Bioscience, Biotechnology, and Biochemistry
Online ISSN : 1347-6947
Print ISSN : 0916-8451
Volume 77 , Issue 6
Showing 1-42 articles out of 42 articles from the selected issue
Award Reviews
  • Hisakazu YAMANE
    2013 Volume 77 Issue 6 Pages 1141-1148
    Published: June 23, 2013
    Released: June 23, 2013
    [Advance publication] Released: June 07, 2013
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    We performed extensive functional characterization of diterpenoid phytoalexin biosynthetic genes in rice, and found that the genes for the biosynthesis of the major diterpenoid phytoalexins, phytocassanes and momilactones, are clustered on chromosomes 2 and 4, and that their expression is coordinately induced in rice cells after elicitation. Isopentenyl diphosphate, an early precursor of diterpenoid phytoalexins, was found to be synthesized through the plastidic methylerythritol phosphate pathway. We also found that chitin elicitor receptor kinase OsCERK1 and a mitogen-activated protein kinase cascade, the OsMKK4-OsMPK6 cascade, play essential roles in the elicitor-induced production of diterpenoid phytoalexins. In addition, a basic leucine zipper transcription factor, OsTGAP1, was identified as a key regulator of the coordinated expression of the clustered genes and the methylerythritol phosphate pathway genes. Naringenin 7-O-methyltransferase (OsNOMT) was also identified as a key enzyme in the biosynthesis of another major rice phytoalexin, sakuranetin.
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  • Ryouichi FUKUDA
    2013 Volume 77 Issue 6 Pages 1149-1154
    Published: June 23, 2013
    Released: June 23, 2013
    [Advance publication] Released: June 07, 2013
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    A potent ability to assimilate hydrophobic compounds, including n-alkanes and fatty acids as carbon sources, is one of important characteristics of the yeast Yarrowia lipolytica, and has been studied for both basic microbiological interest and biotechnological applications. This review summarizes recent progress on the metabolism of n-alkanes and its transcriptional control in response to n-alkanes and to fatty acids in Y. lipolytica. In the metabolism of n-alkanes, cytochromes P450ALK catalyze their initial hydroxylation to fatty alcohols, which are subsequently converted to fatty acids and utilized. The transcription of ALK1, encoding a predominant cytochrome P450ALK, is regulated in response to n-alkanes by two basic helix-loop-helix transcription activators, Yas1p and Yas2p, and Opi1-family transcription repressor Yas3p. Transcription of the genes involved in fatty acid utilization and peroxisome biogenesis is controlled by Ctf1-family Zn2Cys6 type transcription factor Por1p in response to fatty acids in Y. lipolytica.
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  • Tsutomu SATO
    2013 Volume 77 Issue 6 Pages 1155-1159
    Published: June 23, 2013
    Released: June 23, 2013
    [Advance publication] Released: June 07, 2013
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    To the best of my knowledge, only 19 cyclic and 8 linear C35 terpenes have been identified to date, and no family name was assigned to this terpene class until recently. In 2011, it was proposed that these C35 terpenes should be called sesquarterpenes. This review highlights the biosynthesis of two kinds of sesquarterpenes (C35 terpenes) that are produced via cyclization of a linear C35 isoprenoid in Bacillus and Mycobacterium species. In Bacillus species, a new type of terpene cyclase that has no sequence homology with any known terpene synthases, as well as a bifunctional terpene cyclase that biosynthesizes two classes of cyclic terpenes with different numbers of carbons as natural products, have been identified. On the other hand, in Mycobacterium species, the first bifunctional Z-prenyltransferase has been found, but a novel terpene cyclase and a unique polyprenyl reductase remain unidentified. The identification of novel enzyme types should lead to the discovery of many homologous enzymes and their products including novel natural compounds. On the other hand, many enzymes responsible for the biosynthesis of natural products have low substrate specificities in vitro. Therefore, to find novel natural products present in organisms, the multifunctionality of enzymes in the biosynthetic pathway of natural products should be analyzed.
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Organic Chemistry Regular Papers
  • Minpei KURODA, Satoshi KUBO, Yukiko MATSUO, Tomomi ATOU, Junichi SATOH ...
