Bioscience, Biotechnology, and Biochemistry
Online ISSN : 1347-6947
Print ISSN : 0916-8451
Volume 76 , Issue 6
Showing 1-36 articles out of 36 articles from the selected issue
Award Review
  • Takuya TASHIRO
    2012 Volume 76 Issue 6 Pages 1055-1067
    Published: June 23, 2012
    Released: June 23, 2012
    [Advance publication] Released: June 07, 2012
    JOURNALS FREE ACCESS
    KRN7000, an anticancer drug candidate developed by Kirin Brewery Co. in 1995, is an α-galactosyl ceramide. It is a ligand making a complex with CD1d protein, and it stimulates invariant natural killer T (NKT) cells, which are one of the lineages of immunocytes. NKT cells activated by recognition of the CD1d/KRN7000 complex with its invariant T-cell receptor (TCR) can induce both protective and regulatory immune responses. To determine the recognition and activation mechanisms of NKT cells and to develop drug candidates more effective than KRN7000, a large number of analogs of KRN7000 have been synthesized. Some of them show potent bioactivities and have the potential of being utilized as therapeutic agents. In this review, structure-activity relationship studies of novel glycolipids which stimulate NKT cells efficiently are summarized.
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Organic Chemistry Regular Papers
  • Ji Young CHO, Ji Young KANG, Yong Ki HONG, Hyo Hyun BAEK, Hyoun Woong ...
    2012 Volume 76 Issue 6 Pages 1116-1121
    Published: June 23, 2012
    Released: June 23, 2012
    [Advance publication] Released: June 07, 2012
    JOURNALS FREE ACCESS
    Marine derived actinomycetes constituting 185 strains were screened for their antifouling activity against the marine seaweed, Ulva pertusa, and fouling diatom, Navicula annexa. Strain 291-11 isolated from the seaweed, Undaria pinnatifida, rhizosphere showed the highest antifouling activity and was identified as Streptomyces praecox based on a 16S rDNA sequence analysis. Strain 291-11 was therefore named S. praecox 291-11. The antifouling compounds from S. praecox 291-11 were isolated, and their structures were analyzed. The chemical constituents representing the antifouling activity were identified as (6S,3S)-6-benzyl-3-methyl-2,5-diketopiperazine (bmDKP) and (6S,3S)-6-isobutyl-3-methyl-2,5-diketopiperazine (imDKP) by interpreting the nuclear magnetic resonance and high-resolution mass spectroscopy data. Approximately 4.8 mg of bmDKP and 3.1 mg of imDKP were isolated from 1.2 g of the S. praecox 291-11 crude extract. Eight different compositions of culture media were investigated for culture, the TBFeC medium being best for bmDKP and TCGC being the optimum for imDKP production. Two compounds respectively showed a 17.7 and 21 therapeutic ratio (LC50/EC50) to inhibit zoospores, and two compounds respectively showed a 263 and 120.2 therapeutic ratio to inhibit diatoms.
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  • Masayuki KAGEYAMA, Takuho MIYAGI, Mayumi YOSHIDA, Tomohiro NAGASAWA, H ...
    2012 Volume 76 Issue 6 Pages 1219-1225
    Published: June 23, 2012
    Released: June 23, 2012
    [Advance publication] Released: June 07, 2012
    JOURNALS FREE ACCESS
    EFdA (4'-ethynyl-2-fluoro-2'-deoxyadenosine), a nucleoside reverse transcriptase inhibitor with extremely potent anti-HIV activity, was concisely synthesized from (R)-glyceraldehyde acetonide in an 18% overall yield by a 12-step sequence involving highly diastereoselective ethynylation of an α-alkoxy ketone intermediate. The present synthesis is superior, both in overall yield and in the number of steps, to the previous one which required 18 steps from an expensive starting material and resulted in a modest overall yield of 2.5%.
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Organic Chemistry Note
Biochemistry & Molecular Biology Regular Papers
  • Nhung Hong NGUYEN, Lalita MARUSET, Tanaporn UENGWETWANIT, Wuttichai MH ...
