Curriculum Vitaes

TANAMOTO KEN'ICHI

  (棚元 憲一)

Profile Information

Affiliation
Faculty of Pharmacy, Department of Pharmaceutical Sciences, Musashino University
Degree
学士(東京大学)
博士(東京大学)

J-GLOBAL ID
200901064998242955
researchmap Member ID
0000041232

Committee Memberships

 7

Awards

 1

Papers

 11
  • Kei-ichi Sugiyama, Masashi Muroi, Mawo Kinoshita, Osamu Hamada, Yuji Minai, Yoshiko Sugita-Konishi, Yoichi Kamata, Ken-ichi Tanamoto
    JOURNAL OF TOXICOLOGICAL SCIENCES, 41(2) 273-279, Apr, 2016  Peer-reviewed
    Macrophages induce the innate immunity by recognizing pathogens through Toll-like receptors (TLRs), which sense pathogen-associated molecular patterns. Myeloid differentiation factor 88 (MyD88), which is an essential adaptor molecule for most TLRs, mediates the induction of inflammatory cytokines through nuclear factor kappa B (NF-kappa B). Trichothecene mycotoxin deoxynivalenol (DON) shows immunotoxic effects by interrupting inflammatory mediators produced by activated macrophages. The present study investigates the effect of DON on NF-kappa B in activated macrophages through MyD88-dependent pathways. DON inhibited NF-kappa B-dependent reporter activity induced by MyD88-dependent TLR agonists. In addition, lipopolysaccharide-induced phosphorylation of interleukin-1 receptor-associated kinase 1 and inhibitor kappa B alpha were attenuated by DON. Furthermore, DON downregulated the expression level of MyD88. These results suggest that DON inhibits NF-kappa B activation in macrophages stimulated with TLR ligands via MyD88-dependent TLR signals. Therefore exposure to DON may lead to the inhibition of MyD88-dependent pathway of TLR signaling
  • Masashi Muroi, Ken-ichi Tanamoto
    TOXICOLOGY LETTERS, 235(3) 199-205, Jun, 2015  Peer-reviewed
    The NLRP3 inflammasome, composed of caspase-1, NLRP3 and ASC, plays a critical role in the clearance of microbial pathogens. Here, we found that the treatment of mouse macrophages with the zinc-containing dithiocarbamate ziram, a widely used fungicide in agriculture, caused a decrease in pro-caspase-1 and NLRP3 levels while not affecting ASC level. Ziram did not affect levels of pro-caspase-1 and NLRP3 mRNA, and no cleavage products of pro-caspase-1 including p10 subunit, which is an autocleavage product of pro-caspase-1, were detected, indicating that the decrease was associated with degradation of these proteins. The decrease was inhibited by SH-type antioxidants, N-acetyl cysteine, dithiothreitol and 2-mercaptoethanol, or a metal chelator EDTA but not by inhibitors of proteasome, lysosomes, autophagy and matrix metalloproteases. Thiram, a comparator for ziram that does not contain zinc, showed a weaker decrease in protein levels. Furthermore, the zinc-containing dithiocarbamate, zinc diethyldithiocarbamate, efficiently decreased the levels of pro-caspase-1 and NLRP3, whereas dithiocarbamates, dimethyldithiocarbamate and diethyldithiocarbamate without zinc, were less active. The organic zinc compound [3,4-toluenedithiolato(2-)] zinc hydrate did not induce a decrease in protein levels. Ziram also inhibited IL-1 beta production by macrophages in response to lipopolysaccharide and bacterial clearance during Salmonella infection of macrophage cells. These results indicate that ziram causes degradation of pro-caspase-1 and NLRP3 in a zinc-and oxidative property-dependent manner and suggest that exposure to ziram may compromise the clearance of microbial pathogens. (C) 2015 Elsevier Ireland Ltd. All rights reserved.
  • Takaaki Kitajima, Masashi Muroi, Naomi Yamashita, Ken-ichi Tanamoto
    BIOLOGICAL & PHARMACEUTICAL BULLETIN, 37(1) 74-80, Jan, 2014  Peer-reviewed
    Body and excrement extracts from Dermatophagoides Prime were used to study stimulation of Toll-like receptors (TLRs). The excrement extract stimulated nuclear factor (NF)-kappa B-dependent reporter activity to an extent similar to lipopolysaccharide (LPS) in a mouse macrophage cell line, J774A.1, but the activity of the body extract was negligible. The excrement extract also activated NF-kappa B in HEK293 cells expressing TLR1/TLR2, TLR2/TLR6 and CD14/TLR4/MD-2, whereas no activation was observed in cells expressing TLR3, TLR5, TLR7, TLR8 or TLR9. Although the excrement extract required co-expression of CD14, TLR4 and MD-2 in HEK293 cells to activate NF-kappa B, efficient activation was still observed in I-13.35 cells, a bone-marrow macrophage cell line established from LPS-hypo-responsive C3H/HeJ mice. The excrement extract activated NF-kappa B in HEK293 cells expressing TLR2 alone, but the activation was significantly increased by co-expression of CD14. Polymyxin B inhibited CD14/TLR4/MD-2- and CD14/TLR2-mediated activation of NF-kappa B but not the activation in I-13.35 cells. These results indicate that CD14/TLR4/MD-2-dependent and CD14/TLR2-dependent mechanisms are involved in the activation of NF-kappa B by the excrement extract of D. farinae and suggest that the extract also contains substances that activate NF-kappa B through non-TLR-mediated mechanisms.
