Bioscience, Biotechnology, and Biochemistry
Online ISSN : 1347-6947
Print ISSN : 0916-8451
Volume 70 , Issue 1
Showing 1-45 articles out of 45 articles from the selected issue
Review
  • Chiharu NISHIYAMA
    2006 Volume 70 Issue 1 Pages 1-9
    Published: 2006
    Released: January 23, 2006
    JOURNALS FREE ACCESS
    Transcriptional regulation for the genes encoding α- and β-chains of the high-affinity receptor for IgE (FcεRI) have been analyzed in mast cells and regulatory mechanisms are beginning to be elucidated. Transcription factors GATA-1 and PU.1 cooperatively transactivate the α-chain gene, and three transcription factors, GATA-1, Oct-1, and MZF-1, are involved in regulation of β-chain gene expression. No single nucleotide polymorphisms (SNPs) that are functionally related to the allergic diseases have been identified in coding regions of the α- and β-chain genes in a definitive way. However, recent studies on SNPs in the promoter regions have revealed that these genes are probable candidates for new types of allergy-related genes whose transcription levels are affected by transcription factors which discriminate SNPs in the promoters. Another interesting finding on transcription factors functioning in mast cells is that the expression level of PU.1 determines cell fate between mast cells and monocytes.
    Download PDF (239K)
  • Nobuo KATO, Hiroya YURIMOTO, Rudolf K. THAUER
    2006 Volume 70 Issue 1 Pages 10-21
    Published: 2006
    Released: January 23, 2006
    JOURNALS FREE ACCESS
    3-Hexulose-6-phosphate synthase (HPS) and 6-phospho-3-hexuloisomerase (PHI) are the key enzymes of the ribulose monophosphate pathway. This pathway, which was originally found in methylotrophic bacteria, is now recognized as a widespread prokaryotic pathway involved in formaldehyde fixation and detoxification. Recent progress, involving biochemical and genetic approaches in elucidating the physiological functions of HPS and PHI in methylotrophic as well as non-methylotrophic bacteria are described in this review. HPS and PHI orthologs are also found in a variety of archaeal strains. Some archaeal HPS orthologs are fused with other genes to form single ORF (e.g., the hps-phi gene of Pyrococcus spp. and the faeB-hpsB gene of Methanosarcina spp). These fused gene products exhibit functions corresponding to the individual enzyme activities, and are more efficient than equivalent systems made up of discrete enzymes. Recently, a novel metabolic function for HPS and PHI has been proposed in which these enzymes catalyze the reverse reaction for the biosynthesis of pentose phosphate in some archaeal strains. Thus the enzyme system plays a different role in bacteria and archaea by catalyzing the forward and reverse reactions respectively.
    Download PDF (190K)
Analytical Chemistry Regular Papers
  • Ryoji YAMADA, Masaki KOZONO, Takashi OHMORI, Fumiki MORIMATSU, Masahik ...
    2006 Volume 70 Issue 1 Pages 54-65
    Published: 2006
    Released: January 23, 2006
    JOURNALS FREE ACCESS
    A simple and rapid method using liquid chromatography coupled with electrospray ionization tandem mass spectrometry (LC/MS/MS) for the simultaneous determination of 130 veterinary drugs and their metabolites in bovine, porcine, and chicken muscle was developed. The drugs (1 to 10 ng/g, in muscle) were extracted from bovine, porcine, or chicken muscles with acetonitrile-methanol (95:5, v/v), and the extracts were delipidated with n-hexane saturated with acetonitrile. The extracts were evaporated, dissolved with methanol, analyzed by liquid chromatography with gradient elution on a C18 column, and determined by electrospray ionization tandem mass spectrometry. The detection limits ranged from 0.03 to 3 ng/g. The quantitation limits ranged from 0.1 to 10 ng/g. One hundred eleven, 122, and 123 drugs from bovine, porcine, and chicken muscle respectively showed recoveries between 70 and 110%.
    Download PDF (285K)
  • Norifumi SAGAWA, Takashi TAKINO, Shin KUROGOCHI
    2006 Volume 70 Issue 1 Pages 230-236
    Published: 2006
    Released: January 23, 2006
    JOURNALS FREE ACCESS
    A selective and speedy LC–MS/MS method was developed to determine six trichothecene mycotoxins (nivalenol, deoxynivalenol, fusarenon X, 15-acetyldeoxynivalenol, 3-acetyldeoxynivalenol, and T-2 toxin) in rice medium where Fusarium graminearum were cultivated for in vitro tests. The analytes were extracted from the rice medium with acetonitrile/water (85/15, v/v), and diluted with acetonitrile/water (5/95, v/v) in order to minimize the effects of matrices. Diluted solutions were analyzed by LC–MS/MS with electrospray ionization (ESI) interface in negative or positive ion mode and the multiple reaction monitoring mode. Recovery rates were 76–106% with a spiked level at 1–6 μg/kg of mycotoxins that corresponded to the limit of quantitation. The method was applied to study the time courses of trichothecene production and the biomass of fungi by three Fusarium graminearum strains. Three strains have different mycotoxin biosynthesis pathways, wFg14 and 03E-1 were DON producer, and 03N-1 was NIV producer.
