Bioscience, Biotechnology, and Biochemistry
Online ISSN : 1347-6947
Print ISSN : 0916-8451
Volume 73 , Issue 5
Showing 1-50 articles out of 51 articles from the selected issue
Award Review
Analytical Chemistry Regular Paper
  • MD. Azharul ISLAM, Rei YAMAKAWA, Nguyen Duc DO, Naoko NUMAKURA, Toshir ...
    2009 Volume 73 Issue 5 Pages 1156-1162
    Published: May 23, 2009
    Released: May 23, 2009
    [Advance publication] Released: May 07, 2009
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    Conjugated dienyl compounds make one of the main groups of lepidopteran sex pheromones, and GC has been frequently used to determine the configurations of the double bonds. However, the separation of two geometric isomers of a terminal-conjugated diene, such as 7,9-decadien-1-ol secreted by a nettle moth Parasa lepida lepida (Limacodidae), is assumed to be difficult. In order to clarify the chromatographic separation of the terminal dienes, 7,9-decadienyl and 9,11-dodecadienyl compounds (alcohols, acetates, and aldehydes) were analyzed by GC and HPLC. On a capillary GC column, the (E)-isomers flowed out slightly faster than the corresponding (Z)-isomers, but their peaks almost overlapped. On the other hand, HPLC equipped with an ODS column completely separated the two geometric isomers examined and the (Z)-isomers eluted from the column faster than the (E)-isomers without dependence on a functional group. In addition to undergoing direct HPLC analysis without derivatization, the dienyl alcohols were converted into 3,5-dinitrobenzoates and analyzed by LC-ESI-MS operated under the same reversed-phase condition. The two separated geometric isomers were sensitively monitored by negative ions at mz 211, M, M+1, M+17, and M+31, which were characteristically derived from the benzoates. Based on these results, a pheromone extract of P. l. lepida was examined, and it was confirmed that the female moths exclusively produced the (Z)-isomer of the 7,9-diene. Furthermore, a GC-EAD analysis and a field evaluation with both geometrical isomers indicated that the mating communication of P. l. lepida is predominantly mediated with the (Z)-isomer.
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Analytical Chemistry Note
  • Naoko INOUE, Yoshio SUZUKI, Kenji YOKOYAMA, Isao KARUBE
    2009 Volume 73 Issue 5 Pages 1215-1217
    Published: May 23, 2009
    Released: May 23, 2009
    [Advance publication] Released: May 07, 2009
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    A new reagent, N-[2-(diphenylphosphino)ethyl]-4-(1,3,5,7-tetramethyl-4,4-difluoro-4-bora-3a,4a-diaza-s-indacene-8-yl)benzamide (DPPEA-BODIPY), was designed and synthesized for analysis of hydroperoxides. DPPEA-BODIPY fluoresces at low levels in the visible range (λex⁄λem = 502 nm/515 nm) and reacts with hydroperoxides to produce DPPEA-BODIPY oxide, which fluoresces at high levels. The fluorescence intensity of the reaction mixture was observed to be linearly related to the methyl linoleate hydroperoxide (MeLOOH) concentration.
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Organic Chemistry Regular Papers
  • Daisuke ITO, Yosuke SHINKAI, Yuki KATO, Tadao KONDO, Kumi YOSHIDA
    2009 Volume 73 Issue 5 Pages 1054-1059
    Published: May 23, 2009
    Released: May 23, 2009
    [Advance publication] Released: May 07, 2009
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    To clarify the cause of the difference in blue and red color development of hydrangea sepals, Hydrangea macrophylla, we analyzed the organic and inorganic components in the colored cells. To obtain colored protoplasts, each blue and red sepal tissue was treated with a combination of cellulase and pectinase, and then from the suspension of the olored and colorless protoplast mixture colored cells of the same hue were collected with a micro-pipette. The content of organic components (delphinidin 3-glucoside, chlorogenic acid, neochlorogenic acid and 5-O-p-coumaroylquinic acid) and Al3+ in each colored cell was quantified respectively by semimicro-HPLC and graphite furnace atomic absorption spectroscopy (GFAAS). In the blue cells 13 eq. of 5-O-acylquinic acids and 1.2 eq. of Al3+ to anthocyanin were contained. Contrary to this result, in the red cells, only 3.6 eq. of 5-O-acylquinic acids and 0.03 eq. of Al3+ were detected. A reproduction experiment of each blue and red sepal color by mixing those components concluded that, for blue coloration, both 5-O-acylquinic acids and Al3+ were essential.
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  • Takasumi KASHIMA, Kosaku TAKAHASHI, Hideyuki MATSUURA, Kensuke NABETA
    2009 Volume 73 Issue 5 Pages 1118-1122
    Published: May 23, 2009
    Released: May 23, 2009
    [Advance publication] Released: May 07, 2009
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    The biosynthesis of lasiodiplodin (1) and its (5S)-5-hydroxylated derivative (2) were investigated by the administration of 13C-labeled acetates to Lasiodiplodia theobromae. The labeling patterns of biosynthetically 13C-labeled 1 and 2 were determined by 13C-NMR and INADEQUATE spectra, demonstrating the octaketide origins of 1 and 2. Taking into account the biosynthetic study of resorcylic acid lactones, the involvement of highly reduced acyl intermediates in the biosynthesis of lasiodiplodins was presumed; thus, we synthesized 2H-labeled hypothetical acyl intermediates of 1, 9-hydroxydecanoic acid (4) and its N-acetylcysteamine thioester (SNAC, 5). When L. theobromae was incubated with 5 mM of a 2H-labeled intermediate, the 2H-label from the intermediate was incorporated at the expected position of 1. These incorporation studies revealed that 1 was produced via a pathway which closely resembles that of resorcylic acid lactone biosynthesis.