    2012 Volume 76 Issue 6 Pages 1075-1084
    Published: June 23, 2012
    Released: June 23, 2012
    [Advance publication] Released: June 07, 2012
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    Microorganisms residing in the rumens of cattle represent a rich source of lignocellulose-degrading enzymes, since their diet consists of plant-based materials that are high in cellulose and hemicellulose. In this study, a metagenomic library was constructed from buffalo rumen contents using pCC1FOS fosmid vector. Ninety-three clones from the pooled library of approximately 10,000 clones showed degrading activity against AZCL-HE-Cellulose, whereas four other clones showed activity against AZCL-Xylan. Contig analysis of pyrosequencing data derived from the selected strongly positive clones revealed 15 ORFs that were closely related to lignocellulose–degrading enzymes belonging to several glycosyl hydrolase families. Glycosyl hydrolase family 5 (GHF5) was the most abundant glycosyl hydrolase found, and a majority of the GHF5s in our metagenomes were closely related to several ruminal bacteria, especially ones from other buffalo rumen metagenomes. Characterization of BT-01, a selected clone with highest cellulase activity from the primary plate screening assay, revealed a cellulase encoding gene with optimal working conditions at pH 5.5 at 50 °C. Along with its stability over acidic pH, the capability efficiently to hydrolyze cellulose in feed for broiler chickens, as exhibited in an in vitro digestibility test, suggests that BT-01 has potential application as a feed supplement.
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  • Yue-Xiu SI, Zhi-Jiang WANG, Daeui PARK, Hyoung Oh JEONG, Sen YE, Hae Y ...
    2012 Volume 76 Issue 6 Pages 1091-1097
    Published: June 23, 2012
    Released: June 23, 2012
    [Advance publication] Released: June 07, 2012
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    We studied the inhibitory effects of isorhamnetin on mushroom tyrosinase by inhibition kinetics and computational simulation. Isorhamnetin reversibly inhibited tyrosinase in a mixed-type manner at Ki=0.235 ± 0.013 mM. Measurements of intrinsic and 1-anilinonaphthalene-8-sulfonate(ANS)-binding fluorescence showed that isorhamnetin did not induce significant changes in the tertiary structure of tyrosinase. To gain insight into the inactivation process, the kinetics were computed via time-interval measurements and continuous substrate reactions. The results indicated that inactivation induced by isorhamnetin was a first-order reaction with biphasic processes. To gain further insight, we simulated docking between tyrosinase and isorhamnetin. Simulation was successful (binding energies for Dock6.3: −32.58 kcal/mol, for AutoDock4.2: −5.66 kcal/mol, and for Fred2.2: −48.86 kcal/mol), suggesting that isorhamnetin interacts with several residues, such as HIS244 and MET280. This strategy of predicting tyrosinase interaction in combination with kinetics based on a flavanone compound might prove useful in screening for potential natural tyrosinase inhibitors.
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  • Kazuma MURAKAMI, Nakaba MURATA, Yoshihiro NODA, Kazuhiro IRIE, Takuji ...
    2012 Volume 76 Issue 6 Pages 1098-1103
    Published: June 23, 2012
    Released: June 23, 2012
    [Advance publication] Released: June 07, 2012
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    Oxidative stress is involved in the pathogenesis of neurodegeneration. Amyloid β (Aβ) oligomer as an intermediate of aggregates causes memory loss in Alzheimer's disease (AD). We have suggested that oxidative stress plays an important role in Aβ oligomerization and cognitive impairment using a human amyloid precursor protein (hAPP) transgenic AD mice lacking cytoplasmic superoxide dismutase (hAPP/Sod1−/−). Recently, clinical trials revealed inhibitors of Aβ production from hAPP as promising therapeutics, but the relationship between oxidative stress and Aβ metabolism remains unclear. Here we found that Sod1 deficiency enhanced β-cleavage of hAPP, suggesting that it increased Aβ production in hAPP/Sod1−/− mice. In contrast, Aβ degradation did not decrease in hAPP/Sod1−/− as compared with hAPP/Sod1+/+ mice. Furthermore, we successfully detected in situ superoxide radicals associated with increased protein carbonylation in hAPP/Sod1−/−. These results suggest that cytoplasmic oxidative stress is involved in Aβ production as well as aggregation during AD progression.