  • Naina Shah, Montserrat Montes de Oca, Maria Jover-Cobos, Ken-ichi Tanamoto, Masashi Muroi, Kei-ichi Sugiyama, Nathan A. Davies, Rajeshwar P. Mookerjee, Dipok Kumar Dhar, Rajiv Jalan
    LIVER TRANSPLANTATION, 19(7) 751-761, Jul, 2013  Peer-reviewed
    Strategies for the prevention of multiorgan dysfunction (MOD) in acetaminophen (APAP)-induced acute liver failure (ALF) are an unmet need. Our study tested the hypothesis that sterile inflammation induced by APAP in a mouse model would activate toll-like receptor 4 (TLR4) in the liver and extrahepatic organs and lead to the progression of ALF and MOD and that the administration of the novel TLR4 antagonist STM28 (a peptide formed of 17 amino-acids) would prevent liver injury and associated MOD. ALF and, subsequently, MOD were induced in TLR4-knockout (KO) mice (B6.B10ScN-Tlr4 (lpsdel) /JthJ) and wild-type (WT) mice (C57BL/6) with APAP (500 mg/kg). A second set of experiments was conducted to evaluate the effects of a pretreatment with a novel TLR4 antagonist, STM28, on APAP-induced MOD in CD1 mice. Animals were sacrificed at the coma stage, and plasma, peripheral blood cells, liver, kidneys, and brain were collected. Biochemistry values and cytokines were measured. Liver and kidneys were studied histologically and were stained for TLR4 and activated Kupffer cells, and the expression of nuclear factor kappa B-p65 was quantified with western blotting. Brain water was measured in the frontal cortex. After APAP administration, TLR4-KO (NFkBp65) mice were relatively protected from liver necrosis and end-organ dysfunction and had significantly better survival than WT controls (P < 0.01). STM28 attenuated liver injury and necrosis, reduced creatinine levels, and delayed the time to a coma significantly. The increases in cytokines in the plasma and liver, including TLR4 expression and the activation of Kupffer cells, after APAP administration were reduced significantly in the STM28-treated animals. The increased number of circulating myeloid cells was reduced significantly after STM28 treatment. In conclusion, these data provide evidence for an important role of the TLR4 antagonist in the prevention of the progression of APAP-induced ALF and MOD. Liver Transpl 19:751-761, 2013. (C) 2013 AASLD.
  • Norihiko Ogura, Masashi Muroi, Yuka Sugiura, Ken-ichi Tanamoto
    PATHOGENS AND DISEASE, 67(3) 199-205, Apr, 2013  Peer-reviewed
    We investigated the difference in the effect of synthetic lipid A compounds on MyD88-dependent and -independent Toll-like receptor 4 (TLR4) signaling in mouse macrophage cells. At higher concentrations, Escherichia coli-type hexa-acylated lipid A 506, Salmonella-type hepta-acylated lipid A 516, the lipid A precursor lipid IVa and monophosphoryl lipid A induced similar levels of production of the MyD88-dependent cytokine IL-1 beta although their potencies varied, whereas the maximum production of the MyD88-independent cytokine RANTES induced by lipid IVa was less than 50% that of other lipid A compounds. A maximum level of NF-kappa B activation, which is involved in IL-1 beta gene transcription, was also induced to a similar level by these four lipid A compounds, while the maximum level of IFN-beta promoter activity induced during MyD88-independent signaling was also less than 50% for lipid IVa stimulation compared with other lipid A compounds. Early I kappa B alpha phosphorylation activated by MyD88-dependent signaling was similarly induced by 506 and lipid IVa, whereas lipid IVa barely stimulated the phosphorylation of IRF3, a MyD88-independent transcription factor, although efficient phosphorylation was observed with 506 stimulation. These results indicate that lipid IVa has limited activity toward MyD88-independent signaling of TLR4, in macrophage cell lines, despite having efficient activity in the MyD88-dependent pathway.

