Bioscience, Biotechnology, and Biochemistry
Online ISSN : 1347-6947
Print ISSN : 0916-8451
Volume 76, Issue 4
Displaying 1-42 of 42 articles from this issue
Analytical Chemistry Regular Paper
  • Yosuke HANAI, Ken SHIMONO, Koichi MATSUMURA, Anil VACHANI, Steven ALBE ...
    2012 Volume 76 Issue 4 Pages 679-684
    Published: April 23, 2012
    Released on J-STAGE: April 23, 2012
    Advance online publication: April 07, 2012
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    Lung cancer is a leading cause of deaths in cancer. Hence, developing early-stage diagnostic tests that are non-invasive, highly sensitive, and specific is crucial. In this study, we investigated to determine whether biomarkers derived from urinary volatile organic compounds (VOCs) can be used to discriminate between lung cancer patients and normal control patients. The VOCs were extracted from the headspace by solid-phase microextraction and were analyzed by gas chromatography time-of-flight mass spectrometry. Nine putative volatile biomarkers were identified as elevated in the lung cancer group. Receiver operating characteristic curve analysis was also performed, and the markers were found to be highly sensitive and specific. Next we used principal component analysis (PCA) modeling to make comparisons compare within the lung cancer group, and found that 2-pentanone may have utility in differentiating between adenocarcinoma and squamous cell carcinomas.
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Organic Chemistry Regular Papers
  • Toshiya MASUDA, Tomoko INOUCHI, Aya FUJIMOTO, Yoshimi SHINGAI, Miyuki ...
    2012 Volume 76 Issue 4 Pages 705-711
    Published: April 23, 2012
    Released on J-STAGE: April 23, 2012
    Advance online publication: April 07, 2012
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    The functionality of spring mountain herbs, which were collected in the Kajigamori mountain area of Shikoku area in Japan, was investigated in the course of our studies for utilizing local plant resources. The radical scavenging activity of the extracts from seventeen herbs was measured. Among these herbs, two extracts from Polystichym ovato-paleaceum (Japanese name: Tsuyanashiinode) and Sambucus racemosa subsp. sieboldiana (Japanese name: Niwatoko) showed potent DPPH radical scavenging activity. The material evidence for the potent activity of the extracts was studied by a combination of our developed method for detecting antiradical compounds, LC-MS/MS, and enzymatic hydrolysis.
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  • Hideo HAYASHI, Yuki OKA, Kenji KAI, Kohki AKIYAMA
    2012 Volume 76 Issue 4 Pages 745-748
    Published: April 23, 2012
    Released on J-STAGE: April 23, 2012
    Advance online publication: April 07, 2012
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    The new meroterpenoid, chrodrimanin C (3), together with chrodrimanins A (2) and B (1) were isolated from okara (the insoluble residue of whole soybean) that had been fermented with strain YO-2 of Talaromyces sp. Their structures were elucidated by spectroscopic methods. The partial structures of 1 essential for exhibiting insecticidal activity were investigated by using a silkworm assay. The absolute configuration of 1 was also determined.
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  • Ryohei YAMASAKI, Kaori NAGAHARA, Katsuya KISHIMOTO, Akihiko TAKAJYO
    2012 Volume 76 Issue 4 Pages 772-777
    Published: April 23, 2012
    Released on J-STAGE: April 23, 2012
    Advance online publication: April 07, 2012
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    Glycosylation of penta-O-acetyl heptopyranosyl trichloroacetimidate with the 3-OH acceptor, methyl 2-O-benzyl-4,6-O-benzylidene-7,8-dideoxy-α-D-manno-oct-7-enopyranoside, gave the desired α1-3-linked disaccharide in a 94% yield. The oct-enopyranoside moiety of the disaccharide was converted to the heptoside by oxidative cleavage with osmium tetroxide/NaIO4 and subsequent reduction with NaBH4. The resulting α1-3-linked heptose disaccharide was converted to a tricholoroacetaimidate derivative containing a benzoyl group at C-2. This donor was glycosylated with 2-(carbobenzoxyamino)-1-ethanol to give an α spacer-linked disaccharide derivative in a 90% yield. Zemplén deacylation of the derivative and subsequent hydrogenolysis gave a 2-aminoethyl glycoside of heptopyranosyl(α1-3)heptopyranose.
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  • Yuan QU, Kaiyue SUN, Lijuan GAO, Youji SAKAGAMI, Hirokazu KAWAGISHI, M ...
    2012 Volume 76 Issue 4 Pages 791-793
    Published: April 23, 2012
    Released on J-STAGE: April 23, 2012
    Advance online publication: April 07, 2012
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    Two new cerebrosides, termitomycesphins G and H, were isolated from the edible Chinese mushroom, Termitomyces albuminosus (Berk.) Herm., and exhibited neuritogenic activity against PC12 cells. Their structures and absolute stereochemistry were elucidated by spectroscopic methods and by a comparison of the specific rotation of the hydrogenated products from termitomycesphins H and C. These cerebrosides possessed a unique modification by a hydroxyl group at the middle of the long-chain base, like earlier congeners termitomycesphins A–F. Termitomycesphin G with a 16-carbon-chain fatty acid showed higher neuritogenic activity than that of termitomycesphin H with an 18-carbon-chain fatty acid. This effect was observed within the termitomycesphins, suggesting that the chain length of the fatty acyl moiety played a key role in the neuritogenic activity.
