研究者情報

マスター

アカウント（マスター）

• 氏名

  幸田　圭一(コウダ　ケイイチ), コウダ　ケイイチ

所属（マスター）

• 農学研究院　基盤研究部門　森林科学分野

所属（マスター）

• 農学研究院　基盤研究部門　森林科学分野

独自項目

syllabus

• 2021, 森林資源科学特論, Advanced Forest Resources Science, 修士課程, 農学院, 森林資源、樹木/林木、木材、バイオリファイナリ?、きのこ、生理活性物質
• 2021, 森林資源科学特論演習, Advanced Seminar on Forest Resources Science, 修士課程, 農学院, 森林資源、樹木/林木、木材、バイオリファイナリ?、きのこ、生理活性物質
• 2021, 林産学特論Ⅰ, Advanced Forest Products Science I, 修士課程, 農学院, 木質バイオマス、持続的利用、再生可能、有効利用、技術論
• 2021, 林産学特論演習Ⅰ, Advanced Seminar on Forest Products I, 修士課程, 農学院, 木質バイオマス、持続的利用、再生可能、有効利用、技術論、基礎、実践
• 2021, 環境化学, Environmental Chemistry, 学士課程, 農学部, 大気・河川・湖沼・海洋・地下水・土壌の汚染、人工公害物質、ミスト、バイオレメディエーション、バイオマス廃棄物の資源化・循環、ＬＣＡ、植物ストレス
• 2021, 高分子学概論, Introduction to Polymer Science, 学士課程, 農学部, 生体高分子、天然高分子、合成高分子、機能と構造、分子量
• 2021, 林産学実習, Practical Field Work on Conversion and Engineering of Forest Products, 学士課程, 農学部, 木炭、活性炭、木酢液、きのこ、製材、樹幹解析、繊維傾斜、等級区分
• 2021, パルプ・製紙学, Pulp and Paper, 学士課程, 農学部, パルプ、蒸解、漂白、抄紙、紙の基本物性、機能紙
• 2021, 木質バイオマス変換化学, Applied Chemistry on Woody Biomass Conversion, 学士課程, 農学部, 木質バイオマス、バイオリファイナリー、化学的／生化学的変換、機能性材料
• 2021, 林産製造学実験, Laboratory Work on Woody Biomass Conversion, 学士課程, 農学部, 紙、パルプ、セルロース誘導体、リグニン誘導体
• 2021, 英語演習, English Seminar, 学士課程, 全学教育, 森林生態系の管理・保全、樹木の構造と性質、木質バイオマスの利活用
• 2021, 一般教育演習(ﾌﾚｯｼｭﾏﾝｾﾐﾅｰ), Freshman Seminar, 学士課程, 全学教育, 組織構造、環境応答、強度、木質バイオマス、樹木の化学成分、オゾン・酸性雨、保全管理、森林管理、生物多様性、生態系サービス、国土保全、森林政策

researchmap

プロフィール情報

学位

• 博士（農学）（東京大学）

プロフィール情報

• 姓

  幸田, コウダ

• 名

  圭一, ケイイチ

• ID各種

  200901054860589835

対象リソース

http://www.agr.hokudai.ac.jp/fres/forchem/

業績リスト

研究キーワード

• 炭素循環   リター（植物遺骸）   パルプ化   漂白   バイオリファイナリー   生分解   化学改質   木質バイオマス   リグニン   Wood Chemistry   

研究分野

• ライフサイエンス / 木質科学 / 木材化学

経歴

• 2020年07月 - 現在 北海道大学 大学院農学研究院 基盤研究部門 准教授
• 2015年04月 - 2020年06月 北海道大学 大学院農学研究院 基盤研究部門 講師
• 2011年08月 - 2015年03月 北海道大学 大学院農学研究院 環境資源学部門 講師
• 2007年04月 - 2011年07月 北海道大学 大学院農学研究院 環境資源学部門 助教
• 2006年04月 - 2007年03月 北海道大学 大学院農学研究院 環境資源学部門 助手
• 2000年04月 - 2006年03月 北海道大学 大学院農学研究科 環境資源学専攻 助手

学歴

• 1997年04月 - 2000年03月   東京大学   大学院 農学生命科学研究科   生物材料科学専攻（博士課程）
• 1997年04月 - 2000年03月   東京大学
• 1995年04月 - 1997年03月   東京大学   大学院 農学生命科学研究科   生物材料科学専攻（修士課程）
• 1995年04月 - 1997年03月   東京大学
• 1993年04月 - 1995年03月   東京大学   農学部   林産学科
• 1993年04月 - 1995年03月   東京大学

委員歴

• 2021年11月 - 現在   リグニン学会   理事
• 2015年04月 - 現在   日本木材学会   機関幹事（北海道大学）
• 2009年04月 - 現在   セルロース学会   北海道・東北支部編集委員
• 2021年06月 - 2023年05月   日本木材学会 北海道支部   常任理事（庶務担当）
• 2013年06月 - 2021年03月   日本木材学会 バイオマス変換研究会   幹事
• 2017年04月 - 2019年03月   日本木材学会 バイオマス変換研究会   代表幹事
• 2015年06月 - 2017年06月   日本木材学会北海道支部   研究会理事
• 2015年06月 - 2017年03月   日本木材学会 バイオマス変換研究会   会計幹事
• 2013年04月 - 2015年03月   日本木材学会   編集委員
• 2012年04月 - 2015年03月   北方林業会   編集委員
• 2013年06月 - 2014年05月   日本木材学会北海道支部   常任理事（庶務担当）
• 2012年06月 - 2013年05月   日本木材学会北海道支部   常任理事（会計補佐担当）
• 2010年06月 - 2012年05月   高分子学会北海道支部   事務局担当（支部長付）   高分子学会北海道支部
• 2009年06月 - 2011年05月   日本木材学会北海道支部   研究会理事   日本木材学会北海道支部
• 2006年06月 - 2007年05月   日本木材学会北海道支部   常任理事（庶務担当）   日本木材学会北海道支部
• 2005年06月 - 2006年05月   日本木材学会北海道支部   常任理事（会計補佐担当）
• 2001年06月 - 2003年05月   日本木材学会北海道支部   研究会理事   日本木材学会北海道支部
• 2001年06月 - 2003年05月   日本木材学会北海道支部   評議員   日本木材学会北海道支部

受賞

• 2018年11月 リグニン討論会事務局 第63回リグニン討論会 優秀口頭発表賞
   Assembly of electric double layer capacitor with electrode made from lignin and ionic liquid as an electrolyte 

  受賞者: Nutthira Pakkang;Keiichi Koda;Yasumitsu Uraki
• 2018年10月 日本木材学会北海道支部 2018年度・第16回北の木材科学賞（口頭発表部門）
   電気二重層キャパシタ用セパレータとしてのセルロースナノファイバー強化リグニンポリエステルフィルム 

  受賞者: Shogo Taira;Keiichi Koda;Yasumitsu Uraki
• 2017年11月 日本木材学会北海道支部 2017年度・第15回北の木材科学賞（口頭発表部門）
   リグニン形成におけるヘミセルロースの機能 

  受賞者: 古川貴大;吉永 新;高部圭司;松尾朱実;玉井 裕;幸田圭一;浦木康光
• 2015年11月 第60回リグニン討論会事務局 第60回リグニン討論会G賞（口頭発表部門）
   数種の単離リグニンからの電気二重層用電極の調製 

  受賞者: 游 翔宇;段 軍磊;幸田圭一;浦木康光;山田竜彦;久保智史参照URL： http://www.agr.hokudai.ac.jp/news/2015/12/post-642.html
• 2015年11月 日本木材学会北海道支部 2015年度・第13回北の木材科学賞（展示発表部門）
   水溶性酢酸セルロースの電界紡糸とコンポジット化 

  受賞者: 鶴原正啓;幸田圭一;浦木康光参照URL： http://www.agr.hokudai.ac.jp/news/2015/12/post-644.html
• 2015年11月 日本木材学会北海道支部 2015年度・第13回北の木材科学賞（口頭発表部門）
   PEGリグニン由来の電気二重層キャパシタ用セパレータの開発 

  受賞者: 久保田 惇;磯崎友史;山田竜彦;幸田圭一;浦木康光参照URL： http://www.agr.hokudai.ac.jp/news/2015/12/post-643.html
• 2014年11月 日本木材学会北海道支部 2014年度・第12回北の木材科学賞（口頭発表部門）
   バイオエタノール生産に有用な両親媒性リグニン誘導体 

  受賞者: 山本陽子;Ningning Cheng;五十嵐圭日子;幸田圭一;浦木康光
• 2014年03月 日本森林学会 日本森林学会学生ポスター賞
   遡上したサケがもたらす窒素の落葉層への滞留 

  受賞者: 福井喬史;宮本敏澄;長坂 有;長坂晶子;幸田圭一;玉井 裕;矢島 崇
• 2013年11月 日本木材学会北海道支部 2013年度・第11回北の木材科学賞（展示発表部門）
   香気成分の定量的分析によるインドネシア産沈香の評価 

  受賞者: 石井貴史;幸田圭一;玉井 裕;Ina Winarni;Maman Turjama;浦木康光
• 2012年11月 日本木材学会北海道支部 2012年度・第10回北の木材科学賞（展示発表部門）
   ミズナラ緑葉に含まれるリグニンの地域間差異 

  受賞者: 川口 新;幸田圭一;宮本敏澄;浦木康光
• 2012年11月 日本木材学会北海道支部 2012年度・第10回北の木材科学賞（口頭発表部門）
   ヒドロキシプロピルセルロースゲルの熱応答性 －架橋剤が及ぼす影響－ 

  受賞者: 神田高志;幸田圭一;浦木康光
• 2012年06月 日本森林技術協会 第二十二回学生森林技術研究論文コンテスト 日本森林技術協会理事長賞
   オゾン酸化によるクラフトリグニンの改質-木質バイオマス系ポリカルボン酸の調製- 

  受賞者: 磯崎友史;主指導教員;幸田圭一;副指導教員;浦木康光
• 2011年11月 日本木材学会北海道支部 2011年度・第9回北の木材科学賞（展示発表部門）
   両親媒性リグニンを用いたAE型セメント分散剤の開発 

  受賞者: 麻生知裕;幸田圭一;山田竜彦;久保智史;中嶋 勇;浦木康光
• 2011年11月 日本木材学会北海道支部 2011年度・第9回北の木材科学賞（口頭発表部門）
   両親媒性リグニンによる酵素糖化の改善 

  受賞者: 及川千皓;イナ・ウィナルニ;幸田圭一;山田竜彦;浦木康光
• 2010年11月 日本木材学会北海道支部 2010年度・第8回北の木材科学賞（口頭発表部門）
   エレクトロスピニング法によるセルロースアセテート・ナノファイバーの調製とその利用 

  受賞者: 冨樫文哉;幸田圭一;浦木康光
• 2010年07月 セルロース学会 セルロース学会第17回香川大会 ポスター賞
   ヘミセルロース吸着ハニカムパターン化セルロースの調製とその利用 

  受賞者: 田崎裕佳;浦木康光;幸田圭一;山本貞明;藪 浩;下村政嗣
• 2010年 Oral Presentation Award at the 42nd annual meeting of Hokkaido Branch, Japan Wood Research Society, Asahikawa, Nov. 9, 2010
  
