研究者データベース

研究者情報

マスター

アカウント(マスター)

  • 氏名

    浦木 康光(ウラキ ヤスミツ), ウラキ ヤスミツ

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, バイオテクノロジー学特論, Advanced Biotechnology, 修士課程, 農学院, バイオテクノロジー、糖質酵素、mRNA分解、植物ウイルスベクター、糖質生合成、酵素改変、木質資源、食品機能、微生物資源、微生物バイオプロセス、技術・データ駆動型
  • 2021, バイオテクノロジー学特論演習, Advanced Seminar on Biotechnology, 修士課程, 農学院, バイオテクノロジー,生物利用・物質生産
  • 2021, 大学院共通授業科目(一般科目):自然科学・応用科学, Inter-Graduate School Classes(General Subject):Natural and Applied Sciences, 修士課程, 大学院共通科目, バイオテクノロジー、糖質酵素、mRNA分解、植物ウイルスベクター、糖質生合成、酵素改変、木質資源、食品機能、微生物資源、微生物バイオプロセス、技術・データ駆動型
  • 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, 環境と人間, Environment and People, 学士課程, 全学教育, 食のバリューチェーン、Society 5.0、エネルギー、異分野融合、持続可能性、フィールド、ロバストネス(強靱性)
  • 2021, 化学Ⅱ, Chemistry II, 学士課程, 全学教育, 有機化合物、官能基、分子構造、化学的性質、化学反応、機能性有機物、生体関連有機物質
  • 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, 卒業論文, Graduation Thesis, 学士課程, 農学部, 森林科学に関する研究、主体性、まとめる能力、伝える能力、質問への応答能力、
  • 2021, 森林科学演習Ⅰ, Seminar on Forest ScienceⅠ, 学士課程, 農学部, 森林科学、論理構築、発表技法、論文読解法、ゼミナール
  • 2021, 森林科学演習Ⅱ, Seminar on Forest ScienceⅡ, 学士課程, 農学部, 森林科学、論理構築、発表技法、論文読解法、ゼミナール

researchmap

プロフィール情報

学位

  • 理学博士(北海道大学)
  • 理学修士(北海道大学)

プロフィール情報

  • 浦木, ウラキ
  • 康光, ヤスミツ
  • ID各種

    200901010222264093

対象リソース

業績リスト

研究キーワード

  • 木質資源化学   多糖類化学   高分子化学   Polysaccharide Chemistry   Polymer Chemistry   Wood Chemistry   

研究分野

  • ライフサイエンス / 木質科学
  • ナノテク・材料 / 生体化学
  • ナノテク・材料 / 高分子化学

経歴

  • 2008年 - 現在 北海道大学 大学院農学研究院 教授
  • 2006年 - 2008年 - 北海道大学大学院農学研究院 准教授
  • 1999年 - 2006年 Associate Professor,Graduate School of Agriculture, Hokkaido University
  • 2006年 - Associate Professor,Research Faculty of Agriculture, Hokkaido University
  • 1994年 - 1999年 北海道大学農学部 助教授
  • 1994年 - 1999年 Associate Professor,Faculty of Agriculture, Hokkaido University
  • 1989年 - 1994年 北海道大学農学部林産学科木材化学講座 助手
  • 1989年 - 1994年 Research Associate,Faculty of Agriculture, Hokkaido University
  • 1987年 - 1989年 北海道大学理学部高分子学科 教務職員
  • 1987年 - 1989年 Research Associate,Faculty of Science, Hokkaido University

学歴

  •         - 1987年   北海道大学   理学研究科   高分子学専攻博士課程中退
  •         - 1987年   北海道大学
  •         - 1986年   北海道大学   理学研究科   高分子学専攻
  •         - 1986年   北海道大学
  •         - 1984年   北海道大学   理学部
  •         - 1984年   北海道大学

委員歴

  • 2019年10月 - 現在   リグニン学会   理事
  • 2018年04月 - 現在   高分子学会北海道支部   監事
  • 2016年07月 - 現在   日本木材学会   理事   日本木材学会
  • 2010年04月 - 現在   セルロース学会   理事
  • 2009年   高分子学会   理事および北海道支部長   高分子学会

受賞

  • 2020年09月 セルロース学会 セルロース学会賞
     
    受賞者: 浦木康光
  • 2009年 第7回北の木材科学賞
  • 2008年 第6回北の木材科学賞
  • 2007年 第5回北の木材科学賞
  • 2006年 第4回北の木材科学賞
  • 2006年 日本木材学会賞
  • 2006年 The Japan Wood Research Society Prize for 2006
  • 2005年 第3回北の木材科学賞
  • 2003年 第1回北の木材科学賞

論文

  • Keiichiro Takeuchi, Shiori Suzuki, Kengo Shigetomi, Yasumitsu Uraki
    Journal of Wood Chemistry and Technology 1 - 11 2024年09月12日
  • Shogo Taira, Ikuto Tanouchi, Shiori Suzuki, Tadahisa Iwata, Yasumitsu Uraki
    Cellulose 31 3 1559 - 1568 2024年02月 [査読有り]
  • Fumiya Honda, Shogo Taira, Shiori Suzuki, Kazuhiro Shikinaka, Kengo Shigetomi, Yasumitsu Uraki
    Holzforschung 2023年08月31日 [査読有り][通常論文]
     
    Abstract A lignin-based gel prepared by the chemical crosslinking of hardwood acetic acid lignin (AL) with poly(ethylene glycol) diglycidyl ether has been reported to shrink in water and organic solvents but swell specifically in aqueous binary solutions. In this study, the AL-based gel was also found to swell in lithium-salt-containing organic solvents, namely, liquid electrolytes. The uptake of salt solutions reached five times the dry weight of the gel. The ionic conductivity of the gel swollen with 1 M LiBF4 in propylene carbonate or a mixed solution (1:1, v/v) of ethylene carbonate and dimethyl carbonate exceeded 1 mS cm−1 at room temperature (25 °C), suggesting that this gel can be applied as a gel electrolyte for lithium-ion batteries (LIBs). A prototype LIB was assembled with the AL-based gel electrolyte and LiCoO2/graphite-based electrodes and exhibited low bulk and charge transfer resistances of 4.1 and 9.7 Ω, respectively. Moreover, its initial specific capacity reached 104 mAh g−1 at a current density of 28 mA g−1, which is comparable to that of a reference LIB assembled using a commercial polyethylene separator. These results indicate the significant potential of this lignin-based gel for application in energy storage devices.
  • Nutthira Pakkang, Shiori Suzuki, Kengo Shigetomi, Yasumitsu Uraki
    HOLZFORSCHUNG 2022年12月 
    This study aimed to assemble a high-performance electric double-layer capacitor (EDLC) using a hardwood kraft lignin (HKL)-based separator and HKL-based electrodes, which were fabricated from a nonwoven mat of electrospun HKL fibers. The separator was prepared by the thermostabilization of the mat derived from a mixed dope of HKL, hexamethylenetetramine, and polyethylene glycol (1.66/0.50/0.09, w/w) for electrospinning. Although a mat-type HKL-based electrode containing conductive carbon black (CB) has been reported to be suitable for a commercial cellulosic separator, this electrode was found to be unsuitable for the HKL-based separator because of its rough surface and poor contact with the separator interface. Hence, a powder-type electrode with a smooth surface was fabricated by grinding the mat, followed by casting with a carboxymethyl cellulose aqueous solution, and its EDLC possessed high energy (49 Wh kg(-1)) and power densities (151 kW kg(-1)). Moreover, to provide a simple process for electrode fabrication, another mat-type electrode was fabricated by adding CB to the mixed dope, followed by electrospinning, carbonization, and steam activation. The resultant EDLC exhibited excellent electrochemical performance with energy (58 Wh kg(-1)) and power densities (55 kW kg(-1)).
  • Kengo Shigetomi, Mana Tokizawa, Yasumitsu Uraki
    Journal of Wood Science 68 1 2022年12月 
    Abstract To establish a facile methodology for the elucidation of the lignin chain-growth mechanism, the preparation of monolignol that does not show NMR signals in the dehydrogenative polymer (DHP) was attempted. As a monolignol of which aliphatic moieties were deuterated, coniferyl alcohol-d7 was successfully synthesized from protocatechualdehyde and malonic acid via the modified Knoevenagel–Doebner reaction and the Luche reduction. The process achieved high to excellent deuteration efficiencies at the aimed positions (i.e., methoxy: > 99%D, α: > 99%D, β: 92%D, and γ: 98%D). DHP was prepared solely from coniferyl alcohol-d7, and its NMR spectra were compared with those from coniferyl alcohol. The results indicated that: (1) the deuterium atoms at methoxy group, α- and β-positions were highly retained even in the DHP, and their signals were effectively suppressed; (2) a part of the deuterium at γ-position was replaced with H through the reaction; (3) meanwhile, the formation of γ-CH2 was negligible. This study demonstrated that coniferyl alcohol-d7 could “silence” the majority of the signals even when converted to DHP. Highly deuterated monolignols can be a unique molecular tool that can differentiate the signals of interest from those derived from monolignols.
  • Yan Lyu, Shiori Suzuki, Hiroki Nagano, Kengo Shigetomi, Yutaka Tamai, Yuji Tsutsumi, Yasumitsu Uraki
    Carbohydrate Polymers 301 120305 - 120305 2022年11月07日 [査読有り]
  • Manish Kumar, Shogo Taira, Nutthira Pakkang, Kengo Shigetomi, Yasumitsu Uraki
    Advances in Natural Sciences: Nanoscience and Nanotechnology 13 2 2022年06月 
    In this study, lignin-based conducting carbon nanofiber mat was prepared by electrospinning followed by a thermal treatment. Lignin is a sustainable carbon precursor. Polyacrylonitrile (PAN) acts as a binder polymer, which increases the viscosity of the lignin solution using dimethylformamide solvent and helps in the formation of a stable nanofiber. The mixture solution was electrospun, followed by stabilisation and carbonisation to yield carbon nanofibers (CNFs). A fixed amount of external load was provided to the lignin fiber mat during the stabilisation procedure and then carbonised to yield stretched carbon nanofibers (S-CNFs). On stretching the mat, surface conductivity was enhanced by 3 times, and the surface area by 1.3 times compared to that of non-stretched CNFs. Finally, the electric double layer capacitor (EDLC) was assembled with the resulting (CNFs and S-CNFs) nanofiber mat using 6 M of KOH aqueous solution. S-CNFs mat exhibits a specific capacitance of 266 F g−1, which was higher than that of CNFs, i.e. 258 F g−1 at a scan rate of 5 mVs−1
  • Yoshimichi Sakakibara, Yusuke Sai, Yasumitsu Uraki, Makoto Ubukata, Kengo Shigetomi
    HETEROCYCLES 104 1 140 - 158 2022年 
    The Mitsunobu inversion is one of the reliable methods for stereospecific substitution of chiral alcohols, but its deacylation step has limited the substrate scope. Here, we propose a new template of the Mitsunobu acylate that can be deacylated in non-alkaline treatments. The 3,4-dihydroxy-2-methylenebutanoate was selected as a template structure, and its acetonide- or bisTBS derivatives were synthesized. The latter especially showed excellent inversion efficiency (up to >99% ee) and good elimination performance for a series of secondary alcohols in near-neutral conditions. The results demonstrated the applicability of the new template for the substrates labile in alkaline conditions, such as alpha-hydroxyesters.
  • Yan Lyu, Tatsuya Matsumoto, Shogo Taira, Kazumasa Ijiri, Arata Yoshinaga, Kengo Shigetomi, Yasumitsu Uraki
    Cellulose 28 15 9907 - 9917 2021年10月 [査読有り]
     
    To elucidate the effects of polysaccharides, cellulose, water-soluble xylan (WXY), galactoglucomannan (GGM) and xyloglucan (XG) on lignification in vitro, artificial polysaccharide matrices were prepared from a combination of cellulose and hemicelluloses, and dehydrogenation polymer (DHP) was synthesized from coniferyl alcohol in the presence of the matrices by using horseradish peroxidase (HRP). Prior to DHP formation, interactions between cellulose and hemicelluloses were investigated with equilibrium adsorptions of the hemicelluloses on bacterial cellulose (BC) films and with quartz crystal microbalance with dissipation technique (QCM-D) to determine their adsorption on cellulose nanofibers (CNFs). Both analyses showed that the order of adsorption amounts was XG > GGM > WXY. The QCM-D experiments also suggested that HRP strongly interacted with cellulose rather than hemicelluloses. The amount of DHP generated in the XG-BC matrix was the largest among the prepared matrices, and XG facilitated the formation of 5–5′ interunitary linkages. Thus, XG must be involved in the lignification in primary wood cell wall. On the other hand, the amount of DHP in the GGM-BC matrix was the smallest, indicating that GGM hampered lignification. Graphic abstract: [Figure not available: see fulltext.]
  • Shogo Taira, Yuriko Usukura, Mitsukuni Nishida, Kengo Shigetomi, Yasumitsu Uraki
    Holzforschung 75 8 765 - 772 2021年08月26日 
    Abstract A lignin-based gel (AL-PE gel) was obtained from hardwood acetic acid lignin (AL) and poly(ethylene glycol) diglycidyl ether (PE) as a cross-linker at a high AL concentration, while the reaction at a lower AL concentration yielded an amphipathic derivative (am-AL-PE). The gel has been reported to swell in aqueous ethanol but shrink in pure water and ethanol. In the present work, swelling behaviors in other aqueous binary solvents and the swelling mechanism were investigated to explore novel lignin-based functional materials, such as stimuli-and/or environment-responsive gels. The AL-PE gel swelled in aqueous methanol, isopropanol, acetone, and tetrahydrofuran, and the order of swelling in the solvents was consistent with that of the am-AL-PE. Spin-spin relaxation time (T 2 ) measurements with 1H NMR analysis of the gel in aqueous acetone revealed that gel swelling was closely related to an increasing T 2 of acetone bound to the gel network. The nature of the lignin moiety in the gel also enabled a pH response, and the amphipathic nature of the gel provided it with a function as an absorbent for cationic surfactants. The results of this study can contribute to the valorization of lignin as a main component for solvent sensors and environmental purification materials.
  • Yoshimichi Sakakibara, Kota Osada, Yasumitsu Uraki, Makoto Ubukata, Kengo Shigetomi
    Bioscience, Biotechnology, and Biochemistry 85 2 215 - 222 2021年02月18日 
    ABSTRACT Hinokitiol has a broad antibacterial activity against bacteria and fungi. While its biosynthetic pathway has been intensively studied, its dynamics in natural environments, such as biodegradation pathway, remain unclear. In this study, the authors report a direct deuterium labeling of hinokitiol as a traceable molecular probe to serve those studies. Hinokitiol was subjected to the H2-Pd/C-D2O conditions and deuterated hinokitiol was obtained with excellent deuteration efficiencies and in moderate yield. The 1H and 2H NMR spectra indicated that all ring- and aliphatic hydrogens except that on C-6 were substituted by deuterium. According to the substrate scope and computational chemistry, deuteration on tropolone ring was suggested to proceed via D+-mediated process, and which was supported by the results of the experiment with trifluoroacetic acid and Pd(TPP)4. On the other hand, the deuteration on aliphatic group was predicted to be catalyzed by Pd(II) species.
  • Shiho Takahashi, Yasumitsu Uraki, Tatsuhiko Yamada
    BioResources 16 1 1787 - 1797 2021年01月22日 [査読有り]
     
    A lignin-based water reducer for concrete was prepared from softwood soda lignin. The soda lignin and the lignin-polyethylene glycol (PEG) derivative were modified with ozone to improve their performance as water reducers. The performance of ozone-treated soda lignin was superior than untreated soda lignin and commercial lignosulfonate-type water reducers in the mortar flow test. The soda lignin treated with a high ozone charge showed better performance than lignin treated with a low ozone charge. The ozone treatment improved the performance of the lignin-PEG derivative water reducer as well. The lignin-PEG derivative water reducer with a longer PEG chain length showed better performance than that of the shorter PEG chain. The zeta potential of cement suspension with the ozone-treated soda lignin showed a higher negative value than the untreated soda lignin. The data of zeta potential analysis suggested that the electrostatic repulsion force of cement particles with the ozone-treated lignin would be larger than the untreated lignin.
  • Nutthira Pakkang, Manish Kumar, Shogo Taira, Keiichi Koda, Kengo Shigetomi, Yasumitsu Uraki
    Holzforschung 74 6 577 - 588 2020年06月25日 [査読有り]
     