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Organic Chemistry Notes
Biochemistry & Molecular Biology Regular Papers
  • Kaiyue SUN, Lan XIANG, Satoru ISHIHARA, Akira MATSUURA, Youji SAKAGAMI ...
    2012 Volume 76 Issue 4 Pages 640-645
    Published: April 23, 2012
    Released on J-STAGE: April 23, 2012
    Advance online publication: April 07, 2012
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    This study used a replicative lifespan assay of K6001 yeast to screen anti-aging food factors in commercial flavonoids. Hesperidin derived from the Citrus genus extended the lifespan of yeast at doses of 5 and 10 μM as compared with the control group (p<0.01, p<0.01). Reactive oxygen species (ROS), real-time PCR (RT-PCR), and lifespan assays of uth1 and skn7 mutants with the K6001 background were used to study the anti-aging mechanisms in yeast. The results indicate that hesperidin significantly inhibits the ROS of yeast, and UTH1 gene expression, and that SKN7 gene are involved in hesperidin-mediated lifespan extension. Further, increases in the Sir2 homolog, SIRT1 activity, and SOD gene expression were confirmed at doses of 5 (p<0.01) and 10 μM (p<0.05). This suggests that Sir2, UTH1 genes, and ROS inhibition after administration of hesperidin have important roles in the anti-aging effects of yeast. However, the aglycon hesperetin did not exhibit anti-aging effects in yeast.
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  • Takaaki KUBOTA, Yoshikazu IZUMI
    2012 Volume 76 Issue 4 Pages 685-690
    Published: April 23, 2012
    Released on J-STAGE: April 23, 2012
    Advance online publication: April 07, 2012
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    By detailed BLAST searches of the genome database of various thermophiles, five ORFs with similarity to the bioF gene, which encodes 7-keto-8-aminopelargonic acid synthase (BioF) involved in biotin biosynthesis, of Escherichia coli were found: AqbioF, CltbioF, GkbioF, SytbioF, and TsebioF, from Aquifex aeolicus VF5, Clostridium thermocellum ATCC27405, Geobacillus kaustophilus JCM12893, Symbiobacterium thermophilum IAM14863, and Thermosynechococcus elongatus BP-1 respectively. The five purified recombinant bioF gene products, which were overexpressed in E. coli, had the enzyme activity of BioF. The optimum temperature range and thermostability of five BioFs, AqBioF, CltBioF, GkBioF, SytBioF, and TseBioF, were higher than those of E. coli BioF. In particular, AqBioF was found to show the highest thermostability of the α-oxoamine synthase family enzymes reported to date. Substrate specificity experiments revealed that SytBioF was also able to catalyze the reaction of 2-amino-3-ketobutyrate CoA ligase, a member of the α-oxoamine synthase family, and that it used acetyl-CoA and glycine as substrates, like the TTHA1582 protein of Thermus thermophilus. The other purified BioFs, AqBioF and GkBioF, did not show any activity with acyl-CoAs and amino acids other than pimeloyl-CoA and L-alanine as substrates.
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  • Shunsuke KAWAMURA, Gen TOSHIMA, Yuki CHIJIIWA, Takao TORIKATA, Tomohir ...
    2012 Volume 76 Issue 4 Pages 691-698
    Published: April 23, 2012
    Released on J-STAGE: April 23, 2012
    Advance online publication: April 07, 2012
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    The amino acid sequence of Egyptian goose lysozyme (EGL) from egg-white and its enzymatic properties were analyzed. The established sequence had the highest similarity to wood duck lysozyme (WDL) with five amino acid substitutions, and had eighteen substitutions difference from hen egg-white lysozyme (HEL). Tyr34 and Gly37 were found at subsites E and F of the active site when compared with HEL. The experimental time-course characteristics of EGL against the N-acetylglucosamine pentamer substrate, (GlcNAc)5, revealed higher production of (GlcNAc)4 and lower production of (GlcNAc)2 when compared with HEL. The saccharide-binding ability of subsites A–C in EGL was also found to be weaker than in HEL. An analysis of the enzymatic reactions of five mutants in respect of positions 34, 37 and 71 in HEL indicated the time-course characteristics of EGL to be caused by the combination of three substitutions (F34Y, N37G and G71R) between HEL and EGL. A computer simulation of the EGL-catalyzed reaction suggested that the time-course characteristics of EGL resulted from the difference in the binding free energy for subsites A, B, E and F and the rate constant of transglycosylation between EGL and HEL.