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  • Kazuhiro CHIKU, Hirofumi DOHI, Akihiro SAITO, Hiroki EBISE, Yusuke KOU ...
    2009 Volume 73 Issue 5 Pages 1123-1128
    Published: May 23, 2009
    Released: May 23, 2009
    [Advance publication] Released: May 07, 2009
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    We have purified and characterized an oligoxylosyl transfer enzyme (OxtA) from Bacillus sp. strain KT12. In the present study, a N-terminally His-tagged recombinant form of the enzyme, OxtA(H)E, was overproduced in Escherichia coli and applied to the reaction with xylan and hydroquinone to produce 4-hydroxyphenyl β-D-oligoxylosides, β-(Xyl)n-HQ (n=1–4), by one step reaction. The obtained β-(Xyl)n-HQ inhibited mushroom tyrosinase, which catalyzes the oxidation of L-DOPA to L-DOPA quinine, and the IC50 values of β-Xyl-HQ, β-(Xyl)2-HQ, β-(Xyl)3-HQ, and β-(Xyl)4-HQ were 3.0, 0.74, 0.48, and 0.18 mM respectively. β-(Xyl)4-HQ showed 35-fold more potent inhibitory activity than β-arbutin (4-hydroxyphenyl β-D-glucopyranoside), of which the IC50 value was measured to be 6.3 mM. Kinetic analysis revealed that β-(Xyl)2-HQ, β-(Xyl)3-HQ, and β-(Xyl)4-HQ competitively inhibited the enzyme, and the corresponding Ki values were calculated to be 0.20, 0.29, and 0.057 mM respectively.
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Organic Chemistry Communication
  • Keiichi ODA, Megumi IMURA, Yoshimi UEDA, Miho HOSOKAWA, Michiyo KOBAYA ...
    2009 Volume 73 Issue 5 Pages 1233-1237
    Published: May 23, 2009
    Released: May 23, 2009
    [Advance publication] Released: May 07, 2009
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    Phospholipase D (PLD) is a biocatalyst in the synthesis of bioactive compounds and a key enzyme in a variety of biological signal transductions. A combination of unnatural phosphatidyl acceptor, N,N,N-triethyl-N-2-hydroxyethylammonium bromide 6, as a substrate for PLD, and tandem electrospray ionization mass spectrometry (ESI MS) was found to provide information as to whether a given phospholipid serves as a substrate for the PLD-catalyzed reaction. Thus 2-(13′-hydroperoxy-octadecadienoyl)-1-palmitoylglycerophosphocholine 1, and its degradation products 2-(13′-oxo-octadecadienoyl)-1-palmitoylglycerophosphocholine 9 and 2-(13′-hydroxy-octadecadienoyl)-1-palmitoylglycerophosphocholine 11, in a mixture were found to be a substrate of the PLD-catalyzed transphosphatidylation. The sensitivity of this method was exemplified by the observation that PLD activity in cabbage leaves was detected using a small amount of crude crushed leaves with little pretreatment. This simple method can be used in screening for PLD activity and searching for inhibitors of the enzyme from various natural sources.
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Biochemistry & Molecular Biology Regular Papers
  • Yasuhisa FUKUTA, Hidenobu KOMEDA, Yoichi YOSHIDA, Yasuhisa ASANO
    2009 Volume 73 Issue 5 Pages 980-986
    Published: May 23, 2009
    Released: May 23, 2009
    [Advance publication] Released: May 07, 2009
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    The genes encoding ω-laurolactam hydrolases from Cupriavidus sp. T7, Acidovorax sp. T31, Cupriavidus sp. U124, and Sphingomonas sp. U238 were cloned and sequenced. Nucleotide and amino acid sequence analysis of the four genes indicated that the primary structures of these ω-laurolactam hydrolases are significantly similar to the 6-aminohexanoate-cyclic-dimer hydrolase (EC 3.5.2.12). These genes were expressed in Escherichia coli, and the ω-laurolactam hydrolysing activity of the recombinant enzymes was compared with that of 6-aminohexanoate-cyclic-dimer hydrolase from Arthrobacter sp. KI72. The enzyme from Acidovorax sp. T31 was most successfully expressed in E. coli. Cell-free extract of the recombinant strain was used for the synthesis of 12-aminolauric acid from ω-laurolactam by “enzymatic transcrystallization,” because crystalline ω-laurolactam added into the enzyme solution was converted to crystalline 12-aminolauric acid (≧97.3% yield). Under the optimum conditions, 208 g/l of 12-aminolauric acid was produced in 17 h. The resulting pure product was identical to authentic 12-aminolauric acid.
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  • Alla SARAFEDDINOV, Susan SCHMIDT, Frank ADOLF, Martina MAINUSCH, Anne ...
