J Koyama

Summary

Affiliation: Kobe Pharmaceutical University
Country: Japan

Publications

  1. ncbi request reprint Cyclopentene dialdehydes from Tabebuia impetiginosa
    J Koyama
    Kobe Pharmaceutical University, Japan
    Phytochemistry 53:869-72. 2000
  2. doi request reprint Simultaneous determination of histamine and prostaglandin D2 using an LC-ESI-MS/MS method with positive/negative ion-switching ionization modes: application to the study of anti-allergic flavonoids on the degranulation of KU812 cells
    Junko Koyama
    Kobe Pharmaceutical University, Higashinada, Kobe, Japan
    Anal Bioanal Chem 401:1385-92. 2011
  3. ncbi request reprint Simultaneous determination of anthraquinones, their 8-beta-D-glucosides, and sennosides of Rhei Rhizoma by capillary electrophoresis
    Junko Koyama
    Kobe Pharmaceutical University, Kobe 658 8558, Japan
    Chem Pharm Bull (Tokyo) 53:573-5. 2005
  4. ncbi request reprint Correlation between reduction potentials and inhibitory effects on Epstein-Barr virus activation of poly-substituted anthraquinones
    Junko Koyama
    Faculty of Pharmaceutical Sciences, Kobe Pharmaceutical University, Higashinada, Kobe 658 8558, Japan
    Cancer Lett 225:193-8. 2005
  5. ncbi request reprint Correlation between reduction potentials and inhibitory effects on Epstein-Barr virus activation by emodin derivatives
    Junko Koyama
    Faculty of Pharmaceutical Sciences, Kobe Pharmaceutical University, Higashinada, Kobe 658 8558, Japan
    Cancer Lett 241:263-7. 2006
  6. ncbi request reprint Antiallergic activity of aqueous extracts and constituents of Taxus yunnanensis
    Junko Koyama
    Kobe Pharmaceutical University, Japan
    Biol Pharm Bull 29:2310-2. 2006
  7. ncbi request reprint Simultaneous determination of anthraquinones in rhubarb by high-performance liquid chromatography and capillary electrophoresis
    Junko Koyama
    Kobe Pharmaceutical University, Higashinada ku, Kobe 658 8558, Japan
    J Chromatogr A 1145:183-9. 2007
  8. ncbi request reprint Anti-infective quinone derivatives of recent patents
    Junko Koyama
    Faculty of Pharmaceutical Sciences, Kobe Pharmaceutical University, Higashinada ku, Kobe 658 8558, Japan
    Recent Pat Antiinfect Drug Discov 1:113-25. 2006
  9. doi request reprint Correlation between oxidation potentials and inhibitory effects on Epstein-Barr virus activation of flavonoids
    Junko Koyama
    Faculty of Pharmaceutical Sciences, Kobe Pharmaceutical University, Higashinada, Kobe 658 8558, Japan
    Cancer Lett 263:61-6. 2008
  10. doi request reprint Correlation between reduction potentials and inhibitions of Epstein-Barr virus activation by anthraquinone derivatives
    Junko Koyama
    Faculty of Pharmaceutical Sciences, Kobe Pharmaceutical University, Higashinada, Kobe 658 8558, Japan
    Bioorg Med Chem Lett 18:4106-9. 2008