• 2010年 Poster Award at the 17th annual meeting of the Cellulose Society of Japan, Kagawa, Jul. 15-16, 2010
  
• 2009年11月 日本木材学会北海道支部 2009年度・第7回北の木材科学賞（口頭発表部門）
   高界面活性リグニン誘導体の調製とその分散性能の評価 

  受賞者: 本間春海;浦木康光;幸田圭一;久保智史;山田竜彦;松下泰幸;福島和彦
• 2009年 Oral Presentation Award at the 41st annual meeting of Hokkaido Branch, Japan Wood Research Society, Asahikawa, Nov. 9, 2009
  

論文

• A branched structure provides kraft lignins a denser morphology and a high molar mass for a given hydrodynamic radius

  Linping Wang, Kengo Shigetomi, Keiichi Koda, Aori Gele, Yasumitsu Uraki

  Holzforschung 74 6 551 - 558 2020年06月25日 [査読有り][通常論文]
   

  Size exclusion chromatography with multi-angle laser light-scattering detectors was applied for acetylated softwood and hardwood kraft lignins (Ac-SKL and Ac-HKL) and 8-O-4′ type of linear polymeric lignin model (Ac-M-8O4′) to compare their swelling behaviors. The plot of molar mass (MM) vs. retention time for Ac-M-8O4′ was similar to that of polystyrene, which revealed that Ac-M-8O4′ exhibited swelling behavior that was similar to that of polystyrene. However, the MM values of both Ac-KLs were larger than those of polystyrene standards at any retention time. This difference indicated that both Ac-KLs had a more compact structure than those of polystyrene and Ac-M-8O4′. One hypothesis is that the larger MM of both Ac-KLs stems from their branched structures. To verify this hypothesis, the frequency of 5-5′ interunit linkage in lignin samples was determined by ¹H NMR after nitrobenzene oxidation. A linear relationship between MM and 5-5′ abundance was observed in the high MM region.
• Cellulose acetate with CTA I polymorph can be defibrated into nanofibers to produce a highly transparent nanopaper

  Shogo Taira, Masataka Tsuruhara, Ryo Saito, Keiichi Koda, Yasumitsu Uraki, Haruo Konno, Shu Shimamoto

  Cellulose 27 9 4991 - 5001 2020年06月 [査読有り][通常論文]
  
• Preparation of kraft lignin-based activated carbon fiber electrodes for electric double layer capacitors using an ionic liquid electrolyte

  Nutthira Pakkang, Manish Kumar, Shogo Taira, Keiichi Koda, Kengo Shigetomi, Yasumitsu Uraki

  Holzforschung 74 6 577 - 588 2020年05月29日 [査読有り][通常論文]
   

  This article demonstrates the development of activated carbon fiber electrodes produced from hardwood kraft lignin (HKL) to fabricate electric double layer capacitors (EDLCs) with high energy and power densities using an ionic liquid (IL) electrolyte. A mixture solution of HKL, polyethylene glycol as a sacrificial polymer, and hexamethylenetetramine as a crosslinker in dimethylformamide/acetic acid (6/4) was electrospun, and the obtained fibers were easily thermostabilized, followed by carbonization and steam activation to yield activated carbon fibers (ACFs). The electrochemical performance of EDLCs assembled with the ACFs, 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIBF₄) as an IL electrolyte and a cellulosic separator was insufficient due to the low conductivity of the electrode. The conductivity of the electrode was improved successfully by spraying conductive carbon black (CB) onto the fibers mat during electrospinning. The CB containing electrodes with improved conductivity gave the resulting EDLCs a higher electrochemical performance, with an energy density of 91.5 Wh kg⁻¹ and a power density of 76.2 kW kg⁻¹.
• Effect of Vapor-Phase Surface Acetylation of Japanese Cedar Wood on Fungal Degradation and Dimensional Stability

  Yuu Hasegawa, Mitsunori Mori, Keiichi Koda, Yasumitsu Uraki

  Journal of Wood Chemistry and Technology 40 1 1 - 14 2020年01月02日 [査読有り][通常論文]
   

  Vapor-phase acetylation of heartwood in Japanese cedar wood (Cryptomeria japonica D. Don) was carried out as a surface acetylation method to elucidate the relationship between the depth of acetylated area and fungal decay resistance. The acetylated wood (VPAW), prepared with acetic anhydride vapor by heating at 80 degrees C for 72 h, indicated a significant fungal decay resistance and dimensional stability in water-soaking test, similar to liquid-phase acetylated wood (LPAW). The VPAW provided more than 15% of the weight percent gain (WPG) up to a depth of 7 mm from the wood surface, while LPAW gave similar to 20% WPG uniformly throughout the wood. However, 24-h vapor-phase acetylation, giving 15% WPG at a depth of 0-2 mm, showed insufficient fungal decay resistance. These results showed that at least 7 mm thickness of the acetylated region with 15% WPG was required to suppress the fungal decay of acetylated wood under laboratory conditions.
• Comparison of Dehydrogenation Polymers by Commercial Enzymes, Laccase from Rhus vernicifera and Horseradish Peroxidase

  Tatsuya Matsumoto, Keiichi Koda, Kengo Shigetomi, Manish Kumar, Yasumitsu Uraki

  Lignin 1 20 - 28 2020年01月 [査読有り][通常論文]
  
• Development of Lignin-Based Terpolyester Film and Its Application to Separator Material for Electric Double-Layer Capacitor

  Keiichi Koda, Shogo Taira, Atsushi Kubota, Tomofumi Isozaki, Xiangyu You, Yasumitsu Uraki, Kazuki Sugimura, Yoshiyuki Nishio

  Journal of Wood Chemistry and Technology 39 3 198 - 213 2019年05月04日 [査読有り][通常論文]
  
• Direct electrospinning of cellulose acetate onto polyurethane sheet and effect of its saponification on mechanical properties

  Md. Momotaz Ali, Nutthira Pakkang, Shogo Taira, Keiichi Koda, Koki Itoyama, Yasumitsu Uraki

  Journal of Wood Chemistry and Technology 39 4 282 - 295 2019年 [査読有り][通常論文]
  
• TEMPO-oxidized cellulose nanofiber-reinforced lignin based polyester films as a separator for electric double-layer capacitor

  Shogo Taira, Makoto Kurihara, Keiichi Koda, Kazuki Sugimura, Yoshiyuki Nishio, Yasumitsu Uraki

  Cellulose 26 1 569 - 580 2019年01月 [査読有り][招待有り]
  
• Preparation of water-in-oil microemulsion from the mixtures of castor oil and sunflower oil as makeup remover

  Nutthira Pakkang, Yasumitsu Uraki, Keiichi Koda, Manit Nithitanakul, Ampira Charoensaeng

  Journal of Surfactant and Detergents 21 6 809 - 816 2018年08月 [査読有り][通常論文]
  
• Determination of the absolute molar mass of acetylated eucalyptus kraft lignin by two types of size-exclusion chromatography combined with multi-angle laser light-scattering detectors

  Linping Wang, Yasumitsu Uraki, Keiichi Koda, Aori Gele, Xuesong Zhou, Fangeng Chen

  Holzforschung 73 4 363 - 369 2018年 [査読有り][通常論文]
   

  The molar mass (MM) and polydispersity indices (PDI) of acetylated hardwood kraft lignin (Ac-HWKL) and Ac-HWKL fractions were measured by size-exclusion chromatography with multi-angle laser light scattering (SEC-MALLS). The detectors worked at LL_{658 nm} and LL_{785 nm}. The MM of Ac-HWKL measured at 785 nm was much smaller than that measured at 658 nm. The number-average (Mn) and weight-average (Mw) molar masses of Ac-HWKL determined at 785 nm were approximately 6.2 and 6.5 times larger, respectively, than the values estimated using a conventional calibration curve created with authentic polystyrene standards in tetrahydrofuran (THF). Based on the Mw of Ac-HWKL fractions, the Mark-Houwink-Sakurada equation for Ac-HWKL was established to be [η]/ml g⁻¹=0.320 M^0.24 in THF and [η]/ml g⁻¹=0.142 M^0.26 in dimethyl sulfoxide (DMSO). These results demonstrate that Ac-HWKL has a more compact structure in an organic solvent than polystyrene.
• Ligninolytic activity at 0 °C of fungi on oak leaves under snow cover in a mixed forest in Japan

  Toshizumi Miyamoto, Keiichi Koda, Arata Kawaguchi, Yasumitsu Uraki

  Fungal Microbiology 74 2 322 - 331 2017年08月 [査読有り][通常論文]
   

  Despite the importance of litter decomposition under snow cover in boreal forests and tundra, very little is known regarding the characteristics and functions of litter-decomposing fungi adapted to the cold climate. We investigated the decomposition of oak leaves in a heavy snowfall forest region of Japan. The rate of litter weight loss reached 26.5% during the snow cover period for 7 months and accounted for 64.6% of the annual loss (41.1%). Although no statistically significant lignin loss was detected, decolourization portions of oak leaf litter, which was attributable to the activities of ligninolytic fungi, were observed during snow cover period. This suggests that fungi involved in litter decomposition can produce extracellular enzymes to degrade lignin that remain active at 0 A degrees C. Fungi were isolated from oak leaves collected from the forest floor under the snow layer. One hundred and sixty-six strains were isolated and classified into 33 operational taxonomic units (OTUs) based on culture characteristics and nuclear rDNA internal transcribed spacer (ITS) region sequences. To test the ability to degrade lignin, the production of extracellular phenoloxidases by isolates was quantified at 0 A degrees C. Ten OTUs (9 Ascomycota and 1 Basidiomycota) of fungi exhibited mycelial growth and ligninolytic activity. These results suggested that some litter-decomposing fungi that had the potential to degrade lignin at 0 A degrees C significantly contribute to litter decomposition under snow cover.
• Optimization of simultaneous saccharification and fermentation conditions with amphipathic lignin derivatives for concentrated bioethanol production

  Ningning Cheng, Keiichi Koda, Yutaka Tamai, Yoko Yamamoto, Taichi E. Takasuka, Yasumitsu Uraki

  BIORESOURCE TECHNOLOGY 232 126 - 132 2017年05月 [査読有り][通常論文]
   

  Amphipathic lignin derivatives (A-LDs) prepared from the black liquor of soda pulping of Japanese cedar are strong accelerators for bioethanol production under a fed-batch simultaneous enzymatic saccharification and fermentation (SSF) process. To improve the bioethanol production concentration, conditions such as reaction temperature, stirring program, and A-LDs loadings were optimized in both small scale and large scale fed-batch SSF. The fed-batch SSF in the presence of 3.0 g/L A-LDs at 38 degrees C gave the maximum ethanol production and a high enzyme recovery rate. Furthermore, a jar-fermenter equipped with a powerful mechanical stirrer was designed for 1.5 L-scale fed-batch SSF to achieve rigorous mixing during high substrate loading. Finally, the 1.5 L fed-batch SSF with a substrate loading of 30% (w/v) produced a high ethanol concentration of 87.9 g/L in the presence of A-LDs under optimized conditions. (C) 2017 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
• Association of amphipathic lignin derivatives with cellobiohydrolase groups improves enzymatic saccharification of lignocellulosics