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  • Qianglai TAN, Hengyi XU, Tingtao CHEN, Peng LI, Zoraida P. AGUILAR, Di ...
    2012 Volume 76 Issue 4 Pages 699-704
    Published: April 23, 2012
    Released on J-STAGE: April 23, 2012
    Advance online publication: April 07, 2012
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    Bifidobacterium is well known to have an inhibitory effect on the survival, growth, and proliferation of various foodborne pathogens, but the mechanism of the molecular action of B. longum in blocking the invasion of Listeria monocytogenes is not yet well defined. In the present study, following RNA extraction and cDNA synthesis, differential expression of virulence and stress fitness genes in L. monocytogenes and B. longum was determined by real-time PCR. The results indicate that L. monocytogenes virulence factors, including actA, hly, inlA, and plcA, showed significantly downregulated expression during co-incubation of B. longum and L. monocytogenes in phosphate-buffered saline. The relative mRNA levels of oppA and serpin, two stress fitness genes in B. longum, were significantly higher than for the control group. These results indicate that downregulation of L. monocytogenes virulence factors during co-incubation with B. longum might be responsible for the inhibitory effects.
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  • Tamar JAPARIDZE, Akitsugu SENDA, Hirofumi NOZAKI, Mayumi YANAGIDA, Tak ...
    2012 Volume 76 Issue 4 Pages 712-720
    Published: April 23, 2012
    Released on J-STAGE: April 23, 2012
    Advance online publication: April 07, 2012
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    A bovine lipocalin, previously identified as a putative odorant-binding protein in bovine colostrum (bcOBP), was cloned and expressed, and its monoclonal antibody was established. bcOBP was constantly secreted into milk on day of parturition until at least 10 d postpartum at a concentration of 181±39 μg/L. Besides milk, bcOBP occurred in the nasal mucus, saliva, amniotic fluid, vaginal discharge, and blood plasma. Despite its low concentration, the distribution pattern and the finding that bcOBP harbored a characteristic sequence motif, CxxxC, which is conserved among insect and mammal pheromone binding proteins, suggest that bcOBP functions as a pheromone carrier. The presence of bcOBP in the plasma at varied concentrations depending on the lactation period does not exclude the possibility that bcOBP is secreted into milk from the blood. Cross-reactivity of the monoclonal antibody indicated presence of proteins homologous to bcOBP in the colostrum of farm animals of Cetartiodactyla.
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  • Keiji TSUSAKI, Hikaru WATANABE, Takuo YAMAMOTO, Tomoyuki NISHIMOTO, Hi ...
    2012 Volume 76 Issue 4 Pages 721-731
    Published: April 23, 2012
    Released on J-STAGE: April 23, 2012
    Advance online publication: April 07, 2012
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    Highly branched α-glucan molecules exhibit low digestibility for α-amylase and glucoamylase, and abundant in α-(1→3)-, α-(1→6)-glucosidic linkages and α-(1→6)-linked branch points where another glucosyl chain is initiated through an α-(1→3)-linkage. From a culture supernatant of Paenibacillus sp. PP710, we purified α-glucosidase (AGL) and α-amylase (AMY), which were involved in the production of highly branched α-glucan from maltodextrin. AGL catalyzed the transglucosylation reaction of a glucosyl residue to a nonreducing-end glucosyl residue by α-1,6-, α-1,4-, and α-1,3-linkages. AMY catalyzed the hydrolysis of the α-1,4-linkage and the intermolecular or intramolecular transfer of maltooligosaccharide like cyclodextrin glucanotransferase (CGTase). It also catalyzed the transfer of an α-1,4-glucosyl chain to a C3- or C4-hydroxyl group in the α-1,4- or α-1,6-linked nonreducing-end residue or the α-1,6-linked residue located in the other chains. Hence AMY was regarded as a novel enzyme. We think that the mechanism of formation of highly branched α-glucan from maltodextrin is as follows: α-1,6- and α-1,3-linked residues are generated by the transglucosylation of AGL at the nonreducing ends of glucosyl chains. Then AMY catalyzes the transfer of α-1,4-chains to C3- or C4-hydroxyl groups in the α-1,4- or α-1,6-linked residues generated by AGL. Thus the concerted reactions of both AGL and AMY are necessary to produce the highly branched α-glucan from maltodextrin.
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  • Ali JAHANIAN-NAJAFABADI, Saeid BOUZARI, Mana OLOOMI, Mehryar HABIBI RO ...