    Download PDF (228K)
Organic Chemistry Regular Paper
  • Yoichi NOGATA, Koji SAKAMOTO, Hiroyuki SHIRATSUCHI, Toshinao ISHII, Ma ...
    2006 Volume 70 Issue 1 Pages 178-192
    Published: 2006
    Released: January 23, 2006
    JOURNALS FREE ACCESS
    An HPLC analysis was performed on the concentrations of flavonoids in 42 species and cultivars of the Citrus genus and those of two Fortunella and one Poncirus species according to the classification system established by Tanaka. The composition of 8 flavanones and 9 flavone/ols for these species was determined in the albedo, flavedo, segment epidermis and juice vesicle tissues, and those in the fruit and peel tissues were calculated from the composition data of the tissues. A principal component analysis showed that such neohesperidosyl flavonoids as neoeriocitrin, naringin, neohesperidin, and rhoifolin had large factor loading values in the first principal component for each tissue. The flavonoid composition of citrus fruits was approximately the same within each section of Tanaka’s system, except for the species in the Aurantium section and those with a peculiar flavonoid composition such as Bergamot (C. bergamia), Marsh grapefruit (C. paradisi), Sour orange (C. aurantium), and Shunkokan (C. shunkokan). The Aurantium section included both naringin-rich and hesperidin-rich species.
    Download PDF (502K)
Organic Chemistry Notes
Biochemistry & Molecular Biology Regular Papers
  • Surenjav UNURSAIKHAN, Xiaojuan XU, Fanbo ZENG, Lina ZHANG
    2006 Volume 70 Issue 1 Pages 38-46
    Published: 2006
    Released: January 23, 2006
    JOURNALS FREE ACCESS
    Four water-insoluble (1→3)-α-D-glucans, coded L-II1, L-II2, L-II3 and L-II4, with different molecular weights were isolated from four kinds of fruiting bodies of Lentinus Edodes. The four α-D-glucans were O-sulfonated to obtain derivatives (SL-II) having degrees of substitution (DS) from 0.9 to 2.1 respectively. The structure of the samples was analyzed by infrared spectra, elemental analysis, and 13C NMR. The weight-average molecular weight (Mw), radii of gyration (⟨s2z1⁄2) and intrinsic viscosity ([η]) of the native α-D-glucans and O-sulfonated derivatives were measured by size-exclusion chromatography combined with laser light scattering (SEC-LLS), LLS, and viscometry in 0.2 M aqueous NaCl and in dimethyl sulfoxide (DMSO) containing 0.25 M LiCl at 25 °C respectively. The Mw values of the O-sulfonated derivatives were much lower than those of the native α-D-glucans. The experimental results indicate that the O-sulfonated derivatives are water-soluble and exist as an expanded flexible chain in aqueous solution owing to intramolecular hydrogen bonding or interaction between charge groups. The in vivo and in vitro antitumor activities of the native α-D-glucans and their O-sulfonated derivatives against solid tumor Sarcoma 180 cells were evaluated and compared. Interestingly, all of the O-sulfonated derivatives exhibited higher antitumor activities than those of the native glucans. The results reveal that the effect of O-sulfonation of the α-D-glucan on the improvement of their antitumor activities was considerable.
    Download PDF (191K)
  • Kenji NARUSE, Seung Kwon YOO, Sun Myoung KIM, Yun Jaie CHOI, Hong Mie ...
    2006 Volume 70 Issue 1 Pages 93-98
    Published: 2006
    Released: January 23, 2006
    JOURNALS FREE ACCESS
    To investigate the ability of 1.8 kb or 3.1 kb bovine β-casein promoter sequences for the expression regulation of transgene in vivo, transgenic mice were produced with human type II collagen gene fused to 1.8 kb and 3.1 kb of bovine β-casein promoter by DNA microinjection. Five and three transgenic founder mice were produced using transgene constructs with 1.8 kb and 3.1 kb of bovine β-casein promoters respectively. Founder mice were outbred with the wild type to produce F1 and F2 progenies. Total RNAs were extracted from four tissues (mammary gland, liver, kidney, and muscle) of female F1 transgenic mice of each transgenic line following parturition. RT-PCR and Northern blot analysis revealed that the expression level of transgene was variable among the transgenic lines, but transgenic mice containing 1.8 kb of promoter sequences exhibited more leaky expression of transgene in other tissues compared to those with 3.1 kb promoter. Moreover, Western blot analysis of transgenic mouse milk showed that human type II collagen proteins secreted into the milk of lactating transgenic mice contained 1.8 kb and 3.1 kb of bovine β-casein promoter. These results suggest that promoter sequences of 3.1 kb bovine β-casein gene can be used for induction of mammary gland-specific expression of transgenes in transgenic animals.