    2013 Volume 77 Issue 6 Pages 1186-1192
    Published: June 23, 2013
    Released: June 23, 2013
    [Advance publication] Released: June 07, 2013
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    A chemical investigation of Digitalis purpurea seeds led to the isolation of three new cardenolide glycosides (1, 8 and 11), together with 12 known cardenolide glycosides (27, 9, 10 and 1215). The structures of 1, 8 and 11 were determined by 1D and 2D NMR spectroscopic analyses and the results of an acid or enzymatic hydrolysis. The cytotoxic activity of the isolated compounds (115) against HL-60 leukemia cells was examined. Compounds 2, 9, 11 and 12 showed potent cytotoxicity against HL-60 cells with respective 50% inhibition concentration (IC50) values of 0.060, 0.069, 0.038, and 0.034 µM. Compounds 2, 9 and 11 also exhibited potent cytotoxic activity against HepG2 human liver cancer cells with respective IC50 values of 0.38, 0.79, and 0.71 µM. An investigation of the structure-activity relationship showed that the cytotoxic activity was reduced by the introduction of a hydroxy group at C-16 of the digitoxigenin aglycone, methylation of the C-3' hydroxy group at the fucopyranosyl moiety, and acetylation of the C-3' hydroxy group at the digitoxopyranoyl moiety.
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  • Jeong-Oh YANG, Naoya NAKAYAMA, Kyohei TODA, Shinichi TEBAYASHI, Chul-S ...
    2013 Volume 77 Issue 6 Pages 1258-1261
    Published: June 23, 2013
    Released: June 23, 2013
    [Advance publication] Released: June 07, 2013
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    We elucidate the mechanism for inducing the production of ovicidal benzyl benzoate by Japonica rice varieties to kill eggs of the whitebacked planthopper, Sogatella furcifera (Horváth), lying in the rice plant. Even when subjected to physical damage by a needle or damage with water, the rice plant produced no benzyl benzoate. However, significant benzyl benzoate was produced when the plant was damaged with a methanol extract or homogenate of S. furcifera. The extract of the male did not induce the production of benzyl benzoate, but that of the female did. We concluded from these results that benzyl benzoate was induced by some elicitor(s) in the female of S. furcifera.
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Organic Chemistry Notes
Organic Chemistry Communication
  • Shin SHIMOMURA, Shuho OYAMA, Kyohei NAKANO, Morifumi HASEGAWA, Hiroaki ...
    2013 Volume 77 Issue 6 Pages 1354-1357
    Published: June 23, 2013
    Released: June 23, 2013
    [Advance publication] Released: June 07, 2013
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    Stereoselective synthesis of a promising flower-inducing 9,10-ketol octadecadienoic acid (KODA) analog, (9R,12S,13R,15Z)-9-hydroxy-12,13-methylene-10-oxooctadec-15-enoic acid, was designed to obtain the desired stereoisomer via coupling between chiral sulfone and aldehyde segments. A known chiral cyclopropane derivative was converted to the sulfone segment via carbon-chain elongation and sulfonylation. Dec-9-en-1-ol was converted to the aldehyde segment, whose C-9 configuration was introduced by Sharpless asymmetric dihydroxylation. Coupling of the both segments and subsequent assembly gave the desired (9R,12S,13R,15Z)-analog. The (9S,12S,13R,15Z)-analog was also synthesized by using the enatiomeric aldehyde segment. This strategy made it possible to synthesize the remaining stereoisomeric analogs.
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Biochemistry & Molecular Biology Regular Papers
  • Takafumi YAMASHINO, Saori YAMAWAKI, Emi HAGUI, Kai ISHIDA, Hanayo UEOK ...
    2013 Volume 77 Issue 6 Pages 1179-1185
    Published: June 23, 2013
    Released: June 23, 2013
    [Advance publication] Released: June 07, 2013
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    Supplementary material
    Plant circadian clock generates rhythms with a period close to 24 h, and it controls a wide variety of physiological and developmental events, including the transition to reproductive growth (or flowering). During the last decade, significant research progress in Arabidopsis thaliana has been made in defining the molecular mechanism by which the circadian clock regulates flowering time in response to changes in photoperiod. In Lotus japonicus, we have found that LjFTa, which encodes a ortholog of the Arabidopsis FLOWERING LOCUS T (FT), plays an important role in the promotion of flowering, but it is not clear how the expression of LjFTa is regulated in L. japonicus. Based on current knownledge of photoperiodic control of flowering time in A. thaliana, here we examined whether a microRNA is involved in the activation of LjFTa in L. japonicus. Two putative L. japonicus genes that are responsible for the production of miR172 (designated LjmiR172a and LjmiR172b) were cloned. Overexpression of LjmiR172a/b in A. thaliana resulted in markedly accelerated flowering through enhancement of the expression of FT, concomitantly reducing the expression level of TARGET OF EARLY ACTIVATION TAGGED 1 (TOE1) transcripts, the protein product of which functions as a transcriptional repressor of FT. These results suggest that LjmiR172 genes play a positive role in the LjFTa-mediated promotion of flowering in L. japonicus.
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  • Wu-Jun GAO, Shu-Fen LI, Guo-Jun ZHANG, Ning-Na WANG, Chuan-Liang DENG, ...
