the three full-length cDNA fragments encoded the two oleosin isoforms and one caleosin observed in the oil bodies isolated from the adlay grains.

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In this work, a metagenomic library was generated from peat-swamp forest soil obtained from Narathiwat Province, Thailand. From a fosmid library of approximately 15,000 clones, six independent clones were found to possess lipolytic activity at acidic pH. Analysis of pyrosequencing data revealed six ORFs, which exhibited 34–71% protein similarity to known lipases/esterases. A fosmid clone, designated LP8, which demonstrated the highest level of lipolytic activity under acidic conditions and demonstrated extracellular activity, was subsequently subcloned and sequenced. The full-length lipase/esterase gene, estPS2, was identified. Its deduced amino acid was closely related to a lipolytic enzyme of an uncultured bacterium, and contained the highly conserved motif of a hormone-sensitive family IV lipase. The EstPS2 enzyme exhibited highest activity toward p-nitrophenyl butyrate (C₄) at 37 °C at pH 5, indicating that it was an esterase with activity and secretion characteristics suitable for commercial development.

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Cordyceps sinensis (CS) is an herbal medicine that increases steroidogenesis in Leydig cells and improves male reproductive dysfunction. We have found that CS stimulates Leydig cell steroidogenesis through the protein kinase A and protein kinase C signaling pathways. In the present study, we sought to determine the mechanisms of CS-stimulated steroidogenesis in MA-10 mouse Leydig tumor cells. Using pharmacological approaches, we found that de novo protein synthesis, protein transcription, a calcium signal, and a mitochondria electrochemical gradient were required for CS-stimulated steroidogenesis in MA-10 cells. mRNA expression of steroidogenic acute regulatory protein was activated by CS. However, CS had an adversary effect on P450 side-chain cleavage enzyme activity, but not in 3β-hydroxysteroid dehydrogenase enzyme, in regulating MA-10 cell steroidogenesis. In conclusion, de novo protein synthesis, increased steroidogenic acute regulatory protein mRNA expression, and the mitochondria electrochemical gradient were involved in CS-stimulated steroidogenesis in MA-10 cells.

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Here we report a simple method for the structural analysis of red algal galactan containing 3,6-anhydrogalactose. Structural heterogeneity in the galactan was demonstrated by this method. For selective hydrolysis of 3,6-anhydrogalactosidic linkages in the galactan, conditions for reductive mild acid hydrolysis were examined by characterizing the resulting oligosaccharide alditols by anhydrous mercaptolysis. Residues other than alditols at the reducing ends, including labile 3,6-anhydrogalactose, were liberated quantitatively as diethyl dithioacetal derivatives, whereas alditols at the reducing ends were not derivatized and were liberated as alditols intact. The liberated sugars were then separated and measured quantitatively by gas-liquid chromatography. Heating of agarose in reductive hydrolysis with 0.3 M trifluoroacetic acid in the presence of an acid-stable reducing agent, 4-methyl morpholine borane, at 80 °C for 90 min and for 90 °C for 45 min was found to be optimum for the selective hydrolysis of 3,6-anhydrogalactosidic bonds, without detectable cleavage of other glycosidic bonds.

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A bacterial two-component signal transduction system, WalK/WalR, is essential to the cell viability of Gram-positive bacteria and is therefore a potential target for the development of a new class of antibiotics. We have solved the X-ray crystal structure of the DNA-binding domain of the response regulator WalR (WalRc) from a Gram-positive pathogen Staphylococcus aureus, currently causing serious problems in public health through the acquisition of multi-drug resistance. The structure contains a winged helix-turn-helix motif and closely resembles those of WalRs of Bacillus subtilis and Enterococcus faecalis, and also that of PhoB of Escherichia coli. Gel mobility shift assays with mutant WalRs revealed specific interactions of WalR with the target DNA, as elaborated by in silico modeling of the WalRc-DNA complex.

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In this study, the inhibitory effect of Elephantopus mollis H.B. and K. extract on melanogenesis in B16 murine melanoma cells was examined and possible mechanisms were elucidated. The melanin content in B16 cells decreased when they were treated with E. mollis extract. Inhibition was accompanied by reduced expression of tyrosinase (TYR) and tyrosinase-related protein 1 (TRP1). Furthermore, the expression level of microphthalmia-associated transcription factor (MITF), a major transcriptional regulator of genes encoding melanogenic enzymes such as Tyr and Trp1, decreased as assessed by western blotting and quantitative reverse transcriptase polymerase chain reaction (RT-PCR). These results suggest that E. mollis extract reduces melanogenesis by downregulating Mitf expression, leading to reduced expression of Tyr and Trp1. In addition, melanocortin-1 receptor (MC1R) expression was downregulated by E. mollis extract, suggesting desensitization to α-melanocyte-stimulating hormone (α-MSH) of cells treated with the extract.

