Takuya Koseki


Affiliation: Yamagata University
Country: Japan


  1. Koseki T, Ishikawa M, Kawasaki M, Shiono Y. β-Diglycosidases from microorganisms as industrial biocatalysts: biochemical characteristics and potential applications. Appl Microbiol Biotechnol. 2018;102:8717-8723 pubmed publisher
    ..The present paper reviews the biochemical characteristics and potential industrial applications of microbial β-diglycosidases that break down plant diglycoconjugated flavonoids. ..
  2. Koseki T, Ichikawa K, Sasaki K, Shiono Y. Characterization of a novel Aspergillus oryzae tannase expressed in Pichia pastoris. J Biosci Bioeng. 2018;126:553-558 pubmed publisher
    ..Therefore, recombinant AoTanB showed a decrease in catalytic efficiency (kcat/Km value) compared to recombinant AoTanA was due to considerably lower kcat value. ..
  3. Koseki T, Mese Y, Nishibori N, Masaki K, Fujii T, Handa T, et al. Characterization of an alpha-L-rhamnosidase from Aspergillus kawachii and its gene. Appl Microbiol Biotechnol. 2008;80:1007-13 pubmed publisher
  4. Koseki T, Otsuka M, Mizuno T, Shiono Y. Mutational analysis of Kex2 recognition sites and a disulfide bond in tannase from Aspergillus oryzae. Biochem Biophys Res Commun. 2017;482:1165-1169 pubmed publisher
    ..Meanwhile, the ?KR variant exhibited higher activity compared to the wild-type. The activities of the C194A and C502A variants decreased considerably (<0.24% of the wild-type) toward methyl gallate. ..
  5. Ishikawa M, Kawasaki M, Shiono Y, Koseki T. A novel Aspergillus oryzae diglycosidase that hydrolyzes 6-O-?-L-rhamnosyl-?-D-glucoside from flavonoids. Appl Microbiol Biotechnol. 2018;102:3193-3201 pubmed publisher
    ..Meanwhile, kcat value toward hesperidin was lower than those toward kaempferol-3-O-rutinoside and rutin. Overall, the catalytic efficiency (kcat/K m ) was highest for kaempferol-3-O-rutinoside. ..
  6. Koseki T, Hori A, Seki S, Murayama T, Shiono Y. Characterization of two distinct feruloyl esterases, AoFaeB and AoFaeC, from Aspergillus oryzae. Appl Microbiol Biotechnol. 2009;83:689-96 pubmed publisher
    ..Ferulic acid was efficiently released from wheat arabinoxylan when both esterases were applied with xylanase from Thermomyces lanuginosus. Both recombinant proteins also exhibited hydrolytic activity toward chlorogenic acid...
  7. Koseki T, Mihara K, Murayama T, Shiono Y. A novel Aspergillus oryzae esterase that hydrolyzes 4-hydroxybenzoic acid esters. FEBS Lett. 2010;584:4032-6 pubmed publisher
    ..Finally, the enzyme decreased the antimicrobial activity of parabens against A. oryzae via hydrolysis of the ester bond present in butyl 4-hydroxybenzoic acid...
  8. Mizuno T, Shiono Y, Koseki T. Biochemical characterization of Aspergillus oryzae native tannase and the recombinant enzyme expressed in Pichia pastoris. J Biosci Bioeng. 2014;118:392-5 pubmed publisher
  9. Islam J, Koseki T, Watanabe K, Budijanto S, Oikawa A, Alauddin M, et al. Dietary Supplementation of Fermented Rice Bran Effectively Alleviates Dextran Sodium Sulfate-Induced Colitis in Mice. Nutrients. 2017;9: pubmed publisher
    ..These results suggest that FRB could comprise an effective potential preventive agent for ulcerative colitis. ..

More Information


  1. Ishikawa M, Shiono Y, Koseki T. Biochemical characterization of Aspergillus oryzae recombinant ?-l-rhamnosidase expressed in Pichia pastoris. J Biosci Bioeng. 2017;124:630-634 pubmed publisher
    ..Its high catalytic efficiency (kcat/Km) toward rutin was results of its low Km value while its high catalytic efficiency toward hesperidin was results of a considerably high kcat value. ..