    2009 Volume 73 Issue 5 Pages 993-999
    Published: May 23, 2009
    Released: May 23, 2009
    [Advance publication] Released: May 07, 2009
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    Transglutaminase (TGase) from Streptomyces mobaraensis is a Ca2+ independent enzyme that cross-links proteins to high molecular weight aggregates. A dispase autolysis inducing protein (DAIP) was identified as an intrinsic TGase substrate exhibiting accessible glutamine and lysine residues. DAIP modification during culture by TGase resulted in deamidation of reactive glutamines, formation of glutamic/lysine residue pairs, and failure of cross-linking. The reactivity of modified DAIP can be restored to some extent by N-lauroylamido-3-N′,N′-dimethylpropyl amine, thus exposing concertedly buried glutamines and lysines. The novel TGase substrate differs considerably from the well known Streptomyces subtilisin inhibitors in higher molecular mass (37 kDa), lower pI (7.1–7.2), moderate thermo-stability, and the mode of erasing dispase activity. Our experiments suggested that DAIP induces autolysis without removal of essential metals, such as Ca2+ and Zn2+. Among other endoproteases, only thermolysin was similarly affected, but at considerably higher DAIP concentrations, due to simultaneous degradation of DAIP.
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  • Fan-Jiang KONG, Ying LI, Jun ABE, Baohui LIU, Florian SCHALLER, Markus ...
    2009 Volume 73 Issue 5 Pages 1007-1013
    Published: May 23, 2009
    Released: May 23, 2009
    [Advance publication] Released: May 07, 2009
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    In previous reports we have reported that theobroxide induces characteristic accumulation of allene oxide cyclase (AOC; EC 5.3.99.6) protein and jasmonic acid (JA) in Pharbitis nil. In the present study, PnAOC, an AOC gene from Pharbitis nil was cloned. Immunofluorescence assays indicated that the AOC protein is located in the chloroplast of vascular bundles in Pharbitis nil leaves. The PnAOC cDNA sequence lacking the chloroplast signal peptide was successfully expressed in Escherichia coli, and a gas chromatography-mass spectrum assay suggested the relative AOC activity of the recombinant PnAOC protein in comparison with Arabidopsis AOC2. Interestingly, a biphasic expression of PnAOC was induced by theobroxide, which is consistent with the accumulation patterns of AOC protein and JA. All these results indicate that AOC is the primary target of theobroxide regulation and suggest that feedback regulation of PnAOC by JA occurs upon theobroxide treatment in Pharbitis nil.
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  • Yasuhiro TAKENAKA, Sachiko NAKANO, Masahiro TAMOI, Shohei SAKUDA, Tamo ...
    2009 Volume 73 Issue 5 Pages 1066-1071
    Published: May 23, 2009
    Released: May 23, 2009
    [Advance publication] Released: May 07, 2009
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    The expression levels of three chitinase genes in Arabidopsis thaliana, AtChiA (class III), AtChiB (class I), and AtChiV (class IV), were examined under various stress conditions by semi-quantitative RT-PCR. Under normal growth conditions, the AtChiB and AtChiV genes were expressed in most organs of Arabidopsis plants at all growth stages, whereas the AtChiA gene was not expressed at all. The class III AtChiA gene was expressed exclusively when the plants were exposed to environmental stresses, especially to salt and wound stresses. Treatment of Arabidopsis plants with allosamidin, which inhibits class III chitinases, did not affect the growth rate. Surprisingly, however, the plants treated with allosamidin were more tolerant of abiotic stresses (cold, freezing, heat, and strong light) than the control plants. It also appeared that allosamidin enhances AtChiA and AtChiB expression under heat and strong light stresses. Allosamidin is likely to enhance abiotic stress tolerance, probably through crosstalk between the two signaling pathways for biotic and abiotic stress responses.
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  • Zinnia RAHMAN, Yosuke SHIDA, Takanori FURUKAWA, Yota SUZUKI, Hirofumi ...
    2009 Volume 73 Issue 5 Pages 1083-1089
    Published: May 23, 2009
    Released: May 23, 2009
    [Advance publication] Released: May 07, 2009
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    One of the limiting factors for the application of Trichoderma reesei to degrade cellulosic biomass is its low β-glucosidase activity, required to convert cellobiose to glucose. The egl3 and the xyn3 promoters were used to express β-glucosidase 1 gene bgl1 through homologous recombination to improve the cellulose degradation ability of T. reesei. The recombinant strains expressing β-glucosidase 1 (BGLI) under the control of either the egl3 or the xyn3 promoter had 4.0 and 7.5 fold higher β-glucosidase activity than the native strain, which compares well to the finding that in wild-type T. reesei PC-3-7, the levels of egl3 and xyn3 mRNA expression were 6.0 and 12 fold higher respectively than that of bgl1. Matrix assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry analysis of proteins secreted by the recombinant strains demonstrated that BGLI was overproduced. The increase in the transcription of bgl1 and the concomitant elevated level of BGLI in these recombinant strains were sufficient to degrade the cellobiose and cellotriose formed during the degradation of pretreated cedar powder.