  Yoko Yamamoto, Ningning Cheng, Keiichi Koda, Kiyohiko Igarashi, Yutaka Tamai, Yasumitsu Uraki

  CELLULOSE 24 4 1849 - 1862 2017年04月 [査読有り][通常論文]
   

  Amphipathic lignin derivatives (ALDs), prepared from hardwood acetic acid lignin and softwood soda lignin via coupling with a mono-epoxylated polyethylene glycol, have been reported to improve the enzymatic saccharification efficiency of lignocellulose while maintaining significant residual cellulase activity after saccharification. We previously demonstrated that the effect of ALDs was caused by a direct interaction between ALDs and Cel6A (or CBH II). In this study, a different ALD was prepared from softwood kraft lignin in addition to aforementioned ALDs. The interactions between all the ALDs and the enzymes other than Cel6A, such as Cel7A and Cel7B, in a cellulase cocktail were investigated using surface plasmon resonance. The kraft lignin-based ALD showed the highest residual cellulase activity among all ALDs and an improved cellulolytic enzyme efficiency similar to those of the other ALDs. All ALDs were found to directly associate with major enzymes in the cellulase cocktail, Cel6A and Cel7A (or CBH I), but not with Cel7B (or EG I). In addition, the ALDs showed a much higher affinity to amino groups than to hydroxy and carboxy groups. In contrast, polyethylene glycol (molecular mass 4000 Da), one part of the ALD and a previously reported enzymatic saccharification enhancer, did not adsorb onto any enzymes in the cellulase cocktail or the amino group. Size exclusion chromatography demonstrated that the ALDs formed self-aggregates in both water and chloroform; the formation process in the latter was especially unique. Therefore, we conclude that the high residual cellulase activity is attributed to the direct association of ALD aggregates with the CBH group.
• Preparation of electric double layer capacitors (EDLCs) from two types of electrospun lignin fibers

  Xiangyu You, Junlei Duan, Keiichi Koda, Tatsuhiko Yamada, Yasumitsu Uraki

  HOLZFORSCHUNG 70 7 661 - 671 2016年07月 [査読有り][通常論文]
   

  Electrodes has been prepared for application in an electric double layer capacitor (EDLC) based on polyethylene glycol lignin (PEGL) and soda lignin (SL) derived from cedar wood. Fibers with a diameter of 23 mu m were prepared by direct melt electrospinning of PEGL. Much finer fibers of 3.6 mu m diameter were obtained by dry electrospinning of 70% PEGL in a dimethyl formamide (DMF) solution at 145 degrees C. The dry electrospinning of SL alone in an alkaline aqueous solution was not achievable, but this was possible of a mixture of SL and polyethylene glycol (M-w = 500 000) at a ratio of 99/1, which resulted in thin SL fibers with a diameter of 0.85 mu m. These fibers were converted into activated carbon fibers (ACFs) by thermostabilization, carbonization, and steam activation. The specific Brunauer, Emmett and Teller (BET) surface areas of the resulting PEGL-ACFs and SL-ACFs were 1880 m(2) g(-1) and 1411 m(2) g(-1), respectively. PEGL-ACFs electrodes with an organic electrolyte exhibited an impedance of 1.6 Omega and a specific capacitance of 92.6 F g(-1) at a scan rate of 1 A g(-1), and the SL-ACFs electrodes had an impedance and specific capacitance of 4.5 Omega and 55.6 F g(-1), respectively.
• Preparation of High-Performance Internal Tandem Electric Double-Layer Capacitors (IT-EDLCs) from Melt-Spun Lignin Fibers

  Xiangyu You, Keiichi Koda, Tatsuhiko Yamada, Yasumitsu Uraki

  JOURNAL OF WOOD CHEMISTRY AND TECHNOLOGY 36 6 418 - 431 2016年 [査読有り][通常論文]
   

  Activated carbon fibers (ACFs) with large surface area were easily prepared from melt-spun fibers of polyethylene glycol lignin (PEGL). To fabricate electric double-layer capacitors (EDLCs) with a wide potential window and a high energy density in an EDLC package, electrodes (mainly composed of ACFs) were internally laminated and connected in series, in parallel, or in a series/parallel combination. Such resultant EDLCs are termed internal tandem (IT) EDLCs. As expected, the potential window was expanded by the series connection, and the capacitance was increased by the parallel connection. As a result, the energy density in the parallel-connected EDLC was remarkably increased by 66% (16.6 Wh kg(-1)) compared with that of a single-cell EDLC. The EDLC with the combination connection showed both advantages. Thus, based on the package weight, the electrochemical performance of the EDLCs was remarkably improved by the IT-type lamination of electrodes.
• Preparation of electrode for electric double layer capacitor from electrospun lignin fibers

  Xiangyu You, Keiichi Koda, Tatsuhiko Yamada, Yasumitsu Uraki

  HOLZFORSCHUNG 69 9 1097 - 1106 2015年11月 [査読有り][通常論文]
   

  Lignin-based activated carbon fibers (ACFs) were prepared by electrospinning of hardwood acetic acid lignin (HW-AAL) solution followed by thermostabilization, carbonization, and steam activation. The thermostabilization process was able to be remarkably shortened from 38 h to 3 h with hexamethylenetetramine (hexamine) in binary solvents, AcOH/CCl4 (8/2), when compared with conventional thermostabilization processes. The resultant ACFs possessed higher specific surface area (2185 m(2) g(-1)) than those from commercial activated carbon and electrospun lignin fibers without hexamine. These ACFs also exhibited good electrical capacitance (133.3 F g(-1) at a current density of 1 A g(-1)) as electrodes of electric double layer capacitor (EDLC) are efficient not only due to their large surfaces area but also due to their porous structure with well-developed micropores (diameter: 0.5-1.3 nm). High energy density and power density of this EDLC (42 Wh kg(-1) and 91 kW kg(-1), respectively) were also achieved.
• Dehydrogenative Polymerization of Coniferyl Alcohol in Artificial Polysaccharides Matrices: Effects of Xylan on the Polymerization

  Qiang Li, Keiichi Koda, Arata Yoshinaga, Keiji Takabe, Masatsugu Shimomura, Yuji Hirai, Yutaka Tamai, Yasumitsu Uraki

  JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 63 18 4613 - 4620 2015年05月 [査読有り][通常論文]
   

  To elucidate the influence of wood polysaccharide components on lignin formation in vitro, models for polysaccharide matrix in wood secondary cell wall were fabricated from two types of bacterial cellulosic films, flat film (FBC) and honeycomb-patterned film (HPBC), as basic frameworks by depositing xylan onto the films. An endwise type of dehydrogenative polymerization, Zutropfverfahren, of coniferyl alcohol was attempted in the films with/without xylan. The resultant dehydrogenation polymer (DHP) was generated inside and outside xylan-deposited films, whereas DHP was deposited only outside the films without xylan. The amount of the generated DHP in the xylan-deposited films was larger than that in the films without xylan. The frequency of 8-O-4' interunitary linkage in DHP was also increased by the xylan deposition. These results suggest that xylan acts as a scaffold for DHP deposition in polysaccharides matrix and as a structure regulator for the formation of the 8-O-4' linkage. In addition, mechanical properties, i.e., tensile strength and modulus of elasticity (MOE), of both cellulosic films were found to be augmented by the deposition of xylan and DHP. Especially, DHP deposition remarkably enhanced MOE. Such effects of xylan on DHP formation and augmentation of mechanical strength were clearly observed for HPBC, revealing that HPBC is a promising framework model to investigate wood cell wall formation in vitro.
• Amphipathic lignin derivatives for enzymatic saccharification and fermentation of lignocellulosics

  Yoko Yamamoto, Ningning Cheng, Kiyohiko Igarashi, Keiichi Koda, Yasumitsu Uraki

  ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY 249 2015年03月 [査読有り][通常論文]
  
• Amphipathic lignin derivatives to accelerate simultaneous saccharification and fermentation of unbleached softwood pulp for bioethanol production

  Ningning Cheng, Yoko Yamamoto, Keiichi Koda, Yutaka Tamai, Yasumitsu Uraki

  BIORESOURCE TECHNOLOGY 173 104 - 109 2014年12月 [査読有り][通常論文]
   

  Amphipathic lignin derivatives (A-LDs) were already demonstrated to improve enzymatic saccharification of lignocellulose. Based on this knowledge, two kinds of A-LDs prepared from black liquor of soda pulping of Japanese cedar were applied to a fed-batch simultaneous saccharification and fermentation (SSF) process for unbleached soda pulp of Japanese cedar to produce bioethanol. Both lignin derivatives slightly accelerated yeast fermentation of glucose but not inhibited it. In addition, ethanol yields based on the theoretical maximum ethanol production in the fed-batch SSF process was increased from 49% without A-LDs to 64% in the presence of A-LDs. (C) 2014 Elsevier Ltd. All rights reserved.
• Enzymatic Saccharification of Soda Pulp from Sago Starch Waste Using Sago Lignin-Based Amphipathic Derivatives

  Ina Winarni, Keiichi Koda, Totok K. Waluyo, Gustan Pari, Yasumitsu Uraki

  JOURNAL OF WOOD CHEMISTRY AND TECHNOLOGY 34 3 157 - 168 2014年07月 [査読有り][通常論文]
   

  The aim of this research is to develop an enzymatic saccharification process of sago starch waste, with a small charge of cellulase. The waste contained a significant amount of residual starch, which was recovered as glucose by mild acid hydrolysis. The starch-free residue was subjected to soda-anthraquinone pulping to yield soda pulp and soda lignin. The lignin was converted to amphipathic lignin derivatives by the reaction with epoxylated polyethylene glycol analogues. The pulp was hydrolyzed with cellulase (Genencor GC220), with the amphipathic derivatives, to yield glucose. The lignin derivative-assisted, enzymatic saccharification was repeatedly conducted by reusing cellulase recovered by ultrafiltration from saccharification media. Saccharification efficiency with the derivatives was maintained at a high level even after the fourth run of saccharification, while the efficiency was remarkably decreased by repeated use of cellulase without additive. Thus, the amphipathic sago lignin derivatives enabled repeated use of cellulase for saccharification of sago starch waste.
• Improvement of Mechanical Properties of Softwood Lignin-Based Carbon Fibers

  Jian Lin, Keiichi Koda, Satoshi Kubo, Tatsuhiko Yamada, Makiko Enoki, Yasumitsu Uraki

  JOURNAL OF WOOD CHEMISTRY AND TECHNOLOGY 34 2 111 - 121 2014年06月 [査読有り][通常論文]
   

  PEG-lignin fibers obtained by a solvolysis pulping of Japanese cedar with polyethylene glycol (PEG) 400 were successfully converted into defective-free, infusible fibers as a precursor for carbon fibers (CFs) by chemical curing followed by oxidative thermostabilization. The curing was performed by immersing PEG-lignin fibers in an aqueous mixed solution of hexamethylenetetramine (60g/L) and hydrochloric acid (3M) at 85 degrees C for 1h, resulting in the formation of crosslinkages between lignin molecules through methylene groups. These cured fibers were completely thermostabilized upon heating up to 250 degrees C at a heating rate of 2 degrees C/min under an air atmosphere. Finally, the thermostabilized fibers were carbonized to yield CFs, which showed about 1.5times the tensile strength of our CFs previously prepared.
• Preparation of Novel Lignin-Based Cement Dispersants from Isolated Lignins