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TP-110, a novel proteasome inhibitor, has been found to possess potent growth inhibition in human multiple myeloma cells. To enhance its therapeutic effects, we established TP-110-resistant RPMI-8226 (RPMI-8226/TP-110) cells and elucidated their resistance mechanisms. The IC₅₀ value for TP-110 cytotoxicity in the RPMI-8226/TP-110 cells was about 10-fold higher than that of the parental sensitive cells. The RPMI-8226/TP-110 cells exhibited distinct drug resistance to other proteasome inhibitors. Furthermore, they showed high cross-resistance to the cytotoxic effects of doxorubicin, etoposide, taxol, and vincristine. P-glycoprotein (MDR1), encoded by ABCB1, was elevated in the RPMI-8226/TP-110 cells, and the MDR1 inhibitor verapamil overcame their resistance to TP-110. The results of DNA microarray and RT-PCR suggested that the expression of ABCB1 is significantly elevated in RPMI-8226/TP-110 cells. This indicates that resistance in RPMI-8226/TP-110 cells is involved in the expression of P-glycoprotein, a drug-efflux pump.

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Biotransformations of phenylpropanoids such as cinnamic acid, p-coumaric acid, caffeic acid, and ferulic acid were investigated with plant-cultured cells of Eucalyptus perriniana. The plant-cultured cells of E. perriniana converted cinnamic acid into cinnamic acid β-D-glucopyranosyl ester, p-coumaric acid, and 4-O-β-D-glucopyranosylcoumaric acid. p-Coumaric acid was converted into 4-O-β-D-glucopyranosylcoumaric acid, p-coumaric acid β-D-glucopyranosyl ester, 4-O-β-D-glucopyranosylcoumaric acid β-D-glucopyranosyl ester, a new compound, caffeic acid, and 3-O-β-D-glucopyranosylcaffeic acid. On the other hand, incubation of caffeic acid with cultured E. perriniana cells gave 3-O-β-D-glucopyranosylcaffeic acid, 3-O-(6-O-β-D-glucopyranosyl)-β-D-glucopyranosylcaffeic acid, a new compound, 3-O-β-D-glucopyranosylcaffeic acid β-D-glucopyranosyl ester, 4-O-β-D-glucopyranosylcaffeic acid, 4-O-β-D-glucopyranosylcaffeic acid β-D-glucopyranosyl ester, ferulic acid, and 4-O-β-D-glucopyranosylferulic acid. 4-O-β-D-Glucopyranosylferulic acid, ferulic acid β-D-glucopyranosyl ester, and 4-O-β-D-glucopyranosylferulic acid β-D-glucopyranosyl ester were isolated from E. perriniana cells treated with ferulic acid.

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The use of certain organic chemicals has been found to improve yields and specificity in PCR. In this study, we examined the effects of dimethyl sulfoxide (DMSO), formamide, and glycerol on the reverse transcription reaction catalyzed by reverse transcriptases (RTs) from avian myeloblastosis virus (AMV) and Moloney murine leukemia virus (MMLV). At 42 °C, DMSO at 24% v/v and formamide at 12–14% inhibited the cDNA synthesis reaction, but DMSO at 12% and formamide at 6–8% improved the efficiency of the cDNA synthesis reaction at low temperatures (25–34 °C). Glycerol at 10% improved the efficiency of the cDNA synthesis reaction at high temperatures (49–61 °C). The effects of DMSO and formamide appeared to be accompanied by decreases in the melting temperatures of the primers, and the effect of glycerol was due to increases in the thermal stabilities of AMV RT and MMLV RT.

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γ-Glutamyltranspeptidase from Pseudomonas nitroreducens IFO12694 (PnGGT) exhibited higher hydrolytic activity than transfer activity, as compared with other γ-glutamyltranspeptidases (GGTs). PnGGT showed little activity towards most of L-amino acids and towards glycyl-glycine, which is often used as a standard γ-glutamyl accepter in GGT transfer reactions. The preferred substrates for PnGGT as a γ-glutamyl accepter were amines such as methylamine, ethylamine, and isopropylamine.