    2013 Volume 77 Issue 6 Pages 1193-1199
    Published: June 23, 2013
    Released: June 23, 2013
    [Advance publication] Released: June 07, 2013
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    To identify rapidly a number of genes probably involved in sex determination and differentiation of the dioecious plant Asparagus officinalis, gene expression profiles in early flower development for male and female plants were investigated by microarray assay with 8,665 probes. In total, 638 male-biased and 543 female-biased genes were identified. These genes with biased-expression for male and female were involved in a variety of processes associated with molecular functions, cellular components, and biological processes, suggesting that a complex mechanism underlies the sex development of asparagus. Among the differentially expressed genes involved in the reproductive process, a number of genes associated with floral development were identified. Reverse transcription-PCR was performed for validation, and the results were largely consistent with those obtained by microarray analysis. The findings of this study might contribute to understanding of the molecular mechanisms of sex determination and differentiation in dioecious asparagus and provide a foundation for further studies of this plant.
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  • Ming XIANG, Jingli LU, Chengliang ZHANG, Yan LAN, Hong ZHOU, Xiping LI ...
    2013 Volume 77 Issue 6 Pages 1200-1206
    Published: June 23, 2013
    Released: June 23, 2013
    [Advance publication] Released: June 07, 2013
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    Urtica dentata Hand (UDH) is traditionally used in the Alpine region as a herbal medicine. Immunotherapy using total coumarins (TC) of UDH has been proposed, yet the cellular and molecular mechanisms remain incompletely characterized. Additionally, there is no method available for the quantification of the main coumarins in UDH. We describe maturation-resistant, TC-conditioned dendritic cell (DC), which expressed much lower MHC class II (I-Ak) and CD86, showed reduced capacity to stimulate effector T cell responses and upregulated PD-Ll (programmed death ligand-1). TC-DC-stimulated regulatory cells (Treg) were superior alloantigen-specific suppressor of the T effector response as compared to those stimulated by control (CTR)-DC. Furthermore, TC-conditioned DC increased the levels of Foxp3 and CTLA-4 in the CD25 T cell population. TC-DC downregulated toll like receptor 4 (TLR4) protein expression in response to LPS. This indicates that down-regulation of TLR4 in response to TC on DC is a critical signaling pathway that regulates the phenotype and function of DC. We also established a sensitive and specific high-performance liquid chromatography-diodearray detection-mass spectrometry (HPLC-DAD-MS) method for simultaneous identification of its main coumarins, 6,6',7,7'-tetramethoxyl-8,8'-biscoumarin (1), 7,7'-dihydroxy-6,6'-dimethoxy-8,8'-biscoumarin (2), 7,7'-dimethoxy-6,6'-biscoumarin (3), and scoparone (4). A demonstration of this mechanism and the method for identification and quantification of TC in UDH endorsed their potential as a tolerance-promoting herbal medicine to prevent or treat transplantation rejection and autoimmune diseases.
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  • Min YOU, Yanning LIU, Yingwei CHEN, Jiyuan GUO, Jun WU, Yajuan FU, Ron ...
    2013 Volume 77 Issue 6 Pages 1207-1213
    Published: June 23, 2013
    Released: June 23, 2013
    [Advance publication] Released: June 07, 2013
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    Due to the great diversity in protein expression productivity, a customized transient gene expression (TGE) method was used in the present study to optimize transient expression of three antibodies. Several factors, including host cells, temperature, valproic acid (VPA) treatment, various vectors, and additives were optimized independently and then combined to form a customized TGE protocol for each antibody. In the event, the optimized TGE conditions for three antibodies were different from each other. Compared with the TGE in CHO-S cells by pCDNA3.1 expression vector, the expression productivities of 8C11 cAb, 37 hAb, and 10F7 cAb showed 16-fold, 293-fold, and 19-fold increases respectively by the customized TGE method. For 8C11 cAb, coexpressing L-chain and H-chain on different plasmids led to higher yields. The customized TGE method is an alternative approach that can greatly improve the expression productivity of a variety of recombinant proteins.
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  • Jin-yu ZHAO, Jia-huang LI, Zheng ZHANG, Shu-yi ZHANG, Min QU, Zi-qian ...