  Tomohiro Aso, Keiichi Koda, Satoshi Kubo, Tatsuhiko Yamada, Isamu Nakajima, Yasumitsu Uraki

  JOURNAL OF WOOD CHEMISTRY AND TECHNOLOGY 33 4 286 - 298 2013年12月 [査読有り][通常論文]
   

  Lignin-based amphiphiles were prepared from the waste liquors of softwood and hardwood kraft pulpings (SKLliq and HKLliq, respectively) and their isolated lignins (SKL and HKL, respectively) by a reaction with several epoxylated polyethylene glycol analogues: polyethylene glycol diglycidylether (PEGDE), its monoglycidyl ether (EPEG), and dodecyloxypolyethylene glycol glycidyl ether (DAEO). The effect of these amphiphiles on cement dispersity was examined at 6 degrees C and 20 degrees C. Generally, only half the amount of EPEG- and PEGDE-series (e.g., 0.4%) was required to achieve the same cement dispersibility (e.g., p value of 2) compared to lignosulfonate (LS) (e.g., 0.8%). DAEO-lignin derivatives with the highest surface activity did not show cement dispersibility, suggesting no correlation between cement dispersibility and surface activity of the amphiphiles. Thus, together with the test of bending strength, it was found that the amphiphiles prepared from isolated lignins and EPEG were promising cement dispersants, which were available even in the wintertime without losing mechanical strength.
• Improvement of Enzymatic Saccharification of Unbleached Cedar Pulp with Amphipathic Lignin Derivatives

  Ina Winarni, Chihiro Oikawa, Tatsuhiko Yamada, Kiyohiko Igarashi, Keiichi Koda, Yasumitsu Uraki

  BIORESOURCES 8 2 2195 - 2208 2013年 [査読有り][通常論文]
   

  Synthesized amphipathic lignin derivatives comprised of acidic acid lignin (AL) with poly(ethylene glycol) diglycidyl ether (PEGDE), ethoxy-(2-hydroxy)-propoxy-poly(ethylene glycol) glycidyl ether (EPEG) or dodecyloxy-poly(ethylene glycol) glycidyl ether (DAEO) were added before the enzymatic saccharification of unbleached cedar pulp along with two commercially available cellulases, Meicelase and Genencor GC220. At the same filter paper unit (FPU) dosage, GC220 showed higher sugar yield than Meicelase. The difference was attributed to the composition of processive and non-processive endoglucanase activities per FPU; GC220 had higher such activities than Meicelase. The sugar yield was significantly improved by the addition of the lignin derivatives. In addition, residual activities after the saccharification were maintained at the higher level by their addition than with polyethylene glycol (PEG) 4000. In particular, EPEG-AL yielded the complete recovery of cellulase activity when using 20 FPU/g of substrate. It was found that the lignin derivatives were directly associated with Cel6A, one of cellulase components, whereas PEG 4000 was not. Thus, it is evident that the lignin derivatives are promising agents to improve the enzymatic saccharification of cellulase.
• Thermal Mobility of beta-O-4-Type Artificial Lignin

  Yasumitsu Uraki, Yusuke Sugiyama, Keiichi Koda, Satoshi Kubo, Takao Kishimoto, John F. Kadla

  BIOMACROMOLECULES 13 3 867 - 872 2012年03月 [査読有り][通常論文]
   

  Several lignin model polymers and their derivatives comprised exclusively of beta-O-4 or 8-O-4' interunitary linkages were synthesized to better understand the relation between the thermal mobility of lignin, in particular, thermal fusibility and its chemical structure; an area of critical importance with respect to the biorefining of woody biomass and the future forest products industry. The phenylethane (C6-C2)-type lignin model (polymer 1) exhibited thermal fusibility, transforming into the rubbery/liquid phase upon exposure to increasing temperature, whereas the phenylpropane (C6-C3)-type model (polymer 2) did not, forming a char at higher temperature. However, modifying the C gamma or 9-carbon in polymer 2 to the corresponding ethyl ester or acetate derivative imparted thermal fusibility into this previously infusible polymer. FT-IR analyses confirmed differences in hydrogen bonding between the two model lignins. Both polymers had weak intramolecular hydrogen bonds, but polymer 2 exhibited stronger intermolecular hydrogen bonding involving the C gamma-hydroxyl group. This intermolecular interaction is responsible for suppressing the thermal mobility of the C6-C3-type model, resulting in the observed infusibility and charring at high temperatures. In fact, the C gamma-hydroxyl group and the corresponding intermolecular hydrogen bonding interactions likely play a dominant role in the infusibility of most native lignins.
• CHEMICAL THERMOSTABILIZATION FOR THE PREPARATION OF CARBON FIBERS FROM SOFTWOOD LIGNIN

  Jian Lin, Satoshi Kubo, Tatsuhiko Yamada, Keiichi Koda, Yasumitsu Uraki

  BIORESOURCES 7 4 5634 - 5646 2012年 [査読有り][通常論文]
   

  A thermally fusible softwood lignin was directly isolated by a solvolysis of cedar wood chips with a mixture of polyethylene glycol 400 (PEG 400) and sulfuric acid. Its fusibility was found to be due to a PEG moiety introduced into the lignin by the solvolysis. The lignin was easily formed into fibers by melt-spinning at temperatures ranging from 145 to 172 degrees C without any modification. The lignin fibers could be converted into infusible fibers as a precursor for carbon fibers (CFs) by conventional oxidative thermal stabilization processing in air or a stream of oxygen for 2 days. We found that the infusible fibers resulted from the partial cleavage of the PEG moiety from the lignin fibers after treatment with 6 M hydrochloric acid at 100 degrees C for 2 h. The infusible fibers were converted into CFs with a tensile strength of 450 MPa by carbonization at 1000 degrees C under a N-2 stream.
• Novel Functions of Non-Ionic, Amphiphilic Lignin Derivatives

  Yasumitsu Uraki, Keiichi Koda, Tatsuhiko Yamada, Chihiro Oikawa, Tomohiro Aso

  FUNCTIONAL MATERIALS FROM RENEWABLE SOURCES 1107 243 - + 2012年 [査読有り][通常論文]
   

  Technical lignins including water-insoluble isolated lignins were easily converted to water-soluble derivatives by the reaction with several types of epoxidized polyethylene glycol derivatives. The resulting lignin-based derivatives were soluble in water and organic solvents, thus having amphiphilic property. We found novel functions of the amphiphiles, such as the uses as cellulase-aid agent and cement dispersant in addition to the surfactant action. This article reviews the functions in relation to the development of biorefining processes for Japanese woody biomass.
• PREPARATION OF NOVEL LIGNIN-BASED CEMENT DISPERSANT VIA AMPHIPHILIC DERIVATIZATION OF TECHNICAL LIGNIN

  Tomohiro Aso, Keiichi Koda, Satoshi Kubo, Tatsuhiko Yamada, Isamu Nakajima, Yasumitsu Uraki

  PROCEEDING OF THE 4TH INTERNATIONAL CONFERENCE ON PULPING, PAPERMAKING AND BIOTECHNOLOGY (ICPPB '12), VOLS. I AND II 90 - 93 2012年 [査読有り][通常論文]
   

  Novel, non-ionic type cement dispersants were prepared from various isolated lignins, softwood and hardwood haft lignins, black liquors from softwood and hardwood haft pulpings, and softwood soda lignin by the reaction with several epoxylated polyethylene glycol (PEG) derivatives, polyethylene glycol diglycidylether (PEGDE), its monoglycidyl ether (EPEG) and dodecyloxypolyethylene glycol glycidyl ether (DAEO). Cement dispersibility of the resultant lignin-based derivatives were examined at 6 C and 20 degrees C. EPEG- and PEGDE-based lignin derivatives gave higher dispersity of cement than lignosulfonate (LS) at both temperatures. Among all the lignin derivatives, EPEG-softwood haft lignin showed the highest cement dispersibility. On the other hand, DAEO-based derivatives did not exhibit cement dispersibility in spite of the fact that it showed the highest surface activity. Thus, it was found that there was no correlation between cement dispersibility and surface activity of lignin-based amphiphiles.
• PREPARATION OF CARBON FIBERS FROM SOFTWOOD LIGNIN THROUGH CHEMICAL THERMOSTABILIZATION

  Jian Lin, Satoshi Kubo, Tatsuhiko Yamada, Keiichi Koda, Yasumitsu Uraki

  PROCEEDING OF THE 4TH INTERNATIONAL CONFERENCE ON PULPING, PAPERMAKING AND BIOTECHNOLOGY (ICPPB '12), VOLS. I AND II 860 - 863 2012年 [査読有り][通常論文]
   

  Solvolysis of cedar Wood with a mixture of polyethylene glycol 400 (PEG 400) and sulfuric acid gave thermally fusible softwood lignin (PEG-lignin), which was easily spun into fibers by melt-spinning at a temperature range of 145 to 172 degrees C without any modification. It took more than 2 days to convert the fibers into thermostabilized ones by the oxidation under air or oxygen atmosphere; that is termed as "conventional thermostabilization". As a shortening process, we developed "chemical thermostabilization"; the PEG-lignin fibers were converted into infusible fibers as a precursor for carbon fibers (CFs) by immersing at 100 degrees C for 2 h. CFs with a tensile strength of 450 MPa were obtained by carbonization at 1000 degrees C under a N-2 stream. The resultant CFs were, in turn, readily converted to activated CFs with large specific surface area of 3060 m(2)/g by the steam activation. This effective activation was attributed to defects generated by chemical thermostabilization, from which the activation proceeded into inside of fibers.
• Fabrication of honeycomb-patterned cellulose material that mimics wood cell wall formation processes

  Yasumitsu Uraki, Yutaka Tamai, Takuro Hirai, Keiichi Koda, Hiroshi Yabu, Masatsugu Shimomura

  MATERIALS SCIENCE & ENGINEERING C-MATERIALS FOR BIOLOGICAL APPLICATIONS 31 6 1201 - 1208 2011年08月 [査読有り][通常論文]
   

  Wood cell wall, composed of polysaccharides (cellulose and hemicelluloses) and an aromatic polymer (lignin), exhibits a honeycomb-like alignment. We have been making attempts to fabricate cellulose-based materials to reconstruct these wood components artificially, mimicking their formation processes. Those attempts are aiming not only at better understanding of the significance and the function of each wood component, but also at providing a novel, biomass-based polymer material with functionality. This article outlines a protocol to prepare honeycomb-patterned cellulose films with two different polymorphisms, carrying different pore sizes, as a basic framework of the artificial cell wall structure. It also illustrates the effect of the presence of hemicellulose and lignin on the physical property of the honeycomb-patterned cellulose films, when they were adsorbed onto the films. (C) 2010 Elsevier B.V. All rights reserved.
• Chemicals from lignin based on thermal fusibility and amphiphilicity

  Keiichi Koda, Satoshi Kubo, Yasumitsu Uraki

  ACS Symposium Series 1067 261 - 277 2011年 [査読有り][通常論文]
   