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An esterase gene from Neisseria sicca SB encoding CaeA, which catalyzes the deacetylation of cellulose acetate, was cloned. CaeA contained a putative catalytic domain of carbohydrate esterase family 1 and a carbohydrate-binding module (CBM) family 2. We constructed two derivatives, with and without the CBM of CaeA. Binding assay indicated that the CBM of CaeA had an affinity for cellulose.

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Phosphatidylserine plays an important role in cell membranes. We have reported the occurrence of phosphatidyl-D-serine (D-PS) in the rat cerebrum. Here, we describe the tissue distribution of D-PS in the rat. The D/D+L ratio of D-PS in the cerebrum was 0.9%, while no detectable amount of D-PS was detected in the cerebellum. D-PS was also found in the heart, spleen, lung, testis, liver, and kidney in a range of 0.05–0.7% (the D/D+L ratio). Thus, D-PS, even in small amounts, is localized to the cerebrum in the brain and is distributed to various tissues other than the brain in the rat.

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Multinucleation is indispensable to the bone-resorbing activity of mature osteoclasts. Nevertheless, little is known about the regulatory networks among multi-nuclei in a single mature osteoclast. For this reason, we purified osteoclastic factors from the nuclear envelope by two-dimensional gel electrophoresis. Two annexin family proteins and ferritin light chain 1 protein were identified as osteoclastic candidates.

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We investigated macrophage activation by fucoidan from Laminaria angustata var. longissima in a murine macrophage cell line, RAW 264.7. The ratio of the chemical composition of the fucoidan was L-fucose:D-galactose:D-glucose:D-xylose:uronic acid:sulfate = 1.00:0.54:0.08:0.08:0.64:0.87. The fucoidan induced production of nitric oxide, tumor necrosis factor-α, and interleukin-6 in RAW 264.7 cells. These results indicate that the fucoidan induced macrophage activation.

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Androgenic compounds induce an interaction between the NH₂- and COOH-terminal regions (N–C interaction) of androgen receptor (AR). We describe a rapid yeast bioassay for androgenic and anti-androgenic compounds based on androgen-dependent β-catenin-enhanced N–C interaction. The bioassay was also effective at detecting compounds that inhibit the N–C interaction in ways that do not involve binding to the ligand-binding domain.

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The optimized conditions were evaluated for solid-phase microextraction (SPME) to investigate the headspace volatiles in fish miso, a Japanese fish meat-based fermented product. The influence on the efficiency for microextraction of such parameters as the sample size, isolation time and temperature, sensitivity and selectivity of several SPME fibers of different liquid phases as well as several extraction techniques was evaluated. Suitable reproducibility and sensitivity of SPME were achieved by combining carbowax/divenylbenzene of 65 μm thickness as the liquid phase of SPME, 3 g of fish miso, 40 °C of isolation temperature and 40 min of isolation time. The headspace volatiles of fish miso prepared from spotted mackerel were analyzed under the optimized conditions. Although several volatiles contributed to fish miso, certain volatile esters might have played the greatest role in imparting the sweet-fruity aroma to the product.

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The results of our previous in vitro study indicated that the intensity of the Ca²⁺ signal could determine T cell activation and anergy. We show here that the T cell response of mice that had been treated with cyclosporine A during oral tolerance induction was higher than that of control mice, indicating that the Ca²⁺ signal could also determine T cell activation and tolerization in vivo. However, T cell activation was not apparent at any concentration of ionomycin, although a low dose of anti-CD3 monoclonal antibody (mAb) induced activation, while a high dose induced anergy in vitro. These results indicate that the balance between the Ca²⁺ signal and other signals which can also be induced by anti-CD3 stimulation, but not the actual intensity of the Ca²⁺ signal or the presence of co-stimulation, played an important role in regulating T cell activation and anergy.