Misc.

 172
  • Akiyama T, Yamazaki T
    Shokuhin Eiseigaku Zasshi., 52(1) 40-46, 2011  Peer-reviewed
  • Takahiro Ohnishi, Masashi Muroi, Ken-ichi Tanamoto
    MICROBIOLOGY AND IMMUNOLOGY, 54(2) 74-80, Feb, 2010  
    The effects of the soluble forms of the endotoxin receptor molecules sMD-2 and sCD14 on bacterial growth were studied. When Escherichia coli and Bacillus subtilis were incubated at 37 degrees C for 18 hr with either sMD-2 or sCD14, growth of these bacteria was significantly inhibited as evaluated by viable cell counts and NADPH/NADH activity. A mutant of sCD14 (sCD14d57-64) lacking a region essential for LPS binding did not inhibit the growth of E. coli, whereas this mutant did inhibit the growth of B. subtilis. Addition of excess PG to the bacterial culture reversed the inhibitory effect of sMD-2 on the growth of B. subtilis, but not on the growth of E. coli. Furthermore, when evaluated by ELISA, both sMD-2 and sCD14 bound specifically to PG. Taken together, these results indicate that sMD-2 and sCD14 inhibit the growth of both Gram-positive and Gram-negative bacteria and further suggest that binding to PG and LPS is involved in the inhibitory effect of sMD-2 on Gram-positive bacteria and of sCD14 on Gram-negative bacteria, respectively.
  • Kei-ichi Sugiyama, Masashi Muroi, Ken-ichi Tanamoto, Motohiro Nishijima, Yoshiko Sugita-Konishi
    TOXICOLOGY LETTERS, 192(2) 150-154, Feb, 2010  
    Deoxynivalenol (DON) and nivalenol (NIV), trichothecene mycotoxins, are secondary metabolites produced by Fusarium fungi. Trichothecene mycotoxins cause immune dysfunction, thus leading to diverse responses to infection. The present study evaluated the effect of DON and NIV on nitric oxide (NO) production by RAW264 cells stimulated with lipopolysaccharide (LPS). LPS-induced NO production was reduced in the presence of these toxins. The transcriptional activation and expression of inducible NO synthase (iNOS) by LPS were also repressed by these toxins. DON or NIV inhibited LPS-induced expression of interferon-beta (IFN-beta), which plays an indispensable role in LPS-induced iNOS expression. These results indicate that DON and NIV inhibit the LPS-induced NO and IFN-beta production, which both play an important role for host protection against invading pathogens, and suggests that the inhibition of these factors may be involved in the immunotoxic effects of these mycotoxins. (C) 2009 Elsevier Ireland Ltd. All rights reserved.
  • Yoshida T, Yoshioka Y, Fujimura M, Kayamuro H, Yamashita K, Higashisaka K, Nakanishi R, Morishita Y, Nabeshi H, Yamashita T, Muroi M, Tanamoto K, Nagano K, Abe Y, Kamada H, Kawai Y, Mayumi T, Itoh N, Yoshikawa T, Tsunoda S, Tsutsumi Y
    Biol.Pharm.Bull., 33(5) 780-783, 2010  
  • Akiyama Takumi, Sasaki Ryo, Yamazaki Takeshi, Tanamoto Kenichi, Yamagata Kazuo, Kawamura Yoko
    Japanese Journal of Food Chemistry and Safety, 17(2) 88-95-95, 2010  
    Food manufacturing enzymes are named according to enzyme functions in Japan. Active enzyme proteins are not identified as substances. Therefore, in the List of Existing Food Additives, most items consist of enzymes from different origins. If a chemical analysis of proteins in enzyme products can identify origins, the method will be a probable candidate for a simple identification test for enzyme origins. SDS-PAGE was applied to α-amylases, β-amylases, catalases, β-galactosidases, glucoamylases, cellulases, proteases, and hemicellulases. As many products as possible were collected to cover most of currently circulating products in Japan. One hundred and three products available in Japan were analyzed by SDS-PAGE. Molecular weights of major proteins were calculated. Characteristic electrophoresis patterns were found in most products. Useful information on relationships between origins and separation patterns of proteins was obtained. Identification of species was achieved for all products from plants and many products from bacteria or fungi although identification was limited to the genera level for some microorganisms like Bacillus.