    Download PDF (134K)
  • Sumiko OHASHI-KUNIHIRO, Hiroko HAGIWARA, Masafumi YOHDA, Haruhiko MASA ...
    2006 Volume 70 Issue 1 Pages 119-125
    Published: 2006
    Released: January 23, 2006
    JOURNALS FREE ACCESS
    A novel positive selection marker for Escherichia coli transformation was developed. The marker consisted of a DNA fragment encoding the C-terminal ribonuclease domain (CRD) of colicin E3 (colE3) and one or more amber stop codons between the initiation codon and the E3-CRD coding sequence. The toxicity of the marker was controlled by the suppressor activity the host cells possessed. This allowed both effective selection and propagation of the vector possessing the maker by selecting appropriate hosts from among those widely distributed: sup+ strains for selection and sup0 strains for propagation respectively. The insert DNA fragment was introduced onto the vector by replacing the marker DNA. The transformants harboring the vector with an insert grew, but those without an insert were effectively removed by the killing activity of E3-CRD encoded on the marker DNA. The marker was also successfully applied to λ phage display vector.
    Download PDF (115K)
  • Semra KOCABIYIK, Inci ÖZDEMIR
    2006 Volume 70 Issue 1 Pages 126-134
    Published: 2006
    Released: January 23, 2006
    JOURNALS FREE ACCESS
    An intracellular serine protease produced by Thermoplasma (Tp.) volcanium was purified using a combination of ammonium sulfate fractionation, ion exchange, and α-casein agarose affinity chromatography. This enzyme exhibited the highest activity and stability at pH 7.0, and at 50 °C. The purifed enzyme hydrolyzed synthetic peptides preferentially at the carboxy terminus of phenylalanine or leucine and was almost completely inhibited by PMSF, TPCK, and chymostatin, similarly to a chymotrypsin-like serine protease. Kinetic analysis of the Tp. volcanium protease reaction performed using N-succinyl-L-phenylalanine-p-nitroanilide as substrate revealed a Km value of 2.2 mM and a Vmax value of 0.045 μmol−1 ml−1 min−1. Peptide hydrolyzing activity was enhanced by >2-fold in the presence of Ca2+ and Mg2+ at 2–12 mM concentration. The serine protease is a monomer with a molecular weight of 42 kDa as estimated by sodium dodecyl sulfate–polyacrylamide gel electrophoresis and zymogram activity staining.
    Download PDF (196K)
  • Tadashi TAKAHASHI, Tsutomu MASUDA, Yasuji KOYAMA
    2006 Volume 70 Issue 1 Pages 135-143
    Published: 2006
    Released: January 23, 2006
    JOURNALS FREE ACCESS
    Ku genes play a key role in the non-homologous end-joining pathway. We have identified Ku70 and Ku80 homologs in the koji molds Aspergillus sojae and Aspergillus oryzae, and have constructed the disruption mutants of Ku70, Ku80, and Ku70–80 to characterize the phenotypic change in these mutants. Neither Ku70- nor Ku80-disrupted strains show hypersensitivity to the DNA damaging agents methylmethane sulfonate (MMS) and phleomycin. Moreover, undesirable phenotypes, such as poor growth or repressed conidiospore formation, were not observed in the Ku-disrupted A. sojae and A. oryzae.
    Download PDF (851K)
  • Kun-Hyung LEE, Shinichi NISHIMURA, Shigeki MATSUNAGA, Nobuhiro FUSETAN ...
    2006 Volume 70 Issue 1 Pages 161-171
    Published: 2006
    Released: January 23, 2006
    JOURNALS FREE ACCESS
    13-Deoxytedanolide is a structurally unique macrolide with strong antitumor activity isolated from a marine sponge. Recently, we showed that 13-deoxytedanolide bound to the large subunit of the yeast ribosome and inhibited polypeptide elongation in vitro, but the mechanism by which it exerts antitumor activity is still unknown. Here we show that 13-deoxytedanolide strongly induces plasminogen activator inhibitor 1 (PAI-1) promoter-derived gene expression. 13-Deoxytedanolide, unlike TGF-beta, did not cause apparent nuclear translocation of Smad2/3, but it relocalized the temperature-sensitive mutant of mouse p53 (p53Val153) from the cytoplasm to the nucleus at a nonpermissive temperature, suggesting that 13-deoxytedanolide inhibits protein synthesis. Indeed, the drug inhibited in vivo protein synthesis at low nanomolar concentrations and strongly activated stress-activated protein kinases such as p38 mitogen-activated protein kinase and Jun NH2-terminal protein kinase (JNK). Anisomycin, a well-known inducer of ribotoxic stress that activates both p38 and JNK, also activated PAI-1 gene expression, while other protein synthesis inhibitors that do not activate the kinases failed to do so. PAI-1 gene expression by 13-deoxytedanolide and anisomycin was blocked by SB202190, a specific inhibitor of p38, and SP600125, an inhibitor of both p38 and JNK. 13-Deoxytedanolide and anisomycin caused activation of apoptosis signal-regulating kinase 1, MKK3/MKK6, and SEK1/MKK4, the regulatory kinases upstream of p38 and JNK. These results suggest that 13-deoxytedanolide, like anisomycin, triggers a ribotoxic stress response that activates stress-activated protein kinase cascades, thereby inducing PAI-1 gene expression and apoptosis.