    2012 Volume 76 Issue 4 Pages 749-754
    Published: April 23, 2012
    Released on J-STAGE: April 23, 2012
    Advance online publication: April 07, 2012
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    Immunotoxins are fusion proteins consisting of two elements, a targeting and a toxin moiety, and are designed for specific elimination of tumor cells. Previously we expressed a recombinant fusion protein consisting of the toxic fragment of Shiga toxin (A1) and GMCSF (A1-GMCSF) in Escherichia coli, and evaluated its cytotoxic properties in acute myeloid leukemia and colon carcinoma cell lines. In view of the specific cytotoxic effects of this immunotoxin, further detailed in-vitro and preclinical studies were undertaken. Large amounts of the recombinant protein of high purity and free of unwanted side products, such as lipopolysaccharides (LPS), were required. Since GMCSF is of mammalian origin and it requires proper disulfide bond formation, we intended to use the baculovirus expression vector system (BEVS) for the expression of the recombinant fusion protein. However, despite previous reports on the expression of several other immunotoxins by this system, the A1 derived fusion proteins revealed an inhibitory effect on baculoviral particle formation and even caused cell death in insect cells. This observation was further pursued and confirmed by the use of other baculoviral specific promoters. The salient features of this finding are described below.
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  • Takayasu KAWASAKI, Shunsuke KAMIJO
    2012 Volume 76 Issue 4 Pages 762-766
    Published: April 23, 2012
    Released on J-STAGE: April 23, 2012
    Advance online publication: April 07, 2012
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    Supplementary material
    Aggregations of proteins are in many cases associated with neurodegenerative diseases such as Alzheimer’s (AD). Small compounds capable of inhibiting protein aggregation are expected to be useful for not only in the treatment of disease but also in probing the structures of aggregated proteins. In previous studies using phage display, we found that arginine-rich short peptides consisting of four or seven amino acids bound to soluble 42-residue amyloid β (Aβ42) and inhibited globulomer (37/48 kDa oligomer) formation. In the present study, we searched for arginine-containing small molecules using the SciFinder searching service and tested their inhibitory activities against Aβ42 aggregation, by sodium dodecyl sulfate (SDS)-PAGE and thioflavine T binding assay. Commercially available Arg-Arg-7-amino-4-trifluoromethylcoumarin was found to exhibit remarkable inhibitory activities to the formation of the globulomer and the fibril of Aβ42. This chimera-type tri-peptide is expected to serve as the seed molecule of a potent inhibitor of the Aβ aggregation process.
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  • Hailan LI, Young Sil MIN, Kyoung-Chan PARK, Dong-Seok KIM
    2012 Volume 76 Issue 4 Pages 767-771
    Published: April 23, 2012
    Released on J-STAGE: April 23, 2012
    Advance online publication: April 07, 2012
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    Xanthium strumarium L. (Asteraceae) is traditionally used in Korea to treat skin diseases. In this study, we investigated the effects of a X. strumarium stem extract on melanin synthesis. It inhibited melanin synthesis in a concentration-dependent manner, but it did not directly inhibit tyrosinase, the rate-limiting melanogenic enzyme, and instead downregulated microphthalmia-associated transcription factor (MITF) and tyrosinase expression. MITF, the master regulator of pigmentation, is a target of the Wnt signaling pathway, which includes glycogen synthase kinase 3β (GSK3β) and β-catenin. Hence, the influence of X. strumarium stem extract on GSK3β and β-catenin was further investigated. X. strumarium induced GSK3β phosphorylation (inactivation), but the level of β-catenin did not change. Moreover, a specific GSK3β inhibitor restored X. strumarium-induced melanin reduction. Hence, we suggest that X. strumarium inhibits melanin synthesis through downregulation of tyrosinase via GSK3β phosphorylation.
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  • Naoyuki UMEMOTO, Takayuki OHNUMA, Henri URPILAINEN, Takanori YAMAMOTO, ...
    2012 Volume 76 Issue 4 Pages 778-784
    Published: April 23, 2012
    Released on J-STAGE: April 23, 2012
    Advance online publication: April 07, 2012
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    Supplementary material
    Tryptophan residues located in the substrate-binding cleft of a class V chitinase from Nicotiana tabacum (NtChiV) were mutated to alanine and phenylalanine (W190F, W326F, W190F/W326F, W190A, W326A, and W190A/W326A), and the mutant enzymes were characterized to define the role of the tryptophans. The mutations of Trp326 lowered thermal stability by 5–7 °C, while the mutations of Trp190 lowered stability only by 2–4 °C. The Trp326 mutations strongly impaired enzymatic activity, while the effects of the Trp190 mutations were moderate. The experimental data were rationalized based on the crystal structure of NtChiV in a complex with (GlcNAc)4, in which Trp190 is exposed to the solvent and involved in face-to-face stacking interaction with the +2 sugar, while Trp326 is buried inside but interacts with the −2 sugar through hydrophobicity. HPLC analysis of anomers of the enzymatic products suggested that Trp190 specifically recognizes the β-anomer of the +2 sugar. The strong effects of the Trp326 mutations on activity and stability suggest multiple roles of the residue in stabilizing the protein structure, in sugar residue binding at subsite −2, and probably in maintaining catalytic efficiency by providing a hydrophobic environment for proton donor Glu115.