    2013 Volume 77 Issue 6 Pages 1251-1257
    Published: June 23, 2013
    Released: June 23, 2013
    [Advance publication] Released: June 07, 2013
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    The bar-headed goose, a specialized high-altitude species, has a capacity for high oxygen uptake from a hypoxic environment. It thus has a higher oxygen affinity than other bird species of lower-altitude environments. Oxygen affinity is determined by molecular structures and genetic mutations of hemoglobin (Hb), which can also influence the coordinating structures and dynamics of oxygen-Hb. To explore the structural differences in Hbs as between high and low altitude species, photolysis dynamic parameters, including quantum yield, enthalpy, and conformational volume changes in carboxy-Hbs (HbCO) for the bar-headed goose and low altitude counterparts (the Chinese goose and chicken) were investigated by the laser pumping-probing technique and photoacoustic calorimetry. Comparing the photolysis results for HbCO of the three species, the enthalpy and conformational volume changes of the bar-headed goose were much smaller than those of the others, although the quantum yields of all three species are similar. To explain the possible mechanisms of these differences, modifications of salt bridges and key residue mutations at the α β subunit interfaces of the proteins are described and discussed briefly.
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  • Megumi MAEDA, Naoto TAKEDA, Aya MANO, Maomi YAMANISHI, Mariko KIMURA, ...
    2013 Volume 77 Issue 6 Pages 1269-1274
    Published: June 23, 2013
    Released: June 23, 2013
    [Advance publication] Released: June 07, 2013
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    In our previous report (M. Okano, et al., Clin. Exp. Allergy, 34, 770–778 (2004)), we found that free plant complex type N-glycans suppressed the production of IL4 from Th2 cells of Japanese cedar pollinosis patients, suggesting that plant complex type N-glycan can be used as a leading compound for developing immuno-pharmaceuticals. Although immunoreactive plant complex type N-glycans occur ubiquitously on glycoproteins expressed in plants, an appropriate procedure has not been established to prepare non-labeled immunoreactive glycans or glycopeptides bearing structurally homologous immunoreactive glycans in large amounts. In this study, therefore, we developed a new preparative procedure for the large-scale preparation of Asn-glycopeptide bearing plant complex type N-glycan using a combination of gel-filtration and the hydrophilic partitioning method. By this new method, about 103 mg of Asn-glycopeptide bearing the antigenic N-glycans was obtained from 1.9 kg of shelled Ginkgo biloba seeds.
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  • Tetsuya SAYO, Yoshinori SUGIYAMA, Shintaro INOUE
    2013 Volume 77 Issue 6 Pages 1282-1286
    Published: June 23, 2013
    Released: June 23, 2013
    [Advance publication] Released: June 07, 2013
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    Supplementary material
    Carotenoids have been reported to have potent antioxidant activities and to protect tissues and cells from certain diseases and environmental insults. The molecular mechanism of the action of provitamin A carotenoids such as β-carotene and β-cryptoxanthin is mediated in part by retinoic acid, an active form of provitamin A, but the molecular basis of the biological activities of non-provitamin A carotenoids such as lutein, zeaxanthin, and astaxanthin is not fully understood. In this study, we investigated to determine whether the actions of non-provitamin A carotenoids are mediated via retinoid signaling by monitoring retinoic acid receptor (RAR)-dependent hyaluronan production in cultured human keratinocytes. Not only β-carotene and β-cryptoxanthin, but also lutein, zeaxanthin, and astaxanthin, upregulated HAS3 gene expression and were followed by hyaluronan synthesis. We found that LE540, an antagonist of retinoic acid receptors, abolished lutein dependent hyaluronan synthesis and that lutein significantly increased retinoic acid responsive element (RARE)-driven transcript acitivity. In addition, we found that citral, an inhibitor of retinal dehydrogenases, decreased lutein-stimulated hyaluronan synthesis, indicating that lutein metabolites rather than lutein itself act as an RAR ligand in RAR-mediated transcription activity in keratinocytes. A series of non-provitamin A can be substituted for retinoids and should be considered as a potential means of improving skin health.
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  • Tomoko NIWA, Tatsuhiko KONDO, Michi NISHIZAWA, Ryoko KAJITA, Tatsuo KA ...
    2013 Volume 77 Issue 6 Pages 1287-1295
    Published: June 23, 2013
    Released: June 23, 2013
    [Advance publication] Released: June 07, 2013
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    Supplementary material
    Stomatal development in Arabidopsis epidermis is both positively and negatively regulated by a family of Cys-rich peptides, EPIDERMAL PATTERNING FACTOR LIKEs (EPFLs). We synthesized biologically active synthetic EPFL5 (sEPFL5) peptide, which reduced the number of stoma in leaves and cotyledons. The sEPFL5 possesses three disulfide bonds at positions identical to those of a positive development factor, stomagen. Application of sEPFL5 had little inhibitory effect on protodermal cells entering the stomatal lineage, but did inhibit the maintenance of meristemoid activity, resulting in the differentiation of arrested meristemoids into pavement cells. This phenotype was enhanced in the too many mouths (tmm) mutant background. RNA analysis revealed that sEPFL5 application halved SPEECHLESS expression and abolished MUTE expression in tmm mutants, explaining the phenotype observed. The action of sEPFL5 was mediated by ERECTA family receptors. We propose that EPFL5 functions to establish the differentiation of stomatal lineage cells to pavement cells.