    Download PDF (254K)
  • Hiroaki KAJI, Akihiro TAI, Kazufumi MATSUSHITA, Hiroshi KANZAKI, Itaru ...
    2006 Volume 70 Issue 1 Pages 203-210
    Published: 2006
    Released: January 23, 2006
    JOURNALS FREE ACCESS
    In our previous study, water-soluble extracts from Bursaphelenchus xylophilus (B. xylophilus), a pine wood nematode, were shown to enhance interleukin (IL)-4 plus lipopolysaccharide-induced polyclonal immunoglobulin (Ig) E production in vitro in mice and to increase serum levels of an antigen-nonspecific IgE in vivo. Here we examined whether the nematode extracts stimulate immunofunctions of murine peritoneal macrophages. In both resident and inflammatory macrophages, Fcγ receptor-mediated phagocytosis was markedly activated by B. xylophilus extracts, while non-specific phagocytosis was not. The enhancement of specific phagocytosis was accompanied by an increase in the formation of IgG-Fcγ receptor rosettes. B. xylophilus extracts also stimulated IL-1β production in both types of macrophages, and enhanced NO production and mRNA expression of inflammatory cytokines in inflammatory macrophages. These results indicate that the extracts of B. xylophilus contain an activating substance(s) for immunofunctions in macrophages, besides an enhancing factor for polyclonal IgE production.
    Download PDF (138K)
  • Khondkar Ehteshamul KABIR, Hiroyuki SUGIMOTO, Hiroyuki TADO, Katsuhiko ...
    2006 Volume 70 Issue 1 Pages 219-229
    Published: 2006
    Released: January 23, 2006
    JOURNALS FREE ACCESS
    Bombyx mori chitinase (Bm-CHI), with a molecular mass of 75 kDa, was investigated on the possibility that it can serve as a biocontrol agent against the adult Japanese pine sawyer (JPS), Monochamus alternatus (Coleoptera: Cerambycidae). Oral ingestion of purified chitinase at concentrations of 3 μM (11.25 μg/50 μl) and 0.3 μM (1.125 μg/50 μl) caused high mortality in JPS, a significant decrease in bark consumption, and, only in high concentration, a slight reduction of body weight. Fluorescence assays indicated that peritrophic membrane (PM) chitin is degraded by the action of orally ingested Bm-CHI at 3 μM concentration only. Scanning electron micrographs clearly indicated that the beetles that ingested Bm-CHI of the same high concentration had their PM perforated and disrupted, but ultrastructural studies showed that the ingested chitinase did not affect the midgut epithelium. These findings open up the possibility of using insect chitinase as a biopesticidal enzyme. It should have agronomic potential for insect control.
    Download PDF (550K)
  • Akihiro SAITO, Hanae KAKU, Eiichi MINAMI, Takeshi FUJII, Akikazu ANDO, ...
    2006 Volume 70 Issue 1 Pages 237-242
    Published: 2006
    Released: January 23, 2006
    JOURNALS FREE ACCESS
    The ATP-binding cassette (ABC) transporter Ngc for N-acetylglucosamine (GlcNAc) of the chitin-degrader Streptomyces olivaceoviridis comprises the solute-binding protein NgcE, which has highest affinity for GlcNAc and N,N′-diacetylchitobiose {(GlcNAc)2} and reduced affinity for longer chitooligomers. NgcE was used to develop a generally applicable enzyme-linked immunosorbent assay (ELISA) system. As a prerequisite, the reducing end of (GlcNAc)2 was coupled with the ethylamino group of 2-(4-aminophenyl)ethylamine. The resulting conjugate was linked with amino groups of bovine serum albumin (BSA) to gain the neoglycoprotein BSA-APEA-(GlcNAc)2, which was fixed to wells in microtitre-plates. The NgcE protein was shown to bind efficiently to the immobilized BSA-APEA-(GlcNAc)2. In competition assays, the affinity of NgcE was 1,000-fold higher for GlcNAc and (GlcNAc)2 than for (GlcNAc)3 and (GlcNAc)4. These results are consistent with those previously obtained by surface plasmon resonance. Since the ELISA method can be performed very rapidly at low cost, it should be an efficient general tool to determine the affinity of a ligand to its cognate solute-binding protein.
    Download PDF (118K)
  • Nathan N. ARONSON, JR., Brian A. HALLORAN, Mikhail F. ALEXEYEV, Xiaoyi ...