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  • Yen-Hua HUANG, Hsin-Hsien LIN, Cheng-Yang HUANG
    2012 Volume 76 Issue 6 Pages 1110-1115
    Published: June 23, 2012
    Released: June 23, 2012
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    PriB is a primosomal protein required for re-initiation of replication in bacteria. We characterized and compared the DNA-binding properties of PriB from Salmonella enterica serovar Typhimurium LT2 (StPriB) and Escherichia coli (EcPriB). Only one residue of EcPriB, V6, was different in StPriB (replaced by A6). Previous structural information revealed that this residue is located on the putative dimer-dimer interface of PriB and is not involved in single-stranded DNA (ssDNA) binding. The cooperative binding mechanism of StPriB to DNA is, however, very different from that of EcPriB. Unlike EcPriB, which forms a single complex with ssDNAs of various lengths, StPriB forms two or more distinct complexes. Based on these results, as well as information on structure, binding modes for forming a stable complex of PriB with ssDNA of 25 nucleotides (nt), (EcPriB)25, and (StPriB)25 are proposed.
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  • Yong-Jae KIM, Yusu SHIN, Kwang Ho LEE, Tack-Joong KIM
    2012 Volume 76 Issue 6 Pages 1122-1127
    Published: June 23, 2012
    Released: June 23, 2012
    [Advance publication] Released: June 07, 2012
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    Inflammation is a system used by a host to defend against the presence of bacteria, viruses, or yeasts. Toll-like receptors (TLRs) in the plasma membranes of macrophages are activated when they recognize the molecular structure of a virus or bacterium. Lipopolysaccharide (LPS), an outer cell-wall component of Gram-negative bacteria, initiates an inflammatory process via TLR4. We investigated the effect of the extract of Anethum graveloens flowers (AGFs) on LPS-mediated inflammation in RAW 264.7 cells. The extract markedly suppressed nitric oxide generation in a concentration-dependent manner in LPS-stimulated RAW 264.7 cells. It inhibited inducible nitric oxide synthase (iNOS) and the mRNA expression of cytokines such as interleukin-1 beta and interleukin-6 in LPS-stimulated RAW 264.7 cells. It also inhibited iNOS protein levels in LPS-stimulated RAW 264.7 cells. In addition, AGF decreased the LPS-induced phosphorylation of mitogen-activated protein kinases in LPS-stimulated RAW 264.7 cells. AGF inhibited the phosphorylation of Akt, an upstream molecule of the nuclear factor kappa B (NF-κB) pathway, and thus inhibited NF-κB activity in LPS-stimulated RAW 264.7 cells. These results suggest that AGF exerts an anti-inflammatory effect in LPS-stimulated RAW 264.7 cells by inhibiting iNOS expression and blocking the NF-κB pathway.
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  • Panhui WANG, Takaaki KOJIMA, Tetsuo KOBAYASHI, Hideo NAKANO
    2012 Volume 76 Issue 6 Pages 1128-1134
    Published: June 23, 2012
    Released: June 23, 2012
    [Advance publication] Released: June 07, 2012
    JOURNALS FREE ACCESS
    Supplementary material
    The in vitro DNA binding profile of Aspergillus nidulans transcription factor AmyR was analyzed by a novel approach employing a genetic library of beads and flow cytometry analysis. An artificial library with 22 randomized nucleotides was constructed and subjected to a protein-DNA binding reaction with MalE-tagged AmyR. DNA fragments with potential AmyR-binding sites were labeled with fluorescence-conjugated antibody to be enriched by flow cytometry through 5 rounds of successive selection. Finally, a binding motif with a single CGG triplet was obtained from DNA fragments showing weak AmyR binding, while another motif with dual CGG triplets was discovered with stronger binding fragments. An informative motif, CGGNNNTTTNTCGG, was found to exist only in the promoter region of highly AmyR-dependent genes. These results suggest that this system is a powerful tool for the rapid and comprehensive analysis of the binding preferences of transcription factors.
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  • Suyeon KIM, Yeon-Ok KIM, Yongjik LEE, Inseong CHOI, Chandrashekhar P. ...
    2012 Volume 76 Issue 6 Pages 1140-1145
    Published: June 23, 2012
    Released: June 23, 2012
    [Advance publication] Released: June 07, 2012
    JOURNALS FREE ACCESS
    Supplementary material
    Plants are attractive expression systems for large-scale, low-cost production of high-value proteins. The xylanase 2 gene (Xyn2), encoding an endo-β-1,4-xylanase from Trichoderma reesei, was cloned and expressed in Escherichia coli and the poplar (Populus spp.). The optimal temperature and pH of the recombinant xylanase were 50 °C and 5.0 respectively when expressed in E. coli. The purpose of this study was to produce recombinant xylanase in poplar. The Xyn2 gene was transferred into poplars by Agrobacterium-mediated transformation. The transgenic status and transgene expression of the transformed poplar were confirmed by polymerase chain reaction (PCR) genotyping and reverse transcription (RT)-PCR analysis. The poplar-expressed xylanase was biologically active, with an expression level of up to 14.4% of total leaf soluble protein. In the leaves, the average xylanase content was 1.016 mg per g of leaf fresh weight in the transgenic poplar. We found that the poplar might make possible the large-scale production of commercially important recombinant proteins.