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  • Miho TAKEMURA, Tatsuro HAMADA, Haruka KIDA, Kanji OHYAMA
    2012 Volume 76 Issue 4 Pages 785-790
    Published: April 23, 2012
    Released on J-STAGE: April 23, 2012
    Advance online publication: April 07, 2012
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    The liverwort Marchantia polymorpha L. synthesizes various long-chain polyunsaturated fatty acids including arachidonic acid and eicosapentaenoic acid, neither of which is produced by higher plants. Here we report the effects of temperature on long-chain polyunsaturated fatty acid accumulation in the liverwort. The accumulation of ω-3 polyunsaturated fatty acids increased significantly as the growth temperature decreased. Specifically, the relative content of eicosapentaenoic acid to total fatty acids at 5 °C was approximately 3-fold higher than at 25 °C. On the other hand, the accumulation of ω-6 polyunsaturated fatty acids decreased at low temperatures. An analysis of gene expression indicated that the mRNA of the MpFAD3 gene for ER ω-3 desaturase increased significantly at 5 °C. These results indicate that in the liverwort the n-3 pathway was enhanced at low temperature, mainly via expression of the cold-induced ω-3 desaturase gene, leading to increased accumulation of eicosapentaenoic acid.
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  • Danar PRASEPTIANGGA, Makoto HIRAYAMA, Kanji HORI
    2012 Volume 76 Issue 4 Pages 805-811
    Published: April 23, 2012
    Released on J-STAGE: April 23, 2012
    Advance online publication: April 07, 2012
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    A novel lectin (CBA) was isolated from the green alga, Codium barbatum, by conventional chromatographic methods. The hemagglutination-inhibition profile with sugars and glycoproteins indicated that CBA had preferential affinity for complex type N-glycans but not for monosaccharides, unlike the other known Codium lectins specific for N-acetylgalactosamine. CBA consisted of an SS-linked homodimer of a 9257-Da polypeptide containing seven cysteine residues, all of which were involved in disulfide linkages. The cDNA of the CBA subunit coded a polypeptide (105 amino acids) including the signal peptide of 17 residues. The calculated molecular mass from the deduced sequence was 9705 Da, implying that the four C-terminal amino acids of the CBA proprotein subunit were post-translationally truncated to afford the mature subunit (84 amino acids). No significantly similar sequences were found during an in silico search, indicating CBA to be a novel protein. CBA is the first Codium lectin whose primary structure has been elucidated.
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  • Ken HAMURA, Wataru SABURI, Shotaro ABE, Naoki MORIMOTO, Hidenori TAGUC ...
    2012 Volume 76 Issue 4 Pages 812-818
    Published: April 23, 2012
    Released on J-STAGE: April 23, 2012
    Advance online publication: April 07, 2012
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    Cellobiose phosphorylase (CBP) catalyzes the reversible phosphorolysis of cellobiose to produce α-D-glucopyranosyl phosphate (Glc1P) and D-glucose. It is an essential enzyme for the metabolism of cello-oligosaccharides in a ruminal bacterium, Ruminococcus albus. In this study, recombinant R. albus CBP (RaCBP) produced in Escherichia coli was characterized. It showed highest activity at pH 6.2 at 50 °C, and was stable in a pH range of 5.5–8.8 and at below 40 °C. It phosphorolyzed only cellobiose efficiently, and the reaction proceeded through a random-ordered bi bi mechanism, by which inorganic phosphate and cellobiose bind in random order and D-glucose is released before Glc1P. In the synthetic reaction, RaCBP showed highest activity to D-glucose, followed by 6-deoxy-D-glucose. D-Mannose, 2-deoxy-D-glucose, D-glucosamine, D-xylose, 1,5-anhydro-D-glucitol, and gentiobiose also served as acceptors, although the activities for them were much lower than for D-glucose. D-Glucose acted as a competitive-uncompetitive inhibitor of the reverse synthetic reaction, which bound not only the Glc1P site (competitive) but also the ternary enzyme-Glc1P-D-glucose complex (uncompetitive).
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  • Takashi OCHIAI, Tomoya SUGITA, Ryuji KATO, Mina OKOCHI, Hiroyuki HONDA
    2012 Volume 76 Issue 4 Pages 819-824
    Published: April 23, 2012
    Released on J-STAGE: April 23, 2012
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    Peptide arrays in which peptides were immobilized on cellulose membranes through photolinkers were synthesized. The peptides were subsequently detached from the arrays by ultraviolet (UV) photolysis for 3 h, and were used to search for functional peptides that inhibit the activity of α-amylase derived from human pancreatic juice. Amino acid replacement with high-molecular-size amino acids, Arg (R), Phe (F), Trp (W), or Tyr (Y), for the first and seventh residues of amylase inhibitor peptide, GHWYYRCW, as previous reported, led to enhancement of the inhibitory effect of the peptide on α-amylase. In particular, one of the resulting peptides, RHWYYRYW, showed a stronger inhibitory effect than acarbose (which is used as a hypoglycemic agent) or inhibitor peptide GHWYYRCW.