    Abstract 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.
  • 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]
     
    Abstract 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.
  • 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]
  • 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04月 [査読有り]
  • Yuu Hasegawa, Mitsunori Mori, Keiichi Koda, Yasumitsu Uraki
    Journal of Wood Chemistry and Technology 40 1 1 - 14 2020年01月02日 
    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.
  • 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07月04日
  • 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
  • Linping Wang, Yasumitsu Uraki, Keiichi Koda, Aori Gele, Xuesong Zhou, Fangeng Chen
    Holzforschung 73 4 363 - 369 2019年04月24日 [査読有り]
     
    Abstract 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 LL658 nm and LL785 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 M0.24 in THF and [η]/ml g−1=0.142 M0.26 in dimethyl sulfoxide (DMSO). These results demonstrate that Ac-HWKL has a more compact structure in an organic solvent than polystyrene.
  • Shogo Taira, Makoto Kurihara, Keiichi Koda, Kazuki Sugimura, Yoshiyuki Nishio, Yasumitsu Uraki
    Cellulose 26 1 569 - 580 2019年01月
  • Nutthira Pakkang, Yasumitsu Uraki, Keiichi Koda, Manit Nithitanakul, Ampira Charoensaeng
    Journal of Surfactants and Detergents 21 6 809 - 816 2018年11月 [査読有り]
  • 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/).
  • 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.
  • Ligninolytic Activity at 0 °C of Fungi on Oak Leaves Under Snow Cover in a Mixed Forest in Japan
    浦木 康光
    Microbial Ecology 74 2 322 - 331 2017年02月 [査読有り][通常論文]
  • 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.
  • 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.
  • 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.
  • 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.
  • 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.
  • Yamamoto Yoko, Cheng Ningning, Igarashi Kiyohiko, Koda Keiichi, Uraki Yasumitsu
    ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY 249 2015年03月22日 [査読有り][通常論文]
  • Kukjin Yoon, Shiho Takahashi, Thi Thi Nge, Olov Karlsson, Akiko Nakagawaizumi, Hiroshi Ohi, Yasumitsu Uraki, Tatsuhiko Yamada
    BIORESOURCES 10 1 912 - 921 2015年 [査読有り][通常論文]
     
    Softwood lignin prepared by soda-anthraquinone (AQ) cooking does not have thermal melting characteristics. To improve the properties of softwood soda-AQ lignin, we have invented a new method of lignin modification using dried black liquor powder by a spray dryer system and polyethylene glycol (PEG). In this process, black liquor powder was directly treated with PEG under alkaline conditions to produce PEG-modified lignin (alkaline PEG treatment). Dried black liquor powder prepared by a spray dryer was dissolved into PEG and heated at either 120 or 160 degrees C at atmospheric pressure. The modified lignin (alkaline PEG-treated lignin) was precipitated with acid and recovered by filtration. The alkaline PEG-treated lignin showed adequate thermal melting characteristics. The treatment temperature and the molecular weights of PEG considerably affected the thermal properties of the alkaline PEG-treated lignin. There was an addition reaction of the PEG to the lignin hydroxyl group at the alpha-(alpha-) carbon. However, in the acid precipitation step, if the mixture was allowed to set unfiltered for a long time, the PEG bonded with the lignin was hydrolyzed, which yielded the original soda-AQ lignin and PEG polymer.
  • Shiho Takahashi, Shuji Hosoya, Masami Hattori, Masakazu Morimoto, Yasumitsu Uraki, Tatsuhiko Yamada
    JOURNAL OF WOOD CHEMISTRY AND TECHNOLOGY 35 5 348 - 354 2015年 [査読有り][通常論文]
     
    We have developed a high-performance lignin-based water-reducing admixture. In this study, softwood soda-anthraquinone lignin was modified with mono-epoxide polyethylene glycols having chain lengths of 10, 25, and 50 mol (the number of repeating units of ethylene oxide). The mortar flow and concrete slump flow tests were used to investigate the performance of the lignin derivatives as a water-reducing admixture. All tested lignin-PEG derivatives performed considerably better than a commercial lignosulfonate water-reducing admixture in the mortar flow test. In particular, the derivative with a PEG chain length of 50 mol performed excellently in both tests. The optimum PEG content for mortar dispersion was approximately 40% for lignin derivatives with a PEG chain length of 50 mol; this content exhibited a dispersing effect that was four times higher than that of the lignosulfonate water-reducing admixture. The strength of concrete containing the lignin derivatives was almost the same strength as that of concrete containing the commercial lignosulfonate water-reducing admixture.
  • 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.
  • 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.
  • 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.
  • ShihoTakahashi, Masami Hattori, Masakazu Morimoto, Yasumitsu Uraki, Tatsuhiko Yamada
    Journal of Wood Chemistry and Technology 34 31 - 38 2014年01月 [査読有り][通常論文]
  • Tomohiro Aso, Keiichi Koda, Satoshi Kubo, Tatsuhiko Yamada, Isamu Nakajima, Yasumitsu Uraki
    Journal of Wood Chemistry and Technology 33 4 286 - 298 2013年 [査読有り][通常論文]
  • 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.
  • 浦木 康光
    紙パ技協誌 66 10 1120 - 1125 紙パルプ技術協会 2012年10月01日 
    バイオリファイナリーとは,「バイオマスを余すことなく,物質とエネルギーとして使うしくみのこと」と定義され,製紙産業は,木質バイオマスのリファイナリーを化学的に実践している産業である。しかし,セルロースのみを使用する製紙産業やバイオエタノール製造では,その副産物であるリグニンの利活用も脱化石資源構築には,重要な課題である。そこで,本稿では,リグニンに付加価値を与える変換方法について概説する。
    21世紀に入り,リグニンから炭素繊維(CF)を製造する技術が多数報告されるようになった。その第一段階の紡糸技術も溶融紡糸の他に,エレクトロスピニング等の手法が確立されて,繊維の多様化が図られた。しかし,これらの繊維からCFを調製するには,長い処理時間を要求される不融不溶化が必要であり,時間短縮が,課題となっていた。筆者らと森林総合研究所との共同研究により,スギ材のポリエチレンオキシドを用いたソルボリシス反応で得られたリグニン(PEO―Lig)は,容易に溶融紡糸ができ,2時間の農塩酸処理で不融不溶化が達成された。この繊維を炭素化することで,従来のリグニンCFと遜色ない強度をもつCFが得られた。
    また,化学修飾によるリグニンの機能化について検討した。エポキシ化されたポリエチレングリコールと種々のリグニンを反応させて,界面活性能を有する両親媒性リグニン誘導体を調製した。この誘導体は,セルラーゼと相互作用し,セルラーゼの酵素糖化を向上させたばかりでなく,糖化後の酵素活性も高いレベルで保持する能力を有していることが明らかとなった。さらに,この誘導体をセメントと混合することにより,セメントの分散性を顕著に向上させて,リグノスルホン酸より優れたセメント減水剤として機能することも示された。
  • 浦木 康光
    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.
  • 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.
  • 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.
  • Masato Ogawa, Teuku B. Bardant, Yasutaka Sasaki, Yutaka Tamai, Seiichi Tokura, Yasumits Uraki
    BIORESOURCES 7 1 236 - 245 2012年 [査読有り][通常論文]
     
    Activated carbons (ACs) were prepared from biomass of Borneo island (wood charcoal, peat, and coconut husk) by using an electricity-free furnace, of which the energy source was exclusively wood charcoal. This furnace was comprised of two parts, an inner vessel equipped with water inlet for steam activation and an outer shell as a heating part for the inner vessel. The inside temperature of the inner vessel was able to reach over 1000 degrees C. Peat and wood charcoal were converted to AC by carbonization followed by steam activation, and the specific BET surface areas of resultant ACs were 889 m(2)/g and 749 m(2)/g, respectively. A mobile apparatus for water purification was newly designed and fabricated with the resultant AC, together with a white quartz sand, which is called keranggas in Kalimantan. The CODOH of both polluted creek water by the University of Palangka Raya and Kahayan River water were remarkably decreased by the purification with the designed apparatus from 20.0 mgO/L to 0.93 mgO/L, and 18.2 mgO/L to 0.74 mgO/L, respectively. Thus, the newly designed furnace and purification apparatus were shown to be highly effective tools to produce a promising agent for water purification and to produce clarified water without use of electricity, respectively.
  • 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.
  • 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.
  • 久保 智史, 山田 竜彦, 本間 春海, 浦木 康光
    バイオマス科学会議発表論文集 4 66 - 67 一般社団法人日本エネルギー学会 2009年 
    Japanese cedar was subjected to the acid catalyzed solvolysis using a mixed solvent of glycols and cyclic carbonates. In this one step solvolysis, lignin having oxyalkyl chains such as polyethylene glycol (EG) chains was prepared together with furfurals and levulinic acid from carbohydrate components. Solvolysis lignin was expected to be utilized as macromolecular surfactants from its amphiphile like chemical structure. However, dissolution properties to water and/or chain flexibility of introduced oxyalkyl chains of solvolysis lignin must be improved for the surfactant application. Another possibility of the solvolysis lignin could be found in the plastic applications. Thermal molding abilities of solvolysis lignin could be improved by the introduction of propylene glycol units in oxyalkyl chains instead of EG units. Solvolysis lignins having polypropylene glycol chains could be spun continuously by melt spinning using a laboratory mixing extruder. This lignin fibre could be thermally stabilized by removing PPG chains through a simple acid washing process. This result would indicate that solvolysis lignin fibres could be converted into carbon fibers with simplified process.
  • Harumi Homma, Yasumitsu Uraki, Makoto Ubukata, Satoshi Kubo, Tatsuhiko Yamada
    PROCEEDINGS OF INTERNATIONAL CONFERENCE ON PULPING, PAPERMAKING AND BIOTECHNOLOGY 2008: ICPPB '08, VOL I 654 - 658 2008年 [査読有り][通常論文]
     
    Amphiphilic lignin derivatives were prepared by the polyoxyethylation of acetic acid lignin (AL) using commerclaily available polyethylene glycol diglycidylethers (PEGDE) with 1, 9, 13 and 22 of the repeating unit number (n) of ethylene oxide (EO) in order to make use of them as a nonionic polymeric surfactant. The resultant derivatives revealed significant surface activity, such as reduction of water surface tension and obvious critical micelle concentrations (CMC), although both PEGDE and PEG showed very week. The CIVIC was comparable to a commercial anionic lignin surfactant, lingosulfonate, but was much higher than that of Triton (R) X-100 that was commercial PEG-based nonionic surfactant. The surface activity of AL derivative was further improved by the reaction with monoepoxide compound, ethoxy-(2-hydroxy)-propoxy- polyethylene glycol glycidylether (EPEGGE). The surface tension of water was depressed by the addition of the EPEGGE-AL preparation to the same level as that with Triton (R) X-100, although CMC was still higher.
  • 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.
  • 浦木 康光
    繊維学会誌 63 1 P.18 - P.22 The Society of Fiber Science and Technology, Japan 2007年
  • Uraki Y, Matsumoto C, Kishimoto T, Ubukata M, Yabu H, Tanaka M, Shimomura M
    Abstracts of Papers of the American Chemical Society 233 739  2007年 [査読有り][通常論文]
  • Yasumitsu Uraki, Satoshi Kubo
    MOKUZAI GAKKAISHI 52 6 337 - 343 2006年 [査読有り][通常論文]
     
    Fibrous carbons, such as carbon fibers and activated carbon fibers, have valuable functions as industrial precursors for the production of carbon fiber-reinforced plastics, adsorbents and so on. Approaching global environmental issues are leading toward the utilization of biomass-derived carbonaceous materials to replace the current petrochemical-based industry Woody biomass is comprised of multiple components resulting from highly complex metabolic systems. It is therefore more difficult to produce functional carbonaceous materials directly from woody biomass as compared to fossil resources. These disadvantages of the direct utilization of woody biomass have promoted approaches to establish effective systems for biomass refining into its components, and even to develop new functionalities for biomass carbons with defined differentiation from fossil-based carbons. In this review, current developments of woody biomass-based fibrous carbons are introduced.
  • Uraki Yasumitsu, Matsumoto Chiaki, Tamai Yutaka, Kishimoto Takao, Ubukata Makoto, Yabu Hiroshi, Tanaka Masaru, Shimomura Masatsugu, Beihai H, Shiya F, Fangeng C
    Research Progress in Pulping and Papermaking, 2006 898 - 903 2006年 [査読有り][通常論文]
  • Synthesis of polymeric lignin model compounds composed of β-O-4 structure and their analysis by MALDI-TOF-MS
    Takao Kishimoto, Yasumitsu Uraki, Makoto Ubukata
    Appita Annual Conference 2 345 - 348 2005年 
    The β-O-4 structure is the most abundant substructure in lignin. Lignin related polymers composed of only β-O-4, structure were prepared from simple aromatic compounds as starting materials. Acetophenone derivatives were brominated, polymerized in the presence of K2CO3, and reduced with NaBH4 to give the lignin related polymers. They are linear polymers which resemble natural lignins in their structure, although they do not have γ-hydroxymethyl group. The number average degree of polymerization (DPn) was determined with peracetate of the polymers by gel permeation chromatography. DPn of guaiacyl type polymers were 15.2-21.4, where syringyl type 11.3 andp-hydroxyphenyl type 16.9. Very resenctly, we have suceeded in the chemical synthesis of β-O-4 type lignin polymer with three-carbon side chain, as well. DPn and DPw reached 15.8 and 30.6, respectively.
  • Delignification mechanism during high-boiling solvent pulping. Part 6: Changes in lignin structure analyzed by 1H-13C correlation 2-D NMR spectroscopy
    Kishimoto T, Ueki A, Takamori H, Uraki Y, Ubukata M
    Organic & Biomolecular Chemistry 3 1067 - 1073 2005年 [査読有り][通常論文]
  • Kishimoto, T, Y. Uraki, M. Ubukata
    Org. Biomol. Chem. 3 6 1067 - 1073 2005年 [査読有り][通常論文]
  • Uraki Y, Otsuka H, Ubukata M, Yabu H, Tanaka M, Shimomura M
    Polymer Preprints, Japan 54 1 1561  2005年 [査読有り][通常論文]
  • Nemoto J, Uraki Y, Kishimoto T, Sano Y, Funada R, Obata N, Yabu H, Tanaka M, Shimomura M
    Bioresource Technology 96 17 1955 - 1958 2005年 [査読有り][通常論文]
  • A Nakamura, Y Uraki, T Kishimoto, M Ubukata
    2nd International Symposium on Technologies Of Pulping, Papermaking and Biotechnology on Fiber Plants, Proceedings 521 - 524 2004年 [査読有り][通常論文]
     
    An aim of this study was to investigate interactions of a monolignol [coniferyl alcohol (CA)] and its glucoside [coniferin (CR)] with xylan as one of hemicellulose by using the surface plasmon resonance (Biacore TM) to clarify the tranportation of lignin precursor from cell in the lignification process. Xylan isolated from birch was oxidized with periodate to generate aldehyde group, and then the resulting xylan was immobilized onto carboxymethyl (CM)-dextran as a support of sensor chip by the reductive amination to give a ligand on the sensor chip. Various concentrations of CA and CR in aqueous solution as analytes were introduced into the ligand, and adsorption was monitored on the basis of the surface plasmon resonance. As a result, the adsorption capacity of the oxidized xylan to CA was much larger than that of CR. The xylan had high affinity to monolignol. It is proposed that monolignol could be supplied from cytoplasm for ligninfication but not its glucoside.
  • T Imura, Y Uraki, T Kisimoto, M Ubukata
    2nd International Symposium on Technologies Of Pulping, Papermaking and Biotechnology on Fiber Plants, Proceedings 591 - 594 2004年 [査読有り][通常論文]
     