    2006 Volume 70 Issue 1 Pages 243-251
    Published: 2006
    Released: January 23, 2006
    JOURNALS FREE ACCESS
    Family 18 chitinases have the signature peptide DGXDXDXE forming the fourth β-strand in the (β⁄α)8-barrel of their catalytic domain. The carboxyl-end glutamic acid, E315 in Serratia marcescens chitinase A, serves as the acid/base during chitin hydrolysis, and the side-chain of the preceding aspartic acid, D313, helps to position correctly the N-acetyl moiety of the glycosyl sugar undergoing hydrolysis. Chitin substrates are bound within a long cleft across the top of the barrel, whose floor consists of aromatic residues that hydrophobically stack with every other GlcNAc. Alanine substitution of the conserved Trp167 at the −3 subsite in Serratia marcescens chitinase A enhanced transglycosylation. Higher oligosaccharides were formed from both chitin tetra- and pentasaccharide, and the only hydrolytic product from chitin trisaccharide was the disaccharide. Greater retention of the glycosyl fragment at the active site of the −3 mutant of Serratia marcescens chitinase A might favor transglycosylation due to a stabilized conformation of its D313.
    Download PDF (188K)
  • Khondkar Ehteshamul KABIR, Daizo HIROWATARI, Katsuhiro WATANABE, Daizo ...
    2006 Volume 70 Issue 1 Pages 252-262
    Published: 2006
    Released: January 23, 2006
    JOURNALS FREE ACCESS
    75-kDa chitinase, which showed potential as a biocontrol agent against Japanese pine sawyer, was characterized after purification from the integument of the fifth instar larvae of Bombyx mori by chromatography on diethylaminoethyl (DEAE)-Toyoperal 650 (M), hydroxylapatite, and Fractogel EMD DEAE 650 (M) columns. The optimum pH was 6.0 toward N-acetylchitopentaose (GlcNAc5) and 10 toward glycolchitin. The optimum temperature was 60 °C toward GlcNAc5 and 25 °C toward glycolchitn. The enzyme was stable at pH 7–10 and below 40 °C. Kinetic analysis and reaction-pattern analysis using glycolchitin and N-acetylchitooligosacchraides as substrates indicated that 75-kDa chitinase is an endo- or random-type hydrolytic enzyme to produce the β anomeric product and that it prefers the longer N-acetylchitooligosaccharides, suggesting, together with the N-terminal amino acid sequence, that the 75-kDa chitinase belongs to family 18 of glycosyl hydrolases.
    Download PDF (218K)
Biochemistry & Molecular Biology Notes
Biochemistry & Molecular Biology Communications
Food & Nutrition Science Regular Papers
  • Dan JIN, Sung Hoon RYU, Hyun Won KIM, Eun Ju YANG, Soo Jung LIM, Yong ...
    2006 Volume 70 Issue 1 Pages 31-37
    Published: 2006
    Released: January 23, 2006
    JOURNALS FREE ACCESS
    Alkalin-reduced water (ARW) is known to exert several anti-cancer effects, as well as to scavenge reactive oxygen species (ROS) and reduce blood-glucose levels. This study was performed in order to determine the effects of ARW on the control of spontaneous diabetes in Otsuka Long-Evans Tokushima Fatty (OLETF) rats.
    We assigned 16 male OLETF rats (4 wk) to two groups: an experimental group, which was given ARW, and a control group, which received laboratory tap water. From week 6 to 32, the body weight, lipid composition, and glucose levels in the blood of the rats were measured. The glucose levels of both groups tended to increase. However, the ARW group’s glucose levels were significantly lower than those of the control group after 12 weeks (p<0.05). The total cholesterol and triglyceride levels in the ARW group were found to be significantly lower than those of the control group during the experimental period.
    These results suggest that ARW spurred the growth of OLETF rats during the growth stage, and that long-term ingestion of ARW resulted in a reduction in the levels of glucose, triglycerides, and total cholesterol in the blood.
    Download PDF (110K)
  • Mako NAKAYA, Hirofumi TACHIBANA, Koji YAMADA
    2006 Volume 70 Issue 1 Pages 47-53
    Published: 2006
    Released: January 23, 2006
    JOURNALS FREE ACCESS
    We examined the effect of 17β-estradiol (E2) on the cytokine production by mouse splenocytes. The production of interferon-γ (IFN-γ) was enhanced by E2 stimulation. E2 increased the number of cells expressing IFN-γ and the IFN-γ mRNA expression level in the cells. There were low- and high-level cells expressing IFN-γ in the population. The natural killer (NK) cells and NKT cells were the low-level cells expressing IFN-γ, and the number of these cells was increased by E2 stimulation. In addition, it was suggested that the enhancing effect of IFN-γ production by E2 was mediated through estrogen receptor (ER) α, and ERβ agonist stimulated IFN-γ production. ERs are expressed on plasma membrane as well as in nucleus. The ligand specific to plasma membrane-associated ER (mER) enhanced the IFN-γ production. In conclusion, our results indicated that E2 up-regulated the IFN-γ production by mediating ERα, ERβ and mERs.