Collaborators

Detail Information

Publications32

  1. ncbi request reprint Cyclopentene dialdehydes from Tabebuia impetiginosa
    J Koyama
    Kobe Pharmaceutical University, Japan
    Phytochemistry 53:869-72. 2000
    ..The structures were established by analysis of spectroscopic data. These compounds showed anti-inflammatory activity...
  2. doi request reprint Simultaneous determination of histamine and prostaglandin D2 using an LC-ESI-MS/MS method with positive/negative ion-switching ionization modes: application to the study of anti-allergic flavonoids on the degranulation of KU812 cells
    Junko Koyama
    Kobe Pharmaceutical University, Higashinada, Kobe, Japan
    Anal Bioanal Chem 401:1385-92. 2011
    ..2% and 7.8% for PGD(2). This method was used to evaluate the anti-allergic effects of 26 flavonoids and sodium cromoglicate which are first-line anti-allergic drugs. Of these compounds, baicalein and morin were the most potent inhibitors...
  3. ncbi request reprint Simultaneous determination of anthraquinones, their 8-beta-D-glucosides, and sennosides of Rhei Rhizoma by capillary electrophoresis
    Junko Koyama
    Kobe Pharmaceutical University, Kobe 658 8558, Japan
    Chem Pharm Bull (Tokyo) 53:573-5. 2005
    ..The running electrolyte used in this method was 0.005 M alpha-cyclodextrin in 0.03 M borate buffer (pH 10.0) containing 20% acetonitrile, with an applied voltage of 20 kV...
  4. ncbi request reprint Correlation between reduction potentials and inhibitory effects on Epstein-Barr virus activation of poly-substituted anthraquinones
    Junko Koyama
    Faculty of Pharmaceutical Sciences, Kobe Pharmaceutical University, Higashinada, Kobe 658 8558, Japan
    Cancer Lett 225:193-8. 2005
    ..It has been further shown that the correlation can be enhanced by introducing log P as an additional parameter...
  5. ncbi request reprint Correlation between reduction potentials and inhibitory effects on Epstein-Barr virus activation by emodin derivatives
    Junko Koyama
    Faculty of Pharmaceutical Sciences, Kobe Pharmaceutical University, Higashinada, Kobe 658 8558, Japan
    Cancer Lett 241:263-7. 2006
    ..The electronic properties, i.e. LUMO energy and atomic charges of carbon at the 9-position (C(9)) and oxygen at the 11-position (O(11)), may also be useful for estimating the inhibitory effect on EBV-EA activation...
  6. ncbi request reprint Antiallergic activity of aqueous extracts and constituents of Taxus yunnanensis
    Junko Koyama
    Kobe Pharmaceutical University, Japan
    Biol Pharm Bull 29:2310-2. 2006
    ..A new neolignan, 2-[2-hydroxy-5-(3-hydroxypropyl)-3-methoxyphenyl]-1-(4-hydroxy-3-methoxyphenyl)propane-1,3-diol, was isolated from the wood of Taxus yunnanensis...
  7. ncbi request reprint Simultaneous determination of anthraquinones in rhubarb by high-performance liquid chromatography and capillary electrophoresis
    Junko Koyama
    Kobe Pharmaceutical University, Higashinada ku, Kobe 658 8558, Japan
    J Chromatogr A 1145:183-9. 2007
    ....
  8. ncbi request reprint Anti-infective quinone derivatives of recent patents
    Junko Koyama
    Faculty of Pharmaceutical Sciences, Kobe Pharmaceutical University, Higashinada ku, Kobe 658 8558, Japan
    Recent Pat Antiinfect Drug Discov 1:113-25. 2006
    ..This review will focus on the preparation, therapeutic application, and administration of several benzoquinones, naphthoquinones, and anthraquinones having anti-infective, e.g. antiviral and antibacterial activities, in recent patents...
  9. doi request reprint Correlation between oxidation potentials and inhibitory effects on Epstein-Barr virus activation of flavonoids
    Junko Koyama
    Faculty of Pharmaceutical Sciences, Kobe Pharmaceutical University, Higashinada, Kobe 658 8558, Japan
    Cancer Lett 263:61-6. 2008
    ..Furthermore, multiple regression analysis revealed that the solvent-accessible surface area (SASA) was a useful parameter for estimating the inhibitory effects of flavonoids on EBV-EA activation...
  10. doi request reprint Correlation between reduction potentials and inhibitions of Epstein-Barr virus activation by anthraquinone derivatives
    Junko Koyama
    Faculty of Pharmaceutical Sciences, Kobe Pharmaceutical University, Higashinada, Kobe 658 8558, Japan
    Bioorg Med Chem Lett 18:4106-9. 2008
    ..It was further shown that the correlation could be enhanced by including LUMO energy and the number of hydroxy groups as additional parameters...
  11. doi request reprint Development of an LC-ESI-MS/MS method for the determination of histamine: application to the quantitative measurement of histamine degranulation by KU812 cells