  • Akiyama T, Hayashi A, Yamazaki T, Tada A, Sugimoto N, Yun YS, Kunugi A, Kawamura Y
    J. Food. Hyg. Soc. Japan, 51 264-272, 2010  
  • Toshikazu Shioiri, Masashi Muroi, Fumihiko Hatao, Masato Nishida, Toshihisa Ogawa, Yoshikazu Mimura, Yasuyuki Seto, Michio Kaminishi, Ken-ichi Tanamoto
    BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR BASIS OF DISEASE, 1792(10) 1011-1018, Oct, 2009  
    Endothelial cell injury/dysfunction is considered to play a critical role in the pathogenesis of severe sepsis and septic shock. Although it is considered that endothelial cell apoptosis is involved in endothelial injury/dysfunction. physiological involvement remains ambiguous since the induction of apoptosis requires the inhibition of endogenous apoptosis inhibitors. Here we show that caspase-3 activation, a biological indicator of apoptosis, is observed in response to lipopolysaccharide (LPS) Stimulation even under the influence of endogenous apoptosis inhibitors, and that activated caspase-3 is rapidly released from human umbilical vein endothelial cells (HUVEC) In the presence of cycloheximide (CHX), an increase in intracellular caspase-3/7 activity in response to LIPS was not detected in HUVEC up to 24 h following Stimulation even in the presence of LPS-binding protein (LBP). soluble CD14 and soluble MD-2, whereas the decrease in cell viability and increase in release of the cellular enzyme lactate dehydrogenase (LDH) were observed in a soluble CD14/LBP-dependent manner On the other hand, even in the absence of CHX, a significant increase in caspase-3/7 activity and a cleaved caspase-3 fragment with a slight increase in LDH release was observed in culture supernatants in response to LIPS This increase in caspase-3/7 activity was observed even when LDH release was undetected. These results indicate that caspase-3 is activated by LIPS under physiological conditions and suggest that HUVEC escape from cell death by rapidly releasing activated caspase-3 into extracellular space. Failure of this escape mechanism may result in endothelial injury/dysfunction (C) 2009 Elsevier B V. All rights reserved
  • Yusai Ito, Naoki Sugimoto, Takumi Akiyama, Takeshi Yamazaki, Kenichi Tanamoto
    TETRAHEDRON LETTERS, 50(28) 4084-4086, Jul, 2009  
    Cepaic acid was isolated as a novel xanthylium yellow pigment from the dried outer scales of the yellow onion Allium cepa Linne. Its structure was elucidated on the basis of ESI-MS and 2D NMR spectroscopy as a 9-carboxy-1,3,6,8-tetrahydroxyxanthylium, which suggests that cepaic acid and other yellow pigments in the dried outer skin of onion were formed by the nucleophilic reaction of phloroglucinol derived from quercetin, a flavonol in onion scales, by autoxidation to glyoxylic acid. To our knowledge, this is the first report of such a pigment in yellow onion. (C) 2009 Elsevier Ltd. All rights reserved.
  • Tada Atsuko, Sugimoto Naoki, Furusho Noriko, Ishizuki Kyoko, Sato Kyoko, Yamazaki Takeshi, Tanamoto Kenichi
    Japanese Journal of Food Chemistry and Safety, 16(2) 92-96-96, 2009  
    Ozokerite, a natural gum base used as a food additive, is described as a purified wax substance found in veins of wax shale and is composed mainly of C29-C53 hydrocarbons, in the Notice (1996) relating to existing food additives in Japan. In order to evaluate the quality of commercially available ozokerite, we have analyzed the constituents. GC/MS analysis of ozokerite showed that the main components were saturated C22-C38 hydrocarbons, while the minor components were saturated C39-C58 hydrocarbons. The range of carbon numbers observed in the main saturated hydrocarbons was lower than those referred to in the Notice. The total concentration of the main saturated C22-C38 hydrocarbons was found, by GC/FID analysis, to be 81%.
  • 室井正志, 棚元 憲一
    エンドトキシン研究, 11 69-71, 2009  
  • 田原麻衣子, 杉本直樹, 末松孝子, 有福和紀, 斎藤剛, 井原俊英, 吉田雄一, 多田敦子, 久保田領志, 清水久美子, 山崎壮, 中澤裕之, 西村哲治