    Hydroxypropyl-cellulose bearing lignin (HPC-L) and hydroxypropyl-cellulose (HPC) were preprared from the unbleached acetic acid pulp and pure cellulose by hydroxypropylation using propylene oxide. The HPC-L showed the lower critical solution temperature (LCST) at 38 degrees C, which was five degree lower than that of HPC. These HPC preparations were converted to urethane- and epoxy-types of chemical gels by crosslinking using hexamethylene diisocyanate (HDI) and ethylene glycol diglycidyl ether (EGDE), respectively. These gels markedly shrank in water upon heating. All the urethane-type gels began shrinking at 20 degrees C. On the other hand, the epoxy-types gels shrank at higher temperatures. The epoxy-type of HPC-L gel indicated the drastic shrinking at 38 degrees C, while the corresponding HPC gel showed the half volume at approximate 45 degrees C. Therefore, the epoxy-type of HPC-L gel is considered as a body-temperature responsive gel. These shrinking behaviors reflect the LCST of the original HP-derivatives in aqueous solution. The difference in the LCST and the temperature of gel shrinking between HPC-L and HPC were attributable to the hydrophobicity of the residual lignin.
  • M Nishida, Y Uraki, Y Sano
    BIORESOURCE TECHNOLOGY 88 1 81 - 83 2003年05月 [査読有り][通常論文]
     
    Lignin gels were prepared from acetic acid lignin by use of polyethylene glycol diglycidyl ether as cross-linker. The gels were found to swell in aqueous ethanol solution, in particular 50% (v/v) solution. In addition, they also swelled in alkaline solution and shrank upon heating. A literature search showed that investigation on gel swelling in aqueous ethanol has not been reported so far. Gels prepared from the cross-linker alone and its analogues did not show such swelling characteristics in aqueous ethanol. Therefore, the unique swelling property must be attributable to an intrinsic property of lignin. (C) 2002 Elsevier Science Ltd. All rights reserved.
  • T Kishimoto, H Tsuji, Y Uraki, Y Sano
    HOLZFORSCHUNG 57 2 181 - 188 2003年 [査読有り][通常論文]
     
    Atmospheric acetic acid pulp from Japanese white birch was bleached with 1-5% ozone with and without intermediate mild alkaline extraction. Concentrated acetic acid was a more effective bleaching media than water. Mild alkaline extraction of ozone-prebleached pulp was found to be very effective in delignification of the pulp and did not have any undesirable effects on pulp properties. A sufficiently delignified acetic acid pulp was obtained with inulti-stage ozone bleaching in Z(1)Z(2)Z(3) or Z(1)EZ(2)EZ(3) bleaching sequence with a total ozone consumption of 2.17% on oven-dry pulp. The pulp from a Z(1)EZ(2)EZ(3) sequence still contained 3.51% acetyl groups, which was 75% of the original amount of acetyl groups in unbleached acetic acid pulp.
  • J Nemoto, Y Uraki, Y Sano
    MOKUZAI GAKKAISHI 49 4 287 - 292 2003年 [査読有り][通常論文]
     
    Attempts were made to prepare board-shaped moldings for use as paper receptacles and structural materials. Composites of six kinds of isolated lignins and four kinds of waste paper were made by dry-forming and wet-forming methods. Board properties, such as flexural strength and water resistance, were examined with respect to component materials and to molding conditions. Excellent boards with the highest modulus of rupture (MOR) and the lowest water adsorption (WA) could be obtained from hardwood (H) and softwood (S) acetic acid lignin (AL) among the isolated lignins tested, and from waste newspaper among the waste paper. Technical lignins, such as kraft lignin and lignosulfonate, were not promising sources for boards because of low water resistance. The HAL-waste newspaper board showed maximal MOR when it composed of 15% of HAL. WA was reduced with increasing HAL content and molding temperature. Furthermore, MOR of boards was improved by partially replacing the lignin with either phenolic resin or biodegradable polyester. Comparing the forming processes, wet-formed boards had better properties than did dry-formed one; HAL 40% board with a density 1.4 g/cm(3) had an MOR of 68 MPa and WA of 4%. These results suggest that the AL acts as an adhesive for improving board strength. In addition, it gives the boards water resistance.
  • Uraki Yasumitsu, Miharu Yousuke, Funada Ryo, SANO Yoshihiro, MITSUHASHI Masaki, ITOYAMA Kohki, TANIBE Hiroaki
    繊維学会誌 56 10 482 - 486 The Society of Fiber Science and Technology, Japan 2000年10月10日 
    Alginate-blended rayon was prepared from a mixture of alginate and cellulose xantate in alkaline solution. Wide distribution of alginate in the whole fiber was revealed by scanning electron microscopy-energy dispersive X-ray microanalysis (SEM-EDX) and confocal laser scanning microscopy. The alginate blended in the rayon could not be removed by aqueous alkaline solution completely, suggesting that a part of the blended alginate formed tight complex with cellulose. The blended rayon had an excellent moisture sorption property such as a superior moisture sorption and a comparable heat of sorption to those of wool.
  • Y Uraki, S Kubo, H Kurakami, Y Sano
    HOLZFORSCHUNG 51 2 188 - 192 1997年 [査読有り][通常論文]
     
    Activated carbon fibers (ACF's) were prepared from acetic acid lignin-based carbon fibers by steam activation. The ACF had excellent properties, such as more rapid adsorption rate and higher iodine and methylene blue adsorption capacities, as compared to a commercially available activated carbon. The adsorption mechanism of ACF was quite different from that of activated carbon (AC), as supported by the micropore distribution profiles.
  • Satoshi Kubo, Yasumitsu Uraki, Yoshihiro Sano
    Holzforschung 50 2 144 - 150 1996年 [査読有り][通常論文]
     
    The thermal behavior of kraft lignin (KRL), periodate lignin (PIL), steam-exploded lignin (SEL) and acetic acid lignin (AAL), with emphasis on changes in volume upon heating, was investigated by thermomechanical analysis (TMA) in an attempt to evaluate the fusibility of lignin. All lignins underwent a glass transition but, with the exception of AAL, they all had infusible characteristics. The TMA curve for birch AAL (B-AAL) revealed two clear inflection points, assigned to the glass transition point (Tg) and the softening point (Ts) for transformation into a fluid liquid. Thus, only B-AAL among the lignins examined in this study had a fusion state. A fraction of B-AAL with almost the same weight-average relative molecular mass (Mw) as original B-AAL but with less polydispersity was found not to be transformed into a fused state. By contrast, fractions with lower relative molecular mass, namely, with Mw of less than 1,000, which accounted for 30% of AAL, had good fusibility. Therefore, the low-Mw fractions were responsible for the fusibility of B-AAL. Thermostable fusion states of acetylated KRL could not be confirmed by results of TMA and visual inspection. Thus, lignins could not be converted to fusible materials solely by the introduction of acetyl groups. Furthermore, from the results of TMA of fir AAL (F-AAL), which did not have a clear fusion state, it appeared that the fusibility of lignins was related to their molecular structures, for example, the extent of condensation of aromatic nuclei.
  • Y URAKI, S KUBO, N NIGO, Y SANO, T SASAYA
    HOLZFORSCHUNG 49 4 343 - 350 1995年 [査読有り][通常論文]
     
    Lignin fibers as precursors for carbon fibers were prepared by melt spinning from organosolv lignin (AWL), which was obtained from birch wood by aqueous acetic acid pulping at atmospheric pressure and used without any chemical modification. The spinnability of AWL was attributable to polydispersity of the lignin and to partial acetylation of hydroxyl groups during the pulping. Production of satisfactory lignin fibers was achieved by simple thermal treatment of lignin, followed by continuous spinning at a rate of more than 400m/min. The thermostabilization of thin (less than 30 mu m in diameter) and thick threads was achieved by heating to 250 degrees C at a rate of 0.5 degrees C/min in air and under oxygen stream, respectively. Carbonization of thermostable fibers was achieved by heating to 1,000 degrees C under nitrogen stream. The mechanical strength of the carbon fibers was found to be related to the diameter of fibers. Typical mechanical properties of carbon fibers from AWL were as follows: fiber diameter 14 +/- 1.0 mu m; elongation, 0.98 +/- 0.25%; tensile strength, 355 +/- 53 MPa; modulus of elasticity, 39.1 +/- 13.3 GPa. The carbon fibers derived from AWL can be classified as fibers of general performance grade.
  • Yasumitsu Uraki, Seiichi Tokura
    Journal of Macromolecular Science: Part A - Chemistry 25 10-11 1427 - 1441 1988年 [査読有り][通常論文]
     
    Among various divalent metal ions, calcium has been found to be adsorbed tightly onto carboxymethylated chitin. The adsorption was completed not only by induced carboxyl groups but also by the support of acetamide, as well as primary and secondary hydroxyl groups. Although the adsorption capacity for transition metal ions was enhanced appreciably by regeneration into fibrous form, only that of calcium ion, among alkali-earth metals, was at the same level as that of transition metals. Since little effect was shown on the adsorption of phenylalanine by the blocking of a-amino and a-carboxyl groups of L-Phe, and since D-Phe was so a little adsorbed, the chiral specific adsorption of phenylalanine might be supported by mediation of calcium ion and by the contribution of hydrophobicity of the P-phenyl group. © 1988, Taylor & Francis Group, LLC. All rights reserved.

MISC

  • 榊原義道, 長田晃汰, 浦木康光, 生方信, 重冨顕吾 日本木材学会大会研究発表要旨集(完全版)(CD-ROM) 70th 2020年
  • 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]
  • 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
  • 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]
  • Yasumitsu Uraki, Keiichi Koda Journal of Wood Science 61 (3) 447 -454 2015年 [査読有り][招待有り]
  • 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
  • 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
  • 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
  • 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]
  • 浦木康光, 幸田圭一 材料 61 (10) 867 -871 2012年 [査読有り][通常論文]
  • Masato Ogawa, Teuku B. Bardant, Yasutaka Sasaki, Yutaka Tamai, Seiichi Tokura, Yasumits Uraki BIORESOURCES 7 (1) 236 -245 2012年 [査読無し][通常論文]
     
    Activated carbons (ACs) were prepared from biomass of Borneo island (wood charcoal, peat, and coconut husk) by using an electricity-free furnace, of which the energy source was exclusively wood charcoal. This furnace was comprised of two parts, an inner vessel equipped with water inlet for steam activation and an outer shell as a heating part for the inner vessel. The inside temperature of the inner vessel was able to reach over 1000 degrees C. Peat and wood charcoal were converted to AC by carbonization followed by steam activation, and the specific BET surface areas of resultant ACs were 889 m(2)/g and 749 m(2)/g, respectively. A mobile apparatus for water purification was newly designed and fabricated with the resultant AC, together with a white quartz sand, which is called keranggas in Kalimantan. The CODOH of both polluted creek water by the University of Palangka Raya and Kahayan River water were remarkably decreased by the purification with the designed apparatus from 20.0 mgO/L to 0.93 mgO/L, and 18.2 mgO/L to 0.74 mgO/L, respectively. Thus, the newly designed furnace and purification apparatus were shown to be highly effective tools to produce a promising agent for water purification and to produce clarified water without use of electricity, respectively.
  • 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 [査読無し][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.
  • 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]
  • 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
  • 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
  • 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
  • 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
  • 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
  • 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 [査読無し][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.
  • ホットメルトするリグニン
    ホットメルト材料および装置、製品の最新技術と使い方ノウハウ 78 -82 2011年 [査読無し][通常論文]
  • Keiichi Koda, Satoshi Kubo, Yasumitsu Uraki ACS Symposium Series 1067 261 -277 2011年 [査読無し][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.
  • 浦木 康光 表面科学 : hyomen kagaku = Journal of the Surface Science Society of Japan 31 (6) 301 -306 2010年06月10日
  • 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
  • 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
  • 浦木康光, 田崎裕佳, 玉井裕, 山本貞明, 藪浩, 下村政嗣 高分子学会予稿集(CD-ROM) 59 (2 Disk1) 2010年
  • Yasumitsu Uraki, Chinatsu Matsumoto, Takuro Hirai, Yutaka Tamai, Makiko Enoki, Hiroshi Yabu, Masaru Tanaka, Masatsugu Shimomura JOURNAL OF WOOD CHEMISTRY AND TECHNOLOGY 30 (4) 348 -359 2010年 [査読無し][通常論文]
     
    We have already fabricated honeycomb-patterned cellulosic films with cellulose I and II polymorphisms as a basal framework in order to create an artificial woody cell wall.[1,2] The adsorption of an isolated lignin, acetic acid lignin (AL), was attempted onto the honeycomb films not only to develop materials further mimicking the cell wall but also to elucidate the mechanical effect of isolated lignin on the tensile strength of the cellulosic architecture. The tensile strengths of honeycomb-patterned cellulosic films were improved by the AL adsorption. Although the cellulosic films without lignin weakened under high moisture content conditions as compared with those under the low content conditions, the lignin-adsorbed cellulosic film maintained significant tensile strength even under the high content conditions. This result suggests that lignin contributes to reinforce the mechanical strength of cellulose framework, in particular high moisture conditions.
  • Yuka Tasaki, Yasumitsu Uraki, Keiichi Koda, Sadaaki Yamamoto, Hiroshi Yabu, Masatsugu Shimomura RESEARCH PROGRESS IN PAPER INDUSTRY AND BIOREFINERY (4TH ISETPP), VOLS 1-3 3 1465 -1468 2010年 [査読無し][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.
  • Chihiro Oikawa, Keiichi Koda, Yasumitsu Uraki, Masanobu Nojiri, Tatsuhiko Yamada, Kiyohiko Igarashi RESEARCH PROGRESS IN PAPER INDUSTRY AND BIOREFINERY (4TH ISETPP), VOLS 1-3 2 1306 -1309 2010年 [査読無し][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.
  • Yasumitsu Uraki, Keiichi Koda, Takao Kishimoto, Satoshi Kubo RESEARCH PROGRESS IN PAPER INDUSTRY AND BIOREFINERY (4TH ISETPP), VOLS 1-3 1 315 -318 2010年 [査読無し][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.
  • 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 [査読無し][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 10% 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. © 2010, The Japan Wood Research Society. All rights reserved.
  • Takao Kishimoto, Wakako Chiba, Kaori Saito, Kazuhiko Fukushima, Yasumitsu Uraki, Makoto Ubukata JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 58 (2) 895 -901 2010年01月 [査読無し][通常論文]
     
    Several kinds of natural woods and isolated lignins with various syringyl to guaiacyl (S/G) ratios were subjected to thioacidolysis followed by Raney nickel desulfuration to elucidate the relationships between the S/G ratio and the interunit linkage types of lignin. Furthermore, enzymatic dehydrogenation polymers (DHP) were produced by the Zutropf (gradual monolignol addition) method from mixtures of various ratios of coniferyl alcohol and sinapyl alcohol. The analysis of DHPs and natural wood lignins exhibited basically a similar tendency. The existence of both syringyl and guaiacyl units is effective for producing higher amounts of beta-O-4 and 4-O-5 structures, but it lowers the total amount of cinnamyl alcohol and aldehyde end groups. The relative frequency of the beta-beta structure increased, whereas that of beta-5 and 5-5 structures decreased with increasing syringyl units.
  • Harumi Homma, Satoshi Kubo, Tatsuhiko Yamada, Keiichi Koda, Yasuyuki Matsushita, Yasumitsu Uraki JOURNAL OF WOOD CHEMISTRY AND TECHNOLOGY 30 (2) 164 -174 2010年 [査読無し][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.
  • Teuku Beuna Bardant, Chihiro Oikawa, Masanobu Nojiri, Keiichi Koda, Yanni Sudiyani, Tatsuhiko Yamada, Yasumitsu Uraki MOKUZAI GAKKAISHI 56 (6) 420 -426 2010年 [査読無し][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.
  • Takao Kishimoto, Yasumitsu Uraki, Makoto Ubukata, Masahiro Hamada, Noriyuki Nakajima ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY 237 2009年03月 [査読無し][通常論文]
  • Yasumitsu Uraki, Yutaka Tamai, Masato Ogawa, Sampang Gaman, Seiichi Tokura BIORESOURCES 4 (1) 205 -213 2009年02月 [査読無し][通常論文]
     