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The components contributing to the antioxidative activity of supersweet corn powder (SSCP), which is commonly used in corn soup and snacks in Japan, were clarified and the effects investigated. 7-(O-β-Glucosyloxy)oxindole-3-acetic acid (GOA) was found to be the component most strongly contributing to the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity of the 80% ethanol extract of SSCP, and the presence of its aglycone, 7-hydroxy-oxindole-3-acetic acid (HOA) was confirmed. GOA and HOA respectively contributed 35.1% and 10.5% to the DPPH radical-scavenging activity of the 80% ethanol extract of SSCP. Mice orally administered with HOA at doses of both 500 and 1500 mg/kg showed a significantly lower (p<0.05) level of thiobarbituric acid reactive substances (TBARS) in the plasma than the vehicle-treated control. These results suggest that GOA and HOA were at least partly involved in the antioxidative activity of SSCP in vitro and that HOA might have possessed antioxidative activity in vivo.

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Despite ongoing intensive asthma research, the incidence of asthma is increasing worldwide. We investigated in this study the effects of Amomum compactum on ovalbumin (OVA)-induced asthma in a mouse model, and studied the possible mechanism for its anti-asthmatic action. Our data show that an A. compactum treatment markedly decreased the number of infiltrating eosinophils and the hypersecretion of mucus when compared with the effects on mice treated with OVA alone. The A. compactum treatment dose-dependently decreased the levels of reactive oxygen species (ROS) and T helper (Th)2 cytokines, including interleukin (IL)-4 and IL-5, in the bronchoalveolar lavage fluid (BALF), and a high dose of A. compactum effectively reduced the level of total immunoglobulin (Ig)E in the serum. Taken together, these data indicate that the administration of A. compactum may have potential therapeutic value when used as an adjuvant for the immunomodulatory treatment of allergic asthma.

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Metabolite profiling of Cheonggukjang inoculated with different Bacillus strains including Bacillus amyloliqueciens CH86-1, Bacillus licheniformis 58, and Bacillus licheniformis 67 during fermentation, was performed using gas chromatography-time of flight-mass spectrometry after derivatization, combined with multivariate statistical analysis. A total of 20 amino acids, 10 sugars, five sugar alcohols, and seven organic acids were identified in three Cheonggukjang samples. With fermentation time, most of the amino acids showed increasing amounts. On the other hand, most of the sugars including sucrose, fructose, and glucose decreasing patterns, and the amounts of organic acids varied. In order to observe differences in metabolites with fermentation time and inoculated Bacillus strains, principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were carried out, respectively. On PCA plots, some sugars and organic acids including sucrose, fructose, glucose, mannose, succinic acid, and malonic acid, as well as most of the amino acids, contributed mainly to differentiation of the Cheonggukjang samples fermentation time. On the other hand, on PLS-DA, mannose, xylose, glutamic acid, and proline were mainly responsible for differentiating the Cheonggukjang among into various inoculated strains.

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We conducted two randomized, placebo-controlled, double-blind studies of Lactobacillus plantarum No. 14 (LP14) in female students with seasonal allergic diseases. We also examined the mitogenic activity and cytokine inducibility of LP14 using Peyer’s patch cells and mesenteric lymph node cells of swine. For subjects who took 8.7×10⁸ of LP14, a significant improvement in ocular symptom-medication score was observed. In the placebo group, the T helper type 1 (Th1)/T helper type 2 (Th2) ratio tended to decrease after a 6-week intake period, while in the LP14 group, the percentage of Th1 cells significantly increased. Post-intake eosinophil counts significantly increased in comparison to those at intake cessation in the placebo group, but it appeared to be suppressed in the LP14 group. There were no changes in fecal microflora. LP14 strongly induced the gene expression of Th1-type cytokines. This study indicates the clinical effects of LP14 on seasonal allergic diseases.

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The oxidization of fatty acids generates many volatile compounds forming an aroma, but little is known whether mammals use gustatory sense to detect the oxidized products as a taste or only use olfactory sense to detect as an aroma. We examined in this study the effect of aqueous extracts of the compounds from autoxidized arachidonic acid (AA) ethyl ester or hexanal which is the predominant component generated from oxidized AA by the anosmic mouse licking performance to a tastant. The addition of the water extract from oxidized AA or hexanal to a quinine hydrochloride (QHCl) solution decreased the anosmic mice licking frequency at several concentrations of QHCl. Hexanal also reduced the licking frequency of anosmic mice conditioned to avoid MSG at several concentrations of monosodium glutamate (MSG). These results suggest that hexanal would affect mouse taste perception to QHCl and MSG via the gustatory sensation.