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Biochemistry & Molecular Biology Notes
Food & Nutrition Science Regular Papers
  • Chao-Hsin LEE, Chih-Yi KUO, Chau-Jong WANG, Chi-Ping WANG, Yi-Ru LEE, ...
    2012 Volume 76 Issue 4 Pages 646-651
    Published: April 23, 2012
    Released on J-STAGE: April 23, 2012
    Advance online publication: April 07, 2012
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    Oxidative stress is the major contributor to acetaminophen (AAP)-caused liver damage. It promotes mitochondrial oxidative stress and collapses the mitochondrial membrane potential to cause cell death. We have previously shown that a polyphenol extract of Hibiscus sabdariffa L. (HPE) potentiated the antioxidative effect. We further examined in this study the possible mechanism of HPE against AAP-caused liver damage. BABL/c mice were orally fed with HPE (100, 200 or 300 mg/kg) for two weeks prior to an i.p. injection of 1000 mg/kg of AAP. The mice were decapitated 6 h after the AAP injection to collect the blood and liver for further determination. The results show that pretreating with HPE increased the level of glutathione (GSH), decreased the level of lipid peroxidation, and increased catalase activity in the liver. A histopathological evaluation shows that HPE could decrease AAP-induced liver sterosis accompanied by a decreased expression of AIF, Bax, Bid, and p-JNK in the liver. An in vitro assay revealed that HPE could reduce AAP-induced death of BABL/c normal liver cells (BNLs), reverse the lost mitochondrial potency and improve the antioxidative status, similarly to the results of the in vivo assay. We show in this study that HPE possessed the ability to protect the liver from AAP-caused injury. The protective mechanism might be regulated by decreasing oxidative stress and attenuating the mitochondrial dysfunction.
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  • Masaki KATO, Yusuke ITO, Yasutake TANAKA, Masao SATO, Katsumi IMAIZUMI ...
    2012 Volume 76 Issue 4 Pages 660-664
    Published: April 23, 2012
    Released on J-STAGE: April 23, 2012
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    We had previously found plant sterols deposited in the bodies of stroke-prone spontaneously hypertensive rats (SHRSP)/Sea and Wistar Kyoto (WKY)/NCrlCrlj rats that had a missense mutation in the Abcg5 cDNA sequence that coded for ATP-binding cassette transporter (ABC) G5. We used SHRSP/Izm, WKY/NCrlCrlj, and WKY/Izm rats in the present study to determine the mechanisms for plant sterol deposition in the body. Jcl:Wistar rats were used as a control strain. A diet containing 0.5% plant sterols fed to the rats resulted in plant sterol deposition in the body of SHRSP/Izm, but not in WKY/Izm or Jcl:Wistar rats. Only a single non-synonymous nucleotide change, G1747T, resulting in a conservative cysteine substitution for glycine at amino acid 583 (Gly583Cys) in Abcg5 cDNA was identified in the SHRSP/Izm and WKY/NCrlCrlj rats. However, this mutation was not found in the WKY/Izm or Jcl:Wistar rats. No significant difference in the biliary secretion or lymphatic absorption of plant sterols was apparent between the rat strains with or without the missense mutation in Abcg5 cDNA. Our observations suggest that plant sterol deposition in rat strains with the missense mutation in Abcg5 cDNA can occur, despite there being no significant change in the biliary secretion or lymphatic absorption of plant sterols.
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  • Noriyuki KOHDA, Shoichiro INOUE, Tsuneyuki NODA, Takao SAITO
    2012 Volume 76 Issue 4 Pages 732-736
    Published: April 23, 2012
    Released on J-STAGE: April 23, 2012
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    We evaluated the effects of chitosan intake on fecal excretion of bisphenol A (BPA) and di(2-ethyl)phthalate (DEHP) in rats. The rats were fed a chitosan diet (CHI group) or a control diet (control group) for 10 d and orally administrated BPA or DEHP (100, 500 mg/kg body weight, respectively) on day 4. Feces were collected and the rates of fecal excretion of BPA and DEHP were calculated. Fecal excretion rates of BPA and DEHP were significantly higher in the CHI group than in the control group. A significant negative correlation was observed between the fecal excretion rates of BPA and DEHP and apparent fat digestibility. Furthermore, the CHI group showed not only increased but also accelerated BPA excretion into the feces. In conclusion, we found that that chitosan intake significantly increased the fecal excretion of BPA, DEHP, and fat, suggesting that it might be useful for reducing adverse effects caused by lipophilic xenobiotics.
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  • Yuri KIM, Jina KIM, Seung-Min LEE, Hyun Ah LEE, Seolhyun PARK, Yesl KI ...