    Peat with an approximate 60% carbon content collected in the suburbs of Palangka Raya, Indonesia, was carbonized, followed by activation with steam in an electric furnace. The resultant activated carbon (AC) had ca. 900 m(2)/g of BET surface area and 1000 mg/g of iodine adsorption. This performance implies that this AC can be used as an adsorbent for environmental purification. We had a carbonizing furnace manufactured in Palangka Raya, which did not require electric power. Some AC having 350 mg/g of iodine adsorption was obtained by using this furnace. Although the adsorption ability was much lower than that of commercially available AC, the AC achieved significant decoloration and decrease in chemical oxygen demand of polluted river water. Thus, this article demonstrated the potential of tropical peat soil as a source of AC.
  • 浦木康光, 玉井裕, 平井卓郎, 藪浩, 田中賢, 下村政嗣 高分子学会予稿集(CD-ROM) 58 (2 Disk1) 2009年
  • CRYSTALLINITY OF POLYETHYLENE GLYCOL CHAINS ANCHORED ON LIGNIN MOLECULES
    15th International Symposium of Wood, Fiber and Pulping Chemistry P-170 2009年 [査読無し][通常論文]
  • CONVERSION OF ACETIC ACID LIGNIN TO A NONIONIC POLYMERIC SURFACTANT
    15th International Symposium of Wood, Fiber and Pulping Chemistry P-163 2009年 [査読無し][通常論文]
  • CLEAVAGE OF ETHEREAL BONDS IN LIGNIN STRUCTURE WITH ALUMINIUM IODIDE (III) -FORMATION OF CATECHOL MOIETIES FROM GUAIACYL UNITS
    15th International Symposium of Wood, Fiber and Pulping Chemistry P-042 2009年 [査読無し][通常論文]
  • INFLUENCE OF SYRINGYL-TOGUAIACYL RATIO ON THE STRUCTURE OF LIGNIN
    15th International Symposium of Wood, Fiber and Pulping Chemistry P-002 2009年 [査読無し][通常論文]
  • CREATION OF ARTIFICIAL CELL WALL BY USING HONEYCOMB-PATTERNED CELLULOSE.
    Proceedings of International Conference on Pulping, papermaking and Biotechnology O-054 2009年 [査読無し][通常論文]
  • URAKI Yasumitsu, KISHIMOTO Takao, KODA Keiichi, FUKUSHIMA Kazuhiko, KANAZAWA Yoshie . Journal of Wood Chemistry and Technology 29 (2) 178 -190 2009年 [査読無し][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.
  • Takao Kishimoto, Yasumitsu Uraki, Makoto Ubukata ORGANIC & BIOMOLECULAR CHEMISTRY 6 (16) 2982 -2987 2008年08月 [査読無し][通常論文]
     
    We describe the synthesis and NMR spectroscopic analysis of three artificial lignin polymers containing only the beta-O-4 substructure: syringyl-type homopolymer, p-hydroxyphenyl-type homopolymer and guaiacyl/syringyl-type heteropolymer. Using gel permeation chromatography, the weight-average degree of polymerization (DPw) of the three polymers was determined as 19.2. 38.6, and 13.9, respectively. The polymers were prepared based on the synthetic methodology of guaiacyl-type homopolymer, and were fully characterized using H-1-, C-13-, and H-1-C-13 NMR spectroscopy of the acetylated and non-acetylated forms. The spectra of guaiacyl/syringyl-type heteropolymers were in good agreement with those of the beta-O-4 substructure of milled wood lignin obtained from the hardwood of Japanese white birch.
  • Md. Ibrahim H. Mondal, Yasumitsu Uraki, Makoto Ubukata, Koki Itoyama CELLULOSE 15 (4) 581 -592 2008年08月 [査読無し][通常論文]
     
    The influence of treating cotton fibres with several amines on the mechanical properties, moisture sorption ability before and after graft polymerization, and on graft yields for various water-soluble and water-insoluble vinyl monomers were analysed. As compared to water, the treatment with amines, ethylenediamine (EDA) in particular, resulted in a decrease in the crystallinity and tensile strength of the cotton fibres, and an increase in the moisture sorption. The graft yields of amine-treated cotton fibres using water-soluble monomers, acrylic acid (AA), methacrylic acid (MAA) and acrylamide (AM) were greater than those observed for water-treated cotton fibres, whereas the graft yields using water-insoluble monomers, methyl acrylate (MA), methyl methacrylate (MMA) and vinyl acetate (VA) were lower. The moisture sorption ability was improved by the graft polymerization with water-soluble monomers. The improvement was enhanced for MA and MAA by treatment with sodium hydroxide to form the corresponding sodium carboxylate derivatives. The tensile strength of EDA-treated cotton was slightly reduced by grafting, while that of the water-activated cotton yarn was barely changed. These results suggest that the graft polymerization of amine-treated cotton fibres with certain vinyl monomers increased the moisture sorption ability without resulting in increased fibre rigidity.
  • 榎牧子, 佐藤道佑, 金田航大, 関山亮太, 中川明子, 浦木康光, 兼廣春之 日本水産学会誌 74 (4) 688 -693 2008年07月 [査読無し][通常論文]
     
    Sea algal paste was obtained by soaking brown alga in sodium carbonate solution and was found to have a flocculating effect on muddy water in the presence of calcium chloride as a cross linking agent. This technique does not involve the extraction of alginic acid and production of secondary waste. The sea alga paste obtained by soaking in sodium carbonate solution for five minutes at 70°C demonstrated an excellent flocculating effect, which did not depend on the density of muddy water. Stirring time after mixing all ingredients was found to affect the flocculation. Furthermore, the amount of sea alga paste and calcium chloride also influenced the coagulating effect.
  • Makiko Enoki, Michisuke Sato, Kodai Kaneda, Ryota Sekiyama, Akiko Nakagawa, Yasumitsu Uraki, Haruyuki Kanehiro NIPPON SUISAN GAKKAISHI 74 (4) 688 -693 2008年07月 [査読無し][通常論文]
     
    Sea algal paste was obtained by soaking brown alga in sodium carbonate solution and was found to have a flocculating effect on muddy water in the presence of calcium chloride as a cross linking agent. This technique does not involve the extraction of alginic acid and production of secondary waste. The sea alga paste obtained by soaking in sodium carbonate solution for five minutes at 70 degrees C demonstrated an excellent flocculating effect, which did not depend on the density of muddy water. Stirring time after mixing all ingredients was found to affect the flocculation. Furthermore, the amount of sea alga paste and calcium chloride also influenced the coagulating effect.
  • 浦木康光, 生方信, MONDAL Md, Ibrahim H, 糸山光紀 繊維学会予稿集 63 (1/2) 110 2008年06月18日 [査読無し][通常論文]
  • 本間春海, 浦木康光, 生方信, 久保智史, 山田竜彦 繊維学会予稿集 63 (1/2) 128 2008年06月18日 [査読無し][通常論文]
  • Yasumitsu Uraki, Md Mondal H. Ibrahim, Koki Itoyama, Makoto Ubukata ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY 235 2008年04月 [査読無し][通常論文]
  • 三橋進也, 岸本崇生, 浦木康光, 生方信 日本農芸化学会大会講演要旨集 2008 168 2008年03月05日 [査読無し][通常論文]
  • Shinya Mitsuhashi, Takao Kishimoto, Yasumitsu Uraki, Takashi Okamoto, Makoto Ubukata Bioorganic and Medicinal Chemistry 16 (5) 2645 -2650 2008年03月 [査読無し][通常論文]
     
    Human immunodeficiency virus type 1 (HIV-1) is a cytopathic retrovirus and the primary etiological agent of acquired immunodeficiency syndrome (AIDS) and related disorders. In cells chronically infected with HIV-1, nuclear factor-kappa B (NF-kappa B) activation by external stimuli such as tumor necrosis factor alpha (TNF alpha) augments replication of HIV-1. NF-kappa B involves in many diseases such as inflammation, cancer, and. Crohn's disease. In this paper, we exhibit that (i) HIV-1 gene expression was inhibited by lignin, (ii) fraction of small molecular mass in HBS lignin (less than 0.5 kDa) had stronger inhibitory effects than large molecular mass (more than 1.3 kDa), (iii) lignin also inhibited activation of NF-kappa B induced by TNF alpha, (iv) among six lignin dimer-like compounds, compound 6 containing beta-5 bond has more potent inhibitory activity than compounds 1, 2, 3, 4 and 5, which contain beta-1, beta-O-4, 5-5, or beta-beta structural units. These results suggested that small molecules of lignin inhibit HIV-1 replication through suppression of HIV-1 transcription from LTR including activation via NF-kappa B. Low molecular lignin may be a beneficial material or drug leads as a new class for AIDS and NF-kappa B-related diseases. (C) 2008 Published by Elsevier Ltd.
  • 松本千夏, 浦木康光, 平井卓郎, 生方信, 藪浩, 田中賢, 下村政嗣 高分子学会北海道支部研究発表会講演要旨集 42nd 15 2008年01月29日 [査読無し][通常論文]
  • 本間春海, 浦木康光, 生方信, 山田竜彦, 久保智史 日本木材学会大会研究発表要旨集(完全版)(CD-ROM) 58th ROMBUNNO.L19-0945 2008年 [査読無し][通常論文]
  • 松本千夏, 浦木康光, 平井卓郎, 玉井裕, 生方信 日本木材学会大会研究発表要旨集(完全版)(CD-ROM) 58th ROMBUNNO.K18-1645 2008年 [査読無し][通常論文]
  • Polymerization of coniferyl alcohol by chain reaction. Another reaction for lignin formation.
    Cellulose Chemistry and Technology 41 (9-10) 505 -509 2008年 [査読無し][通常論文]
  • Harumi Homma, Satoshi Kubo, Tatsuhiko Yamada, Yasuyuki Matsushita, Yasumitsu Uraki JOURNAL OF WOOD CHEMISTRY AND TECHNOLOGY 28 (4) 270 -282 2008年 [査読無し][通常論文]
     
    Acetic acid lignin (AL), one of the organosolv lignins, was modified by polyoxyethylation using commercially available polyethylene glycol diglycidylethers (PEGDE) having various chain lengths in order to generate novel nonionic polymeric surfactants. AL could be converted to the amphiphile by modifying with PEGDE (PEGDE-AL) having more than 9 of the ethylene oxide (EO) repeating units. Although the surface activities of PEG and AL were very limited, PEGDE-AL did strongly depress surface tension of water, and showed clear critical micelle concentrations (CMC). The CMC value of PEGDE-AL could be comparable to a commercial anionic lignin surfactant, lignosulfonate. The surface activity of AL amphiphile was further improved by modification with monoepoxides, ethoxy-(2-hydroxy)-propoxy-polyethylene glycol glycidylether (EPEGGE). The surface tension of water was depressed by the addition of the EPEGGE-AL to the same level as Triton X-100, which is a commercial PEG-based nonionic surfactant, although there is still room for improvement in CMC value. The hydrophile-lipophile balance (HLB) of these AL amphiphiles was in the range of 11-14, and significant biodegradation was observed. These results suggest that the AL amphiphiles can be used as emulsifier and detergent.
  • KISHIMOTO Takao, URAKI Yasumitsu, UBUKATA Makoto Journal of Wood Chemistry and Technology 28 (2) 97 -105 2008年 [査読無し][通常論文]
     
    Guaiacyl, syringyl, and p-hydroxyphenyl-type bromoacetophenone derivatives were synthesized as the starting materials for beta -O-4 type artificial lignin polymers. They were prepared from 4-hydroxyacetophenone instead of 4-hydroxybenzaldehyde, which was used in the previous investigations. The new route required 4 reaction steps. Overall yields of the monomers were 60, 79, and 68%, respectively.
  • 岸本崇生, 浦木康光, 生方信 リグニン討論会講演集 52nd 86 -89 2007年10月31日 [査読無し][通常論文]
  • 金澤香枝, 浦木康光, 生方信, 岸本崇生 リグニン討論会講演集 52nd 90 -93 2007年10月31日 [査読無し][通常論文]
  • 鈴木啓介, 浦木康光, 生方信 リグニン討論会講演集 52nd 152 -153 2007年10月31日 [査読無し][通常論文]
  • 杉山祐介, 浦木康光, 生方信, 岸本崇生 日本木材学会北海道支部講演集 (39) 61 -64 2007年10月22日 [査読無し][通常論文]
  • 松本千夏, 浦木康光, 生方信, 玉井裕, 平井卓郎, 藪浩, 田中賢, 下村政嗣 日本木材学会北海道支部講演集 (39) 31 -34 2007年10月22日 [査読無し][通常論文]
  • 岸本崇生, 浦木康光, 生方信 天然有機化合物討論会講演要旨集 49th 575 -580 2007年08月24日 [査読無し][通常論文]
  • 松本千夏, 浦木康光, 生方信, 平井卓郎, 藪浩, 田中賢, 下村政嗣 セルロース学会年次大会講演要旨集 14th 77 2007年07月15日 [査読無し][通常論文]
  • Yasumitsu Uraki, Junji Nemoto, Hiroyuki Otsuka, Yutaka Tamai, Junji Sugiyama, Takao Kishimoto, Makoto Ubukata, Hiroshi Yabu, Masaru Tanaka, Masatsugu Shimomura CARBOHYDRATE POLYMERS 69 (1) 1 -6 2007年05月 [査読無し][通常論文]
     
    Bacterial cellulose (BC)-producing bacterium, Gluconacetobacter xylinus (ATCC53582), was found to move along linear microgrooves of a stripe-patterned cellulosic scaffold. On the basis of this finding, fabrication of honeycomb-patterned BC was attempted by controlling the bacterial movement using a agarose film scaffold with honeycomb-patterned grooves (concave type). The patterned agarose film was prepared by three steps. The first was transcription of a honeycomb-patterned polycaprolactone film template with polydimethyl siloxane. When the bacteria were cultured on the scaffold under atmospheric conditions, only bacterial proliferation was observed. Honeycomb-patterned BC was obtained when cultured under a humid CO2 atmosphere. Electron diffraction and polarized microscopic observation showed that the patterned BC comprised of the well defined cellulose lot microfibrils. As another attempt to fabricate honeycomb-patterned BC, the bacteria were cultured on the patterned cellulose and agarose film with convex type of honeycomb. This culture yielded no honeycomb-patterned BC. Therefore, concave type honeycomb scaffold is more suitable to fabricate honeycomb-patterned BC. (c) 2006 Elsevier Ltd. All rights reserved.
  • 岸本崇生, 浦木康光, 生方信 日本農芸化学会大会講演要旨集 2007 105 2007年03月05日 [査読無し][通常論文]
  • 鈴木啓介, 浦木康光, 岸本崇生, 生方信 高分子学会北海道支部研究発表会講演要旨集 41st 38 2007年02月06日 [査読無し][通常論文]
  • Yasumitsu Uraki SEN-I GAKKAISHI 63 (1) P18 -P22 2007年01月 [査読無し][通常論文]
  • 杉山祐介, 浦木康光, 生方信, 岸本崇生 日本木材学会大会研究発表要旨集(完全版)(CD-ROM) 57th L08-0945 2007年 [査読無し][通常論文]
  • Yasumitsu Uraki, Atsushi Nakamura, Takao Kishimoto, Makoto Ubukata JOURNAL OF WOOD CHEMISTRY AND TECHNOLOGY 27 (1) 9 -21 2007年 [査読無し][通常論文]
     
    Interactions of hemicelluloses, xylan and glucomannan, with monolignols, coniferyl alcohol and sinapyl alcohol, and their glucosides, coniferin and syringin, were investigated by surface plasmon resonance analysis. Hemicelluloses with different aldehyde contents, prepared by sodium periodate oxidation, were immobilized onto carboxymethyl-dextran-coated gold plates by reductive amination. The interaction of the hemicelluloses with monolignols was evaluated as weight gain of the hemicelluloses at neutral pH. Both hemicelluloses adsorbed the monolignols in much larger amounts than the corresponding glucosides. The adsorption tendency was independent of aldehyde content. These results suggest the hemicelluloses have higher affinities to the aglycons than the glucosides. Thus, the interactions of the hemicelluloses with monolignols are primarily the result of hydrophobic interactions. However, binding constants were not estimated because of the low solubility of the monolignols in the aqueous buffered solution.
  • 千葉和歌子, 岸本崇生, 浦木康光, 生方信, 齋藤香織, 福島和彦 日本木材学会北海道支部講演集 (38) 35 -38 2006年10月31日 [査読無し][通常論文]
  • 杉山祐介, 岸本崇生, 浦木康光, 生方信, 久保智史 日本木材学会北海道支部講演集 (38) 39 -42 2006年10月31日 [査読無し][通常論文]
  • 三橋進也, 岸本崇生, 浦木康光, 生方信 リグニン討論会講演集 51st 112 -115 2006年10月10日 [査読無し][通常論文]
  • 宮田直紀, 荻野晋一, 浦木康光, 生方信 リグニン討論会講演集 51st 116 -119 2006年10月10日 [査読無し][通常論文]
  • 岸本崇生, 浦木康光, 生方信 リグニン討論会講演集 51st 212 -213 2006年10月10日 [査読無し][通常論文]
  • 松本千夏, 浦木康光, 岸本崇生, 生方信, 藪浩, 田中賢, 下村政嗣 セルロース学会年次大会講演要旨集 13th 32 -33 2006年07月01日 [査読無し][通常論文]
  • Y Uraki, T Imura, T Kishimoto, M Ubukata CELLULOSE 13 (3) 225 -234 2006年06月 [査読無し][通常論文]
     