    Download PDF (214K)
  • Masato OGINO, Rie TANAKA, Makoto HATTORI, Tadashi YOSHIDA, Yoshiko YOK ...
    2006 Volume 70 Issue 1 Pages 66-75
    Published: 2006
    Released: January 23, 2006
    JOURNALS FREE ACCESS
    Fatty-acylated sericin {1:0.7 molar ratio of sericin (Mr 18,700) to oleic acid} was prepared by lipase-catalyzed solid-phase synthesis in n-hexane containing oleic acid to endow sericin with interfacial properties. Acylation with oleic acid was confirmed by 1H-NMR. The fatty-acylated sericin exhibited superior emulsifying activity index and emulsion stability in the presence of 0–0.5 M NaCl, in a temperature range of 30–80 °C and pH range of 2–7, as compared with the control sericin. The fatty-acylated sericin (1:0.4 molar ratio) prepared by using low-molecular-weight sericin (Mr 5,000) also exhibited superior emulsifying properties. The affinity of the fatty-acylated sericin to a hydrophobic surface as evaluated by a biomolecular interaction analyzer was about twice as much as that of the control sericin. The fatty-acylated sericin showed retarded water vaporization, similar to the control sericin, indicating good retention of moistness, and was adsorbed four times as much to defatted wool with little desorption as compared with the control sericin.
    Download PDF (184K)
  • Azusa ITO, Makoto HATTORI, Tadashi YOSHIDA, Koji TAKAHASHI
    2006 Volume 70 Issue 1 Pages 76-85
    Published: 2006
    Released: January 23, 2006
    JOURNALS FREE ACCESS
    The effects of lysine (Lys), monosodium glutamate (GluNa), glycine, alanine and ε-poly(L-lysine) (PL) with different degrees of polymerization on the gelatinization behavior of potato starch granules were investigated by DSC, viscosity and swelling measurements, microscopic observation, and measurement of the retained amino acid amount to clarify the contribution of the net charge to their regulatory effects on the gelatinization behavior. The amino acids and PL each contributed to an increase in the gelatinization temperature, and a decrease in the peak viscosity and swelling. These effects strongly depended on the absolute value of their net charge. The disappearance of a negative or positive net charge by adjusting the pH value weakened the contribution. The swelling index and size of the potato starch granules changed according to replacement of the swelling medium. The amino acids and PL were easily retained by the swollen potato starch granules according to replacement of the outer solution of the starch granules.
    Download PDF (294K)
  • Yun Chun LIU, Yasushi HASEGAWA
    2006 Volume 70 Issue 1 Pages 86-92
    Published: 2006
    Released: January 23, 2006
    JOURNALS FREE ACCESS
    The lipolytic effect of powdered scallop shells was estimated in vitro and in vivo. The scallop shells consisted of 98% calcium carbonate and 2% organic compounds, the extracted organic components promoted lipolysis in 3T3-L1 adipocyte cells.
    Male Wistar rats were fed on an experimental diet containing either the scallop shell powder or calcium carbonate (control) for 28 d. Feeding the scallop shell powder resulted in a decrease in body weight and in the weight of white adipose tissue. While the organ weights of the liver, kidney, testis, pancreas, and spleen, and of the brown adipose tissue relative to the body weight were no different between the scallop shell powder diet and control diet, the white adipose tissue weight relative to the body weight significantly decreased in the rats fed on the scallop shell powder. The glycerol concentration in the serum increased in the rats fed on the scallop shell powder, suggesting that this promoted lipolysis in the adipose tissue. These results show that the organic components in the scallop shells induced the decrease in weight of the adipose tissue due to the promotion of lipolysis.
    Download PDF (548K)
  • Ho Jin HEO, Young-Min SUH, Mi-Jeong KIM, Soo-Jung CHOI, Nam Shik MUN, ...
    2006 Volume 70 Issue 1 Pages 107-111
    Published: 2006
    Released: January 23, 2006
    JOURNALS FREE ACCESS
    The choline acetyltransferase (ChAT) activator, which enhances cholinergic transmission via an augmentation of the enzymatic production of acetylcholine (ACh), is an important factor in the treatment of Alzheimer’s disease (AD). Methanolic extracts from Pueraria thunbergiana exhibited an activation effect (46%) on ChAT in vitro. Via the sequential isolation of Pueraria thunbergiana, the active component was ultimately identified as daidzein (4′,7-dihydroxy-isoflavone). In order to investigate the effects of daidzein from Pueraria thunbergiana on scopolamine-induced impairments of learning and memory, we conducted a series of in vivo tests. Administration of daidzein (4.5 mg/kg body weight) to mice was shown significantly to reverse scopolamine-induced amnesia, according to the results of a Y-maze test. Injections of scopolamine into mice resulted in impaired performance on Y-maze tests (a 37% decreases in alternation behavior). By way of contrast, mice treated with daidzein prior to the scopolamine injections were noticeably protected from this performance impairment (an approximately 12%–21% decrease in alternation behavior). These results indicate that daidzein might play a role in acetylcholine biosynthesis as a ChAT activator, and that it also ameliorates scopolamine-induced amnesia.