  Development of low-cost, value-added bio-materials from technical lignins is essential in terms of complete utilization of woody biomass components (biorefining). A simply designed chemical modification may provide technical lignins with some unique properties: thermal fusibility, thermal moldability, amphiphilicity, and miscibility with synthetic polymers. Here, the fundamental characteristics of technical lignins are first overviewed. Second, recent progress in chemical modification of technical lignins for industrial application is reviewed. Finally, newly developed lignin-containing materials with functionality are discussed. © 2011 American Chemical Society.
• UTILIZATION OF AMPHIPHILIC LIGNIN DERIVATIVES

  Yasumitsu Uraki, Harumi Homma, Chihiro Oikawa, Tomohiro Aso, Keiichi Koda

  16TH INTERNATIONAL SYMPOSIUM ON WOOD, FIBER AND PULPING CHEMISTRY, PROCEEDINGS, VOLS I & II 165 - 169 2011年 [査読有り][通常論文]
   

  We have developed a conversion method of isolated lignins to amphiphiles with three polyethylene glycol (PEG) analogues bearing epoxy groups, termed as PEGDE, EPEG and DAEO. These lignin-based amphiphiles showed significant surface activity. DAEO-derivative revealed the highest activity as comparable to Triton X-100, commercially available nonionic surfactant. We found another useful application of these lignin-based amphiphiles in addition to its utilization as a surfactant. When the amphipiles were added to pulp suspension in a buffered solution together with cellulase, the enzymatic saccharification yields were significantly improved and residual cellulase activity after the saccharification was maintained at higher levels than that without the amphiphiles. EPEG-derivative indicated the highest residual activity. These results suggest that the lignin-based amphiphiles can be used as a cellulase-aid agent, leading to reduction of saccharification cost. EPEG and DAEO-derivatives are also found to act as a cement admixture, which was known to reduce the amount of water used for well dispersing cement, and was very often produced from lignosulfates. These derivatives showed a superior dispersibility for cement to lignosulfates in spite of the fact that it is a nonionic surfactant. In addition, such the derivatives could be prepared directly from black liquor of kraft pulping by one step reaction without isolation of kraft lignin from the black liquor. Thus, a new type cement dispersant or admixture, as well as cellulase-aid agent, was readily prepared from isolated lignins, such as kraft lignin and organosolv lignins, by our developed modification method-with PEG analogues.
• 両親媒性リグニン誘導体を用いたオイルパーム空果房およびスギパルプの酵素糖化の改善

  テウク・ベウナ・バルダント, 及川千皓, 野尻昌信, 幸田圭一, ヤニ・スディヤニ, 山田竜彦, 浦木康光

  木材学会誌 56 6 420 - 426 2010年 [査読有り][通常論文]
   

  A huge amount of lignocellulosic wastes are disposed on an industrial scale as unused biomass both in Japan and in Southeast Asia : including forest thinnings of Japanese cedar wood and empty fruit bunches (EFB) of the oil palm tree. Supposing the production of platform compounds from such unused biomass through enzymatic saccharification, we have developed a cellulase-aid agent by the conversion of acetic acid lignin into an amphiphilic derivative (PE-AL). EFB pulps with 1096 and 12% residual lignin and cedar pulp with 11% residual lignin were prepared by kraft and soda pulping processes, respectively, as a pretreatment of enzymatic saccharification. An addition of PE-AL significantly improved the saccharification yield of the cedar pulp, while it improved those of EFB pulps dramatically. After the enzymatic saccharification, the cellulase activity remained in the presence of PEAL, although no activity was detected in the absence of PE-AL.
• Conversion of Technical Lignins to Amphiphilic Derivatives with High Surface Activity

  Harumi Homma, Satoshi Kubo, Tatsuhiko Yamada, Keiichi Koda, Yasuyuki Matsushita, Yasumitsu Uraki

  JOURNAL OF WOOD CHEMISTRY AND TECHNOLOGY 30 2 164 - 174 2010年 [査読有り][通常論文]
   

  To make use of technical lignins as a nonionic polymeric surfactant, we have already reported the modification of acetic acid lignin (AL) to amphiphilic derivatives by polyoxyethylation using two types of polyethylene glycol (PEG) with diglycidyl (PEGDE) and monoglycidyl (EPEG) groups.[1] Kraft lignin (KL) was converted to amphiphiles in a similar manner. The resultant KL derivatives also indicated high surface activity. Polyethylene glycol with long alkyl chain was introduced to AL, KL, and lignosulfonate (LS) to prepare surfactants of high performance, using dodecyloxy-polyethylene glycol glycidyl ether (DAEO). The resultant DAEO-derivatives showed lower critical micelle concentration by 2-4 orders of magnitude than the corresponding PEGDE- and EPEG-derivatives. The DAEO-derivatives from LS showed better dispersibility for gypsum paste, one of cement components, than LS.
• Wood density variations of tropical wood species: Implications to the physical and chemical properties of sawdust

  Rizki Maharani, Yutaka Tamai, Keiichi Koda, Yasuo Kojima, Minoru Terazawa

  Wood Research Journal (Journal of Indonesian Wood Research Society) 1 1 34 - 39 2010年 [査読無し][通常論文]
  
• FUSIBILITY OF ISOLATED LIGNINS

  Yasumitsu Uraki, Keiichi Koda, Takao Kishimoto, Satoshi Kubo

  RESEARCH PROGRESS IN PAPER INDUSTRY AND BIOREFINERY (4TH ISETPP), VOLS 1-3 315 - 318 2010年 [査読有り][通常論文]
   

  We have first found that hardwood acetic acid lignin (HAL), one of organosolv lignins, had fusibility, which had never reported for other isolated lignins. HAL can be transformed into fibers by melt spinning, and then carbon fibers and activated carbon fibers by heat treatments. Kubo and his colleagues successfully prepared fibers by melt spinning from a hardwood organosolv lignin and a hardwood kraft lignin. The moldability of these lignins was attributed to fusibility of isolated lignins. However, the relationship between the presence of beta-O-4 bond, the major interunitary linkage of lignin, and its fusibility was not elucidated. We investigated the relationship, using artificially synthesized lignin polymers consisting exclusively of beta-O-4 bond having phenylpropane guaiacyl moiety. As a result, the model polymer was not transformed into a molten state, although it showed a glass transition. It was found, from FT-IR measurement with variable temperature mode, that its molecular motion was suppressed by the formation of intermolecular hydrogen bonding of a primary hydroxyl group at gamma-position. Therefore, the fusibility of organosolv lignins was attributed to the modification of primary hydroxyl group with the cooking solvents used for the pulping processes.
• FABRICATION OF ARTIFICIAL WOOD CELL WALL AND ITS APPLICATION

  Yuka Tasaki, Yasumitsu Uraki, Keiichi Koda, Sadaaki Yamamoto, Hiroshi Yabu, Masatsugu Shimomura

  RESEARCH PROGRESS IN PAPER INDUSTRY AND BIOREFINERY (4TH ISETPP), VOLS 1-3 1465 - 1468 2010年 [査読有り][通常論文]
   

  Honeycomb-patterned cellulose films were prepared, and coated with arabinogalactan, a larch hemicellulose. An application of the hemicellulose-coated, honeycomb-patterned cellulose films was proposed. First, we attempted to control the pore sizes of honeycomb-patterned bacterial cellulose (HPBC) films. HPBC films with pore sizes of 10, 15, and 20 mu m were successfully fabricated, but the one with a pore size of 5 mu m was not. Second, we evaluated the applicability of the arabinogalactan-coated, honeycomb-patterned regenerated cellulose (HPRC) films to scaffolds for hepatocyte culture. It was observed that the arabinogalactan-coated HPRC films had a unique adhesion of hepatocyte: formation of spheroid-like structure and insertion of individual globular cells each in the honeycomb pores.
• IMPROVEMENT OF CELLULASE ACTIVITY WITH AMPHIPHILIC LIGNIN DERIVATIVE

  Chihiro Oikawa, Keiichi Koda, Yasumitsu Uraki, Masanobu Nojiri, Tatsuhiko Yamada, Kiyohiko Igarashi

  RESEARCH PROGRESS IN PAPER INDUSTRY AND BIOREFINERY (4TH ISETPP), VOLS 1-3 1306 - 1309 2010年 [査読有り][通常論文]
   

  An effective cellulase-aid agent has to be developed to establish an efficient saccharification system for bioethanol production from huge piles of unused, lignocellulosic biomass. We have successfully developed some types of lignin derivatives that enhance the efficiency of enzymatic hydrolysis of unbleached pulp with cellulase and help to maintain its original activity after repeated use. These cellulase-aid agents were prepared by the conversion of acetic acid lignin into amphiphilic derivatives with polyethylene glycol-related compounds.
• Evaluation of Reaction Efficiency of Thioacidolysis for Cleavage of -O-4 Interunitary Linkages by Using -O-4 Type Artificial Lignin Polymer

  Yoshie Kanazawa, Takao Kishimoto, Keiichi Koda, Kazuhiko Fukushima, Yasumitsu Uraki

  JOURNAL OF WOOD CHEMISTRY AND TECHNOLOGY 29 2 178 - 190 2009年 [査読有り][通常論文]
   

  Dimeric lignin model compounds with non-phenolic and phenolic moieties and a -O-4 type artificial lignin polymer were subjected to thioacidolysis to evaluate the reaction efficiency of thioacidolysis for cleavage of -O-4 interunitary linkage. The obtained yields of thioethylated monomeric products from the dimeric lignin model compounds reached nearly 100% under the conventional condition, whereas that from the artificial lignin polymer was as low as 74%. Neither prolonged reaction time nor increased concentration of ethanethiol (the thioacidolysis reagent) enhanced the resulting monomer yields from the polymer (69-79%). Thioacidolysis of the lignin model compounds followed by HPSEC analysis also showed the dimeric model compounds were degraded almost quantitatively, but that the artificial lignin polymer was not. Thioacidolysis followed by desulfurization gave at least one dimeric product resulting from incomplete -O-4 cleavage at significant yield. These results suggested the conventional thioacidolysis could not achieve quantitative cleavage of -O-4 linkages in lignin macromolecules.
• Reactivity of beta-O-4 Determination Methods to Artificial beta-O-4 Lignin Polymers

  Yoshie Kanazawa, Takao Kishimoto, Keiichi Koda, Kazuhiko Fukushima, Yasumitsu Uraki

  PROCEEDINGS OF INTERNATIONAL CONFERENCE ON PULPING, PAPERMAKING AND BIOTECHNOLOGY 2008: ICPPB '08, VOL I 659 - 663 2008年 [査読有り][通常論文]
   

  Non-phenolic and phenolic lignin-dimeric model compounds and a beta-O-4 type artificial lignin polymer have been subjected to thioacidolysis with ethanethiol and boron tribromide etherate to evaluate the reaction efficiency of thioacidolysis for cleavage of beta-O-4 linkage. The obtained yields of thioacidolysis products from dimeric model compounds reached nearly 100% under conventional thioacidolysis conditions, whereas those for the artificial lignin polymer were only at around 70%. Neither prolonged reaction time nor increasing In the concentration of the thioacidolysis reagent enhanced the yields of thioacidolysis products. Thioacidolysis of the lignin models followed by high performance size exclusion chromatographic (HPSEC) analysis also showed that dimeric model compound was degraded almost quantitatively, but artificial lignin polymer was not. These results suggested that conventional thioacidolysis could not achieve quantitative cleavage beta-O-4 linkages in lignin macromolecules.
• 三倍体毛白杨KP法蒸煮中木素结构的变化