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  • Tomoko KITA, Shinsuke IMAI, Hiroshi SAWADA, Haruo SETO
    2009 Volume 73 Issue 5 Pages 1113-1117
    Published: May 23, 2009
    Released: May 23, 2009
    [Advance publication] Released: May 07, 2009
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    In addition to well-known curcuminoids, three colored metabolites were isolated from cultured cell clumps that had been induced from buds on turmeric rhizomes. The isolated compounds were identified as dihydro derivatives of curcuminoids, dihydrocurcumin (dihydroCurc), dihydrodesmethoxycurcumin-a (dihydroDMC-a), and dihydrobisdesmethoxycurcumin (dihydroBDMC). The cell clumps did not contain dihydroDMC-b, an isomer of dihydroDMC-a. A comparison of the distribution profiles of curcuminoids and dihydrocurcuminoids in the cell clumps with those in the rhizomes, leaves, and roots revealed the following differences: Unlike rhizomes, the cell clumps, leaves, and roots contained dihydrocurcuminoids as the major colored constituents. Whereas dimethoxy compounds, curcumin and dihydrocurcumin, respectively, were most abundant in the rhizomes and leaves, one of the monomethoxy derivatives, dihydroDMC-a, was found most abundantly in the cell clumps and roots. While both dihydroDMC-a and b were detected in the rhizomes, dihydroDMC-b was not detectable in the cell clumps, leaves, or roots. The occurrence of only one of the two possible isomers of dihydroDMC suggests biosynthetic formation of dihydrocurcuminoids in turmeric.
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  • Tomoshige HIRATSUKA, Nobuya ITOH, Haruo SETO, Tohru DAIRI
    2009 Volume 73 Issue 5 Pages 1137-1141
    Published: May 23, 2009
    Released: May 23, 2009
    [Advance publication] Released: May 07, 2009
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    In prokaryotes, menaquinone is used for respiration. In Escherichia coli, menaquinone is biosynthesized from chorismate by seven enzymes. However, very recently, we identified an alternative pathway (the futalosine pathway), which operates in some bacteria, including Streptomyces coelicolor, Helicobacter pylori, Campylobacter jejuni, and Thermus thermophilus. We describe the steps of this pathway, which branches at chorismate in a manner similar to the known pathway, but then follows a different route. This new pathway includes futalosine, an unusual nucleoside derivative consisting of inosine and o-substituted benzoate moieties, as a biosynthetic intermediate. In this study, a recombinant futalosine hydrolase (TTHA0556) of T. thermophilus, which participates in the second step of the pathway and catalyzes the reaction releasing hypoxanthine from futalosine, was prepared and used in functional analyses. Recombinant TTHA0556 formed a homotetramer and reacted only with futalosine; other structurally related nucleotides and nucleosides were not accepted. Recombinant TTHA0556 required no cofactors, and the optimum pH and temperature were 4.5 and 80 °C. The Km value was calculated to be 154.0±5.3 μM and the kcat value was 1.02/s. Recombinant TTHA0556 was slightly inhibited by hypoxanthine, with a Ki value of 1.1 mM.
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  • Wataru MATSUURA, Tomohiro YAMAZAKI, Yuko YAMAGUCHI-IWAI, Seiji MASUDA, ...
    2009 Volume 73 Issue 5 Pages 1142-1148
    Published: May 23, 2009
    Released: May 23, 2009
    [Advance publication] Released: May 07, 2009
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    The SLC39A family of zinc transporters can be divided into four subfamilies (I, II, LIV-1, and gufA) in vertebrates, but studies of their functions have been restricted exclusively to members of subfamilies II and LIV-1. In this study, we characterized SLC39A9 (ZIP9), the only member of subfamily I in vertebrates. Confocal microscopy demonstrated that transiently expressed, HA-tagged human ZIP9 (hZIP9-HA) was localized to the trans-Golgi network regardless of zinc status. Disruption of the ZIP9 gene in DT40 cells did not change the growth rate, sensitivity to high zinc and manganese concentrations during long-term culture, or cellular zinc status after short-term incubation with zinc. The alkaline phosphatase activity of ZIP9−⁄− cells did not change in cells cultured in medium containing normal zinc levels. In contrast, the activity of this enzyme decreased in wild-type cells cultured in zinc deficient medium but less so in ZIP9−⁄− cells under these conditions. Stable over-expression of hZIP9-HA moderately decreased alkaline phophatase activity. These results suggest that ZIP9 functions to regulate zinc homeostasis in the secretory pathway without significantly altering cytosolic zinc homeostasis.
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Biochemistry & Molecular Biology Notes
Food & Nutrition Science Regular Papers
  • Choong-Soo YUN, Hisakazu HASEGAWA, Hideaki NANAMIYA, Teruhiko TERAKAWA ...
    2009 Volume 73 Issue 5 Pages 1000-1006
    Published: May 23, 2009
    Released: May 23, 2009
    [Advance publication] Released: May 07, 2009
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    Phosphinothricin (PPT) is the active ingredient in bialaphos, which specifically inhibits glutamine synthetase in land plants. We isolated a novel PPT-resistant gene from a soil bacterium, Nocardia sp., and characterized it. The encoded protein, consisting of 177 amino acids, showed significant similarity to bacterial N-acetyltransferases, and we originally designated the gene MAT (methionine sulfone N-acetyltransferase). The recombinant MAT protein exhibited functions as a methionine sulfone and PPT N-acetyltransferase in vitro. The PPT N-acetyltransferase activity reached the maximum at pH 8–8.5, indicating that the protein might optimally function in chloroplasts. We therefore constructed a MAT gene, encoding the enzyme with a chloroplast-localizing signal in its amino-terminus. Plant transformation with the construct resulted in the generation of PPT-resistant rice and Arabidopsis. Furthermore, the transformed Arabidopsis was selectable in a synthetic medium containing PPT. The MAT gene thus facilitated establishment of herbicide-resistant plants, and as a new selectable gene marker.
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  • Gongliang ZHANG, Haitao WU, Beiwei ZHU, Yasuaki SHIMOISHI, Yoshimasa N ...