    Download PDF (80K)
  • Muneshige SHIMIZU, Soichi TANABE, Fumiki MORIMATSU, Koji NAGAO, Teruyo ...
    2006 Volume 70 Issue 1 Pages 112-118
    Published: 2006
    Released: January 23, 2006
    JOURNALS FREE ACCESS
    This study was performed to examine the effect of consumption of pork-liver protein hydrolysate (PLH) on body fat accumulation in Otsuka Long-Evans Tokushima Fatty (OLETF) rats as a non-insulin-dependent diabetes mellitus model and in Long-Evans Tokushima Otsuka (LETO) rats as a control. Male 20-week-old OLETF and LETO rats were pair-fed either PLH or casein containing diet for 14 weeks. In the OLETF rats, dietary PLH significantly reduced the growth and weight of fat pad including perirenal and epididymal adipose tissues. Consumption of PLH markedly suppressed hepatic activities of lipogenesis enzymes such as glucose-6-phosphate dehydrogenase and fatty acid synthase and slightly elevated fecal excretion of total fat. In the LETO rats, growth and adipose tissue weight were unaffected by dietary treatment. The results suggest that PLH is a novel ingredient suppressing body fat in genetically obese rats by reducing lipogenesis.
    Download PDF (107K)
  • Junko HIROSE, Yukio DOI, Naofumi KITABATAKE, Hiroshi NARITA
    2006 Volume 70 Issue 1 Pages 144-151
    Published: 2006
    Released: January 23, 2006
    JOURNALS FREE ACCESS
    We have recently established the monoclonal antibodies (mAbs) specific to the major food allergen, ovomucoid, as mAb 7D, recognizing the carbohydrate moiety of ovomucoid, and mAb 6H, the peptide moiety (Biosci. Biothechnol. Biochem., 68, 2490–2497, (2004)). Using these mAbs, we found commercially available ovalbumin preparations contaminated with a considerable amount of ovomucoid together with other glycoproteins. To examine the contaminants, egg white was subjected to cation-exchange chromatography. An unidentified protein was found in egg white that reacted with mAb 7D but not with mAb 6H, having a molecular size of about 52 kDa and a blocked N-terminus. Two internal amino acid sequences of the fragments obtained after a lysyl endopeptidase and a hydroxylamine treatment revealed the protein to be ovalbumin Y (ovalbumin-related gene Y protein). We conclude that ovalbumin Y is a unique chimeric glycoprotein having an amino acid sequence similar to that of ovalbumin, but having a carbohydrate moiety similar to that of ovomucoid.
    Download PDF (228K)
  • Miwako KUSUDA, Tsutomu HATANO, Takashi YOSHIDA
    2006 Volume 70 Issue 1 Pages 152-160
    Published: 2006
    Released: January 23, 2006
    JOURNALS FREE ACCESS
    The formation of water-soluble complexes from combinations of various polyphenols and bovine serum albumin (BSA) was analyzed by gel electrophoresis. Sodium dodecylsulfate (SDS) and native polyacrylamide gel electrophoretic (PAGE) analyses clearly showed complexes formed from BSA with oenothein B, corilagin, (+)-catechin, procyanidin B3, and gallic acid derivatives; however, it was difficult to distinguish between the complexes containing a single BSA molecule and the BSA molecule itself by using size-exclusion chromatography (SEC). Combining SDS and native PAGE analyses showed instability in the macromolecular complexes formed from pentagalloylglucose (PGG) and BSA. Research also revealed that the oxidation of (−)-epigallocatechin gallate (EGCG) contributed to the formation of more stable macromolecular complexes from EGCG and BSA.
    Download PDF (206K)
  • Makiko TAKENAKA, Kazuko NANAYAMA, Seiichiro ISOBE, Masatsune MURATA
    2006 Volume 70 Issue 1 Pages 172-177
    Published: 2006
    Released: January 23, 2006
    JOURNALS FREE ACCESS
    There was an obvious decrease in caffeic acid derivatives during the boiling of cube-shaped blocks of sweet potatoes. They also decreased in a mixture of freeze-dried sweet-potato powder and water maintained at room temperature. Ascorbic acid prevented the decrease, supporting the occurrence of an enzyme reaction with polyphenol oxidase (PPO). 5-O-Caffeoylquinic acid (5-CQA, “3-O-caffeoylquinic acid” as a trivial name) and 3,5-di-O-caffeoylquinic acid (3,5-CQA), major phenolic compounds of sweet potato, did not change when they were separately heated in boiling water. When the mixture of powdered sweet potato and water was heated at 100 °C, there was only a negligible decrease in the total amount of phenolic compounds, and portions of 5-CQA and 3,5-CQA were found to be isomerized to 3-CQA, 4-CQA, 3,4-CQA, and 4,5-CQA. The content and composition of the phenolic compounds in sweet potatoes differed between fresh and long-stored ones, as did their response to heating.