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  • Kentaro TSUJI-NAITO, Ralph W. JACK
    2012 Volume 76 Issue 6 Pages 1150-1154
    Published: June 23, 2012
    Released: June 23, 2012
    [Advance publication] Released: June 07, 2012
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    Supplementary material
    Concentrated fractions of low molecular weight whey proteins (1–30 kDa), that is concentrated bovine milk whey active proteins (CBP), have been found to enhance bone formation in both in vivo and clinical studies, but the underlying mechanisms are poorly understood. In this study, we found that CBP promoted osteoblastic differentiation in normal human osteoblasts, and determined the involvement of the c-jun NH2-terminal kinase (JNK)-activating transcription factor 4 (ATF4) pathway. We observed that alkaline phosphatase activity and mineralization were significantly induced by CBP treatment. In addition, mRNA expression of ATF4 was intensely elevated in CBP-treated osteoblasts, indicating that the late-phase events of differentiation were promoted. We found that CBP activated the phosphorylation of JNK and extracellular signal-regulated kinase (ERK). Furthermore, pathway analyses using the various signaling pathway-specific inhibitors revealed that JNK activation, but not ERK activation, is essential for CBP-induced mineralization and ATF4 expression. Our results indicate that the JNK-mediated ATF4 pathway is required for CBP-promotive osteogenesis.
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  • Shingo SAKAMOTO, Yukichi FUJIKAWA, Nobukazu TANAKA, Muneharu ESAKA
    2012 Volume 76 Issue 6 Pages 1155-1162
    Published: June 23, 2012
    Released: June 23, 2012
    [Advance publication] Released: June 07, 2012
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    L-Galactose-1-phosphate phosphatase (GPPase) is an enzyme involved in ascorbate biosynthesis in higher plants. We isolated a cDNA encoding GPPase from tobacco, and named it NtGPPase. The putative amino acid sequence of NtGPPase contained inositol monophosphatase motifs and metal binding sites. Recombinant NtGPPase hydrolyzed not only L-galactose-1-phosphate, but also myo-inositol-1-phosphate. The optimum pH for the GPPase activity of NtGPPase was 7.5. Its enzyme activity required Mg2+, and was inhibited by Li+ and Ca2+. Its fluorescence, fused with green fluorescence protein in onion cells and protoplasts of tobacco BY-2 cells, was observed in both the cytosol and nucleus. The expression of NtGPPase mRNA and protein was clearly correlated with L-ascorbic acid (AsA) contents of BY-2 cells during culture. The AsA contents of NtGPPase over expression lines were higher than those of empty lines at 13 d after subculture. This suggests that NtGPPase contributes slightly to AsA biosynthesis.
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  • Natale VITTORI, Mercedes MARTÍN, Bartolomé SABATER
    2012 Volume 76 Issue 6 Pages 1169-1172
    Published: June 23, 2012
    Released: June 23, 2012
    [Advance publication] Released: June 07, 2012
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    Acetylated polymannan polysaccharide (ApmP) isolated from Aloe barbadensis Miller contains a stable peroxidase that was solubilized to investigate its biochemical, electrophoretic, immunological, and proteomic properties. In the electrophoretic band corresponding to the solubilized peroxidase, proteomic analysis detected seven tryptic peptides that matched homologous peptides covering one third of the ATP22a peroxidase of Arabidopsis thaliana. All the characteristics tested indicated that the activity stabilized within the ApmP pertains to the basic secretory peroxidase family, which includes members that have several biotechnological uses. Hence ApmP might yield a widely used peroxidase in stabilized form.
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  • Masao YAMASAKI, Masahiro IWASE, Kazuo KAWANO, Yoichi SAKAKIBARA, Masah ...