    2009 Volume 73 Issue 5 Pages 1014-1020
    Published: May 23, 2009
    Released: May 23, 2009
    [Advance publication] Released: May 07, 2009
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    Cellular phototoxicity induced by UVA irradiation and its potential application to therapy has been reported. In the present study, the induction of apoptosis induced by β-carotene and dimethyl tetrasulfide (Me2S4) assisted by UVA irradiation in HL-60 cells was assessed. β-carotene assisted by UVA significantly decreased the cell viability and induced DNA fragmentation in HL-60 cells. Me2S4 combined with β-carotene and assisted by UVA significantly inhibited the cell viability, and enhanced the caspase-3 activity which was completely inhibited by N-acety-L-cysteine. β-carotene was significantly degraded by UVA, but this was not accelerated by Me2S4 in a cell culture system. The photodegradation products of β-carotene prepared by UVA irradiation regardless of the addition of Me2S4 showed lower cytotoxicity than β-carotene itself in HL-60 cells. These results suggest that the ROS- and caspase-3-dependent apoptosis induced by β-carotene and Me2S4 assisted by UVA was due to a synergistic action rather than to the sole effect of the photodegradation products of β-carotene in HL-60 cells.
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  • Yukiko MASAMOTO, Fuminori KAWABATA, Tohru FUSHIKI
    2009 Volume 73 Issue 5 Pages 1021-1027
    Published: May 23, 2009
    Released: May 23, 2009
    [Advance publication] Released: May 07, 2009
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    The main aim of this study was to elucidate whether thermosensitive transient receptor potential channels (thermoTRPs) play a role in controlling autonomic thermoregulation. We investigated whether the activation of certain thermoTRPs, TRPV1, TRPV3, TRPM8, and TRPA1, would induce autonomic thermoregulation by administering chemical agonists derived from spices and aroma chemicals of these channels to anesthetized mice. We discovered the following: Capsaicin, a TRPV1 agonist, enhanced thermogenesis and heat diffusion; thymol and ethyl vanillin, TRPV3 agonists, did not have any effect on thermogenesis or heat diffusion; menthol and 1,8-cineole, TRPM8 agonists, enhanced thermogenesis; and allyl isothiocyanate and cinnamaldehyde, TRPA1 agonists, enhanced thermogenesis and inhibited heat diffusion. These results suggest that these thermoTRP agonists derived from spices and aroma chemicals modulate autonomic thermoregulation, except for TRPV3 agonists. Our findings suggest the possibility that each thermoTRP is a key sensor inducing reasonable autonomic thermoregulation according to its own activated temperature range.
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  • Orie YOSHINARI, Hideyo SATO, Kiharu IGARASHI
    2009 Volume 73 Issue 5 Pages 1033-1041
    Published: May 23, 2009
    Released: May 23, 2009
    [Advance publication] Released: May 07, 2009
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    The effects of a pumpkin paste concentrate and its components on oral glucose tolerance and serum lipid levels were determined in non-obese type 2 diabetic Goto-Kakizaki (GK) rats. In the oral glucose tolerance test, the pumpkin paste concentrate-fed group maintained a lower glucose level than the control group between 15 and 60 min. The compounds considered to be effective in improving glucose tolerance and contained in the methanol extract of the pumpkin in relatively abundant amounts were isolated and identified as trigonelline (TRG) and nicotinic acid (NA).
    Feeding a diet containing TRG and NA respectively improved and tended to improve glucose tolerance. The insulin level increased after 15 min in the TRG-fed GK rats and then gradually decreased over the next 120 min. In contrast, a gradual increase was seen in the insulin level over 120 min in the control GK rats not fed with TRG, suggesting that TRG could improve the insulin resistance. The serum and liver triglyceride (TG) levels in the TRG- and NA-fed GK rats were lower than those in the control GK rats. Lower activity of liver fatty acid synthase (FAS), and higher activity of liver carnitine palmitoyl transferase (CPT) and glucokinase (GLK) in the TRG- and NA-fed GK rats than in the control GK rats were observed. This suggests that the regulation of these enzyme activities by TRG and NA was closely related to the suppression of both TG accumulation and the progression of diabetes.
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  • Seung-Hyun KIM, Seung-Sik CHO, Jaya-Ram SIMKHADA, Hyo-Jeong LEE, Si-Wo ...
    2009 Volume 73 Issue 5 Pages 1048-1053
    Published: May 23, 2009
    Released: May 23, 2009
    [Advance publication] Released: May 07, 2009
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    Ginseng (Panax ginseng C.A. Meyer) has a wide range of therapeutic uses including cancer treatment. Human promyelocytic leukemia cells differentiate into monocytes or granulocytes when treated with 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3] or all-trans retinoic acid (ATRA). Treatment of HL-60 cells with zero to 100 μg/ml of a methanol extract of ginseng for 72 h induced a small increase in cell differentiation. Surprisingly, a synergistic induction of differentiation was observed when HL-60 cells were treated with ATRA or 1,25-(OH)2D3 and the extract. The inhibitors of protein kinase C (PKC) and extracellular signal-regulated kinase (ERK), but not of phosphoinositide 3-kinase (PI3-K), inhibited the HL-60 differentiation induced by the extract in combination with ATRA or 1,25-(OH)2D3, signifying that PKC and ERK were involved in the cell differentiation enhancement by the extract. These results suggest that the ability of a methanol extract of ginseng to enhance the differentiation potential of ATRA or 1,25-(OH)2D3 may improve the ultimate outcome of acute promyelocytic leukemia therapy.