    日本食品化学学会誌, 16 28-33, 2009  
  • 大西貴弘, 室井正志, 棚元 憲一
    エンドトキシン研究, 11 72-74, 2009  
  • 室井正志, 棚元 憲一
    エンドトキシン研究, 11 17-19, 2009  
    MyD88およびIRAK-1により誘導されるNF-<SUB>k</SUB>Bの活性化にどのような機序でTRAF6が関与するのかを解説した。
  • Kawamura Y, Mutsuga M, Yamauchi T, Ueda S, Tanamoto K
    J. Food. Hyg. Soc. Japan, 50 93-96, 2009  
  • 杉山圭一, 室井正志, 棚元 憲一, 小西良子
    エンドトキシン研究, 11 81-83, 2009  
  • Tada A, Sugimoto N, Sato K, Akiyama T, Asanoma M, Yun YS, Yamazaki T, Tanamoto K
    Shokuhin Eiseigaku Zasshi., 50 160-166, 2009  
  • Tatebe C, Kawasaki H, Kubota H, Sato K, Tanamoto K, Kawamura Y
    Japn.J.Food Chem.Safety(JJFCS), 16(2) 78-83-83, 2009  
    Headspace gas chromatography (HS-GC) is an accepted method for analysis of residual solvents in pharmaceuticals, food additives and food. The amounts of residual solvent present in various food thickeners were analysed by HS-GC standard addition method. Conditions for the HS-GC were optimised, and equilibration time was determined to be 40min at 60℃ for the determination of residual solvent. The results were very similar to those obtained by distillation and gas chromatography (Distillation-GC). We conclude that both methods are equally efficient for the determination of residual solvent in thickeners. In addition capillary column (Aquatic-2 GL Sciences Co.) was used to analyze by headspace or distillation.
  • Mutsuga M, Lee YK, Kawamura Y, Tanamoto K
    Shokuhin Eiseigaku Zasshi., 50 160-166, 2009  
  • Kawasaki H, Furusho N, Tatebe C, Kubota H, Yanagi T, Yasukouchi Y, Mori Y, Yamashita Y, Iizuka T, Takahata K, Takahashi J, Sato K, Tanamoto K
    Japn.J.Food Chem.Safety(JJFCS), 16 78-83, 2009  
  • Kei-ichi Sugiyama, Masashi Muroi, Ken-ichi Tanamoto
    EUROPEAN JOURNAL OF PHARMACOLOGY, 594(1-3) 152-156, Oct, 2008  
    Lipopolysaccharide (LPS) is a component of the outer membrane of Gram-negative bacteria. It is a ligand for Toll-like receptor 4 (TLR4), which plays an essential role in innate immunity. Macrophages and dendritic cells exposed to LPS overproduce proinflammatory mediators, leading to septic shock. In this study, we screened for peptides that associate with TLR4 with a yeast two-hybrid screen using the human TLR4 extracellular domain as bait. A peptide (STM28) isolated from the screen inhibited LPS-induced nuclear factor-kappa B (NF-kappa B) activation in human and mouse macrophage cells and interacted with TLR4 in yeast and mammalian cells. STM28 showed no inhibitory effects against NF-kappa B activation induced by TLR1/2, TLR3 and TLR9 ligands in a mouse macrophage cell line, RAW 264. In addition, STM28 suppressed LPS-induced tumor necrosis factor-a production by differentiated THP-1 cells. Moreover LPS-induced lethality in D-galactosamine-sensitized mice was significantly repressed by STM28 in a dose-dependent manner. These results demonstrate that STM28 selectivity inhibits TLR4-induced macrophage activation, and suggest that STM28 may have utility as a novel therapeutic agent for Gram-negative bacterial sepsis. (C) 2008 Elsevier B.V. All rights reserved.
  • Fumihiko Hatao, Maya Yamamoto, Masashi Muroi, Michio Kaminishi, Ken-ichi Tanamoto
    FEMS IMMUNOLOGY AND MEDICAL MICROBIOLOGY, 53(2) 260-264, Jul, 2008  
    IRAK-4 plays an essential role in Toll-like receptor (TLR)/IL-1 receptor signaling. However, its signaling and regulation mechanisms have remained elusive. We have reported previously that stimulation of TLR2, TLR4 or TLR9, but not TLR3, leads to downregulation of IRAK-4 protein. Here, we show that expression of MyD88 leads to downregulation of endogenous as well as exogenously expressed IRAK-4 protein in HEK293 cells. Expression of TRIF did not cause IRAK-4 downregulation although it induced NF-kappa B activation. Expression of either a deletion mutant of MyD88 lacking its death domain or MyD88s, neither of which induced NF-kappa B activation, did not lead to IRAK-4 downregulation. MyD88-induced downregulation was observed in an IRAK-4 mutant lacking the kinase domain, but not in another mutant lacking the death domain. These results demonstrate that downregulation of IRAK-4 requires activation of the MyD88-dependent pathway and that the death domains of both MyD88 and IRAK-4 are important for this downregulation.