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Biochemistry & Molecular Biology Notes
Biochemistry & Molecular Biology Communications
  • Fumiaki ITO, Hidehiro CHISHIKI, Shinya FUSHINOBU, Takayoshi WAKAGI
    2013 Volume 77 Issue 6 Pages 1344-1348
    Published: June 23, 2013
    Released: June 23, 2013
    [Advance publication] Released: June 07, 2013
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    Supplementary material
    Aldehyde dehydrogenase ST0064, the closest paralog of previously characterized allosteric non-phosphorylating glyceraldehyde-3-phosphate (GAP) dehydrogenase (GAPN, ST2477) from a thermoacidophilic archaeon, Sulfolobus tokodaii, was expressed heterologously and characterized in detail. ST0064 showed remarkable activity toward succinate semialdehyde (SSA) (Km of 0.0029 mM and kcat of 30.0 s−1) with no allosteric regulation. Activity toward GAP was lower (Km of 4.6 mM and kcat of 4.77 s−1), and previously predicted succinyl-CoA reductase activity was not detected, suggesting that the enzyme functions practically as succinate semialdehyde dehydrogenase (SSADH). Phylogenetic analysis indicated that archaeal SSADHs and GAPNs are closely related within the aldehyde dehydrogenase superfamily, suggesting that they are of the same origin.
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  • Guiping MOU, Kang WANG, Donglin XU, Guohui ZHOU
    2013 Volume 77 Issue 6 Pages 1349-1353
    Published: June 23, 2013
    Released: June 23, 2013
    [Advance publication] Released: June 07, 2013
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    Three frequently-used reverse transcription-quantitative polymerase chain reaction (RT-qPCR)-based miRNA detection methods, stem-loop RT-qPCR, poly(A)-tailing RT-qPCR, and miQPCR, were evaluated using seven selected rice miRNAs. The results revealed that miRNA abundance and sequence characteristics can affect capability of detection. The stem-loop amplification technique detected highly and moderately abundant miRNAs. The poly(A)-tailing method detected both highly abundant and sparsely present miRNAs, but failed to detect miRNAs with a hairpin structure. Only a few miRNAs were detectable by the miQPCR method. We suggest that a combination of methods should be used for reliable quantitative investigation of miRNAs.
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Food & Nutrition Science Regular Papers
  • Yumiko NAKANISHI, Shiori KAWAMURA, Satomi TSUTSUURA, Yuko SHIMAMURA, M ...
    2013 Volume 77 Issue 6 Pages 1160-1165
    Published: June 23, 2013
    Released: June 23, 2013
    [Advance publication] Released: June 07, 2013
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    The aim of this study was to determine why food poisoning bacteria attached to cut cabbage are not efficiently disinfected by sodium hypochlorite (NaClO). Pretreatment of shredded cabbage with diethyl ether definitely decreased the survival numbers of Escherichia coli O157:H7 and Salmonella spp. after disinfection with 100 ppm of NaClO. The density of E. coli O157:H7 at the cut edge of a cabbage section was larger than that on the surface. The residual ratio of attached bacteria at the cut edge after NaClO disinfection was significantly higher than that on the surface. Microscopical observation indicated that the cut edge of shredded cabbage pretreated with diethyl ether was almost closed, resulting in a decrease in bacterial infiltration. Pretreatment of shredded cabbage with a higher concentration of NaClO to penetrate it more deeply significantly decreased the numbers of surviving bacteria after NaClO disinfection. Based on these results, we concluded that the bacteria attached to cut cabbage were not efficiently disinfected by NaClO, because not enough NaClO deeply infiltrated into the cut edges, and hence not enough came in contact with the bacteria.
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  • Kumiko NAKANO, Haruka KUBO, Shigenobu MATSUMURA, Tsukasa SAITO, Tohru ...
    2013 Volume 77 Issue 6 Pages 1166-1170
    Published: June 23, 2013
    Released: June 23, 2013
    [Advance publication] Released: June 07, 2013
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    The present study explored the possibility that aroma components generated by the oxidation of olive oil may enhance the palatability of olive oil. Using a mouse behavioral model, we found that olive oil oxidized at room temperature for 3 weeks after opening the package, and heated olive oil were both significantly preferred over non-oxidized olive oil. Furthermore, this preference was enhanced with an additive of oxidized refined olive oil flavoring preparation at a certain concentration. These results suggest that the aroma of oxidized fat might be present in most fats, and might act as a signal that makes possible the detection of fats or fatty acid sources.