    Download PDF (130K)
  • Jun NISHIDA, Jun KAWABATA
    2006 Volume 70 Issue 1 Pages 193-202
    Published: 2006
    Released: January 23, 2006
    JOURNALS FREE ACCESS
    The DPPH radical scavenging activity of 2′,4′,6′-trihydroxy- and 2′-hydroxy-4′,6′-dimethoxychalcones carrying a 2,3- and 3,4-dihydroxylated, and 3,4,5-trihydroxylated B-ring was evaluated in alcoholic and non-alcoholic solvents. All test compounds scavenged more than two equivalent of radicals by a possible conversion to the corresponding B-ring quinones and in most cases subsequently underwent cyclization to aurones and flavanones, these being identified in the reaction solutions by an in situ NMR analysis. Interestingly, the reaction between 2′,3,4-trihydroxy-4′,6′-dimethoxychalcone and the DPPH radical was significantly affected by the solvent used, which might be accounted for by the difference in readiness for cyclization to an aurone.
    Download PDF (159K)
Food & Nutrition Science Notes
Microbiology & Fermentation Technology Regular Papers
  • Ken-ichi HASHIMOTO, Hisashi KAWASAKI, Kouki AKAZAWA, Jun NAKAMURA, You ...
    2006 Volume 70 Issue 1 Pages 22-30
    Published: 2006
    Released: January 23, 2006
    JOURNALS FREE ACCESS
    Overproduction of glutamate by Corynebacterium glutamicum is induced by biotin limitation or by the supplementation of specific detergents, sublethal amounts of penicillin, or cerulenin. But, it remains unclear why these different treatments, which have different sites of primary action, produce similar effects.
    In this study, it was found that the cellular content of mycolic acids—characteristic constituents of Corynebacterineae that are synthesized from fatty acids and form a cell surface layer—decreased under all conditions that induced glutamate overproduction. Furthermore, short mycolic acids increased under conditions of biotin limitation and cerulenin supplementation. These results suggest that different treatments produce the same effect that causes defects in the mycolic acid layer. This is perhaps one of the key factors in overproduction of glutamate by C. glutamicum.
    Download PDF (143K)
  • Hisashi KAWASAKI, Koutaro KOYAMA, Sachio KUROKAWA, Kunihiko WATANABE, ...
    2006 Volume 70 Issue 1 Pages 99-106
    Published: 2006
    Released: January 23, 2006
    JOURNALS FREE ACCESS
    (R)-3-Amino-3-phenylpropionic acid ((R)-β-Phe) and (S)-3-amino-3-phenylpropionic acid ((S)-β-Phe) are key compounds on account of their use as intermediates in synthesizing pharmaceuticals. Enantiomerically pure non-natural amino acids are generally prepared by enzymatic resolution of the racemic N-acetyl form, but despite the intense efforts this method could not be used for preparing enantiomerically pure β-Phe, because the effective enzyme had not been found. Therefore, screening for microorganisms capable of amidohydrolyzing (R,S)-N-acetyl-3-amino-3-phenylpropionic acid ((R,S)-N-Ac-β-Phe) in an enantiomer-specific manner was performed.
    A microorganism having (R)-enantiomer-specific amidohydrolyzing activity and another having both (R)-enantiomer- and (S)-enantiomer-specific amidohydrolyzing activities were obtained from soil samples. Using 16S rDNA analysis, the former organism was identified as Variovorax sp., and the latter as Burkholderia sp. Using these organisms, enantiomerically pure (R)-β-Phe (>99.5% ee) and (S)-β-Phe (>99.5% ee) with a high molar conversion yield (67%–96%) were obtained from the racemic substrate.
    Download PDF (191K)
  • Hideaki NAKAJIMA, Yuichi HONGOH, Satoko NODA, Yasuhiko YOSHIDA, Ron US ...
    2006 Volume 70 Issue 1 Pages 211-218
    Published: 2006
    Released: January 23, 2006
    JOURNALS FREE ACCESS
    The microbial community adherent directly or indirectly to the gut wall of termites is distinct from that of the other habitats in the gut. The bacterial 16S rRNA genes were identified from the fractionated gut walls of two termite species, Hodotermopsis sjoestedti and Neotermes koshunensis, and compared with those previously identified from Reticulitermes speratus. Surprisingly, the bacterial constituents were almost entirely different among the termites at the phylotype level (the criterion of the phylotype was >97% nucleotide identity). Bacteria in the order Bacteroidales, which were commonly abundant symbionts on gut walls, were phylogenetically analyzed. They were dispersed in a number of clusters formed by phylotypes from the guts of various termites. In situ hybridization with probes specific for some phylotypes and a phylogenetic cluster detected the cells of several Bacteroidales members with a significant variety of cell morphology in the gut wall fractions, which reflects the phylogenetic diversity of this order.
    Download PDF (268K)
feedback
Top