  • Yutaka Kikuchi, Tomoshi Kakeya, Osamu Nakajima, Ayako Sakai, Kikuko Ikeda, Naoto Yamaguchi, Takeshi Yamazaki, Ken-ichi Tanamoto, Haruo Matsuda, Jun-ichi Sawada, Kosuke Takatori
    FEBS JOURNAL, 275(11) 2965-2976, Jun, 2008  
    The human prion protein (PrP) is a glycoprotein with a glycosylphosphatidylinositol (GPI) anchor at its C-terminus. Here we report alternative splicing within exon 2 of the PrP gene (PRNP) in the human glioblastoma cell line T98G. The open reading frame of the alternatively spliced mRNA lacked the GPI anchor signal sequence and encoded a 230 amino acid polypeptide. Its product, GPI-anchorless PrP (GPI(-) PrPSV), was unglycosylated and soluble in non-ionic detergent, and was found in the cytosolic fraction. We also detected low levels of alternatively spliced mRNA in human brain and non-neuronal tissues. When long-term passaged T98G cells were placed in a low-oxygen environment, alternatively spliced mRNA expression increased and expression of normally spliced PrP mRNA decreased. These findings imply that oxygen tension regulates GPI(-) PrPSV expression in T98G cells.
  • Mutsuga Motoh, Yamaguchi Miku, Kawamura Yoko, Tanamoto Kenichi
    Japanese Journal of Food Chemistry and Safety, 15(2) 67-72-72, 2008  
    In Europe, semicarbazide (SEM) was detected from bottled baby foods. SEM is a thermal degradation product of azodicarbonamide which is a foaming agent for plastic gaskets on metal lids. In this paper, a determination method of SEM by the incremental standard addition technique was established. And SEM in 64 of bottled foods marketed in Japan were surveyed. In the bottled baby food, SEM was detected 5.7-46.7 μg/g in 9 samples, and not detected in 2 samples. This contamination level is almost the same as that of the investigation in EU. In the general bottled food, SEM was detected 0.6-45.2 μg/g in 23 samples, and not detected in 30 samples. This level was slightly higher compared with that of EU. In all the bottled foods containing SEM, SEM or hydrazodicarbonamide was detected also from their sealing gasket. These results indicate that SEM detected from bottled food is degradation product of ADC added to the sealing gasket.
  • 室井正志, 中川恭好, 島圭介, 市村克彦
    医薬品研究, 39 309-312, 2008  
  • Kawasaki Hiromi, Tatebe Chie, Takagi Shigeyuki, Kawasaki Yuki, Hara Takahiko, Iizuka Tayoshi, Sugimoto Naoki, Sato Kyoko, Tanamoto Kenichi
    Japanese Journal of Food Chemistry and Safety, 15(3) 122-128-128, 2008  
    In order to set official analytical method in foods, the method of determining polysorbates(PSs) with rapid screening test by TLC and colorimetric assay were developed. PSs were extracted from processed foods with acetonitrile containing methanol. The extract was cleaned up on an alumina column (aluminum oxide, basic, 10g) and a silica gel cartridge (Sep-Pak Plus Silica, 690mg) to remove food color and other interfering substance. Suitable conditions of TLC to determine PS were as follow: adsorbent, silica gel ; developing solvent, dichloromethane -methanol -acetone -water (100 : 20 : 15 : 3) mixture; color development, Dragendorff reagent. The content of PS was obtained by colorimetric assay - cobalt thiocyanate method with PS80 as a standard substance. The recoveries of PS80 from eleven kinds of foods fortified at the level of 0.1 g/kg were 48.8-76.2% except 24.6% for a freezed dry food. The proposed method was applied to cocoa mix containg PS60. PS was confirmed at 0.26g/kg as PS80.
  • Muroi M, Tanamoto K
    J.Leukocyte. Biol., 5 702-707, 2008  
  • 杉山圭一, 室井正志, 棚元 憲一
    エンドトキシン研究, 11 20-22, 2008  
  • Sugimoto N, Tada A, Kuroyanagi M, Yoneda Y, Yun YS, Kunugi A, Sato K, Yamazaki T
    Shokuhin Eiseigaku Zasshi, 49 56-62, 2008  
  • 室井正志
    エンドトキシン研究, 11 17-19, 2008  