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  • Yoshiaki AMAKURA, Morio YOSHIMURA, Naoki SUGIMOTO, Takeshi YAMAZAKI, T ...
    2009 Volume 73 Issue 5 Pages 1060-1065
    Published: May 23, 2009
    Released: May 23, 2009
    [Advance publication] Released: May 07, 2009
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    In order to establish the marker constituents of the natural antioxidant food-additive Eucalyptus leaf extract, the UV-absorbing constituents of two eucalyptus leaf extracts registered as food additives (eucalyptus A and B) were investigated. Several major peaks on the reversed-phase HPLC chromatogram of eucalyptus A were characterized as gallic acid, ellagic acid, 3-O-β-D-glucuronides of quercetin and kaempferol, and a hydrolyzable tannin dimer, oenothein B, by direct comparison with authentic specimens isolated from Eucalyptus globulus leaves. A new gallotannin was found in the E. globulus leaf extract, and its structure was found to be 1,2,3,6-tetra-O-galloyl-β-D-galactose. Two major peaks on the HPLC chromatogram of eucalyptus B were identified as gallic acid and ellagic acid, indicative of degradation products from hydrolyzable tannins in the leaves. Considering the evaluation of antioxidant activity by radical scavenging ability, a standardization of eucalyptus leaf extract, including the antioxidative polyphenol, oenothein B, is proposed.
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  • Kyoji YOSHINO, Yuko MIYAUCHI, Takashi KANETAKA, Yasutaka TAKAGI, Kunim ...
    2009 Volume 73 Issue 5 Pages 1096-1104
    Published: May 23, 2009
    Released: May 23, 2009
    [Advance publication] Released: May 07, 2009
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    The effects of a water extract prepared from the leaves of Salacia reticulata on the absorption of sugars in normal and type 1 diabetic mice were investigated. The simultaneous oral administration of the extract at a dose of 1.0 mg/mouse with maltose or sucrose inhibited the postprandial elevation of the plasma glucose and insulin levels and intestinal α-glucosidase activities in mice. In addition, the supply of a 0.01% solution of the extract as drinking water prevented the elevation of the plasma glucose level and intestinal α-glucosidase activities in type 1 diabetic mice. This treatment also prevented the elevation of the plasma, pancreatic, and kidney lipid peroxide levels, lowering of the plasma insulin level, and elevation of the kidney aldose reductase activities in diabetic mice. These results suggest that the water extract of the leaves of S. reticulata could be a beneficial food material for the prevention of diabetes and obesity because of its multiple effects.
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  • Jae Kyeom KIM, Heyri BAE, Mi-Jeong KIM, Soo Jung CHOI, Hong Yon CHO, H ...
    2009 Volume 73 Issue 5 Pages 1105-1112
    Published: May 23, 2009
    Released: May 23, 2009
    [Advance publication] Released: May 07, 2009
    JOURNALS FREE ACCESS
    Various native Korean plants were screened to find an effective acetylcholinesterase (AChE) inhibitor for the treatment of Alzheimer’s disease (AD). Among these plants, the ethanol extract of Poncirus trifoliate was selected for isolating the AChE inhibitor because it exhibited the highest inhibitory activity (47.31%). To separate the active compound from Poncirus trifoliate, solvent partition, open column chromatography, thin-layer chromatography (TLC), and high-performance liquid chromatography (HPLC) were utilized. The putative chemical structure of the AChE inhibitor was identified as methoxsalen by successive analysis with electron ionization mass spectrometry (EI-MS) and 13C/1H-nuclear magnetic resonance (NMR). To confirm the attenuating effect of the Poncirus trifoliate extract against trimethyltin (TMT)-induced neurotoxicity, in vivo behavior tests were carried out. Our findings suggest that the Poncirus trifoliate extract significantly reversed TMT-induced learning and memory impairment. These results demonstrate that the Poncirus trifoliate extract could possess a wide range of beneficial activities for neurodegenerative disorders, notably AD.
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  • Rong-Rong HE, Xin-Sheng YAO, Nan YAO, Min WANG, Yi DAI, Hao GAO, Yang ...
    2009 Volume 73 Issue 5 Pages 1129-1136
    Published: May 23, 2009
    Released: May 23, 2009
    [Advance publication] Released: May 07, 2009
    JOURNALS FREE ACCESS
    We investigated the effects of an extract of Radix Rosa laevigata (R. R. laevigata) on Propionibacterium acnes (P. acnes) and lipopolysaccharide (LPS)-induced acute liver injury. The plasma alanine aminotransferase (ALT) activity was significantly elevated by an intravenous injection of heat-killed P. acnes at a dose of 0.4 mg/mouse and then with LPS at 0.1 μg/mouse after 5 d. However, the elevated ALT activity was significantly reduced by the administered of R. R. laevigata (125 and 500 mg/kg/d) for 7 d before the LPS injection. In addition, the extract treatment reduced the number of liver mononuclear cells (MNCs), and malondialdehyde (MDA) and nitric oxide (NO) contents, but improved the liver oxygen radical absorbance capacity (ORAC) and mitochondrial membrane potential. Moreover, the chemical profile of R. R. laevigata was performed by high-performance liquid chromatography (HPLC) and the main peaks were identified as a series of polyphenol compounds which had been confirmed as the significantly active components by their anti-oxidative and NO inhibitory effects. These results suggest that the extract of R. R. laevigata offered good efficacy for preventing liver injury.