    2012 Volume 76 Issue 6 Pages 1177-1181
    Published: June 23, 2012
    Released: June 23, 2012
    [Advance publication] Released: June 07, 2012
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    We determined the effects of apocynin, a representative inhibitor of NADPH oxidase, on the proliferative and adhesive properties of 3Y1 rat fibroblasts and the 3Y1 v-H-ras-transformed derivative, HR-3Y1-2. Apocynin inhibited the proliferation of HR-3Y1-2 but not 3Y1 cells at 10 µM and 100 µM. Apocynin also decreased the intracellular reactive oxygen species (ROS) level in HR-3Y1-2 but not 3Y1 cells. We also evaluated the effects of apocynin on cell adhesion to fibronectin and found decreased adhesion of HR-3Y1-2 cells to fibronectin-coated plates. Our results indicate that apocynin selectively down-regulated β1-integrin cell surface expression on the HR-3Y1-2 cells. It also inhibited the migration and invasion of these cells. These data suggest that reducing the production of NADPH oxidase-mediated ROS could be an effective means for ameliorating the abnormal growth, adhesion and motility of v-H-ras-transformed cells.
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  • Pongsak RATTANACHAIKUNSOPON, Parichat PHUMKHACHORN
    2012 Volume 76 Issue 6 Pages 1189-1194
    Published: June 23, 2012
    Released: June 23, 2012
    [Advance publication] Released: June 07, 2012
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    A novel method for the identification of viable Listeria species was developed based on reverse transcription-multiplex PCR (RT-MPCR) and restriction digestion. The targets for RT-MPCR were iap mRNAs whose genes are common to all Liseria species. A set of five primers was used in this study. Two of them were genus specific, and the other three were specific to L. monocytogenase, L. innocua, and L. grayi respectively. By RT-MPCR, L. monocytogenese, L. innocua, L. grayi, and a group of Listeria species, including L. ivanovii, L. welshimeri, and L. seeligeri, were specifically identified. To differentiate the latter three Listeria species, RT-MPCR products were subjected to digestion with HpaI and ScaI. The sensitivity of RT-MPCR in detecting Listeria species was determined to be 50 CFU/mL. RT-MPCR was found to discriminate between viable and nonviable cells and to detect viable Listeria species in a food model.
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  • Koko MORIYA, Takuo YAMAMOTO, Emi TAKAMITSU, Yukari MATSUNAGA, Mayumi K ...
    2012 Volume 76 Issue 6 Pages 1201-1209
    Published: June 23, 2012
    Released: June 23, 2012
    [Advance publication] Released: June 07, 2012
    JOURNALS FREE ACCESS
    Supplementary material
    The subcellular localization of 13 recently identified N-myristoylated proteins and the effects of overexpression of these proteins on cellular morphology were examined with the aim of understanding the physiological roles of the protein N-myristoylation that occurs on these proteins. Immunofluorescence staining of HEK293T cells transfected with cDNAs coding for the proteins revealed that most of them were associated with the plasma membrane or the membranes of intracellular compartments, and did not affect cellular morphology. However, two proteins, formin-like2 (FMNL2) and formin-like3 (FMNL3), both of them are members of the formin family of proteins, were associated mainly with the plasma membrane and induced significant cellular morphological changes. Inhibition of protein N-myristoylation by replacement of Gly2 with Ala or by the use of N-myristoylation inhibitor significantly inhibited membrane localization and the induction of cellular morphological changes, indicating that protein N-myristoylation plays critical roles in the cellular morphological changes induced by FMNL2 and FMNL3.
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  • Mingdong AN, Ping CAI, Ming YAN, Ning HAO, Shanshan WANG, Huan LIU, Ya ...
    2012 Volume 76 Issue 6 Pages 1210-1212
    Published: June 23, 2012
    Released: June 23, 2012
    [Advance publication] Released: June 07, 2012
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    A novel NADPH-dependent reductase (CaCR) from Candida albicans was cloned for the first time. It catalyzed asymmetric reduction to produce ethyl (S)-4-chloro-3-hydroxybutanoate ((S)-CHBE). It contained an open reading frame of 843 bp encoding 281 amino acids. When co-expressed with a glucose dehydrogenase in Escherichia coli, recombinant CaCR exhibited an activity of 5.7 U/mg with ethyl 4-chloro-3-oxobutanoate (COBE) as substrate. In the biocatalysis of COBE to (S)-CHBE, 1320 mM (S)-CHBE was obtained without extra NADP+/NADPH in a water/butyl acetate system, and the optical purity of the (S)-isomer was higher than 99% enantiomeric excess.