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  • Nauman KHALID, Isao KOBAYASHI, Marcos A. NEVES, Kunihiko UEMURA, Mitsu ...
    2013 Volume 77 Issue 6 Pages 1171-1178
    Published: June 23, 2013
    Released: June 23, 2013
    [Advance publication] Released: June 07, 2013
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    This study sought to encapsulate a high concentration of L-ascorbic acid, up to 30% (w/v), in the inner aqueous phase of water-in-oil-water (W/O/W) emulsions with soybean oil as the oil phase. Two-step homogenization was conducted to prepare W/O/W emulsions stabilized by a hydrophobic emulsifier and 30% (v/v) of W/O droplets stabilized by a hydrophilic emulsifier. First-step homogenization prepared W/O emulsions with an average aqueous droplet diameter of 2.0 to 3.0 μm. Second-step homogenization prepared W/O/W emulsions with an average W/O droplet diameter of 14 to 18 μm and coefficients of variation (CVs) of 18% to 25%. The results indicated that stable W/O/W emulsions containing a high concentration of L-ascorbic acid were obtained by adding gelatin and magnesium sulfate in the inner aqueous phase and glucose in both aqueous phases. L-Ascorbic acid retention in the W/O/W emulsions was 40% on day 30 and followed first-order kinetics.
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  • Yukinobu NAKAMURA, Koshiro MIGITA, Akihiro OKITANI, Masanori MATSUISHI
    2013 Volume 77 Issue 6 Pages 1214-1218
    Published: June 23, 2013
    Released: June 23, 2013
    [Advance publication] Released: June 07, 2013
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    We examined the mode of IMP and pyrophosphate enhancement of myosin and actin extraction from porcine meat. Extractabilities were determined after homogenates, prepared by adding 9 volumes of 0.3, 0.4, or 0.5 M NaCl solutions containing 0 to 36 mM IMP and 0 to 9 mM tetrapotassium pyrophosphate (KPP) to minced pork, were incubated at 4 °C for 0 or 12 h. Irrespective of the NaCl concentrations, IMP-induced extraction of both proteins increased with increasing extraction time. In contrast, that of KPP did not. When 0.3 M NaCl solutions containing both IMP and KPP were used, the solutions with 1.5 mM KPP showed marked enhancement of IMP-induced myosin and actin extraction. Incorporating these results with our previously published data (Nakamura et al., Biosci. Biotechnol. Biochem., 76, 1611–1615 (2012)), we hypothesized that IMP and KPP have the ability to release thick and thin filaments from restraints in myofibrils, in addition to the ability to dissociate actomyosin into myosin and actin, and that the restraint-releasing ability of IMP is dependent on reaction time and NaCl concentration while that of KPP is not.
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  • Hiroyuki TAKEUCHI, Taiki KUTSUWADA, Yutaka SHIROKAWA, Sumiko HARADA, M ...
    2013 Volume 77 Issue 6 Pages 1219-1222
    Published: June 23, 2013
    Released: June 23, 2013
    [Advance publication] Released: June 07, 2013
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    The World Health Organization (WHO) has recommended that trans fatty acid (TFA) intake should be less than 1% of total energy intake, but few data are available as to the influence of energy TFA intake of as low as 1% on blood cholesterol levels. A randomized, double-blind, parallel trial was conducted to assess the effects of 1% TFA dietary supplementation on serum cholesterol levels in healthy young women. Sixty-five volunteers consumed cookies containing 1% (TFA) or 0.04% (control) energy of TFA for 4 weeks and blood was harvested after overnight fasting. There were no significant differences in serum LDL- or HDL-cholesterol levels between the two groups. The hemoglobin A1c level was not influenced by dietary TFA. These results suggest that energy of TFAs at less than 1% has little effect on serum cholesterol or hemoglobin A1c levels in healthy young women. This confirms the correctness of the WHO recommendation.
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  • Hirofumi INOUE, Mari MAEDA-YAMAMOTO, Atsushi NESUMI, Takuji TANAKA, Ak ...