    2012 Volume 76 Issue 4 Pages 737-744
    Published: April 23, 2012
    Released on J-STAGE: April 23, 2012
    Advance online publication: April 07, 2012
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    The growing incidence of prostate cancer and the traditional use of Rubus coreanus Miquel (RCM) for prostate health led us to compare RCM extracts and to test their efficacy in inhibiting the growth of prostate cancer cells differing in androgen dependency. Ethanol extracts of unripe RCM (EUR) were more effective in reducing cell viability than water extracts or ripe RCM. EUR-induced growth inhibition, as indicated by significant reductions in numbers of proliferating cells and decreases in the protein levels of proliferating cell nuclear antigen (PCNA), cyclin D1 and CDK4, was greater in the androgen-dependent LNCaP cells than in the androgen-independent DU145 cells. EUR also induced mitochondrial-mediated apoptosis in prostate cancer cells by reducing Bcl-2 and Bcl-XL levels, but increased Bax levels. Nevertheless, the LNCaP cells were more sensitive to EUR-induced apoptosis and displayed sub-G1 and late apoptotic cell populations, whereas the DU145 cells did not. Our findings suggest that EUR suppresses the growth of prostate cancer cells by anti-proliferative and/or pro-apoptotic effects, and that these effects are stronger in androgen-dependent cells.
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  • Seong-Il KANG, Hye-Sun SHIN, Hyo-Min KIM, Youn-Suk HONG, Seon-A YOON, ...
    2012 Volume 76 Issue 4 Pages 755-761
    Published: April 23, 2012
    Released on J-STAGE: April 23, 2012
    Advance online publication: April 07, 2012
    JOURNAL FREE ACCESS
    This study explores the anti-obesity properties of a Sasa quelpaertensis leaf extract (SQE) in high-fat diet (HFD)-induced obese C57BL/6 mice and mature 3T3-L1 adipocytes. SQE administration with HFD for 70 d significantly decreased the body weight gain, adipose tissue weight, and serum total cholesterol and triglyceride levels in comparison with the HFD group. SQE administration also reduced the serum levels of glutamic oxaloacetic transaminase, glutamic pyruvic transaminase and lactate dehydrogenase, and the accumulation of lipid droplets in the liver, suggesting a protective effect against HFD-induced hepatic steatosis. SQE administration restored the HFD-induced decreases with phosphorylation of AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC) in epididymal adipose tissue. SQE also induced AMPK phosphorylation in mature 3T3-L1 adipocytes. These results suggest that SQE exerted an anti-obesity effect on HFD-induced obese mice by activating AMPK in adipose tissue and reducing lipid droplet accumulation in the liver.
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  • Sumiko NAKAMURA, Dai SUZUKI, Ryota KITADUME, Ken’ichi OHTSUBO
    2012 Volume 76 Issue 4 Pages 794-804
    Published: April 23, 2012
    Released on J-STAGE: April 23, 2012
    Advance online publication: April 07, 2012
    JOURNAL FREE ACCESS
    The processing suitability as a material for rice crackers was characterized in the present study, based on physicochemical measurements and sensory testing of high-quality premium rice, low-amylose rice, Japonica-Indica hybrid rice, and red rice as the rice cultivar samples. Puffed rice crackers were prepared and the relationship between the physicochemical properties of the rice grains and the quality of the resulting products was investigated. It was possible to estimate the physical properties of a rice cracker by using multiple-regression analysis based on the chemical components, pasting properties and physical properties of the constituent rice. A formula for estimating the amylose content of the constituent rice was developed from the results of physicochemical measurements of the rice crackers. We assayed the quality of commercial rice crackers and examined the deterioration during the storage by measuring the physicochemical properties. The hardness and fat acidity of crackers increased markedly during storage for 20 d at 35 °C. The novel method of a one-bite test with a Tensipresser was useful to assay the quality of a rice cracker and made it possible to evaluate the quality deterioration of the rice cracker during storage.
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Food & Nutrition Science Notes
Microbiology & Fermentation Technology Regular Papers
  • Takahiro ABE, Fatma Pinar SAHIN, Kiyotaka AKIYAMA, Takayuki NAITO, Miz ...
    2012 Volume 76 Issue 4 Pages 633-639
    Published: April 23, 2012
    Released on J-STAGE: April 23, 2012
    Advance online publication: April 07, 2012
    JOURNAL FREE ACCESS
    Symbionts of the marine sponge Halichondria okadai are promising as a source of natural products. Metagenomic technology is a powerful tool for accessing the genetic and biochemical potential of bacteria. Hence, we established a method of recovering bacterial-enriched metagenomic DNA by stepwise centrifugation. The metagenomic DNA was analyzed by ultrafast 454-pyrosequencing technology, and the results suggested that more than three types of bacterial DNA, Alphaproteobacteria, Actinobacteria, and Cyanobacteria, had been recovered, and that eukaryotic genes comprised only 0.02% of the metagenomic DNA. These results indicate that stepwise centrifugation and real-time quantitative PCR were effective for separating sponge cells and symbiotic bacteria, and that we constructed a bacteria-enriched metagenomic library from a marine sponge, H. okadai, selectively for the first time.
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  • Mai NAKASE, Yuta TSUKAMOTO, Akira HOSOMI, Tomo MATSUDA, Masaaki MIYAMO ...