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Food & Nutrition Science Notes
Microbiology & Fermentation Technology Regular Papers
  • Angkana SAIKEUR, Wanna CHOORIT, Poonsuk PRASERTSAN, Duangporn KANTACHO ...
    2009 Volume 73 Issue 5 Pages 987-992
    Published: May 23, 2009
    Released: May 23, 2009
    [Advance publication] Released: May 07, 2009
    JOURNALS FREE ACCESS
    5-Aminolevulinic acid (ALA) and the biomass of photosynthetic bacteria, Rhodopseudomonas palustris KG31, have very high potential for development and exploitation as bioherbicide and biofertilizer respectively. In this work, the effects of two precursors and an inhibitor of aminolevulinic dehydratase (ALAD) added to the VFA culture medium on the production of ALA and biomass were investigated. The experimental runs were carried out according to a Box-Behnken design. The precursors were added to the medium at the beginning of cultivation, while the inhibitor was added after 24 h. Statistical analysis indicated that levulinic acid (LA) has a positive effect on ALA production while glycine has a negative effect on biomass production. In order to enhance both ALA and biomass products, the most suitable medium was VFA medium supplemented with 3.0 mM glycine and 10 mM LA, giving ALA and biomass of 182.91 μM and 3.1 gDCW/l within 54 h.
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  • Yuko ARAKI, Shuichi KARITA, Akiyoshi TANAKA, Makoto KONDO, Masakazu GO ...
    2009 Volume 73 Issue 5 Pages 1028-1032
    Published: May 23, 2009
    Released: May 23, 2009
    [Advance publication] Released: May 07, 2009
    JOURNALS FREE ACCESS
    The endoglucanase Cel5A from an anaerobic celluloltyic bacterium, Clostridium josui, contains family 17 CBM (CjCBM17) and family 28 CBM (CjCBM28) in tandem. Individual CjCBM17 and CjCBM28 and tandem CjCBM17/28 were constructed to determine the binding characteristics of CjCBM17/28 and to compare the binding affinity of the three CBMs. CjCBM17/28 bound to non-crystalline cellulose, soluble cellulose derivatives, and oat-spelt xylan, but not to birchwood xylan or starch. The thermodynamic parameters for the binding of the CBMs with cellooligosaccharides were determined by isothermal titration calorimetry. The binding of CjCBM28 to cellotetraose and cellopentaose was enthalpically driven (large negative ΔH value), while that of CjCBM17 was entropically driven (positive ΔS value). These two CBMs had different mechanisms for binding to cellooligosaccharides. They showed similar binding constants (Ka) for cellopentaose, but in the case of insoluble polysaccharides, the Ka of CjCBM17/28 was approximately 3–7 times higher than that of individual CBMs.
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  • Toshitsugu SATO, Katsuhiro KANDA, Kumiko OKAWA, Machiko TAKAHASHI, His ...
    2009 Volume 73 Issue 5 Pages 1042-1047
    Published: May 23, 2009
    Released: May 23, 2009
    [Advance publication] Released: May 07, 2009
    JOURNALS FREE ACCESS
    The gill browning of Lentinula edodes fruit-bodies during preservation is thought to be due to melanin biosynthesis catalyzed by tyrosinase. We isolated a genomic DNA sequence and cDNA encoding a putative tyrosinase from the white rot basidiomycete Lentinula edodes (shiitake mushroom). The gene, named Letyr, consists of a 1,854-bp open reading frame interrupted by eight introns, and encodes a putative protein of 618 amino acid residues with an estimated molecular mass of 68 kDa. Amino acid residues known to be involved in copper-binding domains were conserved in the deduced amino acid residues of LeTyr. Transcriptional and translational expression of Letyr in the gills of the fruit-body increased during preservation after harvest. This correlation between Letyr expression and fruit-body preservation suggests that tyrosinase gene expression contributes to gill browning.
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  • Jeung-yil PARK, Tomoko SEYAMA, Riki SHIROMA, Masakazu IKE, Sathaporn S ...
    2009 Volume 73 Issue 5 Pages 1072-1077
    Published: May 23, 2009
    Released: May 23, 2009
    [Advance publication] Released: May 07, 2009
    JOURNALS FREE ACCESS
    Soft carbohydrates, defined as readily-recoverable carbohydrates via mere extraction from the biomass or brief enzymatic saccharification, were found in significant amounts in rice straw as forms of free glucose, free fructose, sucrose, starch, and β-1,3-1,4-glucan. In this study, we investigated their amounts in rice straw (defined as culm and leaf sheath), and developed an easy method for glucose and fructose recovery from them with heat-pretreatment and subsequent 4-h enzymatic saccharification with an enzyme cocktail of cellulase and amyloglucosidase. The recovery of glucose and fructose exhibited good correlation with the amounts of soft carbohydrates. The maximum yields of glucose and fructose in the rice straw per dry weight at the heading stage and the mature stage were 43.5% in cv. Habataki and 34.1% in cv. Leafstar. Thus, rice straw with soft carbohydrates can be regarded as a novel feedstock for economically feasible production of readily-fermentable glucose and fructose for bioethanol.
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  • Naoya KOIZUMI, Sumiko MASUDA, Kiyoe MAEDA, Yuya ISODA, Rie YATSUNAMI, ...