    2013 Volume 77 Issue 6 Pages 1223-1228
    Published: June 23, 2013
    Released: June 23, 2013
    [Advance publication] Released: June 07, 2013
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    Our previous study indicated that a diet containing a high dose (1%) of green tea polyphenols (GTPs) disrupted liver and kidney function via a reduction in antioxidant enzyme and heat shock protein (HSP) levels in both colitis and non-treated ICR mice. In the present study, we assessed the effects of 0.01%, 0.1%, and 1% dietary GTPs on liver and kidney physiological functioning in dextran sulfate sodium (DSS)-exposed and normal mice. GTPs at 0.01% and 0.1% significantly suppressed DSS-increased serum aspartate 2-oxoglutarate aminotransferase (AST) and alanine aminotransferase (ALT) levels. In contrast, GTPs at 1% increased kidney weight, serum creatinine levels, and thiobarbituric acid-reactive substances (TBARs) in both the kidney and the liver in normal mice, as compared with DSS-exposed mice. GTPs at 0.01% and 0.1% remarkably upregulated the expression of heme oxygenase-1 (HO-1) and heat shock protein 70 (HSP70) mRNA in the liver and kidney of mice exposed to DSS, whereas GTPs at 1% abolished it. Our results indicate that low and medium doses of GTPs have beneficial effects on DSS-induced hepatotoxicity and nephrotoxicity via upregulation of self-protective enzymes, while these effects disappeared at a high dose.
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  • Tomomi ITO-NAGAHATA, Chiaki KURIHARA, Miki HASEBE, Akiko ISHII, Kaori ...
    2013 Volume 77 Issue 6 Pages 1229-1235
    Published: June 23, 2013
    Released: June 23, 2013
    [Advance publication] Released: June 07, 2013
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    Resveratrol (RSV), 3,5,4'-trihydroxy-trans-stilbene, is known to have many beneficial physiological activities. We have synthesized several stilbene anlogues and have reported that the hydroxyl group in the 4' position of RSV exhibited strong radical scavenging action. Using stilbene analogs, we investigated the structure of RSV to explain its protective effect against obesity and type 2 diabetes. All six analogs used in this study inhibited the differentiation of 3T3-L1 adipocytes. 3-Hydroxy-trans stilbene (3(OH)ST), and 3,4'-dihydroxy-trans stilbene (3,4'(OH)2ST) increased glucose uptake and induced adenosine monophosphate kinase (AMPK) phosphorylation in C2C12 myotubes independently of insulin. An in vivo study using mice fed high-fat diets indicated that 3(OH)ST was more effective than RSV in improving insulin resistance. In conclusion, RSV and its derivatives, particularly 3(OH)ST, inhibited adipocyte differentiation and enhanced glucose uptake in the myotubes, resulting in a reduction of obesity and an improvement in glucose tolerance in vivo.
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Food & Nutrition Science Notes
Microbiology & Fermentation Technology Regular Papers
  • Dali LI, Zhen ZENG, Junfang YANG, Peng WANG, Lei JIANG, Jing FENG, Che ...
    2013 Volume 77 Issue 6 Pages 1236-1239
    Published: June 23, 2013
    Released: June 23, 2013
    [Advance publication] Released: June 07, 2013
    JOURNALS FREE ACCESS
    Benzoylformate is used widely as an organic synthetic intermediate. Mandelate racemase and mandelate dehydrogenase are two enzymes used in producing benzoylformate from racemic mandelate in microbial metabolism. In the present work, the genes encoding mandelate racemase and mandelate dehydrogenase from Pseudomanas aeruginosa strain NUST were cloned and expressed in Escherichia coli to convert racemic mandelate to benzoylformate. The use of whole resting cells of recombinant E. coli allowed the conversion of 65.7 mM solution of racemic mandelate to benzoylformate at a yield of 98.9% in 45 h. The process is a promising alternative for the production of benzoylformate.
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  • Min-Ho SEO, Bi-Na KIM, Kyoung-Rok KIM, Ki Won LEE, Choong-Hwan LEE, De ...
    2013 Volume 77 Issue 6 Pages 1245-1250
    Published: June 23, 2013
    Released: June 23, 2013
    [Advance publication] Released: June 07, 2013
    JOURNALS FREE ACCESS
    Supplementary material
    Aspergillus oryzae KACC 40247 was selected from among 60 fungal strains as an effective 7,8,4'-trihydroxyisoflavone (8-hydroxydaidzein)-producing fungus. The optimal culture conditions for production by this strain in a 7-L fermentor were found to be 30 °C, pH 6, and 300 rpm. Under these conditions, A. oryzae KACC 40247 produced 62 mg/L of 8-hydroxydaidzein from soybean extract in 30 h, with a productivity of 2.1 mg/L/h. These are the highest production and productivity for 8-hydroxydaidzein ever reported. To increase production, several concentrations of daidzin and of daidzein as precursor were added at several culture times. The optimal addition time and concentration for daidzin were 12 h and 1,248 mg/L, and those for daidzein were 12 h and 254 mg/L respectively. Maximum production and productivity for 8-hydroxydaidzein with the addition of daidzein were 95 mg/L and 3.2 mg/L/h respectively, and those with the addition of daidzin were 160 mg/L and 4.4 mg/L/h respectively.
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  • Chitwadee PHITHAKROTCHANAKOON, Verawat CHAMPREDA, Sei-ichi AIBA, Kusol ...