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Biochemistry & Molecular Biology Notes
Biochemistry & Molecular Biology Communications
Food & Nutrition Science Regular Papers
  • Jin-Nyoung HO, Mi-Eun SON, Won-Chul LIM, Seung-Taik LIM, Hong-Yon CHO
    2012 Volume 76 Issue 6 Pages 1068-1074
    Published: June 23, 2012
    Released: June 23, 2012
    [Advance publication] Released: June 07, 2012
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    Lipid accumulation using Oil Red O dye was measured in 3T3-L1 murine adipocytes to examine the anti-obesity effect of four types of germinated rice, including germinated brown rice (GBR), germinated waxy brown rice (GWBR), germinated black rice (GB-R), and germinated waxy black rice (GWB-R). GBR methanol extract exhibited the highest suppression of lipid accumulation in the 3T3-L1 cell line and also the anti-obesity effect of GBR on high fat induced-obese mice. The mice were divided into three groups and were administered: ND, a normal diet; HFD control, a high fat diet; and GBR, a high fat diet plus 0.15% GBR methanol extract for 7 weeks. GBR administration significantly decreased body weight gain and lipid accumulation in the liver and epididymal adipose tissue as compared to the HFD control group. In addition, serum triglycerides (TGs) and total cholesterol (TC) levels were significantly decreased by following GBR administration compared with those in the HFD control group, whereas the high-density lipoprotein (HDL) cholesterol level increased. Furthermore, the mRNA levels of adipogenic transcriptional factors, such as CCAAT enhancer binding protein (C/EBP)-α, sterol regulatory element-binding protein (SREBP)-1c, and peroxisome proliferator activated receptors (PPAR)-γ, and related genes (aP2, FAS), decreased significantly. Taken together, GBR administration suppressed body weight gain and lipid accumulation in the liver and epididymal adipocytes, and improved serum lipid profiles, in part, by controlling adipogenesis through a reduction in transcriptional factors. These results suggest that GBR is a potential agent against obesity.
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  • Wenya CHEN, Tohru HIRA, Shingo NAKAJIMA, Hiroshi TOMOZAWA, Masahito TS ...
    2012 Volume 76 Issue 6 Pages 1104-1109
    Published: June 23, 2012
    Released: June 23, 2012
    [Advance publication] Released: June 07, 2012
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    We have recently reported that oral gavage of a potato extract (Potein®) suppressed the food intake in rats. The satiating effect of the potato extract was compared in the present study to other protein sources, and the involvement of endogenous cholecystokinin (CCK) secretion was examined. Food consumption was measured in 18-h fasted rats after oral gavage of the potato extract or other protein sources. The CCK-releasing activity of the potato extract was then examined in anesthetized rats with a portal cannula. Oral gavage of the potato extract reduced the food intake in the rats, the effect being greater than with casein and a soybean β-conglycinin hydrolysate. The suppressive effect on appetite of the potato extract was attenuated by treating with a CCK-receptor antagonist (devazepide). The portal CCK concentration was increased after a duodenal administration of the potato extract to anesthetized rats. These results indicate that the potato extract suppressed the food intake in rats through CCK secretion.
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  • Markku T. SAARINEN, Sampo J. LAHTINEN, Jens F. SØRENSEN, Kirsti T ...
    2012 Volume 76 Issue 6 Pages 1135-1139
    Published: June 23, 2012
    Released: June 23, 2012
    [Advance publication] Released: June 07, 2012
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    Different ways of treating bran by baking enzymes prior to dough making and the baking process were used to increase the amount of water-soluble dietary fiber (DF) in wheat bread with added bran. Soluble DF was extracted from the bread with water and separated from the digestible material with gastrointestinal tract enzymes and by solvent precipitation. The baking enzyme mixtures tested (xylanase and glucanase/cellulase, with and without lipase) increased the amounts of soluble arabinoxylan and protein resistant to digestion. The isolated fiber was used as a growth substrate for 11 probiotic and intestinal Bifidobacterium strains, for commensal strains of Bacteroides fragilis and Escherichia coli, and for potential intestinal pathogenic strains of E. coli O157:H7, Salmonella typhimurium, and Clostridium perfringens. Fermentation analyses indicated that the tested strains had varying capacity to grow in the presence of the extracted fiber. Of the tested probiotic strains B. longum species generally showed the highest ability to utilize the fiber extracts, although the potential pathogens tested also showed an ability to grow on these fiber extracts. In sum, the enzymes used to improve the baking process for high-fiber bread can also be used to produce in situ soluble fiber material, which in turn can exert prebiotic effects on certain potentially beneficial microbes.