    2009 Volume 73 Issue 5 Pages 1078-1082
    Published: May 23, 2009
    Released: May 23, 2009
    [Advance publication] Released: May 07, 2009
    JOURNALS FREE ACCESS
    β-1,3-Glucanase (BglF) from Nocardiopsis sp. F96 is composed of only a catalytic domain. To improve the enzymatic properties of BglF, we attempted to construct chimeric enzymes consisting of BglF and some carbohydrate-binding modules, such as the C-terminal additional domain (CAD) and the N-terminal additional domain (NAD) of β-1,3-glucanase H from Bacillus circulans IAM1165 and the chitin-binding domain (ChBD) of chitinase from alkaliphilic Bacillus sp. J813. CAD-fused BglF (BglF-CAD), NAD-fused BglF (NAD-BglF), both NAD- and CAD-fused BglF (NAD-BglF-CAD) and ChBD-fused BglF (BglF-ChBD) were constructed and characterized. The addition of CAD caused increases in binding abilities and hydrolytic activities toward insoluble β-1,3-glucans. As well as BglF-CAD, the binding ability and hydrolytic activity of BglF-ChBD toward pachyman were also increased. The hydrolytic activity of BglF-CAD at pH 9–10 was higher than that of BglF. The relative activities of BglF-CAD and BglF-ChBD at around 50–70 °C were higher than that of BglF.
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  • Sanom NONKLANG, Akihiko ANO, Babiker M. A. ABDEL-BANAT, Yuko SAITO, Hi ...
    2009 Volume 73 Issue 5 Pages 1090-1095
    Published: May 23, 2009
    Released: May 23, 2009
    [Advance publication] Released: May 07, 2009
    JOURNALS FREE ACCESS
    Flocculating yeasts are highly useful in fermentation processes because these cells can be separated easily from the fermentation mash. However, native yeasts are usually non-flocculating, including Kluyveromyces marxianus, which exhibits a potent high-temperature ethanol fermentation ability. We describe here the construction of flocculent K. marxianus strains via the introduction of the FLO1, FLO5, FLO9, and FLO10 genes from Saccharomyces cerevisiae. The S. cerevisiae FLO genes were overexpressed by upstream insertion of the constitutive TDH3 promoter, resulting in flocculent S. cerevisiae strains. These TDH3p-FLO sequences were then amplified by PCR and introduced directly into a K. marxianus strain. These K. marxianus strains showed a flocculation phenotype, indicating that the introduced S. cerevisiae TDH3 promoter and all FLO genes were functional in this strain. Moreover, a flocculating K. marxianus strain showed the same ethanol production profile as that of its wild-type parent. The K. marxianus flocculating strains we generated should be useful in the future development of cost-effective fed-batch and continuous fermentation systems at high temperatures.
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  • Keitarou KIMURA, Lam-Son Phan TRAN, Thi-Huyen DO, Yoshifumi ITOH
    2009 Volume 73 Issue 5 Pages 1149-1155
    Published: May 23, 2009
    Released: May 23, 2009
    [Advance publication] Released: May 07, 2009
    JOURNALS FREE ACCESS
    An industrial strain of Bacillus subtilis (natto) was used to produce poly-gamma-DL-glutamate (γPGA), a polymer of DL-glutamate linked by a γ-peptide bond. In spite of efforts to improve γPGA production by modifying the medium, little attention has been paid to the expression of the γPGA synthetase gene. In this study, we investigated the expression of the γPGA synthetic gene and the γPGA product under various conditions with the LacZ-fusion of the synthetic gene (pgsB-lacZ). The 5′ upstream regulatory region of the pgsB gene was also investigated by constructing deletion mutations of lacZ-fusion. The pgsB-lacZ was clearly expressed in the early stationary phase and was abolished by degU gene disruption. The results showed that pgsB-lacZ expression was repressed in rich media, and that γPGA production was limited by the substrate supply rather than by the amount of synthetase. Adding D-glutamate to the medium reduced γPGA production and synthetic gene expression. The transcription start point was determined by primer extension, and it was found that up to −721 bp (translation start point = +1) of the 5′ untranslated region (UTR) was required for optimal pgsB-lacZ fusion gene expression.
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  • Makusu TSUIZAKI, Norio TAKESHITA, Akinori OHTA, Hiroyuki HORIUCHI
    2009 Volume 73 Issue 5 Pages 1163-1167
    Published: May 23, 2009
    Released: May 23, 2009
    [Advance publication] Released: May 07, 2009
    JOURNALS FREE ACCESS
    Chitin is one of the major cell wall components of ascomycete filamentous fungi, and chitin synthesis plays important roles in the morphogenesis of hyphae. In the Aspergillus nidulans genome, there are two genes, csmA and csmB, that encode a myosin motor-like domain (MMD) at their N-termini and a chitin synthase domain (CSD) at their C-termini. In our previous studies, we found that the MMD of CsmA was required for its functionality, and that CsmA and CsmB had certain overlapping functions essential for polarized filamentous growth. In this study, we constructed a strain that produced CsmB lacking the MMD (CSΔMB). This strain exhibited defects similar to those of the csmB deletion mutant. FLAG-tagged CSΔMB (CSΔMB-FLAG) did not properly localize to the hyphae. CsmB was co-immunoprecipitated with actin in vivo, whereas CSΔMB was not. These results suggest that the MMD of CsmB is crucial for its proper localization via interaction with actin.
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Microbiology & Fermentation Technology Notes
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