  刘 玉, 詹 怀宇, 陈 嘉川, Keiichi Koda, Dimitris Argyropoulos

  中国造纸学报 21 4 14 - 18 2006年 [査読有り][通常論文]
  
• Interference of carbohydrates in the determination of the methoxyl content of lignin in woody samples

  H Goto, K Koda, GL Tong, Y Matsumoto, G Meshitsuka

  JOURNAL OF WOOD CHEMISTRY AND TECHNOLOGY 26 1 81 - 93 2006年 [査読有り][通常論文]
   

  To evaluate the effect of the presence of carbohydrates on the determination of the methoxyl content of lignin, the mechanism of acid-catalyzed reaction of lignin methoxyl groups with iodide ion to form methyl iodide was evaluated using carbohydrate and lignin model compounds. Not only the iodide concentration but also the acid concentration was found to significantly affect the rate of formation of methyl iodide. This fact and Hammett plots of the relative reaction rates observed for several model compounds suggest an S(N)2cA reaction mechanism for methyl iodide formation. Carbohydrates interfered with the rate of formation of methyl iodide, probably by acting as Lewis bases. Interestingly, the study also revealed that a certain amount of methyl iodide could arise from carbohydrates even when the carbohydrates did not contain methoxyl groups as potential precursors to methyl iodide. These sources of error were significant when methoxyl content was determined for samples with low lignin content.
• Formation of methyl iodide from methoxyl-free compounds by hydriodic acid treatment

  H Goto, K Koda, GL Tong, Y Matsumoto, G Meshitsuka

  JOURNAL OF WOOD SCIENCE 51 3 312 - 314 2005年 [査読有り][通常論文]
  
• Molecular weight-functional group relations in softwood residual kraft lignins

  K Koda, AR Gaspar, L Yu, DS Argyropoulos

  HOLZFORSCHUNG 59 6 612 - 619 2005年 [査読有り][通常論文]
   

  An integrated picture of the distribution of functional groups should be provided as a function of molecular size within residual kraft lignins. With this goal we developed a reliable and reproducible method for determination of the molecular weight and molecular weight distribution of residual kraft lignins (RKLs) over the whole delignification range. In general, our data indicate that for reliable measurement of the molecular weight and its distribution of residual lignin in pulps, the lignin-carbohydrate bonds have to be cleaved prior to size exclusion chromatography. The recently developed method for isolating residual lignins, which involves cellulolytic treatment followed by a mild acid hydrolysis step, was found to be the most suitable approach to achieve this. The molecular weight and polydispersity of all RKLs decreased as a function of delignification. As anticipated, the observed decrease in molecular weight was clearly reflected in the concomitantly decreasing amount of beta-O-4 structural linkages present. Similarly, the total phenolic hydroxyl content increased as the molecular weight of the RKLs decreased during kraft pulping. Despite the smaller size of the lignin remaining on the kraft fiber at the end of delignification, the preponderance of condensed phenolic structures within these lignins offers an explanation for delignification problems during bleaching.
• Quantitative H-1 NMR analysis of alkaline polysulfide solutions

  DS Argyropoulos, YH Hou, R Ganesaratnam, DN Harpp, K Koda

  HOLZFORSCHUNG 59 2 124 - 131 2005年 [査読有り][通常論文]
   

  A novel analytical protocol for the absolute determination of the various polysulfide species present in alkaline aqueous media was developed. The method is comprised of alkylating polysulfide ions with dimethyl sulfate, followed by quantitative proton NMR spectroscopy using 1,3,5-tributyl benzene as the internal standard. In order to arrive at a quantitative acquisition protocol, a number of variables were examined in detail for their effect on the alkylation reaction, including the presence of oxygen, the amount of dimethyl sulfate and sodium hydroxide, and the various modes of adding the alkylating reagent to the reaction mixture. Most of these variables were found to play a role in determining the quantitative reliability of the procedure. Consequently, a method is described that can be used for the efficient and reliable quantitative detection of polysulfide ions. The protocol developed could be particularly useful in promoting our understanding of the intricate and delicate chemistry of polysulfide equilibria in aqueous alkaline media.
• Mechanisim of methyl iodide formation during the determination reaction of methoxyl group in lignin and wood

  H Goto, K Koda, GL Tong, Y Matsumoto, G Meshitsuka

  2nd International Symposium on Technologies Of Pulping, Papermaking and Biotechnology on Fiber Plants, Proceedings 75 - 79 2004年 [査読有り][通常論文]
   

  In an effort to evaluate the effect of the presence of carbohydrates on the determination of methoxyl content in lignin, an improved method similar to Baker's one was developed. The method employs a closed system for the HI treatment of sample with subsequent G C determination of the product (methyl iodide). Not only the iodide concentration but also the acid concentration wag found to significantly affect the formation rate of methyl iodide. This, and Hammett Plots of the relative reaction rate observed for several model compounds suggest an SN2cA reaction mechanism for methyl iodide formation. As predicted by this mechanism, carbohydrates interfered with the formation rate of methyl iodide, probably acting as Lewis base that consumes protons. Interestingly, our research also revealed that a certain amount of methyl iodide could arise from carbohydrates even when the carbohydrate did not contain a methoxyl group as a precursor of methyl iodide.$ These sources of error were significant when methoxyl content was determined for a sample with low lignin content.
• Oxidative cleavage of lignin aromatics during chlorine bleaching of kraft pulp

  K Koda, H Goto, H Shintani, Y Matsumoto, G Meshitsuka

  JOURNAL OF WOOD SCIENCE 47 5 362 - 367 2001年 [査読有り][通常論文]
   

  Methanol liberation and methoxyl loss during chlorine bleaching of softwood kraft pulp were quantitatively investigated to estimate the degree of structural modification of lignin aromatics. An increase in the chlorine multiple led to enhanced methoxyl loss from lignin;. Our result, using pH-adjusted chlorine water (pH 5.7), by which chlorination under oxidation-favorable conditions was achieved, strongly supported the importance of the oxidation reaction by chlorine during delignification and lignin degradation. It was also suggested that methanol can be produced not only via catalytic hydrolysis by chlorine but via oxidative cleavage of the ether bond as well. The infrared spectrum of chlorolignins suggested that chlorine oxidation can open aromatic rings to muconic acid derivatives without cleaving ether bonding of the methoxyl group. No straight relation: between the methoxyl content and the kappa number of chlorinated pulps was shown, The methoxyl content of bleached kraft pulps subjected to successive chlorination and alkali extraction showed a good relation with the kappa number. This means that almost all the portions of the oxidatively modified lignin structure were successfully removed during these treatments, and the aromatic structures of residual lignin in chlorinated and alkali-extracted pulps were thought to remain intact.
• 脱シリカを抑制したイネワラの酸素・弱アルカリ系パルプ化法に関する研究

  朴 承榮, 幸田圭一, 松本雄二, 飯塚堯介, 飯山賢治

  紙パルプ技術協会誌 54 9 1245 - 1251 JAPAN TECHNICAL ASSOCIATION OF THE PULP AND PAPER INDUSTRY 2000年 [査読有り][通常論文]
   

  イネワラを原料としてパルプ生産を行う上で最も大きな問題となるのが, イネワラ中に多量に含まれるシリカである。イネワラのパルプ化において, シリカを保持しながらも, リグニンをほぼ完全に脱離する技術の開発は, イネワラをパルプ原料として利用する可能性を広げるものであると考えられる。そこで, 脱シリカを極力抑制したイネワラのパルプ化法として, 酸素-亜硫酸塩蒸解及び酸素-アンモニア蒸解の可能性に着目し, この蒸解法によるイネワラのパルプ化において, 脱リグニン, 脱シリカ, 炭水化物収率などの挙動を詳しく検討した。
  水酸化ナトリウムを用いる場合は, 酸素圧下でもそうでない場合でも, シリカがほぼ完全に除去された。これに対して, 酸素-亜硫酸塩蒸解と酸素-アンモニア蒸解では, 脱リグニンが95%まで進行した場合でも, シリカの保持率は非常に高く, 約70%程度であった。一方, 炭水化物収率については, 前者ではカッパー価10のパルプで90%と非常に高いが, 後者では, 74%であり, 対照とした酸素-水酸化ナトリウム蒸解の結果よりも低い値であった。
  中性糖分析の結果から, 酸素-亜硫酸塩蒸解では, グルコースの保持率が非常に高いばかりでなく, 脱リグニンが進行しても, ヘミセルロースに由来する中性糖の保持率もあまり減少しないことがわかった。一方, 酸素-アンモニア蒸解では他の酸素-アルカリ系蒸解に比べ, ヘミセルロース由来の中性糖の保持率が低いばかりでなく, グルコースの保持率もあまり高くないことが明らかになった。
  以上より, 酸素-亜硫酸塩蒸解ではシリカの保持率, 炭水化物収率ともに高いために, 高収率パルプ化が可能であることがわかった。
• Quantitative study on the possible formation of chloroform during chlorine bleaching of kraft pulp

  K Koda, H Shintani, Y Matsumoto, G Meshitsuka

  JOURNAL OF WOOD SCIENCE 46 4 339 - 341 2000年 [査読有り][通常論文]
  
• イネワラのアルカリ系蒸解過程における脱シリカと脱リグニン挙動との速度論的比較

  朴 承榮, 幸田圭一, 松本雄二, 飯塚堯介, 飯山賢治

  紙パルプ技術協会誌 53 11 1492 - 1499 JAPAN TECHNICAL ASSOCIATION OF THE PULP AND PAPER INDUSTRY 1999年 [査読有り][通常論文]
   

  A systematic study on kinetics of delignification and silica removal is necessary for optimization and a control of rice straw pulping process. Delignification and silica removal from four fractions (internode, sheath, blade and ear) of rice straw were kinetically investigated under soda pulping conditions in the temperature ranges from 30 to 70°C and from 100 to 140°C. Both delignification and silica removal by sodium hydroxide treatment were suggested to be a pseudo first order reaction. The delignification progress of rice straw was separated clearly into at least two phases. About 80% delignification was achieved in the first phase even under a mild condition at 80°C under which the degradation reaction of wood lignin was almost impossible to occur. The delignification rates of the internode, sheath and blade are larger than that of ear. It was confirmed that silica removal is a kinetically easier process than delignification under alkali pulping conditions. The rate of silica removal is greater than that of delignification, and the former is easier to increase with increasing temperature. Therefore, it was concluded that complete delignification from rice straw without serious silica removal can not be achieved as long as sodium hydroxide is employed as a cooking reagent. Other components of cell wall (i.e. hemicellulose) had virtually no effect on the kinetic parameters of silica removal.
• Evaluation of the extent of the oxidation reaction during chlorine bleaching of pulp

  K Koda, H Shintani, Y Matsumoto, G Meshitsuka

  JOURNAL OF WOOD SCIENCE 45 2 149 - 153 1999年 [査読有り][通常論文]
   

  A modified method was developed to evaluate how much chlorine is consumed by the oxidation reaction during the chlorine bleaching process. This evaluation is, in principle, based on the sum of chloride produced during the chlorination stage (C-stage) and produced during alkali treatment of both the C-stage effluent and the chlorinated pulp. Results obtained by this method proved that about 50%-75% of chlorine was consumed by the oxidation reaction during chlorine bleaching, depending on the reaction condition of chlorination. Even under a reaction condition that is not favorable to an oxidation reaction (low pH), approximately three electrons were abstracted from one lignin structural unit by chlorine bleaching. This result provides additional evidence for our recent observation that lignin is extensively oxidized during chlorine bleaching even when pure chlorine without any chlorine dioxide substitution was used.
• Resistance of highly chlorinated lignin in pulp toward chlorine oxidation

  H Shintani, K Koda, Y Matsumoto, G Meshitsuka

  ISWPC - 9TH INTERNATIONAL SYMPOSIUM ON WOOD AND PULPING CHEMISTRY - POSTER PRESENTATIONS 1041 - 1044 1997年 [査読有り][通常論文]
   

  Unbleached hardwood kraft pulp and unbleached softwood kraft pulp were chlorinated at various levels of chlorine ratio (0.10-0.23), and were separated to chlorinated pulps and C-stage effluents. The amount of total organic carbon (TOC) and total organic chlorine (TOCl) of C-stage effluents increased with chlorine ratio for both hardwood and softwood kraft pulps. The TOCl/TOC ratios of C-stage effluents were almost constant (0.12) at any chlorine ratio for both hardwood and softwood kraft pulps. The chlorine content of the residual lignin in chlorinated pulp increased with chlorine ratio, and the organic chlorine per carbon of the residual lignin which was estimated roughly by E-stage effluent lignin were quite larger than 0.12 for both pulps (high chlorine ratio). These results indicate that residual lignin were already reacted by substantial amount of chlorine. About 80% of chlorine was chlorination.