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We have reported that LG21 yogurt containing Lactobacillus gasseri OLL 2716 (LG21 yogurt) inhibits the formation of HCl-induced acute gastric lesions through the generation of prostaglandin E₂. This study aimed to determine the role of viable Lactobacillus in the healing of acetic acid-induced chronic gastric ulcer. LG21 yogurt or γ-ray radiated LG21 yogurt was administered orally twice a day for 10 d at a dose of 5 ml/kg. LG21 yogurt significantly accelerated the healing of the ulcer, but γ-ray radiated LG21 yogurt did not. However, both yogurts significantly inhibited HCl-induced gastric erosive lesions and enhanced the generation of gastric mucosal prostaglandin E₂. From the above results, it was found that viable bacteria are needed to accelerate the healing of chronic gastric ulcer, but not to inhibit gastric lesions.

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Food allergy was induced in two groups of NC/jic mice. Mice fed frucuto-oligosaccharides showed fewer allergic symptoms than control diet-fed mice. The cecal microbiota compositions were clearly different between the two groups, and the difference was partly attributable to Clostridia possession. A possible link of the compositional change in intestinal micriobiota with the anti-allergic effect of fructo-oligosaccharides is suggested.

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Global analysis of gene expression profiles in most-glycinin-deficient cultivar Tousan205, was performed by DNA microarray analysis. It was confirmed that Tousan205 lacks mRNA expression of three glycinin subunit precursor genes, G1 (A1aB1x), G2 (A2B1a), and G5 (A3B4), and lacks G4 (A5A4B3) protein. Most glycinin subunits were deficient in mature seeds of Tousan205. We compared the gene expression of Tousan205 with those of parent cultivar, Tamahomare, which was used for crossbreeding of Tousan205. As a result, Tousan205 exhibited higher expression of some seed maturation proteins, and stress-related genes such as glutathione S-transferase and ascorbate peroxidase. This result indicates the possibility that the decrease of main storage protein, glycinin causes stress in soybean.

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The xylitol dehydrogenase gene (xdh) of Bacillus pallidus was cloned and overexpressed in Escherichia coli using pQE60 vector, for the first time. The open reading frame of 759 bp encoded a 253 amino acid protein with a calculated molecular mass of 27,333 Da. The recombinant xylitol dehydrogenase (XDH) was purified to homogeneity by three-step column chromatography, producing a single SDS–PAGE band of 28 kDa apparent molecular mass. The enzyme exhibited maximal activity at 55 °C in glycine-NaOH buffer pH 11.0, with 66% of initial enzyme activity retained after incubation at 40 °C for 1 h. In further application of the recombinant bacterium to L-xylulose production from xylitol (initial concentration 5%) using a resting cell reaction, 35% L-xylulose was produced within 24 h. This result indicates that this recombinant XDH is applicable in the large-scale production of L-xylulose.

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A string-like carbon fiber was found to be very suitable as a working electrode material for direct electrochemical oxidation of β-nicotinamide adenine dinucleotide reduced form (NADH), and direct use of it for an enzyme reactor was possible. The electrochemical NAD⁺ recycling system was applied to glucose dehydrogenase (GDH) and to the recombinant formate dehydrogenase (RFDH) reactors. The maximum oxidation current value increased to 3.9 mA in the case of the GDH reactor. The remaining GDH activity after the reaction for 10 h amounted to 57% of the initial level. The remaining NAD⁺ activity amounted to 78% of the initial level. The current efficiency was calculated to be 80%. Furthermore, RFDH, which was more stable than GDH, was applied to the system. The maximum current value reached 5.9 mA. The remaining RFDH activity after reaction for 10 h amounted to 81% of the initial level. The remaining NAD⁺ activity was 78% of the initial level. The current efficiency was calculated to be 73%. Based on these results, both the enzyme and NAD⁺ were found to be acceptably stable in the electrochemical NAD⁺ recycling system.

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Root-associating bacteria of the nipa palm (Nypa fruticans), preferring brackish-water affected mud in Sarawak, Malaysia, were investigated. In a comparison of rhizobacterial microbiota between the nipa and the sago (Metroxylon sagu) palm, it was found that the nipa palm possessed a group of Burkholderia vietnamiensis as its main active nitrogen-fixing endophytic bacterium. Acetylene reduction by the various isolates of B. vietnamiensis was constant (44 to 68 nmol h⁻¹ in ethylene production rate) in soft gel medium containing 0.2% sucrose as sole carbon source, and the bacterium also showed motility and biofilm-forming capacity. This is the first report of endophytic nitrogen-fixing bacteria from nipa palm.

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