    The lower critical solution temperature (LCST) of hydroxypropylcellulose bearing lignin (HPC-L) prepared from unbleached pulp depends on the amount of residual lignin. An HPC-L gel having thermal properties reflective of original HPC-L was prepared using ethyleneglycol diglycidylether as a crosslinker, as previously reported [Uraki et al. (2004) Carbohydr. Polym. 58:123-130], and the volume transition temperature was detected as an endothermic peak by differential scanning calorimetry (DSC). The adsorption and release behavior of the guest molecules to/from this gel was then examined. When the adsorption of cationic and anionic guests was compared, cationic methylene blue (MB) was adsorbed in larger amounts than anionic methyl orange (MO). In addition, MB adsorption into the HPC-L gel was greater than MB adsorption into the HPC gel prepared from commercially available HPC. This suggests that residual lignin affects the adsorption of organic dyes. Significant differences were not observed with respect to the release of MB from HPC-L at 38 degrees C and lower temperatures. In the adsorption of surfactants, marked adsorption at around the critical micelle concentration of the ionic surfactants and gel swelling were observed. Such swelling did not occur in the aqueous nonionic surfactant solution, although the nonionic surfactant was adsorbed into the gel. Gel swelling may have been caused by the electrostatic repulsion of the ionic surfactants adsorbed onto the polymer chains within the gel structure.
  • Y Uraki, J Nemoto, Y Sano JOURNAL OF WOOD SCIENCE 52 (2) 163 -166 2006年04月 [査読無し][通常論文]
     
    We developed a novel method for preparation of microcasts of wood with silicone elastomer (polydimethylsiloxane; PDMS). PDMS was so flexible and elastic that it was possible to isolate the microcasts by simply pulling them out of the mold without digesting the cell wall after the resin was cured for 2 days at room temperature. The casts of some cell wall sculptures, such as spiral thickenings and bordered pits, had high fidelity. By contrast, the casts of distinctly bordered pits and tails of vessel elements were often deformed or broken. Bars of scalariform perforation plates were always torn and remained in the resin casts. The microcast preparation using PDMS is useful for easy investigation of cell wall sculptures. It might be also useful for microfractography of bars of scalariform perforation plates.
  • 岸本崇生, 浦木康光, 生方信 日本農芸化学会大会講演要旨集 2006 16 2006年03月05日 [査読無し][通常論文]
  • 岸本崇生, 重松幹二, 浦木康光, 生方信 日本木材学会大会研究発表要旨集(完全版)(CD-ROM) 56th 2006年
  • 浦木康光, 松本千夏, 岸本崇生, 生方信, 藪浩, 田中賢, 下村政嗣 日本農芸化学会北海道支部・日本土壌肥料学会北海道支部・日本生物工学会北日本支部・日本応用糖質科学会北海道支部・北海道農芸化学協会合同学術講演会講演要旨 2006 13 2006年 [査読無し][通常論文]
  • Yasumitsu Uraki, Yuriko Usukura, Takao Kishimoto, Makoto Ubukata HOLZFORSCHUNG 60 (6) 659 -664 2006年 [査読無し][通常論文]
     
    A lignin-carbohydrate complex (LCC) fraction isolated from the residue of milled wood lignin extraction of birch was found to form self-aggregates in water. The aggregates had relatively strong hydrophobic domains, comparable to the hydrophobicity of 80% ethanol. Dynamic light scattering analysis showed that the aggregates were transformed into small particles by sonication with a number-average diameter of 43.7 +/- 9.6 nm, and were stable in water. The surface pressure (pi)-surface area (A) profile showed that the LCC also formed a monolayer on the water surface. Based on these results, we suggest that the LCC is amphiphilic in nature, despite its insolubility in low-polarity organic solvents.
  • T Kishimoto, Y Uraki, M Ubukata ORGANIC & BIOMOLECULAR CHEMISTRY 4 (7) 1343 -1347 2006年 [査読無し][通常論文]
     
    An artificial lignin polymer containing only the beta-O-4 substructure was synthesized. The procedure consists of two key steps: 1) polycondensation of a brominated monomer by aromatic Williamson reaction; and 2) subsequent reduction of the carbonyl polymer. C-13-NMR and HMQC spectra of the polymer were consistent with beta-O-4 substructures in milled wood lignin isolated from Japanese fir wood. The weight average degree of polymerization (DPw) ranged from 19.5 to 30.6, which is comparable to enzymatically synthesized artificial lignin from p-hydroxycinnamyl alcohols ( dehydrogenation polymer, DHP) and some isolated lignins. Using this new lignin model polymer, it will now be possible to reinvestigate the properties and reactivity of the main lignin structure in terms of its polymeric character.
  • 重冨顕吾, 中村淳, 岸本崇生, 浦木康光, 生方信 日本木材学会北海道支部講演集 (37) 17 -20 2005年10月21日 [査読無し][通常論文]
  • 浦木康光, 井村健, 岸本崇生, 生方信 リグニン討論会講演集 50th 46 -49 2005年10月07日 [査読無し][通常論文]
  • 生方信, 植木飛鳥, 三橋進也, 岸本崇生, 浦木康光, 藤田進一郎 リグニン討論会講演集 50th 50 -53 2005年10月07日 [査読無し][通常論文]
  • 岸本崇生, 浦木康光, 生方信 リグニン討論会講演集 50th 146 -147 2005年10月07日 [査読無し][通常論文]
  • 浦木康光, 大塚裕之, 玉井裕, 佐野雄三, 岸本崇生, 生方信, 杉山淳司, 田中賢, 藪浩, 下村政嗣 セルロース学会年次大会講演要旨集 12th 89 -90 2005年07月11日 [査読無し][通常論文]
  • 浦木康光, 大塚裕之, 生方信, 薮浩, 田中賢, 下村政嗣 高分子学会予稿集(CD-ROM) 54 (1 Disk1) 2M14 2005年05月10日 [査読無し][通常論文]
  • 大塚裕之, 浦木康光, 根本純司, 岸本崇生, 生方信, 薮浩, 田中賢, 下村政嗣 日本農芸化学会大会講演要旨集 2005 159 2005年03月05日 [査読無し][通常論文]
  • 岸本崇生, 浦木康光, 生方信 日本農芸化学会大会講演要旨集 2005 21 2005年03月05日 [査読無し][通常論文]
  • 臼倉ゆり子, 浦木康光, 植木飛鳥, 岸本崇生, 生方信 日本農芸化学会大会講演要旨集 2005 194 2005年03月05日 [査読無し][通常論文]
  • 中村淳, 浦木康光, 岸本崇生, 生方信 日本木材学会北海道支部講演集 (37) 2005年
  • 中村淳, 浦木康光, 岸本崇生, 生方信 リグニン討論会講演集 50th 2005年
  • Investigation on interaction of hemicelluloses with monolignols using surface plasmon resonance
    Proceedings of 13th International Symposium on Wood, Fiber and Pulping Chemistry 3 277 -281 2005年 [査読無し][通常論文]
  • Preparation of intelligent gels with a body-temperature response from unbleached acetic acid pulp.
    Proceedings of 13th International Symposium on Wood, Fiber and Pulping Chemistry 2 545 -551 2005年 [査読無し][通常論文]
  • Preparation and chracterizaton of fiberboards from waste papers bonded by lignin.
    Proceedings of presimposium of 13th International Symposium on Wood, Fiber and Pulping Chemistry (1) 159 -163 2005年 [査読無し][通常論文]
  • T. Kishimoto, Y. Uraki and M. Ubukata: Easy synthesis of -O-4 type lignin related polymers. Org. Biomol. Chem., 3, 1067-1073 (2005).*
    2005年 [査読無し][通常論文]
  • J. Nemoto, Y. Uraki, T. Kishimoto, Y. Sano, R. Funada, N. Obata, H. Yabu, M. Tanaka, M. Shimomura: Production of mesocopically patterned cellulose film. Bioresource Tech., 96, 1955-1958 (2005).*
    2005年 [査読無し][通常論文]
  • Y Uraki, J Nemoto, K Yanaga, A Koizumi, T Hirai JOURNAL OF WOOD SCIENCE 51 (6) 589 -594 2005年 [査読無し][通常論文]
     
    Y. Uraki , J. Nemoto, K. Yanaga, A. Koizumi and T. Hirai: Preparation of board-like moldings from Composites of isolated lignins and waste paper II: Effect of inorganic salts addition on board performance and evaluation of practical use of MDF. J. Wood Sci. 51, 589-594 (2005)*
  • “森林の科学-森林生態系科学入門-”<中村太士、小池孝良編著>
    朝倉書店 2005年 [査読無し][通常論文]
  • Y Uraki, T Imura, T Kishimoto, M Ubukata CARBOHYDRATE POLYMERS 58 (2) 123 -130 2004年11月 [査読無し][通常論文]
     
    Hydroxypropylcellulose bearing lignin (HPC-L) prepared from softwood by the atmospheric acetic acid pulping followed by derivatization showed the lower critical solution temperature (LCST) of approximate 38degreesC in 2% aqueous solution, which were 5degrees lower than that of pure HPC with a similar molecular mass to HPC-L. Two types, urethane and epoxy, of chemical gels were prepared from HPC-L and HPC using hexamethylene diisocyanate and polyethylene glycol diglycidyl ether as crosslinkers, respectively. The urethane-type gels from both HPC's have undergone shrinking at less than 20degreesC. This thermoresponse of the gels did not reflect LCST of the sources. Such low temperature shrinking was brought about by the hydrophobicity of crosslinker. On the other hand, the epoxy-type gels showed a very similar volume transition temperature (VTT) upon shrinking to LCST; the epoxy-type HPC-L gel showed VTT at 38degreesC, while the corresponding HPC gel had VTT at 46degreesC. This difference in VTT as well as LCST was attributable to hydrophobicity of lignin dangled to HPC. Thus, the body temperature-responsive gel can be prepared from HPC-L with the water-soluble crosslinker. (C) 2004 Elsevier Ltd. All rights reserved.
  • 井村健, 浦木康光, 岸本崇生, 生方信 日本木材学会北海道支部講演集 (36) 35 -38 2004年10月28日 [査読無し][通常論文]
  • 岸本崇生, 浦木康光, 生方信 リグニン討論会講演集 49th 21 -24 2004年10月20日 [査読無し][通常論文]
  • 田村裕, 戸倉清一, 山本克憲, 国安春子, 浦木康光, 生方信 高分子学会予稿集(CD-ROM) 53 (2 Disk1) 2PF160 2004年09月01日 [査読無し][通常論文]
  • 田村裕, 真田陽子, 戸倉清一, 浦木康光, 生方信 セルロース学会年次大会講演要旨集 11th 9 -10 2004年07月01日 [査読無し][通常論文]
  • 根本純司, 浦木康光, 岸本崇生, 生方信, 薮浩, 田中賢, 下村政嗣 セルロース学会年次大会講演要旨集 11th 105 2004年07月01日 [査読無し][通常論文]
  • Y Usukura, Y Uraki, T Kishimoto, M Ubukata, T Hiraoki ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY 227 U311 -U311 2004年03月 [査読無し][通常論文]
  • 浦木康光, 中村淳, 岸本崇生, 生方信 リグニン討論会講演集 49th 2004年
  • 臼倉ゆり子, 植木飛鳥, 浦木康光, 岸本崇生, 生方信 リグニン討論会講演集 49th 2004年
  • 浦木康光, 井村健, 臼倉ゆり子, 岸本崇生, 生方信 日本学術会議材料研究連合講演会講演論文集 48th 2004年
  • リグニンとセルロース系バイオマスから調製した種々の成形活性炭
    木質炭化学会誌 1 (1) 23 -29 2004年 [査読無し][通常論文]
  • T Kishimoto, A Ueki, H Takamori, Y Uraki, M Ubukata HOLZFORSCHUNG 58 (4) 355 -362 2004年 [査読無し][通常論文]
     
    In order to investigate the delignification mechanism during high-boiling solvent (HBS) pulping, softwood HBS lignin samples from todo fir (Abies sachalinensis) were analyzed by H-1-C-13 correlation NMR spectroscopy (HMQC). Nine lignin model compounds that may represent the substructures in HBS lignin were prepared. The H-1 and C-13 NMR spectral data were compared with HBS lignin samples. The HMQC spectra of HBS lignin samples showed the disappearance of beta-O-4 structures. Introduction of a pulping solvent into lignin was plainly observed with new signals in aliphatic regions. Only the erythro beta-1 structure was detected in softwood milled wood lignin from todo fir by HMQC spectra. The beta-1 structure was very reactive and probably produced the stilbene structure. The beta-beta and beta-5 structures remained in HBS lignin. The 4-O-5 structure was successfully detected by HMQC spectra, and it was found to be stable under the conditions used.
  • T. Imura, Y. Uraki, T. Kishimoto and M. Ubukata: Thermoresponsive gels prepared from hydroxypropylated unbleached pulp. Proceeding of The 2nd International Symposium on Technologies of Pulping, Papermaking and Biotechnology on Fiber Plants, 595-528 (20・・・
    2004年 [査読無し][通常論文]
     
    T. Imura, Y. Uraki, T. Kishimoto and M. Ubukata: Thermoresponsive gels prepared from hydroxypropylated unbleached pulp. Proceeding of The 2nd International Symposium on Technologies of Pulping, Papermaking and Biotechnology on Fiber Plants, 595-528 (2004).
  • A. Nakamura, Y. Uraki, T. Kishimoto and M. Ubukata: Analysis of adsorption behavior of monolignols onto hemicellulose using surface plasmon resonance. Proceeding of The 2nd International Symposium on Technologies of Pulping, Papermaking and Biotechnolo・・・
    2004年 [査読無し][通常論文]
     
    A. Nakamura, Y. Uraki, T. Kishimoto and M. Ubukata: Analysis of adsorption behavior of monolignols onto hemicellulose using surface plasmon resonance. Proceeding of The 2nd International Symposium on Technologies of Pulping, Papermaking and Biotechnology on Fiber Plants, 521-524 (2004).
  • “木質系有機資源の新展開”<舩岡正光監修>
    シーエムシー 2004年 [査読無し][通常論文]
  • H Sato, Y Uraki, T Kishimoto, Y Sano CELLULOSE 10 (4) 397 -404 2003年12月 [査読無し][通常論文]
     