MISC

• S1+G型の引張あて材木部繊維におけるリグニンと非セルロース性多糖類、AGPの分布．

  吉永 新, 粟野達也, 幸田圭一, 玉井 裕, 浦木康光, 高部圭司 第69回日本木材学会大会講演要旨集 2019年03月 [査読無し][通常論文]
  
• コニフェリルアルコールの脱水素重合に及ぼすヘミセルロースの効果．

  松尾朱実, 古川貴大, 玉井 裕, 幸田圭一, 浦木康光, 吉永 新, 高部圭司 第68回日本木材学会大会講演要旨集 2018年03月 [査読無し][通常論文]
  
• 樹木組織中での安定同位体標識モノリグノール類の移動～同位体顕微鏡による可視化～

  小川真由, 幸田圭一, 重富顕吾, 坂本直哉, 高部圭司, 吉永 新, 浦木康光 第67回日本木材学会大会講演要旨集 129 -129 2017年03月 [査読無し][通常論文]
  
• 両親媒性リグニン誘導体を用いたリグノセルロースからのバイオエタノール製造

  CHENG Ningning, 山本陽子, 幸田圭一, 浦木康光, 五十嵐圭日子 セルロース学会年次大会講演要旨集 23rd 2016年
• Utilization of wood cell wall components

  Yasumitsu Uraki, Keiichi Koda JOURNAL OF WOOD SCIENCE 61 (5) 447 -454 2015年10月 [査読有り][招待有り]
   

  This article summarizes current utilizations of wood cell wall components in relation to biorefinery of woody biomass as a separation method of its constituents. Especially, utilization of isolated lignins, involving transformation and molding, are demonstrated with respect to productions of carbon fibers and their further functionalization, such as developments of activated carbon fibers and electrodes for second battery and electric double-layer capacitor.
• Honeycomb-patterned cellulose films as a promising tool to investigate deformation of wood cross section and wood cell wall formation

  Yasumitsu Uraki, Qiang Li, Teuku Bardant, Keiichi Koda ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY 249 2015年03月 [査読無し][通常論文]
  
• セルラーゼ活性を増強する両親媒性リグニン誘導体-セルラーゼとの相互作用解析-

  山本陽子, CHENG Ningning, WINARNI Ina, 五十嵐圭日子, 幸田圭一, 浦木康光 セルロース学会年次大会講演要旨集 21st 2014年
• バイオエタノール生産に有用な両親媒性リグニン誘導体

  山本陽子, CHENG Ningning, 幸田圭一, 浦木康光, 五十嵐圭日子 日本木材学会北海道支部講演集(Web) (46) 2014年
• セルラーゼと両親媒性リグニン誘導体との相互作用

  山本陽子, 及川千皓, 幸田圭一, 浦木康光, 五十嵐圭日子 セルロース学会年次大会講演要旨集 20th 2013年
• ウッドバイオリファイナリー 4. パルプ化とその分離成分の利活用

  浦木康光, 幸田圭一 材料 61 (10) 867 -871 2012年10月 [査読有り][通常論文]
  
• 両親媒性リグニン誘導体の秘められた機能とその活用

  浦木康光, 幸田圭一, 山田竜彦 機能材料 32 (2) 42 -47 2012年 [査読無し][招待有り]
  
• Amphiphilic lignin derivatives as cellulase-aid agent and cement admixture

  Yasumitsu Uraki, Chihiro Oikawa, Tomohiro Aso, Keiichi Koda, Tatsuhiko Yamada ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY 241 2011年03月 [査読無し][通常論文]
  
• セルラーゼ活性増強剤となるリグニン誘導体の開発

  及川千皓, イナウィナルニ, 幸田圭一, 浦木康光, 山田竜彦, 野尻昌信, 五十嵐圭日子 高分子学会北海道支部研究発表会講演要旨集 45th 2011年
• 両親媒性リグニン誘導体とセルラーゼ間の相互作用の解明

  及川千皓, WINARNI Ina, 幸田圭一, 浦木康光, 山田竜彦, 野尻昌信, 五十嵐圭日子 セルロース学会年次大会講演要旨集 18th 2011年
• 両親媒性リグニン誘導体とセルラーゼ間の相互作用の解明

  及川千皓, イナウィナルニ, 幸田圭一, 浦木康光, 山田竜彦, 野尻昌信, 五十嵐圭日子 日本木材学会北海道支部講演集(Web) (43) 2011年
• ヘミセルロース吸着ハニカムセルロースフィルムの調製とその肝実質細胞培養基質としての有用性の評価

  田崎裕佳, テウク ベルナバルダント, 浦木康光, 幸田圭一, 藪浩, 下村政嗣 高分子学会北海道支部研究発表会講演要旨集 45th 2011年
• ヘミセルロース吸着ハニカムパターン化セルロースの物性とその応用

  田崎裕佳, BARDANT Teuku Berna, 浦木康光, 幸田圭一, 平井悠司, 藪浩, 下村政嗣 セルロース学会年次大会講演要旨集 18th 2011年
• セルラーゼ活性増強剤となるリグニン誘導体の開発

  及川千皓, 幸田圭一, 浦木康光, 山田竜彦, 野尻昌信, 五十嵐圭日子 セルロース学会年次大会講演要旨集 17th 2010年
• ヘミセルロース吸着ハニカムパターン化セルロースの調製とその応用

  田崎裕佳, 浦木康光, 幸田圭一, 山本貞明, 藪浩, 下村政嗣 セルロース学会年次大会講演要旨集 17th 2010年
• イネワラをパルプ原料として利用するための基礎的技術の開発

  環境科学総合研究所年報 19 125 -133 2000年 [査読無し][通常論文]
  
• Advanced technologies for the pulping of rice straw

  Annual report of interdisiplinary research institute of environmental sciences 19 125 -133 2000年 [査読無し][通常論文]
  

書籍等出版物

• 森林保護学の基礎

  小池, 孝良, 中村, 誠宏, 宮本, 敏澄 (担当:分担執筆範囲:【コラム４・４】ヘミセルロースに含まれる糖類)
  農山漁村文化協会 2021年04月 (ISBN: 9784540122101) 191p p.87
• 植物細胞壁実験法

  石井, 忠, 石水, 毅, 梅澤, 俊明, 加藤, 陽治, 岸本, 崇生, 小西, 照子, 松永, 俊朗 (担当:分担執筆範囲:2.1.3 31P NMRによるリグニン水酸基の定量)
  弘前大学出版会 2016年02月 (ISBN: 9784907192211) xi, 403p p.65-70
• Encyclopedia of polymeric nanomaterials

  Yasumitsu Uraki, Keiichi Koda (担当:分担執筆範囲:Lignin)
  Springer-Verlag, Berlin 2015年 (ISBN: 9783642361999) 2672 pp.1073-1080
• セルロースナノファイバーの調製、分散・複合化と製品応用

  浦木康光, 游 翔宇, 幸田圭一 (担当:分担執筆範囲:エレクトロスピンイング法によるセルロースナノファイバーの調製とその特性)
  ㈱技術情報協会 2015年01月 (ISBN: 9784861045660) 535 135-139
• リグニン利用の最新動向

  坂, 志朗 (範囲:第5章 リグニンの利用の現状と展望 1 リグニンを原料としたポリエステル)
  シーエムシー出版 2013年07月 (ISBN: 9784781308050) v, 244p p.145-152
• Functional materials from renewable sources

  Yasumitsu Uraki, Keiichi Koda, Tatsuhiko Yamada, Chihiro Oikawa, Tomohiro Aso (担当:分担執筆範囲:Novel functions of nonionic, amphiphilic lignin derivatives)
  American Chemical Society, Washington, DC, USA 2012年 (ISBN: 9780841227880) 361 243-254
• Sustainable Production of Fuels, Chemicals, and Fibers from Forest Biomass

  Keiichi Koda, Satoshi Kubo, Yasumitsu Uraki (担当:分担執筆範囲:Chemicals from lignin based on thermal fusibility and amphiphilicity)
  American Chemical Society, Washington, DC, USA 2011年 (ISBN: 9780841226432) 526 261-277
• 森林の科学―森林生態系科学入門

  中村 太士, 小池 孝良 (担当:分担執筆範囲:【コラム】リグニンを調べる)
  朝倉書店 2005年09月 (ISBN: 425447038X) 218 162

講演・口頭発表等

• Development of Lignin-based Bioploymers for Sustainable Use of Woody Biomass  [招待講演]

  Keiichi Koda

  The First International Conference of Lignocellulose in conjunction with The 10th International Symposium for Sustainable Humanosphere 2021 (ICON-LIG & ISSH 2021) 2021年09月 口頭発表（招待・特別）
• Woody Biomass Refinery -Its Significance and Future Perspective-  [招待講演]

  Keiichi Koda

  Asia Pacific Regional Meeting 2021 (APRM 2021) 2021年06月 公開講演，セミナー，チュートリアル，講習，講義等
• Lignin-based flexible film as a separator for electric double-layer capacitor Preparation of lignin-based activated carbon fiber and its electrical application  [招待講演]

  Keiichi Koda, Atsushi Kobota, Tomofumi Isozaki, Tatsuhiko Yamada, Yasumitsu Uraki

  5th ISETPP & 3rd IPEC 2016年11月 口頭発表（基調） 広州、中国 華南理工大学
  
• 森は自然の化学工場  [招待講演]

  幸田圭一

  第25回時計台サロン 農学部に聞いてみよう 2015年04月 公開講演，セミナー，チュートリアル，講習，講義等 札幌時計台2F演武場（札幌市） 北海道大学農学部／農学院／農学研究院
  
• 木質バイオマスの総合利用とその今日的意義  [招待講演]