    2013 Volume 77 Issue 6 Pages 1262-1268
    Published: June 23, 2013
    Released: June 23, 2013
    [Advance publication] Released: June 07, 2013
    JOURNALS FREE ACCESS
    Short-chain-length medium-chain-length polyhydroxyalkanoate (SCL-MCL PHA) copolymers are promising as bio-plastics with properties ranging from thermoplastics to elastomers. In this study, the hybrid pathway for the biosynthesis of SCL-MCL PHA copolymers was established in recombinant Escherichia coli by co-expression of β-ketothiolase (PhaARe) and NADPH-dependent acetoacetyl-CoA reductase (PhaBRe) from Ralstonia eutropha together with PHA synthases from R. eutropha (PhaCRe), Aeromonas hydrophila (PhaCAh), and Pseudomonas putida (PhaC2Pp) and with (R)-specific enoyl-CoA hydratases from P. putida (PhaJ1Pp and PhaJ4Pp), and A. hydrophila (PhaJAh). When glycerol supplemented with dodecanoate was used as primary carbon source, E. coli harboring various combinations of PhaABCJ produced SCL-MCL PHA copolymers of various monomer compositions varying from C4 to C10. In addition, polymer property analysis suggested that the copolymers produced from this recombinant source have thermal properties (lower glass transition and melting temperatures) superior to polyhydroxybutyrate homopolymer.
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  • Wei SHENG, Shuichi YAMASHITA, Akinori OHTA, Hiroyuki HORIUCHI
    2013 Volume 77 Issue 6 Pages 1275-1281
    Published: June 23, 2013
    Released: June 23, 2013
    [Advance publication] Released: June 07, 2013
    JOURNALS FREE ACCESS
    Supplementary material
    In this study, we identified seven chitin synthase-encoding genes in the genome of the dimorphic yeast Yarrowia lipolytica. Three encoded chitin synthases with myosin motor-like domains at their N-termini, and we designated these CSM1 to CSM3, whereas four were identified as CHS1 to CHS4. To investigate the functions of these seven genes, we constructed and characterized their deletion mutants. The chs2Δ mutant formed chained cells in which daughter cells were connected with mother cells and had abnormally thick septa at the bud neck. The chs4Δ mutant showed remarkably reduced chitin content in its cell wall. The chs2Δ, csm1Δ, and csm2Δ mutants were found to be highly sensitive to chitin binding dyes, calcofluor white (CFW) and Congo red, whereas the chs4Δ mutant was resistant to CFW. These results suggest that Chs2 and Chs4 play major roles in septum formation and cell wall chitin synthesis respectively, whereas Csm1 and Csm2 are involved in the maintenance of cell wall architecture and/or cell wall integrity. The populations of filamentous cells, a type of cell population that are defined by the lengths of the cellular long and short axes, decreased in the chs3Δ mutant, suggesting that Chs3 is involved in cellular morphogenesis.
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Environmental Science Regular Paper
  • Osamu HAYASHI, Maiko KAMESHIRO, Kiyoshi SATOH
    2013 Volume 77 Issue 6 Pages 1240-1244
    Published: June 23, 2013
    Released: June 23, 2013
    [Advance publication] Released: June 07, 2013
    JOURNALS FREE ACCESS
    The fate of [14C]heptachlor in Saitama soil and the degradation of [14C]heptachlor in four Japanese field soils over 112 d after application were investigated. Heptachlor was degraded mainly to cis-heptachlor epoxide by a biotic process and to 1-hydroxychlordene by an abiotic process in the field soils. Volatilization of heptachlor and cis-heptachlor epoxide from the soil was observed over the experimental period. The amount of 1-hydroxychlordene produced in the soils appeared to be related to the soil water contents. Because heptachlor and heptachlor epoxides are predicted to volatilize to the atmosphere and to persist in soils, these compounds are thought to spread among Japanese environmental compartments even after a ban on their use.
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Environmental Science Note
  • Nicola MANZELLA, Massimo BRACCI, Sara STAFFOLANI, Elisabetta STRAFELLA ...
    2013 Volume 77 Issue 6 Pages 1296-1298
    Published: June 23, 2013
    Released: June 23, 2013
    [Advance publication] Released: June 07, 2013
    JOURNALS FREE ACCESS
    The circadian clock can regulate the metabolic process of xenobiotics, but little is known as to circadian rhythms can be perturbed by xenobiotics. Styrene is a organic chemical widely used in occupational settings. The effects of styrene on the circadian genes of HuDE cells were evaluated after serum-shocking synchronization. A subtoxic dose of 100 µM of styrene altered the expression of clock genes BMAL1, PER2, PER3, CRY1, CRY2, and REV-ERB-α.
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