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  • Yumi YAMASAKI, Masao YAMASAKI, Hirofumi TACHIBANA, Koji YAMADA
    2012 Volume 76 Issue 6 Pages 1163-1168
    Published: June 23, 2012
    Released: June 23, 2012
    [Advance publication] Released: June 07, 2012
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    Fucoidan induces apoptosis by activating caspase-8 in human MCF-7 breast cancer cells, but the detailed mechanism for this is not understood. We demonstrate here that fucoidan interacted with the cell surface, and silencing the β1-integrin gene expression inhibited fucoidan-induced apoptosis accompanied by caspase-8 activation. Fucoidan induced formation of the β1-integrin-caspase-8 complex. These data indicate that β1-integrin is an important factor for the cell-surface binding of fucoidan and plays an important role in fucoidan-induced apoptosis. Fucoidan also induced recruitment of caspase-8 to the β1-integrin intracellular domain, cleaved it into the activated protein by direct combination with β1-integrin, and induced apoptosis via the caspase cascade in MCF-7 cells.
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  • Shoko KOBAYASHI, Shinta KATSUYAMA, Tamae WAGATSUMA, Shinji OKADA, Soic ...
    2012 Volume 76 Issue 6 Pages 1182-1188
    Published: June 23, 2012
    Released: June 23, 2012
    [Advance publication] Released: June 07, 2012
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    Peanut and buckwheat induce a severe allergic reaction, anaphylaxis, which is considered to be mediated by immunoglobulin E (IgE). We identified in this study a new IgE-binding epitope of the peanut allergen that cross-reacted with buckwheat. The phosphate-buffered saline-soluble fraction of buckwheat inhibited the binding between IgE and the peanut allergen. A cross-reactive peptide was isolated from the α-chymotrypsin hydrolysate of peanut. Based on the amino acid sequence and mass spectrometric analysis data, the peptide was identified as Ser-Asp-Gln-Thr-Arg-Thr-Gly-Tyr (SDQTRTGY); this sequence is identical to amino acids 2–9 in the N-terminal hydrophilic domain of oleosin 3 which is located on the surface of the lipid storage body. Synthetic SDQTRTGY was found to bind with IgE in the sera of all eight peanut-allergic patients tested. Since many foods of plant origin contain oleosin, the possibility of an anaphylactic cross-reaction in allergic patients should always be considered.
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  • Noriyuki KOHDA, Shoichiro INOUE, Tsuneyuki NODA, Takao SAITO
    2012 Volume 76 Issue 6 Pages 1195-1200
    Published: June 23, 2012
    Released: June 23, 2012
    [Advance publication] Released: June 07, 2012
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    Six healthy male subjects were treated with 0 g, 1 g, 3 g, and 0 g of chitosan for the first, second, third, and fourth of four weeks, respectively. They were administered chitosan before breakfast on the second, third, and fourth days of the week, and fecal specimens were collected corresponding to the prescribed diet consumed for breakfast on the second day to breakfast on the fourth day. Fecal excretion of dioxins and polychlorinated biphenyls (PCBs) was promoted by intake of 3 g of chitosan (p=0.0589 and p<0.05 respectively), and was positively correlated with that of fat (p<0.01 for both). We found that chitosan intake increased the fecal excretion of dioxins and PCBs, as well as that of fat, suggesting that it might be useful for reducing the adverse effects of lipophilic endocrine-disrupting chemicals.
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  • Ying-hua LIU, Yong ZHANG, Qing XU, Xiao-ming YU, Xin-sheng ZHANG, Jin ...