  • Mutsuga M, Kawamura Y, Tanamoto K
    Food Addit Contam., 27 1-8, 2008  
  • Tatebe Chiye, Kawasaki Hiromi, Sugimoto Naoki, Sato Kyoko, Tanamoto Ken-ichi
    Japanese Journal of Food Chemistry and Safety, 15(3) 129-134-134, 2008  
    In our previous study, we reported a rapid screening test method of polysorbates (PSs) using TLC. Although the method is useful in terms of obtaining characteristic spot pattern of PSs, it is impossible to discriminate each polysorbate (PS20, 40, 60, 80, 65 or 85) and to identify the molecular species in PSs. Thus we developed a new qualitative analytical method of PSs using LC/MS. PSs were separated on a YMC pack C8 column (150 mm × 2.0 mm I.D., 5 μm, 30 nm) by a gradient elution with a mixture of water-methanol containing 0.1% formic acid. PSs were analyzed in selected ion monitoring (SIM) mode, with Na+ adducts produced by electrospray ionization. Selected ion was calculated from the molecule consisting of Na+ adducts of 20 oxyethylene (EO) sorbitan (So) mono-, di-, or tri-ester of fatty acids (FA) (So-EO(20)-FA(1〜3)), respectively. the SIM peak of each PS was eluted at different retention time by constituent FA and esterification degree of PS and the PS with different length of EO (12〜35) was found in each SIM peak. Using the method we tried to identify the molecular species in the spots obtained by TLC analysis of PS40. Two major spots of TLC prepared by preparative thin layer chromatography (PTLC) were revealed to contain So-EO(20)-monopalmitate or So-EO(20)-dipalmitate by LC/MS. We also analyzed the extract from cocoa mix containing PS60 in SIM mode by LC/MS and found that it contained So-EO(20)-monostearate, tristearate and monopalmitate, the constituents of PS60. These results show that LC/MS analysis in SIM mode using Na+ adducts of So-EO(20)-FA(1〜3) as selected ions is useful not only for the analysis of compositional profile of PS itself, but for qualitative analysis of PS in food.
  • Kumada H, Haishima Y, Watanabe K, Hasegawa C, Tsuchiya T, Tanamoto K, Umemoto T
    Oral Microbiol Immunol., 23 60-69, 2008  
  • Naoki Sugimoto, Ryo Koike, Noriko Furusho, Makoto Tanno, Chikako Yomota, Kyoko Sato, Takeshi Yamazaki, Kenichi Tanamoto
    FOOD ADDITIVES AND CONTAMINANTS, 24(8) 799-806, Aug, 2007  
    Guidelines for the oxyethylene group (EO) content of polysorbates are set by the Food and Agriculture Organization/World Health Organization joint Expert Committee on Food Additives. However, the classical titration method for EO determination is difficult and time-consuming. Here, we show that quantitative 'H-nuclear magnetic resonance spectroscopy can determine the EO contents of polysorbates rapidly and simply. The EO signals were identified through comparisons with sorbitan monolaurate and poly(ethylene glycol) distearate. Potassium hydrogen phthalate was used as an internal standard. The EO contents were estimated from the ratio of the signal intensities of EO to the internal standard. Two nuclear magnetic resonance systems were used to validate the proposed method. The EO content of commercial polysorbates 20, 60, 65, and 80 was determined to be within the recommended limits using this technique. Our approach thus represents an additional or alternative method of determining the EO contents of polysorbates.
  • Masahiko Yamamoto, Changjin Zhu, Lui Yi, Zheng Rong, Yoshie Miura, Minoru Izumi, Shuhei Nakajima, Ken-ichi Tanamoto, Sakayu Shimizu, Naomichi Baba
    BIOSCIENCE BIOTECHNOLOGY AND BIOCHEMISTRY, 71(4) 1078-1082, Apr, 2007  
    Novel fatty acyl and phospholipid derivatives of pyrrole polyamide were synthesized. Their cytotoxicity against a cancer cell line of MT-4 cells and those infected by human immunodeficiency virus (HIV) was examined. Although no anti-HIV activity was found, their cytotoxicitty against the cancer cells was significantly enhanced by introducing a lipophilic group into the pyrrole polyamide.
  • 横田伸一, 大西貴弘, 室井正志, 藤井鴨弘, 棚元 憲一, 天野憲一
    エンドトキシン研究, 10 15-23, 2007  