    To explore further potential applications of acetic acid pulp, an investigation was conducted to develop a direct method for producing cellulose acetate from wood in combination with atmospheric acetic acid pulping. The process consists of delignification, totally chlorine-free bleaching, and esterification, with the concentrated acetic acid aqueous solution being used as only solvent throughout the process. The acetic acid pulp with kappa number of 30 and ISO brightness of 16 was bleached with 5% ozone on pulp to kappa number of 1.4 and brightness of 61. The resulting bleached pulp was further bleached with peracetic acid to kappa number of less than 1.0 and brightness of 68. The final bleached acetic acid pulp was acetylated with acetic anhydride in the concentrated acetic acid for 45 min to produce cellulose acetate with an apparent degree of substitution (DS) of 2.54. Although the product was lower grade compared with commercially available cellulose diacetate because it was prepared from the chemical pulp but not dissolving pulp, the product was almost soluble in acetone. Eventually, the DS of the acetone-soluble fraction was 2.62. The acetone solubility might be attributed to the original acetic acid pulp that had been partially acetylated during the pulping.
  • 井村健, 浦木康光, 岸本崇生, 生方信 日本木材学会北海道支部講演集 (35) 74 -77 2003年10月15日 [査読無し][通常論文]
  • 高森ひとみ, 岸本崇生, 浦木康光, 生方信 リグニン討論会講演集 48th 176 -177 2003年10月15日 [査読無し][通常論文]
  • 井村健, 浦木康光, 岸本崇生, 生方信 リグニン討論会講演集 48th 200 -201 2003年10月15日 [査読無し][通常論文]
  • 高森ひとみ, 岸本崇生, 浦木康光, 生方信 日本木材学会北海道支部講演集 (35) 78 -81 2003年10月15日 [査読無し][通常論文]
  • 根本純司, 浦木康光, 岸本崇生, 生方信, 田中賢, 下村政嗣 日本木材学会北海道支部講演集 (35) 25 -28 2003年10月15日 [査読無し][通常論文]
  • 臼倉ゆり子, 浦木康光, 岸本崇生, 生方信, 平沖敏文, 福島和彦 リグニン討論会講演集 48th 202 -205 2003年10月15日 [査読無し][通常論文]
  • 岸本崇生, 浦木康光, 生方信 リグニン討論会講演集 48th 68 -71 2003年10月15日 [査読無し][通常論文]
  • 臼倉ゆり子, 浦木康光, 岸本崇生, 生方信, 加藤俊之, 福島和彦 日本木材学会北海道支部講演集 (35) 70 -73 2003年10月15日 [査読無し][通常論文]
  • 植木飛鳥, 斉藤香織, 福島和彦, 岸本崇生, 浦木康光, 生方信 リグニン討論会講演集 48th 178 -179 2003年10月15日 [査読無し][通常論文]
  • T. Kishimoto, H. Tsuji, Y. Uraki and Y. Sano: Ozone bleaching of atmospheric acetic acid pulp from Betula platyphylla var. japonica Hara. Holzforschung, 57, 181-188 (2003).*
    2003年 [査読無し][通常論文]
  • Y. Usukura, Y. Uraki, T. Kishimoto and Y. Sano: Characterization of amphiphilic lignin derivative-Formation of Langmuir Blodgett film and Gel. Proceedings of 12th International Symposium on Wood and Pulping Chemistry, vol.1, 329-332 (2003).
    2003年 [査読無し][通常論文]
  • J. Nemoto, Y. Uraki and Y. Sano:Preparation of fiberboards from waste papers and isolated lignins. Proceedings of 12th International Symposium on Wood and Pulping Chemistry, vol.1, 219-222 (2003).
    2003年 [査読無し][通常論文]
  • リグニン-古紙複合物を原料とするボード状成形物の作製とその特性
    木材学会誌 49 287 -292 2003年 [査読無し][通常論文]
  • S Kubo, Y Uraki, Y Sano JOURNAL OF WOOD SCIENCE 49 (2) 188 -192 2003年 [査読無し][通常論文]
     
    Catalytic graphitization of hardwood acetic acid lignin (HAL) with nickel (II) acetate was investigated regarding the production of highly crystalline carbon. Fusibility, one of the unique characteristics of HAL, was preserved with nickel acetate additions up to 0.3% (as the weight of nickel), although the thermal mobility of HAL was depressed by the addition of nickel acetate. An obvious effect of nickel salt as a catalyst on the development of carbon crystallite from HAL was observed for more than 0.2% addition. The development was found to proceed above 850degreesC. All the resulting carbons had turbostratic structure, and the apparent crystallite size (L-c) was increased with increasing amounts of catalyst, as determined by X-ray diffraction. Thus, highly crystalline carbon was produced from HAL by catalytic graphitization without compromising the fusibility of HAL by adding a small amount of organic nickel salt.
  • M. Nishida, Y. Uraki and Y. Sano: Lignin gel with unique swelling property. Bioresource Tech., 88, 81 – 83 (2003).*
    2003年 [査読無し][通常論文]
  • M. Mustafaev, Z. Mustafaeva, E. Ergen, Y. Uraki, Y. Sano: Novel betulin-containing polyelectrolyte conjugates. Journal of Bioactive and Compatible Polymers, 17(4), 251-269 (2002).*
    2002年 [査読無し][通常論文]
  • Y. Miharu, Y. Uraki, K. Itoyama, F. Miyazawa, Hi. Tanibe and Y. Sano: Improvement of moisture sorption of polyurethane fiber by blending cellulose. Sen-i Gakkaishi, 58, 375-380 (2002).*
    2002年 [査読無し][通常論文]
  • Y Uraki, S Kubo, Y Sano JOURNAL OF WOOD SCIENCE 48 (6) 521 -526 2002年 [査読無し][通常論文]
     
    To expand the utilization of waste newspapers and lignin, activated carbon (AC) sheets, as an example of AC moldings, were prepared from those mixtures. The isolated lignins used were softwood and hardwood acetic acid lignins (SAL and HAL), softwood kraft lignin (KL), and wheat-straw lignin (WSL). The mixtures were molded into precursory sheets by thermal compression and then converted to AC sheets by carbonization and steam activation. The flexural strength of the precursory sheets was dramatically improved by additing the lignins compared to that of sheets without lignin. The strength of several sheets was more than 25MPa. This suggested that lignins act as adhesives. SAL and HAL sheets with 40% newspaper were strengthened by the carbonization, whereas the strength of other lignin sheets was depressed. Finally, the AL-based AC sheets showed higher flexural strength (>6MPa) than others. Most of the AC sheets had adsorption ability comparable to that of commercially available AC powder and granules. The capacities were almost independent of paper content. Among the AC moldings tested, the AL-based AC sheets showed the fastest adsorption to p-chlorophenol. Thus, viable AC moldings can be prepared from lignin-wastepaper mixtures, particularly SAL and HAL.
  • Y Uraki, M Morito, T Kishimoto, Y Sano HOLZFORSCHUNG 56 (4) 341 -347 2002年 [査読無し][通常論文]
     
    The water-soluble fraction (WS) from waste liquor of atmospheric acetic acid pulping was analyzed in order to explore its potential utilization as a carbon source for bacterial cellulose (BC) production. The unpurified WS that contained colored compounds had appreciable antibacterial activity and was therefore not used as a carbon source for BC production with the bacteria Acetobacter xylinum ATCC 10245 and 53582. However, the bacteria produced BC from purified WS of both fir and birch after activated carbon treatment, The yields of BC were much lower compared to those using glucose as a typical carbon source in the Hestrin-Schramm (HS) medium. In order to improve the cellulose production, monosaccharides derived from hemicellulose sugars in WS were modified. The WS from softwood was reduced by catalytic reduction, i.e. mannose, the major component of softwood monosaccharides derived from hemicelluloses, was converted to mannitol. In the case of hardwood WS, xylose was isomerized with glucose isomerase to xylulose. The yield of BC was considerably enhanced by both modifications of the WS. The yield of BC using the modified WS from the pulping of fir was superior to that using glucose as carbon source.
  • S. Kubo, Y. Uraki and Y. Sano: "Catalytic graphitization of hardwood acetic acid lignin with nickel (II) acetate.", Proceedings of11th Internatiuonal Symposium on Wood and Pulping Chemistry, vol. 2, 115-118 (2001).
    2001年 [査読無し][通常論文]
  • Y Uraki, A Nakatani, S Kubo, Y Sano JOURNAL OF WOOD SCIENCE 47 (6) 465 -469 2001年 [査読無し][通常論文]
     
    Softwood acetic acid lignin (SAL) free from a high-molecular-mass fraction could be spun at 220degreesC by a spinning machine equipped with an extruder. Although the resulting fibers required thermostabilization, this step could be conducted with a faster heating rate than that for fibers obtained from hardwood acetic acid lignin (HAL). The thermostabilized SAL fibers were converted to activated carbon fibers (ACF) by carbonization in a stream of nitrogen at 1000degreesC, followed by steam activation at 900degreesC. At an activation time of 40 min, the SAL-ACF had a larger specific surface area than the corresponding HAL-ACF. When the activation time for SAL carbon fibers was prolonged to 80 min, the adsorption capacities of resulting ACF against iodine and methylene blue were markedly increased, as was the surface area of the ACE It was found that SAL-ACF had adsorption properties comparable to those of high-performance commercial ACE Also, it had a tensile strength equal to that of a pitch-derived ACF.
  • Y. Uraki, M. Morito, T. Kishimoto and Y. Sano: "Conversion of hemicellulose sugar to carbon resources for bacterial cellulose production.", Proceedings of 11th Internatiuonal Symposium on Wood and Pulping Chemistry, vol. 2, 111-114 (2001).
    2001年 [査読無し][通常論文]
  • Y Uraki, N Ishikawa, M Nishida, Y Sano JOURNAL OF WOOD SCIENCE 47 (4) 301 -307 2001年 [査読無し][通常論文]
     
    A polymeric amphiphile. PE-AL, was prepared from acetic acid lignin (AL) obtained by acetic acid pulping of birch under atmospheric pressure with polyethylene glycol diglycidyl ether (PE) as the crosslinker. The behavior of PE-AL solutions and the complex formation of PE-AL with protein were investigated to clarify the function of this novel lignin derivative. The reduced viscosity of the amphiphile in aqueous solution was low (<0.3 dl/g), and it decreased with increasing concentration in dilute solution. This suggested that the PE-AL in aqueous solution has a structure similar to that of Einstein's sphere and shrinks upon hydrophobic interaction among the structural moieties in AL and the exclusive volume effect. The amphiphilic PE-AL obviously formed a complex with bovine serum albumin (BSA) at 4<degrees>C with a reaction time of about 1 week. After complex formation with cellulase for 1 week, the cellulase activity of the resulting complex is significantly enhanced and is preserved after recycling the complex for hydrolysis of cellulosic materials several times.
  • M. Nishida, Y. Uraki and Y. Sano: "Preparation of lignin based hydrogel and its interaction with amphiphilic compounds.", Proceedings of11th Internatiuonal Symposium on Wood and Pulping Chemistry, vol. 2, 43-46 (2001).
    2001年 [査読無し][通常論文]
  • S Shimamoto, Y Uraki, Y Sano CELLULOSE 7 (4) 347 -358 2000年12月 [査読無し][通常論文]
     
    The structure and properties of a chiral nematic phase, which reflects one hand of circularly polarized light in a narrow region of wavelength, of fully acetylated (ethyl) cellulose [(acetyl) (ethyl) cellulose, AEC] in acrylic acid (AA) were studied in comparison with (ethyl) cellulose (EC). AEC mesophase formed right-handed chiral nematic structure while EC formed left-handed one. AEC mesophase showed higher birefringence and reflection intensity. The relationship between the reflection wavelength and the polymer concentration was negatively correlated for both AEC and EC mesophases. The relationship between the reflection wavelength and the molecular weight was also negative for AEC mesophase whereas positive for EC mesophase. AEC mesophase was solidified by photopolymerization of AA moiety. It was revealed that the optical properties of AEC mesophase could be preserved by photopolymerization, since the resulting solid material reflects selectively one hand of circularly polarized light.
  • Y Uraki, R Taniwatashi, S Kubo, Y Sano JOURNAL OF WOOD SCIENCE 46 (1) 52 -58 2000年 [査読無し][通常論文]
     
    As an example of activated carbon (AC) moldings, AC sheets were prepared from thermoplastic acetic acid lignin by lamination. The resulting AC sheets are a new type of product that can be applied as water and air cleaners. Powdered softwood acetic acid lignin (SAL) was molded into sheets by a thermal pressing method. When the sheet was carbonized under a stream of nitrogen at 1000 degrees C, it was deformed with expansion and contained much foam. The deformation during carbonization was suppressed by the addition of pulp to the lignin. A sheet prepared by mixing lignin with pulp was directly carbonized without thermostabilization. The carbonized sheet was activated with steam for 2 h. The resulting AC sheet had adsorption properties, such as specific surface and iodine adsorption capacity, comparable to those of commercial AC powders or granules. Furthermore; the AC sheet had a larger capacity to adsorb methane than did the commercial AC powder. Therefore, SAL seems to be a promising source for the AC moldings.
  • Y Uraki, A Hanzaki, K Hashida, Y Sano HOLZFORSCHUNG 54 (5) 535 -540 2000年 [査読無し][通常論文]
     
    Acetic acid pulps (AAPs) have been converted to amphiphiles by hydroxypropylation. The resulting hydroxypropyl derivatives (HP-AAPs) formed self-aggregates in water. The interaction of HP-AAP molecules was investigated by a viscometric method. The reduced viscosity (eta(sp)/c) of HPA-AP in both water and chloroform was increased remarkably above a concentration of 0.1% This implies that HP-AAP molecules strongly interact with each other, caused by the hydrophobic interaction of residual lignins in water and by hydrogen bonding of polysaccharides in chloroform. The self-aggregates adsorb water-soluble fluorescent agents. The highest adsorption capacity was observed at the lowest pH among three pH conditions investigated. They also solubilized sparingly water-soluble fluorescent agents in water in larger amounts than did sodium dodecyl sulfate when used as a surfactant. These results suggest that the self-aggregates of HP-AAP adsorb low molecular mass compounds as inclusion compounds. To clarify the interaction of HP-AAP with biopolymers as high molecular mass compounds, the change in the activity of papain, a protease, in phosphate buffer (pH 6.2) was examined in the presence and absence of HP-AAP. HP-AAP acted as an inhibitor of papain at the initial stage of mixing. After mixing for 24 hours, however, the papain activity was revived and preserved for 6 days. In contrast, the papain activity vanished in the absence of HP-AAP after 24 hours because of autolysis. Therefore, HP-AAP protects papain against autolysis, resulting from tight complexation with the biopolymer.
  • 梶本 純子, 佐野 嘉拓, ウイドド ワヒュエコ, 岸本 崇生, 浦木 康光 紙パ技協誌 54 (9) 1252 -1259 2000年 [査読無し][通常論文]
     
    バイオマス総合利用が可能で, 無公害, 省資源, 省エネルギー型新規パルプ製造法を開発するために, 高沸点有機溶媒 (HBS) を用いたHBSパルプ化法を検討した。
    有機溶媒パルプ化法では, 一般に針葉樹のパルプ化は難しいと報告されている。もし, 針葉樹のパルプ化が可能であれば, 広葉樹, 農業廃棄物, 草本類などのバイオマスも容易にパルプ化されると考え, 先ず, 針葉樹 (トドマツ) のHBSパルプ化を行った。HBSとして, 比較的安定と考えられる1, 4-ブタンジオール (1, 3-BDOL), 1, 3-プタンジオ-ル (1, 3-BDOL) などを使用した。HBSパルプ化を溶媒の種類と水の比率, パルプ化の温度 (200-220℃) と時間 (1-2時間), 酢酸触媒の添加量 (溶媒の0-10%) を変えて検討した。用いた溶媒の間にはパルプ化に大きな差異はなかった。
    トドマツは5%酢酸, 70%HBS, 220℃, 2時間のパルプ化条件により脱リグニンの進んだパルプが50%前後で得られた。エゾマツ, 杉, カラマツについても, トドマツの条件でパルプ化を行った。許容できる範囲でこれらの針葉樹もHBSパルプ化された。HBSに酢酸を加えて, パルプ化温度に加熱すると, 溶媒の一部が分解する結果が得られた。パルプ残存リグニンが若干多いが, 酢酸無添加でもパルプ化できる結果が得られていること, また, HBS溶媒系の簡素化も計れることから, 酢酸無添加の条件で更にHBSパルプ化を検討した。
  • Y. Uraki, Y. Miharu, R. Funada, Y. Sano, M. Mitsuhashi, K. Itoyama and H. Tanibe: "Preparation and Characterization of Alginate-blended Rayon"., Sen-i Gakkaishi, 56, 482-486(2000).*
    2000年 [査読無し][通常論文]
  • 『ウッドケミカルスの最新技術』<飯塚尭介, 監修>
    シーエムシー 2000年 [査読無し][通常論文]
  • Y Uraki, Y Sano HOLZFORSCHUNG 53 (4) 411 -415 1999年 [査読無し][通常論文]
     