    Junko Koyama
    Kobe Pharmaceutical University, Higashinada, Kobe 658 8558, Japan
    J Chromatogr B Analyt Technol Biomed Life Sci 877:207-12. 2009
    ..Of these compounds, taxiresinol and isotaxiresinol were more inhibitory than sodium cromoglicate...
  12. doi request reprint Characterization of emodin metabolites in Raji cells by LC-APCI-MS/MS
    Junko Koyama
    Kobe Pharmaceutical University, Higashinada, Kobe 658 8558, Japan
    Bioorg Med Chem 17:7493-9. 2009
    ..In addition to the major metabolite 8-O-methylemodin, four other metabolites were assigned as omega-hydroxyemodin, 3-O-methyl-omega-hydroxyemodin, 3-O-methylemodin (physcion), and chrysophanol...
  13. doi request reprint Correlation between cytotoxic activities and reduction potentials of heterocyclic quinones
    Junko Koyama
    Faculty of Pharmaceutical Sciences, Kobe Pharmaceutical University, Higashinada, Kobe, Japan
    Molecules 15:6559-69. 2010
    ..These results suggested that reduction-oxidation potentials could be a useful method for the discovery of novel antitumor agents...
  14. ncbi request reprint Correlation of redox potentials and inhibitory effects on Epstein-Barr virus activation of 2-azaanthraquinones
    Junko Koyama
    Faculty of Pharmaceutical Sciences, Kobe Pharmaceutical University, Higashinada, Kobe 658 8558, Japan
    Cancer Lett 212:1-6. 2004
    ..It has been further shown that the correlation can be enhanced by introducing an electronic properties, i.e. the atomic charges at the C5 and O12 atoms in the quinone skeleton ring and the HOMO energy as additional parameters...
  15. ncbi request reprint Correlation of redox potentials and inhibitory effects on Epstein-Barr virus activation of naphthoquinones
    Junko Koyama
    Faculty of Pharmaceutical Sciences, Kobe Pharmaceutical University, Higashinada, Kobe 658, Japan
    Cancer Lett 201:25-30. 2003
    ..It has been further shown that the correlation can be enhanced by introducing an electronic property, i.e. the atomic charges at the C(4) and O(10) atoms in the quinone skeleton ring as additional parameters...
  16. ncbi request reprint Capillary electrophoresis for simultaneous determination of emodin, chrysophanol, and their 8-beta-D-glucosides
    Junko Koyama
    Kobe Pharmaceutical University, Higashinada ku, Japan
    Chem Pharm Bull (Tokyo) 51:418-20. 2003
    ..The running electrolyte used in this method was 0.005 M alpha-cyclodextrin in 0.03 M borate buffer (pH 10.5) containing 10% acetonitrile, with an applied voltage of 20 kV...
  17. ncbi request reprint Micellar electrokinetic chromatography (MEKC) separation of furanonaphthoquinones from Tabebuia impetiginosa
    J Koyama
    Kobe Pharmaceutical University, Japan
    Chem Pharm Bull (Tokyo) 48:873-5. 2000
    ....
  18. ncbi request reprint Enantiomeric separation by cyclodextrin modified capillary zone electrophoresis (CD-CZE) of quaternary tetrahydroprotoberberine alkaloids
    J Koyama
    Kobe Pharmaceutical University, Japan
    Chem Pharm Bull (Tokyo) 48:1790-2. 2000
    ..5 or 3) containing 10% acetonitrile with an applied voltage of 20 kV. This method was applied toward the enantioselective bio-conversion of quaternary tetrahydroprotoberberine N-metho salts in cultured cells of Corydalis species...
  19. ncbi request reprint Bianthraquinones from Cassia siamea
    J Koyama
    Kobe Pharmaceutical University, Japan
    Phytochemistry 56:849-51. 2001
    ..The structures were established by analysis of spectroscopic data and 7-chloro-1,1',6,8,8'-pentahydroxy-3,3'-dimethyl[2,2'-bianthracene]-9,9',10,10'-tetrone was determined on the direct comparison with synthetic compound...
  20. ncbi request reprint Inhibitory effects of anthraquinones and bianthraquinones on Epstein-Barr virus activation
    J Koyama
    Faculty of Pharmaceutical Sciences, Kobe Pharmaceutical University, Higashinada, 658, Kobe, Japan
    Cancer Lett 170:15-8. 2001
    ..Anthraquinone monomers showed higher anti-tumor promoting activity than that of bianthraquinones...
  21. ncbi request reprint Correlation with redox potentials and inhibitory effects on Epstein-Barr virus activation of azaanthraquinones
    J Koyama
    Kobe Pharmaceutical University, Higashinada, Japan
    Chem Pharm Bull (Tokyo) 49:1214-6. 2001
    ..It has further been shown that the correlation can be made better by introducing an electronic property, i.e., the atomic charge at O11 as an additional parameter...
  22. ncbi request reprint Chemopreventive effects of emodin and cassiamin B in mouse skin carcinogenesis