    2012 Volume 76 Issue 4 Pages 652-659
    Published: April 23, 2012
    Released on J-STAGE: April 23, 2012
    Advance online publication: April 07, 2012
    JOURNAL FREE ACCESS
    The functions of two Schizosaccharomyces pombe Vps9-like genes, SPBC4F6.10/vps901+ and SPBC29A10.11c/vps902+, were characterized. Genomic sequence analysis predicted that Vps901p contains a VPS9 domain, whereas cDNA analyses revealed that Vps901p contains a CUE domain (coupling of ubiquitin to ER degradation) in its C-terminal region. Deletion of vps901+ resulted in mis-sorting and secretion of S. pombe vacuolar carboxypeptidase Cpy1p, whereas deletion of vps902+ had no effect, suggesting that only Vps901p functions in vacuolar protein transport in S. pombe. Deletion of vps901+ further produced pleiotropic phenotypes, including vacuolar homotypic fusion and endocytosis defects. Heterologous expression of the budding yeast VPS9 gene corrected the CPY mis-sorting defect in vps901Δ cells. These findings suggest that the VPS9 domain of Vps901p is required for vacuolar protein trafficking in S. pombe.
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  • Pongsak RATTANACHAIKUNSOPON, Parichat PHUMKHACHORN
    2012 Volume 76 Issue 4 Pages 665-670
    Published: April 23, 2012
    Released on J-STAGE: April 23, 2012
    Advance online publication: April 07, 2012
    JOURNAL FREE ACCESS
    Aeromonas salmonicida is one of the major fish pathogens causing economically devastating losses in aquaculture. A. salmonicida subsp. salmonicida is a typical A. salmonicida causing furunculosis, while the other subspecies are atypical strains causing ulcer diseases. PCR-based methods of detecting A. salmonicida suffer from the drawback that they do not distinguish living (pathogenic) from dead cells. In this study, a method of detecting A. salmonicida was developed based on reverse transcription-multiplex PCR (RT-MPCR) using two sets of primers, SV1/SV2 and SF1/SF2, specific to the vapA gene and the fstB gene of A. salmonicida respectively. This method was found to detect A. salmonicida specifically with detection limits of 10 CFU in pure culture and 30 CFU in the presence of tissue debris. It was also found distinguish not only between viable and nonviable cells but also between typical and atypical strains of A. salmonicida. Using RT-MPCR, two DNA fragments, of 542 and 1,258 bp, were amplified from RNA of typical A. salmonicida, whereas only one DNA fragment, of 542 bp, was amplified from the RNA of the atypical ones. The proposed assay was also used successfully to detect A. salmonicida in artificially infected rainbow trout (Oncorhyncus mykiss).
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  • Mingjun ZHU, Ping LI, Xinfang GONG, Jufang WANG
    2012 Volume 76 Issue 4 Pages 671-678
    Published: April 23, 2012
    Released on J-STAGE: April 23, 2012
    Advance online publication: April 07, 2012
    JOURNAL FREE ACCESS
    The processes of separate hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF) were employed using Saccharomyces cerevisiae for the production of ethanol from cassava pulp without any pretreatment. A combination of amylase, cellulase, cellobiase, and glucoamylase produced the highest levels of ethanol production in both the SHF and the SSF method. A temperature of 37 °C, a pH of 5.0, and an inoculum size of 6% were the optimum conditions for SSF. For the batch process at a pulp concentration of 20%, ethanol production levels from SHF and SSF were the highest, at 23.51 and 34.67 g L−1 respectively, but in the fed-batch process, the levels of ethanol production from SHF and SSF rose to 29.39 and 43.25 g L−1 respectively, which were 25% and 24.7% higher than those of the batch process. Thus SSF using the fed-batch provided a more efficient method for the utilization of cassava pulp.
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Microbiology & Fermentation Technology Notes
Environmental Science Communication
  • Ken SASAKI, Hiroyo MORIKAWA, Takashi KISHIBE, Ayaka MIKAMI, Toshihiko ...
    2012 Volume 76 Issue 4 Pages 859-862
    Published: April 23, 2012
    Released on J-STAGE: April 23, 2012
    Advance online publication: April 07, 2012
    JOURNAL FREE ACCESS
    About 90% of the radioactive Cs in the sediment mud of a school’s swimming pool in Fukushima, Japan was removed by treatment for 3 d using the alginate immobilized photosynthetic bacterium Rhodobcater sphaeroides SSI. Even though batch treatment was carried out 3 times repeatedly, the activity of immobilized cells in removing Cs was maintained at levels of about 84% (second batch) and 78% (third batch). Cs was strongly attached to the sediment mud because, even with HNO3 treatment at pH of 2.00–1.60 for 24 h, it was not eluted into the water. Furthermore, more than 75% of the Cs could be removed without solubilization with HNO3. This suggests that the Cs attached to the sediment mud was transformed into immobilized cells via the Cs+ ion by the negative charge of the immobilized cell surface and/or the potassium transport system of the photosynthetic bacterium.
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