    Polyhydric alcohol pulping was developed to separate components of low-quality softwoods that are produced by thinning and improvement cutting as well as to establish a self-supporting pulping system. Propylene glycol (PG) was superior to ethylene glycol (EG) as solvent for polyhydric alcohol pulping at atmospheric pressure. PG pulping of fir, larch and cedar, with sulfuric acid as a catalyst, gave satisfactory pulps with few rejects and a very low level of residual lignin as compared with EG pulping. The PG pulps were readily bleached to approximately Kappa number 1 and 80% brightness by one treatment with sodium chlorite. The yield of bleached pulp from fir was 44.7% based on chips. The bleached pulps had very high ex-cellulose content and crystallinity, and their mechanical properties were similar to those of kraft pulp. Therefore, polyhydric alcohol pulping appears to be promising for pulping of softwoods by an organosolv method.
  • Y. Urakj, N. Ishikawa, M. Nishida and Y. Sano: "Stabilization of cellulase with amphiphilic acetic acid lignin derivative", Proceedings of 10th Internatiuonal Symposium on Wood and Pulping Chemistry, vol. I, 470-473 (1999).
    1999年 [査読無し][通常論文]
  • S. Kubo, Y. Uraki Y. Sano and K.-l. Chen: ”Preparation of functional carbonaceous materials from isolated lignins”, Proceedings of10th Internatiuonal Symposium on Wood and Pulping Chemistry, vol. III, 388-393 (1999).
    1999年 [査読無し][通常論文]
  • 浦木 康光, 佐野 嘉拓, 糸山 光紀, 谷辺 博昭 キチン・キトサン研究 = Chitin and chitosan research 4 (2) 150 -151 1998年05月15日
  • S Kubo, Y Uraki, Y Sano CARBON 36 (7-8) 1119 -1124 1998年 [査読無し][通常論文]
     
    Infusible softwood acetic acid lignin (SAL) was converted to a Fusible one as a raw material for carbon fibers by removing the infusible high molecular mass fraction-The resulting low molecular mass fraction (SAL-L) was spun by fusion spinning after thermal treatment to remove volatile materials. Carbon fibers (CFs) were prepared From these fibers by direct carbonization without thermostabilization, leading to reduction of the production costs. The tensile strength of SAL-L CFs increased with decreasing diameter, and those of the fine SAL-L CFs were comparable to those of other lignin based CFs such as phenolated exploded lignin. Therefore, SAL-L CFs were classified into general performance grade. (C) 1998 Elsevier Science Ltd. All rights reserved.
  • 潘 学軍, 佐野 嘉拓, 中嶋 博, 浦木 康光 紙パ技協誌 52 (3) 408 -415 1998年 [査読無し][通常論文]
     
    In order to make use of rice straw (Oryza sativa L. cv. Kirara 397) as agricultural wastes effectively and to develop a novel pulping method for rice straw without environmental impact, an atmospheric acetic acid pulping was studied. The results indicated that the acetic acid pulping process is a promising method for rice straw. The straw gave screened pulps with satisfactory strength properties when refluxed in 80-90% aqueous AcOH with 0.32% H2SO4 or 0.10% HCl as catalyst for 3 hours. The aqueous AcOH was recovered from the waste liquor and AcOH washings by distillation without troublesome problems, and AcOH lignin and water solubles as sugars were prepared as by-products from the concentrated waste liquor by fractional precipitation with water. The ash contents in screened pulp, fines, water solubles and AcOH lignin were about 18, 24, 18 and 1.5%, respectively. The ash in the pulp and fines consisted mainly of silica which located not in fiber and parenchyma cells but only in epidermal cells as shown by a SEM-EDXA photograph. The silica left in the pulp may function as a filler of paper.
  • Y.-G. Kim, N. Watanabe, Y. Sano, Y. Uraki and Y. Sano:"Extractives of Kitakobushi Magnolia Kobus DC. var. borealis Sarg. III. -Antibacterial and Antifungal Activity of Extractives.-", Research Bulletin of The Hokkaido University Forests, 55, 63-73 (・・・
    1998年 [査読無し][通常論文]
     
    Y.-G. Kim, N. Watanabe, Y. Sano, Y. Uraki and Y. Sano:"Extractives of Kitakobushi Magnolia Kobus DC. var. borealis Sarg. III. -Antibacterial and Antifungal Activity of Extractives.-", Research Bulletin of The Hokkaido University Forests, 55, 63-73 (1998)*
  • Y Uraki, K Hashida, Y Sano HOLZFORSCHUNG 51 (1) 91 -97 1997年 [査読無し][通常論文]
     
    Acetic acid pulp (AAP) containing more than 8 % residual lignin was chemically modified to prepare hydroxypropylated pulps (HP-AAPs) by treatment with propylene oxide under alkaline conditions. HP-AAPs with residual lignin had an amphiphilic properly. After negative staining, transmission electron micrographs indicated that HP-AAP formed self-aggregates in water which were converted into small particles with diameters in the nano meter range by ultrasound sonication. The aggregates were revealed to have strong hydrophobic domains by the fluorometric study of their complexes with fluorescent reagents as indicators for hydrophobicity. However, commercial hydroxypropylated cellulose and carboxymethylated AAP did not form self-aggregates and had little hydrophobic domain. These results suggest that HP-AAP aggregates in water by the hydrophobic interaction of the residual lignin, and the aggregates have a tendency to form complexes with hydrophobic materials. Thus, the amphiphilic derivatives have the same properties as inclusion compounds do.
  • S Kubo, N Ishikawa, Y Uraki, Y Sano MOKUZAI GAKKAISHI 43 (8) 655 -662 1997年 [査読無し][通常論文]
     
    Softwood acetic acid lignin (S-AL), obtained by aqueous acetic acid pulping of todomatsu (Abies sachalinensis Masters), is infusible. In this study, a method for conversion of S-AL to a fusible material for the preparation of lignin fibers was developed based on examination of the relationship between the thermal properties and the chemical structure of S-AL. S-AL was found to be converted to fusible material by removal of the high-molecular-mass fraction by solvent extraction with 70% acetic acid, with a yield of 80%. From a comparison of the chemical structure of the fusible and infusible fractions, we found that the structures of aromatic nuclei in the acetic acid lignin (AL), such as condensed and aryl-ether structures, were related closely to the thermal mobility of AL. The large contents of condensed and aryl-ether structures in AL seemed likely to hinder thermal motion. Therefore, the cutting of aryl-ether bonds by re-cooking with aqueous acetic acid resulted in a fusible lignin, with a yield of approximately 90%. The fusible fraction of S-AL and the re-cooked S-AL were capable of being spun by fusion spinning.
  • Uraki, Y., Chen, C. -L. and Gratzl, J. : "Sonolysis of Chloro-Organics in Bleach Plant E-1 Effluents", Holzforschung, 51 : 452-458 (1997)*
    1997年 [査読無し][通常論文]
  • Uraki, Y., Kubo, S. and Sano, Y. : "Characteristics of Activated Carbon Fibers Prepared from Acetic Acid Lignin", Proceedings ATC '97 The 4th Asian Textile Conference, 1 : 36-41 (1997)
    1997年 [査読無し][通常論文]
  • Uraki, Y., Kubo, S., Kurakami, T., and Sano, Y. : "Activated Carbon Fibers from Acetic Acid Lignin", Holzforschung, 51(2) : 188-192 (1997)*
    1997年 [査読無し][通常論文]
  • S. Kudo, Y. Uraki and Y. Sano : "Thermomechanical Analysis of Isolated Lignins", Holzforschung, 50 : 144-150 (1996)*
    1996年 [査読無し][通常論文]

書籍等出版物

  • 浦木康光 (担当:共著範囲:木材成分セルロースとリグニンのエレクトロスピニング)
    シーエムシー出版 2021年03月 (ISBN: 9784781315928) 9,341p
  • 表面技術
    浦木康光 (担当:共著範囲:蓄電デバイス用セパレータ)
    2020年06月
  • 浦木康光 (担当:共著範囲:リグニンの単離・改質とリグニンを活用した機能性材料の開発)
    シーエムシー出版 2020年03月 (ISBN: 9784781314945) iv, 227p
  • 加工技術
    浦木康光 (担当:共著範囲:リグニンを主原料とするポリエステルフィルムの調製とその利用)
    2018年05月
  • 木質の化学
    文永堂出版 2010年
  • 「機能性リグニン-多糖複合体の開発」
    シーエムシー出版 2007年
  • Development of functional lignin-carbohydrate complex
    CMC Publisher 2007年

所属学協会

  • リグニン学会   木質炭化学会   日本農芸化学会   アメリカ化学会   繊維学会   キチン・キトサン学会   日本木材学会   セルロース学会   高分子学会   The Wood Carbonization Research Society   American Chemical Society   The Society of Fiber Science and Technology, Japan   Japanese Society for Chitin and Chitosan   The Japan Wood Research Society   The Cellulose Society of Japan   The Society of Polymer Science, Japan   

共同研究・競争的資金等の研究課題

  • 日本学術振興会:科学研究費助成事業
    研究期間 : 2021年04月 -2026年03月 
    代表者 : 浦木 康光, 堤 祐司, 玉井 裕, 綿岡 勲, 鈴木 栞, 重冨 顕吾
     
    当該年度は、3つの課題について検討を行い、以下の成果を得た。 1. rCWPO-Cの高純度化と多量発現:組換体大腸菌によるタンパク質の発現と精製工程にいて、TAPS化とリフォールディングの間に遠心分離を2回の行う操作を加えた。この結果、精製rCWPO-Cの収率を維持したまま、ペルオキシダーゼの精製度を示すRZ値が約1.5倍に増加し、比活性も約1.5倍の560μmol/min/mgまで向上した。 2.細胞壁構成多糖類間および多糖類-ペルオキシダーゼ間のの相互作用解析:木材のヘミセルロース(キシラン、グルコマンナン、キシログルカン)とセルロースとの相互作用を、平衡吸着実験と速度論的解析が可能なQCM-Dを用いて行った。両測定とも、キシログルカンがセルロースに最も吸着することが明らかとなった。また、Horseradish peroxidase(HRP)と多糖類との相互作用解析では、HRPはセルロースに対し、高い親和性を示すことも分かった。さらに、多糖類が脱水素重合体(DHP)の形成に及ぼす影響も調べ、キシログルカンがDHPを多量生成させ、加えて、5-5’縮合結合の形成も促進することが示された。この結果より、一次細胞壁が縮合構造に富む理由が解明できた。 3.高分子リグニンの蛍光共鳴エネルギー移動(FRET)の測定:FRET測定の最初の取り組みとして、固体試料を対象とした蛍光顕微鏡でFRETが示されているリグニンと蛍光試薬ローダミンとの相互作用を、溶液中で検出することから検討した。使用したリグニンは広葉樹のクラフトリグニンである。この測定の結果、プロピレングリコールを溶媒とする溶液中で、FRETを観測することができた。モノリグノールとクラフトリグニンとのFRETの検出を試みたが、どちらも蛍光強度が弱かったために、明確なFRET検出には至っていない。
  • 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。
  • 日本学術振興会:科学研究費助成事業
    研究期間 : 2014年06月 -2018年03月 
    代表者 : 浦木 康光, 重冨 顕吾, 玉井 裕, 吉永 新, 岸本 崇生, 高部 圭司, 幸田 圭一
     
    本研究では、リグニン形成(木化)に及ぼす多糖類、特に、ヘミセルロースの影響について解明することを目的とした。木材で代表的なヘミセルロースであるキシランとグルコマンナンをセルロースに吸着させて、多糖類マトリックする作製した。このマトリックス存在下で、リグニンのモノマーであるコニフェリルアルコールの脱水素重合を行った。その結果、キシランは脱水素重合を促進したが、グルコマンナンは阻害するという、従来報告されていない知見を得た。さらに、リグニンモデル高分子の溶液物性と得られた重合物(DHP)の溶液物性を比較することによって、DHPは枝分かれに富む構造を有することが明らかとなった。
  • 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。
  • 日本学術振興会:科学研究費助成事業
    研究期間 : 2007年 -2010年 
    代表者 : 井上 京, 平野 高司, 波多野 隆介, 谷 宏, 斎藤 秀之, 玉井 裕, 大崎 満, 秦 寛, 橋床 泰之, 浦木 康光, 俵谷 圭太郎, 原口 昭, 安部 竜一郎
     
    巨大なカーボン・シンクであり,かつ生物多様性に富みつつも脆弱な生態系である熱帯泥炭地を対象に、カーボンフロー・コントロールに立脚した土地利用・管理の最適化方策を確立することを目的に,泥炭火災の抑止と荒廃した土地の再生をすすめ、熱帯泥炭地における持続的生物生産活動を確立しつつ環境負荷を軽減するための種々の方策について検討した。
  • 日本学術振興会:科学研究費助成事業
    研究期間 : 2006年 -2008年 
    代表者 : 浦木 康光, 平井 卓郎, 玉井 裕, 岸本 崇生, 杉山 淳司, 杉山 淳司
     
    樹木細胞壁の二次壁の特徴は、他の壁組織に比べ多量に存在するリグニンとその化学構造である。本研究では、二次壁模倣材料の創出を目的に、二次壁リグニン模倣高分子を創製して、その物性を明らかにした。さらに、ハニカムパターン化セルロースにリグニンを吸着させて二次壁模倣セルロース材料を創製して、その物性解析からリグニンが高湿度における細胞壁の強度低下を抑制することを見出すと共に、木材成分のみで高強度材料を創出できることを明らかにした。
  • 日本学術振興会:科学研究費助成事業
    研究期間 : 2003年 -2005年 
    代表者 : 浦木 康光, 高部 圭司, 福島 和彦, 近藤 哲男, 船田 良, 玉井 裕
     
    本課題研究では、分子レベルから組織レベルにおいて階層構造を有している樹木細胞壁の構築機構を解明し、この結果を基に、細胞壁の構築過程を人為的に模倣した物質、即ち人工細胞壁を創製することを目的とし、下記の9項目の結果を得た。 第1項目として、細胞壁主要3成分の堆積過程を免疫電子顕微法などにより分子レベルで追跡し、細胞壁形成におけるキシランの重要性を明らかにした。第2項目では、表面プラズモン共鳴に基づく生体分子間相互作用解析装置を用い、第1項目で得られた知見を物理化学的に支持する成果を得た。第3項目として、今まで殆ど解明されていなかったリグニン-炭水化物複合体(LCC)の物性及び期待される機能を解明し、LCCの細胞壁における機能及び機能性材料としての潜在性に明示した。第4項目では、リグニンの構造及び物性解析に寄与する新規な分析法やモデル化合物の調製法を明らかにし、リグニン化学への新たな展開を明示した。第7項目では、細胞レベルにおける壁形成について新たな知見を見出し、さらに、細胞の繋がりによる組織形成の解明へと、樹木細胞壁の階層構1造を段階的に解明した。 第8項目では、第7項目までの知見を基に、ハニカム状に細胞壁が配列している構造を模倣した人工細胞壁の構築技術の開発を行った。先ず、セルロース誘導体からハニカム状物質を作成する技術を開発した。しかし、このハニカム物質は再生セルロースであり、樹木細胞壁のセルロース1とは異なる結晶構造であった。そこで、セルロース1を産生する酢酸菌をセルロース製造マシンとして利用するハニカム状セルロースの調製法を開発した。また、酢酸菌によるセルロース産生の炭素源として、キノコ生産の廃棄物が利用できることを、第9項目の結果として得た。これらのことより、人工細胞壁を構築する基礎技術は、本研課題研究において創出できたと云える。
  • 人工細胞壁の創製
    科学研究費補助金
    研究期間 : 2002年
  • Creation of artificial cell wall
    Grant-in-Aid for Scientific Research
    研究期間 : 2002年
  • 日本学術振興会:科学研究費助成事業
    研究期間 : 1999年 -2001年 
    代表者 : 佐野 嘉拓, 田畑 昌祥, 浦木 康光, 篠原 邦夫, 岸本 崇生, 久保 智史
     
    シラカンバは寒冷地に大量に存在する早生広葉樹であるが、有効利用されずに放置されている。北海道には他にも、多くの除・間伐材、わら類などの農業廃棄物が存在する。これら未利用資源を有効利用できるバイオマス変換産業を北海道に創出するための基礎的・応用的研究を行った。更に、シラカンバ外樹皮に特異的に存在するベチュリンを生分解性ポリマー、界面活性剤、生理活性物質など高度な用途に利用する技術の確立を計った。 シラカンバ木材、農業廃棄物などをバイオマス変換産業の原料に利用するために、主要成分であるセルロース、リグニンとヘミセルロースの無公害・省エネルギー・省資源型簡易成分分離技術(常圧酢酸法とHBS成分分離法)を新たに開発した。50%を占めるセルロースは製紙、糖化・発酵によるバイオケミカルス、機能性セルロース誘導体など広範な用途に利用できることを明らかにした。ヘミセルロースとリグニンもほぼ定量的に単離され、ヘミセルロースはバイオケミカルス、食料添加物、医薬品、リグニンはクリーンで高熱量の燃料シックレス接着剤、環境浄化資材など高度な用途に使用できた。ベチュリンを簡易に単離・精製し、生分解性プラスチック、医薬品、天然界面活性剤などに利用する技術を確立した。これらの結果は北海道にベチュリン(シラカンバ外樹皮成分)、低質木材、農業廃棄物を有効利用したバイオマス変換産業を創設できることを示唆した。
  • 日本学術振興会:科学研究費助成事業
    研究期間 : 1998年 -2000年 
    代表者 : 佐野 嘉拓, 岸本 崇生, 浦木 康光
     