  幸田圭一

  北海道大学総合博物館 土曜市民セミナー 2013年10月 公開講演，セミナー，チュートリアル，講習，講義等 北大総合博物館１F「知の交流」コーナー（札幌市） 北海道大学総合博物館
  
• Challenging Adventure on Lignin Chemistry  [招待講演]

  幸田圭一

  Invited Lecture at Mulawarman University 2006年09月 公開講演，セミナー，チュートリアル，講習，講義等 Samarinda, Indonesia Mulawarman University
  
• リンのNMRによるリグニン官能基の視覚化  [招待講演]

  幸田圭一

  セルロース学会北海道・東北支部主催講演会『木質バイオマスの化学的利用－育種から先端利用まで－』 2005年11月 公開講演，セミナー，チュートリアル，講習，講義等 北大農学部（札幌市） セルロース学会北海道・東北支部
  
• Oxidation of lignin in supercritical carbon dioxide  [通常講演]

  D.Argyropoulos, A. Gaspar, K. Koda

  Abstracts of Papers of the Amirian Chemical Society Vol. 229. 1155 16TH ST, NW, WASHINGTON, DC 20036 USA: AMER CHEMICAL SOC, 2005. 2005年 口頭発表（一般） San Diego ACS
  
• 製紙用パルプの塩素系漂白で生成する高分子有機塩素化合物の微生物分解挙動  [招待講演]

  幸田圭一

  北海道科学技術ネットワークセッション-若手研究者研究成果発表会・交流会- 2003年03月 その他 かでる2・7（札幌市） 〔財〕北海道科学技術総合振興センター
  
• クラフトパルプの塩素漂白過程で副生する環境有害物質の追跡  [招待講演]

  幸田圭一

  平成12年度繊維学会北海道紙パルプ技術懇談会講演会 2001年03月 公開講演，セミナー，チュートリアル，講習，講義等 北海道大学百年記念会館（札幌市） 繊維学会北海道紙パルプ技術懇談会
  

担当経験のある科目（授業）

パルプ・製紙学〔森林科学科3年次対象選択科目〕北海道大学農学部
林産学特論演習I〔修士課程対象科目〕北海道大学大学院農学院
林産学特論I〔修士課程対象科目〕北海道大学大学院農学院
森林資源科学特論演習〔修士課程対象科目〕北海道大学大学院農学院
森林資源科学特論〔修士課程対象科目〕北海道大学大学院農学院
木質バイオマス変換（化）学〔森林科学科3年次対象必修科目〕北海道大学農学部
林産製造学実験〔森林科学科3年次対象選択科目〕北海道大学農学部
林産学実習〔森林科学科2年次対象選択科目〕北海道大学農学部
英語演習〔全学1年次対象選択科目〕北海道大学全学教育
環境化学〔農学部2年次対象選択科目〕北海道大学農学部
化学概論〔農学部4年次対象教職科目（選択）〕北海道大学農学部
木質資源学演習北海道大学大学院農学院
木質資源学北海道大学大学院農学院
森林保全の科学〔全学1年次対象選択科目〕北海道大学全学教育
自然（森林）と生物、人間のかかわり〔1年次対象専門紹介科目〕全学北海道大学全学教育
森林化学実験北海道大学農学部
化学II〔全学1年次対象選択必修科目：有機化学〕北海道大学全学教育
製炭ときのこ実習北海道大学農学部
基礎化学II〔全学1年次対象選択必修科目：有機化学〕北海道大学全学教育
森林資源科学研究II〔博士課程対象研究指導〕北海道大学大学院農学院
森林資源科学研究I〔修士課程対象研究指導〕北海道大学大学院農学院
森林資源科学演習II〔博士課程対象ゼミ〕北海道大学大学院農学院
森林資源科学演習I〔修士課程対象ゼミ〕北海道大学大学院農学院
農学研究II〔博士課程対象研究指導〕北海道大学大学院農学院
農学演習II〔博士課程対象ゼミ〕北海道大学大学院農学院
農学研究I〔修士課程対象研究指導〕北海道大学大学院農学院
農学演習I〔修士課程対象ゼミ〕北海道大学大学院農学院

所属学協会

• リグニン学会   日本木材学会   繊維学会   日本腐植物質学会   ヨウ素学会   木質炭化学会   高分子学会   紙パルプ技術協会   セルロース学会   Fiber Science and Technology   Japan Humic Substances Society   The Society of Iodine Science   The Wood Carbonization Research Society   The Society of Polymer Science, Japan   Japan TAPPI   The Cellulose Society of Japan   The Japan Wood Research Society   

共同研究・競争的資金等の研究課題

• 細胞壁ミメティックス中で形成するリグニンの構造解析とその関連因子の解明

  日本学術振興会：科学研究費助成事業

  研究期間 : 2018年04月 -2021年03月 

  代表者 : 浦木 康光, 重冨 顕吾, 堤 祐司, 玉井 裕, 吉永 新, 高部 圭司, 綿岡 勲, 幸田 圭一

   

  本研究では、セルロースにヘミセルロースを吸着させた人工多糖類マトリックスを作製し、このマトリックス中でのリグニンの形成を検討した。その結果、キシランはリグニンの形成と、リグニンの主要単位間結合である8-O-4’結合を寄与するが、グルコマンナンはリグニンの形成を阻害することが分かった。さらに、一次細胞壁に特有のキシログルカンは5-5’結合を誘導することが分かり、ヘミセルロースがリグニンの形成に大きな影響を与えることが明らかとなった。 また、単離リグニンの溶液構造解析より、5-5’結合の増加は大きな分子量を持つリグニン画分をよりコンパクトな構造にし、低い粘性発現に関与すことも明らかとなった。
• ニトロベンゼン酸化法の改良によるリグニンの単位間構造解析の拡張

  日本学術振興会：科学研究費補助金 基盤研究（C）

  研究期間 : 2018年04月 -2021年03月 

  代表者 : 幸田 圭一
• リグニンは落葉の生分解を強く規定するか？

  日本学術振興会：科学研究費補助金 基盤研究（C）

  研究期間 : 2015年04月 -2018年03月 

  代表者 : 幸田圭一
• 木材細胞壁模倣多糖類マトリックス中でのリグニンの形成とその構造決定因子の解明

  日本学術振興会：科学研究費補助金 基盤研究（A）

  研究期間 : 2014年04月 -2018年03月 

  代表者 : 浦木康光
• 積雪下でのリグニン分解活性を備えたリター分解菌類の分子系統および生態生理

  日本学術振興会：科学研究費助成事業

  研究期間 : 2013年04月 -2016年03月 

  代表者 : 宮本 敏澄, 幸田 圭一, 重冨 顕吾

   

  積雪下で分解されつつあるリターよりリグニン分解能をもつ菌類を分離し、帰属する分類群やその生態、リグニン分解酵素の同定と温度特性を調べた。さらに積雪下のリター分解過程でのリグニン分解の正確な定量技術の検証を行なった。その結果、積雪下でリグニン分解に関わると考えられる菌類は多様な分類群に属する菌類により構成され、多様な植物種の落葉に生息していた。リグニン分解酵素については検討した５菌株のいずれにおいても、4℃で活性のあるLac、LiP、MnPが認められた。また、新たなリグニン定量法により積雪下のリグニン分解は従来考えられていたよりも速い速度で進行することが明らかになった。
• 公募研究課題３「木質リグニンからの材料製造技術の開発」

  農林水産省 農林水産技術会議：委託プロジェクト研究「農山漁村におけるバイオ燃料等生産基地創造のための技術開発」（平成24年度～27年度）

  研究期間 : 2012年04月 -2016年03月 

  代表者 : 大原誠資
• 広葉樹の道管相互壁孔に常在する抽出成分の同定と通水への影響解析

  日本学術振興会：科学研究費補助金 基盤研究（C）

  研究期間 : 2011年04月 -2015年03月 

  代表者 : 佐野雄三
• 冷温帯林における積雪下でのリター分解菌類群集の組成とその分解酵素活性

  日本学術振興会：科学研究費補助金 基盤研究（C）

  研究期間 : 2009年04月 -2012年03月 

  代表者 : 宮本敏澄
• 人工細胞壁を用いたヘミセルロースの機能解明と機能性材料の創出

  日本学術振興会：科学研究費助成事業

  研究期間 : 2009年 -2011年 

  代表者 : 浦木 康光, 玉井 裕, 幸田 圭一, 平井 卓郎, 杉山 淳司

   

  本研究では、細胞壁の構造を模倣した人工細胞壁用いて、細胞壁中のヘミセルロースの機能を解明することと、ヘミセルロース吸着人工細胞壁を肝実質細胞の培養基質として利用するための検討を行った。人工細胞壁の基本骨格はハニカムパターン化セルロースフィルムであり、これに、広葉樹の代表的ヘミセルロースであるキシランとカラマツに特有なアラビノガラクタン(AG)を吸着させ、その物性変化を追跡した。両ヘミセルロースとも吸着によりフィルムの引張強度を向上させた。キシラン吸着フィルムをマイクロ波処理することで、吸着を強固にでき、弾性率が向上することを見出した。また、力学測定の結果を基に、木材の荷重下における変形モデルの検証を行ったところ、Bending-strerching modelがハニカム状の配列を取る細胞壁断面の変形を適確に表現していることが明らかとなった。 一方、培養基質としての検討では、小孔径のハニカムフィルムが肝細胞の機能を発現させると報告されているスフェロイドを形成させ、AGの吸着で見かけ上の接着細胞数は増加した。しかし、生細胞数は減少した。この結果より、弱い吸着しか示さないAGは培養中に溶出して細胞接着を阻害することが示された。また、大孔径フィルムでは、一つの孔に一つの細胞が嵌り込む現象が観測され、細胞アレイとしての有用性が示唆されたが、接着細胞数が少なく、この改善が今後実用に向けての課題あることも分った。
• Identification of extractives occurring in vessel perforation in hardwood

  Cooperative Research

  研究期間 : 2011年
• 木質バイオマスの利活用を指向したリグニン単位間結合の新規切断方法の開発

  経常研究

  研究期間 : 2005年 -2010年 

  代表者 : 幸田圭一
• Biodegradation and Environmental Fate of Lignin and Lignin-like Substances in Forest Ecosystem

  Ordinary Research

  研究期間 : 2006年
• A Novel Procedure for Ether Cleavage of Lignin Interunit Linkages under Mild Reaction Conditions -For Complete Utilization of Woody Biomass-

  Ordinary Research

  研究期間 : 2005年
• 製紙用パルプ漂白排水成分の生分解性ならびに環境毒性の総合的評価系の確立

  文部科学省：科学研究費補助金 若手研究（B）

  研究期間 : 2003年04月 

  代表者 : 幸田圭一

   

  (※North Carolina State Universityでの博士研究員（2003年7月～2005年5月）に内定したため、交付決定後、辞退)
• パルプの塩素漂白で生成する高分子塩素化合物の代謝モデル系の確立

  ノーステック財団（北海道科学技術振興財団）：平成13年度一般研究奨励事業 若手研究者研究奨励補助金

  研究期間 : 2001年04月 -2002年03月 

  代表者 : 幸田圭一

産業財産権

• 特開2019-108441(P2019-108441A).:組成物  2019年07月04日

  浦木康光, 幸田圭一, 今野晴男  国立大学法人北海道大学;日本製紙株式会社