    低エンドトキシン活性を示す<I>Helicobacter pylori</I>リポ多糖の炎症反応惹起機構について解説した。
  • 塩入利一, 室井正志, 畑尾史彦, 西田正人, 小川利久, 三村芳和, 上西紀夫, 棚元 憲一
    エンドトキシン研究, 10 133-138, 2007  
    エンドトキシンによって誘導される血管内皮細胞のアポトーシスを解説した。
  • 西田正人, 畑尾史彦, 比企直樹, 塩入利一, 小川利久, 三村芳和, 上西紀夫, 室井正志, 棚元 憲一
    エンドトキシン研究, 10 126-132, 2007  
    TLR4強制発現細胞を用いた血中エンドトキシン活性測定法について解説した。
  • Mutsuga M., Kawamura Y., Tanamoto K.
    Japanese Journal of Food Chemistry and Safety, 14(2) 87-92-92, 2007  
    Eight kinds of polylactide (PLA) made by two manufactures were studied on their properties of pellets and sheets. Their relative viscosity (Rv) values against chloroform were from 2.8 to 4.1, and molecular weight (Mw) were from 120,000 to 160,000. The D-lactic acid contents of sheets were from less than 1% to 11.3%. There was the correlation between Rv value and Mw, except a sheet produced by higher content of D-lactic acid, which showed lower Rv value. Residues of free lactide were 169-1610 μg/g in the sheets. On metal analysis, all sheets contained tin, but no other special metal. It was suggested that 2-ethylhexanoic acid tin (II) salt was used as catalyst in their polymerization. The levels of tin were from 3.4 to 31.8 μg/g, however migration into 4% acetic acid was not observed. In the overall migration test and the consumption of potassium permanganate test, each sample showed low levels. Lactic acid and lactide which were expected to be main migrants were not estimated by overall migration test, because they were vaporized during the heating at 105℃. It is, therefore, necessary to establish the migration test for lactic acid and lactide.
  • Ohnishi T, Muroi M, Tanamoto K
    FEMS Immunol. Med. Microbiol., 51 84-91, 2007  
  • UekusaY, Sugimoto N, Sato K, Yun Y.S, Kunugi A, Yamazaki Y, Tanamoto K
    Chem. Pharm. Bull., 55 1643-1646, 2007  
  • 大西貴弘, 室井正志, 棚元 憲一
    エンドトキシン研究, 10 120-125, 2007  
    MD-2非発現細胞における新しいLPS認識機構について解説した。
  • 室井正志, 棚元 憲一
    エンドトキシン研究, 10 115-119, 2007  
    IRAK-1過剰発現によるTRAF6蛋白のproteasome依存性の減少機構について解説した。
  • Ohnishi T, Yoshida T, Igarashi A, Muroi M, Tanamoto K
    FEMS Immunol. Med. Microbiol., 2007  
  • Sugimoto N, Tada A, Yamazaki T
    J. Food. Hyg. Soc. Japan, 48 106-111, 2007  
  • Tada A, Masuda A, Sugimoto N, Yamagata K, Yamazaki T
    J. Food. Hyg. Soc. Japan, 48 179-185, 2007  
  • M Mutsuga, Y Kawamura, Y Sugita-Konishi, Y Hara-Kudo, K Takatori, K Tanamoto
    FOOD ADDITIVES AND CONTAMINANTS, 23(2) 212-218, Feb, 2006  
    The levels of formaldehyde (FA) and acetaldehyde (AA) in polyethylene terephthalate (PET) bottles and in commercial mineral water are reported. All the water samples bottled in Japan contained detectable levels of FA (10.1 - 27.9 mu g l(-1)) and AA (44.3 - 107.8 mu g l(-1)). Of 11 European bottled water samples, eight did not contain either FA or AA, while the remaining three had detectable levels of FA (7.4 - 13.7 mg l(-1)) and AA (35.9 - 46.9 mu g l(-1)). In three North American bottled water samples, two contained FA (13.6 and 19.5 mu g l(-1)) and AA (41.4 and 44.8 mu g l(-1)), and one did not. Regardless of the region of origin, all the sterilized water samples contained FA and AA, whilst in contrast, none of the unsterilized water without carbonate contained FA or AA. Of the carbonated water samples, three contained FA and AA, and one did not. When fortified with FA and AA, the commercial water sample without otherwise detectable FA and AA was able to reduce levels, although the commercial water sample containing FA and AA could not. The presence of bacteria in the commercial water samples was investigated using an ATP-based bioluminescent assay and heterotrophic plate count method. The commercial water without FA and AA contained heterotrophic bacteria, whilst the commercial water with FA and AA did not contain detectable bacteria. It is suggested that in this case both FA and AA migrated from PET materials, but were subsequently decomposed by the heterotrophic bacteria in the unsterilized water.

Books and Other Publications

 15

Presentations

 18