    現行のクラフトパルプ製造法は薬品回収炉や環境保全設備などの附属設備費が嵩み、採算稼働規模はパルプ千トン/日と報告されている。また、クラフト法ではパルプ以外の成分はパルプ化薬品の回収のために燃焼しなければならないために、バイオケミカルスなどの有用な用途には利用できない。 パルプ製造に要するエネルギーを削減し、廉価で環境に温和な多用なエネルギー源を利用することにより、パルプ以外の膨大な量の貴重なバイオマス成分は有用な用途に高度利用できる。また、薬品回収炉や環境保全設備などの設備を必要としない小規模でも稼働可能なパルプ製造法が確立できれば、除間伐材、農産廃棄物、繊維植物などの分散型繊維原料もパルプ原料として広範に使用し、森林資源の乱伐による環境破壊を回避することができる。 そのような観点から、自己完結型有機溶媒を用いた省資源、無公害パルプ製造法を検討した。木材などのバイオマスの炭水化物から糖化・発酵で調製可能なプロピレングリコール(PG)を主要な多価アルコール有機溶媒(PHA)に用いることにより、省エネルギー・無公害型で小規模な装置で稼働できるパルプ製造法が確立された。特に、PHAパルプ廃液からリグニンのみを水で沈殿回収し、調製した回収廃液(RPG)は優れたパルプ化溶媒としての特性を備えていることが明らかになった。その結果、RPGから蒸留でPGを精製するエネルギーが必要としないことから、RPGをパルプ化溶媒とする省エネルギーの進んだパルプ製造法とすることが可能であることが明らかになった。このプロセスで得られるリグニンは特異な熱溶融性を示し、また、フェノール性水酸基が多い可溶性リグニンであることから、リグニン炭素繊維、リグニン成形活性炭、エポキシ樹脂などの広範な用途に利用できることが明らかになった。研究は更に発展させ、PG以外の熱安定性の高い高沸点アルコール溶媒(HBS)をパルプ化溶媒に使用するHBSパルプ製造法の開発が検討されている。
  • 日本学術振興会:科学研究費助成事業
    研究期間 : 1998年 -1999年 
    代表者 : 浦木 康光
     
    リグニンを含むパルプをリグノセルロースと見なし、ヒドロキシプロピル化により、水及び有機溶媒に可溶な両親媒性誘導体を調製した。本年度は、両親媒性誘導体と生体高分子との相互作用による生体高分子の構造変化について検討した。さらに、相互作用を解明する基礎研究として、この誘導体の水溶液中の構造及び温度変化による形態変化についても検討を加え、この誘導体の基本的物性と利用法について考察した。 牛血清アルブミン(BSA)を生体高分子として用い、誘導体との相互作用による形態変化を円二色性スペクトルにより調べた。BSAはリン酸緩衝液中で48時間2次構造変化は起こさなかったが、96時間以降α-helix構造に由来するコットン効果が減少して変性することが示された。一方、誘導体が存在してもBSAのスペクトルは変化せず、122時間後でも構造が保たれていることが分かった。このことは、誘導体が生体高分子を取り込むような相互作用をしていることを示唆しているが、その作用は生体高分子の構造を変化させるほど強くなく、単に運動性を抑制して変性を妨げていることを意味していると思われる。 物質の取り込み現象を明らかにするために、先ず、誘導体の溶液構造を検討した。X線小角散乱から、この誘導体分子はかなり剛直な棒状高分子であることが示された。光散乱より、誘導体の会合物は球状の構造をしており、これらの結果、残存リグニンが棒状高分子を結びつけ巨大な球状構造を形成していることが明らかになった。また、誘導体は残存リグニン量が多くなると下限共溶臨界温度が低下して、体温付近で沈殿現象を生じることが示され、球状構造の空隙に取り込んだ物質を温度上昇で放出する温度感応性物質として利用できることが分かった。
  • 日本学術振興会:科学研究費助成事業
    研究期間 : 1994年 -1996年 
    代表者 : 佐野 嘉拓, 高井 光男, 小澤 修二, 浦木 康光
     
    間伐木、風倒木、早生広葉樹などの低質材を付加価値の高い用途に利用するために、低質材に含まれる主要な成分を温和な常圧有機溶媒抽出法により成分分離し、各成分の性状と利用法を検討した。カバ、ポプラなどの広葉樹材およびトドマツとエゾマツの針葉樹間伐材は少量の硫酸などを含む酢酸水溶液(AcOH)で煮沸抽出する簡便なAcOHプロセスにより、製紙用パルプ、ヘミセルロースおよびリグニンにほぼ定量的に分別分離することが可能であった。スギとカラマツの各間伐材も同様に成分分離されたが、パルプ中に残存リグニンが多く存在した。新たな多価アルコール系溶媒を用いたPHAプロセスにより、これらの低質材の成分分離を検討した。PHAプロセスではスギやカラマツも支障なくパルプ化され、リグニンを大量に回収することが可能であった。PHA系の溶媒は酢酸と同様に、パルプ化により消費された部分をパルプ副産物の多糖類から製造し、補給することが可能である。成分分離した各成分の性状と利用法を検討した。AcOHとPHAの両プロセスから得たパルプは何れも、製紙用パルプとしての特性を有し、特に後者のパルプは残存リグニンが少なく、漂白が容易であり、グルコース含量が高いことから、溶解用パルプにも利用出来る。AcOHリグニン、特にAcOH広葉樹リグニンは特異的な熱溶融性を示し、溶融紡糸-不融不溶化-炭素化による簡便で経済的な方法により炭素繊維に変換することが出来た。また、廉価な炭素繊維を原料として高価な繊維状活性炭を製造することも可能であり、パルプ副産物のリグニンの汎用的な有効利用法を確立された。糖類は発酵原料、ケミカルス原料や食品添加物に利用できる。 以上の結果、省エネルギー、無公害な新たなAcOHまたはPHAパルプ化法により低質材をパルプ化し、パルプおよび非繊維成分を付加価値の高い用途に高度利用するバイオマス変換プロセスが「低質材の利用法」が有効と考えられる。
  • 日本学術振興会:科学研究費助成事業
    研究期間 : 1994年 -1995年 
    代表者 : 佐野 嘉拓, 深澤 和三, 小島 康夫, 浦木 康光, 佐野 雄三, 船田 良, 大谷 諄, 三浦 清, 佐野 嘉拓
     
    樹木の仮道管や木繊維などには二次壁が形成されるが、細胞壁を構成するセルロース・ミクロフィブリル(MF)の配向変化を立体表現化するには、MFの堆積過程を直接観察により順次追跡する必要がある。そこで、電界放射型走査電子顕微鏡(FE-SEM)によるMFの観察法を確立し、樹木細胞壁における配向変化を観察した。二次壁形成中のMF配向は、二次壁外層から中層まで、内こう側からみて時計回り方向に連続的に変化した。その後、連続的な配向変化は停止し、同じ配向をもつMFが堆積し続け、厚い二次壁中層を形成した。その後、MFの配向は内こう側からみて反時計回り方向に変化し、二次壁内層を堆積した後、MFの堆積は終了した。その結果、二次壁外層では緩傾斜のSへリックスのMFが、二次壁中層では急傾斜のZへリックスのMFが、二次壁内層では緩傾斜のSへリックスのMFが各々堆積し、各層の間の移行層ではらせん構造をもつMFが堆積した。これらの結果を基に、仮道管や木線維における二次壁細胞壁のMF配向をモデル化した。 細胞骨格の一種である表層微小管の配向変化を、分化中仮道管において連続的に追跡した。そこで、研究設備として共焦点レーザ走査顕微鏡を導入し、その操作法を確立した。分化中仮道管において、表層微小管は連続的な配向変化を示し、この配向変化のパターンは、上に述べたMFの配向変化とよく一致しており、表層微小管がMFの配向を制御することを強く示唆した。また、道管、木繊維、放射組織中の表層微小管の立体配置像も三次元構築ユニットを用いて構築し、表層微小管が細胞内においてらせん状に存在することを明らかにした。 以上の研究成果を基に、樹木細胞壁の構築過程を三次元的に表現化した。
  • 日本学術振興会:科学研究費助成事業
    研究期間 : 1993年 -1993年 
    代表者 : 浦木 康光
     
    1.緒言 本研究の目的は、硫酸触媒による常圧酢酸パルプ化法によって得られるリグニン(AWL)から液晶を生成する物質を調整し、最終的に液晶紡糸を行うことであった。液晶物質の調整法として2法考えられ、1つはアルキル鎖の導入やメソ-ゲンとなる官能基導入などのAWLの化学修飾による改質である。もう1つは、高機能の炭素繊維を調整するためピッチ系原料で用いられている加熱によるメソフェーズいわゆる液晶の調整である。2番目の方法は、不均一構造の物質を熱分解と同時に、熱縮合を生じさせて、できるだけ均一構造の会合体を作り液晶を発現させるもので、不均一構造を有するリグニンの液晶化には、簡便で好適な方法と思われた。そこで、この研究では、加熱条件を変えての液晶生成を検討し、走査型電子顕微鏡(SEM)、偏光顕微鏡や熱分析により液晶生成を評価した。 2.実験 (1)AWLの液晶化:AWLを空気中の開放系及びミクロオートクレーブを用いた窒素雰囲気下で昇温速度3℃/minで160℃から430℃まで加熱し、所定温度を40minまたは90min維持した。熱処理AWLのキノリン不溶部を液晶画分としてろ過で回収し、エタノールで洗浄後減圧乾燥した。(2)顕微鏡観察:キノリン不溶部をSEM及び偏光顕微鏡により観察した。 3.結果 AWLを430℃で90min加熱した試料は、SEMでメソフェーズと思われる小球体の形成が観察された。さらに、偏光顕微鏡観察から超薄片部分にクロスニコル下での発光が観察され、液晶の生成を示唆する結果が得られた。また、160℃や250℃でもSEMよりピッチ系メソフェーズでも観察されるサンゴ状組織が見られたが、偏光観察からは液晶の形成は観察されなかった。高温処理試料は、示差走査熱量分析から液晶の熱相転移に起因すると考えられる吸熱ピークが観測され、リグニン液晶がサーモトロピック液晶に近い熱挙動を示すことが示唆された。現在、この液晶の構造を電子線解析により調べると共に、紡糸条件について検討している。
  • 日本学術振興会:科学研究費助成事業
    研究期間 : 1991年 -1992年 
    代表者 : 高井 光男, 杉山 貞夫, 藤原 政司, 清水 祐一, 浦木 康光, 戸倉 清一
     
    イカ背骨中の灰分量は蟹及びエビ類の30〜45%に比較して0.5%と極端に低く、脱灰の手間が省け4%アルカリによる脱蛋白で容易に精製キチンがえられる。精製イカキチン2〜6g(乾燥重量)を水50ml中ホモジナイザー又は、ミキサーで離解し(フリーネス0)、これを水3000ml中へ注ぐ。この懸濁液約200mlずつを吸引式バッチ型抄紙装置でシートを作成した。シート厚さは初期キチン濃度により調整した。抄紙したイカ及びカニキチン紙の走査型電子顕微鏡観察結果によると、カニキチンはミクロフィブリル構造が顕著に発達しているのに対し、イカキチンはフィブリル構造は明確でなくラメラ状構造を示している。振動リード法で求めた動的ヤング率はイカキチン紙で9〜11GPa,カニキチン紙の5GPaよりやや大きい。しかし、このヤング率より求めた曲げかたさでは、イカキチン紙の方がカニキチン紙より1オーダー小さく軟らかい。又、裂断長はイカの6〜7Kmに対してカニは3Kmと小さく、破裂強度についてもカニの1.0に対してイカは5〜7と大きくイカキチン紙は軟らかい。耐折強さも1Kg荷重で15回以上を示した。更にイカキチン紙は水蒸気透過性、吸水率ともカニキチン紙より高く代用皮膚として適している。この他生体人工心臓弁基準による急性毒性試験、発熱性物質試験、溶血性試験、皮内反応試験、移植試験、抗原性試験、抗菌性試験等に於てイカキチン紙は生体適合性の高さを示した。一方、ヒト線維芽細胞による接着率と増殖率を検討したところいずれも市販のベスキチンや組織培養用のコラーゲン膜より高い値を示した。紙・パルプ工場に於ける新聞紙用連続抄紙機に改良を加えたベンチスケールのイカキチン紙用連続抄紙機に試作を行った。その結果イカキチン濃度1-3g/1の懸濁液で0.5m/minの速度で連続20mの抄紙がバインダーなしで可能であり、巻取りボビンでキチン紙平均湿度が40%以下で連続抄紙ができた。本抄紙機はカニキチン紙製造工程よりも簡単で製造コストも安価なイカキチン紙製造が可能である。更に、バインダーや残留有機溶媒の問題が無く安全性も高い。
  • 日本学術振興会:科学研究費助成事業
    研究期間 : 1991年 -1991年 
    代表者 : 浦木 康光
  • 日本学術振興会:科学研究費助成事業
    研究期間 : 1989年 -1991年 
    代表者 : 佐野 嘉拓, 浦木 康光, 笹谷 宜志, 小澤 修二
     
    近代社会の持続的繁栄のためには化石有機資源である石油資源の永続的供給が不可欠であり、節度ある石油資源の消費と共に石油延命・代替資源の開発が必要である。エネルギ-代替資源は原子力・太陽熱・地熱の水力・石炭など数多く提案されているが、ケミカルスの代替資源は石炭・バイオマスくらいしかない。バイオマスは再生可能な資源であり、比較的簡単な処理でペテロケミカルスの95%を代替・製造することが可能であるから重要な石油延命・代替資源である。特に食糧との競合がなく、資源の蓄積量も多い木質バイオマスは有効な代替資源である。また木質バイオマスは長期間にわたり炭酸ガスを固定化し、地球環境の浄化・保全機能が高いから地球規模で撫育していく必要性が叫ばれている。従って環境と資源を調和した森林・木質バイオマスの管理・利用が近代社会の持続的繁栄のための重要な課題である。 木質バイオマスをケミカルス原料に使用する場合、緊密に入り込んで存在する全成分の95%強を占めるセルロ-ス、ヘミセルロ-スとリグニンを出来るだけ変質の少ない化学処理でほぐして各成分に分け、各成分を高度な用途に利用することが必要であるが、現在そのような木質バイオマスの分離法は存在しない。そこで、本研究は環境・資源の両面で重要な広葉樹材を対象に、硫酸を触媒としたフラスコ(常圧)内での分離法を検討した。即ちチップを0.2〜0.4%の硫酸を含む90%酢酸水溶液で煮沸することで不溶性のセルロ-ス(パルプ)と可溶性のホミセルロ-スとリグニンに分離した。セルロ-スは紙・パルプやケミカルスの原料に使用するために基礎的性質を調べ、残存リグニンが若干多く、相当するクラフトパルプに比べて強度持性が劣るが、多くの用途のケミカルパルプや酵素分解してケミカルス原料に利用できることが明らかになった。可溶性物質は水による分別沈殿法でヘミセルロ-ス(水可溶部)とリグニン(水不溶部)に簡単に分けられる。ヘミセルロ-スは大部分がキシロ-スであり、簡単な精製操作で甘味料や医薬品となるキシロ-スを回収できることが明らかになった。また、リグニンの詳細な化学構造の分析を行ったが、リグニンは反応活性なベンジル水酸基が残存し、重量分子量が3,000〜7,000の有機溶媒に可溶性のリグニンであり、20%のフェノ-ルと混合し、リグニン接着剤に使用することが可能であった。リグニンの利用法の開発研究はなお継続している。
  • 木質バイオマスのバイオリファイナリーと分離成分の有効利用,
    科学研究費補助金
    研究期間 : 1989年
  • Biorefinery of woody biomass and effective utilization of refined components
    Grant-in-Aid for Scientific Research
    研究期間 : 1989年


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