    2012 Volume 76 Issue 6 Pages 1213-1218
    Published: June 23, 2012
    Released: June 23, 2012
    [Advance publication] Released: June 07, 2012
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    A further investigation of the lipolysis induced by medium-chain triglyceride (MCT) was conducted on C57BL/6J mice fed with a diet containing 2% MCT or 2% long-chain triglyceride (LCT). Blood norepinephrine, body fat and blood lipid variables, and the protein or mRNA expression of the genes relevant to lipolysis were measured and analyzed in the white and brown adipose tissue (WAT, BAT). Decreased body fat and improved blood lipid profiles attributable to MCT were confirmed. A higher level of blood norepinephrine was observed with the MCT diet. The adipose triglyceride lipase (ATGL) activity and its mRNA expression, the expression of protein and mRNA of the beta 3 adrenergic receptor (β3-AR) in both WAT and BAT, and the hormone-sensitive lipase (HSL) activity and its mRNA expression in BAT were significantly increased in the mice with MCT feeding. The lipolysis induced by MCT might be partially mediated by increasing norepinephrine, thereafter signaling the up-regulation of β3-AR, ATGL, and HSL in WAT and BAT.
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Food & Nutrition Science Notes
Microbiology & Fermentation Technology Regular Papers
  • Hiroaki NISHIUCHI, Yukiko TABIRA, Kazuo YAMAGISHI
    2012 Volume 76 Issue 6 Pages 1085-1090
    Published: June 23, 2012
    Released: June 23, 2012
    [Advance publication] Released: June 07, 2012
    JOURNALS FREE ACCESS
    Traditional screening using chemicals or flow cytometry (FCM) alone is not sufficient to isolate the high glutathione (GSH)-producing yeast strains used in food production. Therefore, to improve screening efficiency, we investigated a combination of both methods. A mutated Saccharomyces cerevisiae strain was labeled with 5-chloromethylfluorescein diacetate and sorted by FCM according to emitted fluorescence intensity. Moderate GSH (1%–2%)-producing mutants were isolated, whereas high GSH (>2%)-producing mutants were not. Traditional screening using cerulenin resulted in similar findings, but a combination of both methods resulted in a 40% increase in the screening yield of high GSH-producing mutants. An analysis of model strains indicated that the ratio of high GSH-producing cells in a sample affected the FCM results. By combining FCM with traditional screening using chemicals, we succeeded in isolating high GSH-producing mutants from several parental strains.
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  • Byung-Kwan LIM, Soo-hyeon YUN, Eun-Seon JU, Chae-Ok GIL, Duk-Kyung KIM ...
    2012 Volume 76 Issue 6 Pages 1173-1176
    Published: June 23, 2012
    Released: June 23, 2012
    [Advance publication] Released: June 07, 2012
    JOURNALS FREE ACCESS
    We generated a cardiotropic replication-competent chimeric coxsackievirus B3 (CVB3) to express alcohol dehydrogenase (ADH). Although exogenously expressed ADH was found by Western blot analysis, its enzyme function was repressed. To define the factor that inhibits the enzymatic function of ADH, we introduced a site-directed mutation at the second amino acid (MGAQEF···) of the CVB3 VP0 capsid protein, effectively changing glycine to alanine. This glycine is known to be a myristoylation site during viral capsid protein maturation in infected cells. In contrast to the unmodified virus, ADH expression and enzymatic function were readily detectable in the mutated rCVB3-ADH (G2A) virus. While expression of ADH required mutation of the CVB3 VP0 myristoylation site for proper function, another chimeric virus that expresses green fluorescent protein (rCVB3-GFP (G or A)) worked independently of the myristoylation site. Indeed, infected HeLa cells displayed GFP under a fluorescent microscope. These results indicate that the myristoylation site in the VP0 capsid protein inhibited the expression of enzymatically active ADH but not GFP. VP0 myristoylation is dispensable for chimeric CVB3 virus replication.
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Microbiology & Fermentation Technology Note
Environmental Science Regular Paper
  • Boonnakhom TANGKHAVANICH, Takashi KOBAYASHI, Shuji ADACHI
    2012 Volume 76 Issue 6 Pages 1146-1149
    Published: June 23, 2012
    Released: June 23, 2012
    [Advance publication] Released: June 07, 2012
    JOURNALS FREE ACCESS
    Rice straw was separated into four parts: the upper, middle, and lower parts of the stem, and the leaf. They were treated with subcritical water at 140 to 260 °C. The yield, carbohydrate, protein, and phenolic contents were obtained as well as the UV-Vis absorption spectra and the radical scavenging activity of the extracts. The extracts obtained from the stem parts had almost the same characteristics and were different from those of the leaf part. The extracts, prepared at higher temperature, exhibited higher radical scavenging ability. The radical scavenging ability and the phenolic content showed a correlation (R2=0.92), suggesting that the phenolic substances in the extract cause its antioxidant ability.
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