    Junko Koyama
    Faculty of Pharmaceutical Sciences, Kobe Pharmaceutical University, Higashinada, Kobe 658, Japan
    Cancer Lett 182:135-9. 2002
    ....
  23. ncbi request reprint Capillary electrophoresis of anthraquinones from Cassia siamea
    Junko Koyama
    Kobe Pharmaceutical University, Kobe, Japan
    Chem Pharm Bull (Tokyo) 50:1103-5. 2002
    ..Application of this technique in the determination of the main bianthraquinones, cassiamin A and cassiamin B, of Cassia siamea is demonstrated in this paper...
  24. ncbi request reprint Structure-activity relations of azafluorenone and azaanthraquinone as antimicrobial compounds
    Junko Koyama
    Faculty of Pharmaceutical Sciences, Kobe Pharmaceutical University, Higashinada ku, Kobe 658 8558, Japan
    Bioorg Med Chem Lett 15:1079-82. 2005
    ..In addition, correlations among reduction potential, hydrophobic parameter, and antimicrobial activity were discussed...
  25. doi request reprint Biotransformation of phenolic tetrahydroprotoberberines in plant cell cultures followed by LC-NMR, LC-MS, and LC-CD
    Kinuko Iwasa
    Kobe Pharmaceutical University, 4 19 1 Motoyamakita, Higashinada ku, Kobe shi 658 8558, Japan
    J Nat Prod 73:115-22. 2010
    ..cordata and C. ochotensis var. raddeana, which was distinct from O-methylation in N. domestica, in which 7 was O-methylated at both C-11 and C-10. Stereoselective O-demethylation [(S)-5 to (S)-18] occurred in N. domestica...
  26. ncbi request reprint Higher radical scavenging activities of polyphenolic antioxidants can be ascribed to chemical reactions following their oxidation
    Hiroki Hotta
    Department of Chemistry, Faculty of Science, Kobe University, Nada, Japan
    Biochim Biophys Acta 1572:123-32. 2002
    ..In this study, we have proposed a possible mechanism for the oxidation of polyphenols, in which the oxidizable -OH moieties are reproduced through an oxidative dimerization (or more highly polymerization)...
  27. ncbi request reprint Mechanistic study of the oxidation of caffeic acid by digital simulation of cyclic voltammograms
    Hiroki Hotta
    Department of Chemistry, Faculty of Science, Kobe University, Nada, Kobe 657 8501, Japan
    Anal Biochem 303:66-72. 2002
    ..Evaluations of the rate constants for the chemical reactions have further suggested that the chemical reactions are dimerization reactions...
  28. ncbi request reprint Paraquat detoxicative system in the mouse liver postmitochondrial fraction
    Hiroki Shimada
    Department of Anatomy, Kanazawa Medical University, Uchinada, Ishikawa 920 0293, Japan
    Arch Biochem Biophys 402:149-57. 2002
    ....
  29. ncbi request reprint A new quassinoid, ailantinol H, from Ailanthus altissima
    Sadaaki Tamura
    Faculty of Integrated Arts and Sciences, Hiroshima University, 1 7 1 Kagamiyama, Higashi hiroshima 739 8521, Japan
    Nat Prod Res 20:1211-5. 2006
    ..A new quassinoid, ailantinol H, was isolated from the aerial parts of Ailanthus altissima. The structure was elucidated based on spectral evidence...
  30. ncbi request reprint Furanonaphthoquinones cause apoptosis of cancer cells by inducing the production of reactive oxygen species by the mitochondrial voltage-dependent anion channel
    Eriko Simamura
    Molecular and Cell Structural Science, Kanazawa Medical University, Uchinada, Ishikawa, Japan
    Cancer Biol Ther 5:1523-9. 2006
    ..These results indicate that the anticancer activity of furanonaphthoquinones depends on the production of reactive oxygen species by mitochondrial permeability transition pores including the VDAC...
  31. ncbi request reprint Mitochondrial damage prior to apoptosis in furanonaphthoquinone treated lung cancer cells
    Eriko Simamura
    Department of Anatomy, Kanazawa Medical University, Uchinada, Ishikawa 920 0293, Japan
    Cancer Detect Prev 27:5-13. 2003
    ..The higher dose of 5 microg/ml induced necrosis via severe mitochondrial breakage. These results showed that FNQ3 targets the mitochondria of A549 cells to produce a reactive oxygen species resulting in apoptosis and necrosis...
  32. ncbi request reprint Three new quassinoids, ailantinol E, F, and G, from Ailanthus altissima
    Sadaaki Tamura
    Faculty of Integrated Arts and Sciences, Hiroshima University, 1 7 1 Kagamiyama, Higashi hiroshima 739 8521, Japan
    Chem Pharm Bull (Tokyo) 51:385-9. 2003
    ..The new quassinoids were found to show potent activity without showing any cytotoxicity. The screening for inhibitors against nitric oxide donor action was also conducted using the new quassinoids and some standard samples...