2022年, 第45回生物工学奨励賞（照井賞）　　　　　　　　　　　　　　　
有機–無機界面に着目した複合バイオ材料の創製に関する生物化学工学的研究

2012年, 平成23年度化学工学会研究奨励賞（實吉雅郎記念賞）　　　　　　　　　　　　　　　
日本国

2009年, Best Presentation Award, APBioChEC'09　　　　　　　　　　　　　　　
日本国

2006年, Best Ph.D student oral presentation, YABEC 2006 Symposium　　　　　　　　　　　　　　　

2005年, 第12回日本生物工学会九州支部佐賀大会 学生賞（博士の部）　　　　　　　　　　　　　　　
日本国

Feasibility study of enhancing enzyme-induced carbonate precipitation with eggshell waste for sand solidification
Zhen Yan, Kazunori Nakashima, Chikara Takano, Satoru Kawasaki
Biogeotechnics, 2, 4, 100108, 100108, Elsevier BV, 2024年12月
研究論文（学術雑誌）

Utilisation of acid-tolerant bacteria for base metal recovery under strongly acidic conditions
Chikara Takano, Kazunori Nakashima, Satoru Kawasaki, Hideki Aoyagi
Extremophiles, 28, 3, Springer Science and Business Media LLC, 2024年09月24日
研究論文（学術雑誌）

Effect of humic acid on soil solidification by enzyme induced carbonate precipitation
Meiqi Chen, Aoi Ichinohe, Kazunori Nakashima, Chikara Takano, Sivakumar Gowthaman, Lutfian R. Daryono, Satoru Kawasaki
Biogeotechnics, 100133, 100133, Elsevier BV, 2024年08月
研究論文（学術雑誌）

Ecofriendly solidification of sand using microbially induced calcium phosphate precipitation
Maksym Avramenko, Kazunori Nakashima, Chikara Takano, Satoru Kawasaki
Scientific Reports, 14, 1, Springer Science and Business Media LLC, 2024年05月30日
研究論文（学術雑誌）, Abstract

This study introduces microbiologically induced calcium phosphate precipitation (MICPP) as a novel and environmentally sustainable method of soil stabilization. Using Limosilactobacillus sp., especially NBRC 14511 and fish bone solution (FBS) extracted from Tuna fish bones, the study was aimed at testing the feasibility of calcium phosphate compounds (CPCs) deposition and sand stabilization. Dynamic changes in pH and calcium ion (Ca²⁺) concentration during the precipitation experiments affected the precipitation and sequential conversion of dicalcium phosphate dihydrate (DCPD) to hydroxyapatite (HAp), which was confirmed by XRD and SEM analysis. Sand solidification experiments demonstrated improvements in unconfined compressive strength (UCS), especially at higher Urea/Ca²⁺ ratios. The UCS values obtained were 10.35 MPa at a ratio of 2.0, 3.34 MPa at a ratio of 1.0, and 0.43 MPa at a ratio of 0.5, highlighting the advantages of MICPP over traditional methods. Microstructural analysis further clarified the mineral composition, demonstrating the potential of MICPP in environmentally friendly soil engineering. The study highlights the promise of MICPP for sustainable soil stabilization, offering improved mechanical properties and reducing environmental impact, paving the way for novel geotechnical practices.

Biosynthesis of a Functional Silica-Based Biohybrid Material with High Pb(II) Capture Ability
Ilham Maulidin, Kazunori Nakashima, Ryo Naota, Anju Pilakka Veedu, Chikara Takano, Satoru Kawasaki
ACS Sustainable Resource Management, American Chemical Society (ACS), 2024年05月07日
研究論文（学術雑誌）

Combination of cellulose nanofiber and artificial fusion protein for biocementation
Thiloththama Hiranya Kumari Nawarathna, Jin Sakai, Kazunori Nakashima, Tetsuya Kawabe, Miki Shikama, Chikara Takano, Satoru Kawasaki
Frontiers in Built Environment, 9, Frontiers Media SA, 2024年01月08日
研究論文（学術雑誌）, Biomineralization occurring in living organisms is mostly controlled by organic macromolecules such as polysaccharides and proteins. Recently, biomineralization has been attracting much attention as a green and sustainable cementation technique including enzyme-induced carbonate precipitation (EICP), where CaCO₃ is formed by hydrolysis of urea by urease in the presence of calcium ions. In this study, we have developed a novel hybrid biocementation method combining CaCO₃ and cellulose nanofiber (CNF). In nature, matrix proteins work as a binder at the interface of organic and inorganic materials to form hybrid biomaterials. By mimicking the natural system, we designed an artificial fusion protein to facilitate the deposition of CaCO₃ on CNF. Calcite-binding peptide (CaBP) and carbohydrate-binding module (CBM) were introduced in the artificial fusion protein CaBP-CBM to connect CaCO₃ and cellulose. The addition of CNF in the EICP system resulted in the formation of a number of small particles of CaCO₃ compared to a non-additive system. The addition of the fusion protein CaBP-CBM to CNF led to an increase in the size of CaCO₃ particles. Furthermore, the combination of CaBP-CBM and CNF provides higher strength of samples in sand solidification. Therefore, introduction of CNF and the fusion protein would be promising for novel biocementation techniques.

Baseline investigation on enzyme induced calcium phosphate precipitation for solidification of sand
Sivakumar Gowthaman, Moeka Yamamoto, Meiqi Chen, Kazunori Nakashima, Satoru Kawasaki
Frontiers in Built Environment, 9:1307650, 2023年12月, ［査読有り］
英語, 研究論文（学術雑誌）

Eco-friendly soil stabilization method using fish bone as cement material
Maksym Avramenko, Kazunori Nakashima, Chikara Takano, Satoru Kawasaki
Science of The Total Environment, 900, 165823, 165823, Elsevier BV, 2023年11月, ［査読有り］
研究論文（学術雑誌）

Functional modification of mussel adhesive protein to control solubility and adhesion property
Anju Pilakka Veedu, Kazunori Nakashima, Hayahide Shiga, Takahiro Sato, Kasun Godigamuwa, Naoki Hiroyoshi, Satoru Kawasaki
Journal of Bioscience and Bioengineering, 136, 2, 87, 93, Elsevier BV, 2023年08月, ［査読有り］
研究論文（学術雑誌）

Baseline investigation on soil solidification through biocementation using airborne bacteria
Meiqi Chen, Sivakumar Gowthaman, Kazunori Nakashima, Chikara Takano, Satoru Kawasaki
Frontiers in Bioengineering and Biotechnology, 11, Frontiers Media SA, 2023年06月14日, ［査読有り］
研究論文（学術雑誌）, Microbial induced carbonate precipitation (MICP) through the ureolysis metabolic pathway is one of the most studied topics in biocementation due to its high efficiency. Although excellent outcomes have proved the potential of this technique, microorganisms face some obstacles when considering complicated situations in the real field, such as bacterial adaptability and survivability issues. This study made the first attempt to seek solutions to this issue from the air, exploring ureolytic airborne bacteria with resilient features to find a solution to survivability issues. Samples were collected using an air sampler in Sapporo, Hokkaido, a cold region where sampling sites were mostly covered with dense vegetation. After two rounds of screening, 12 out of 57 urease-positive isolates were identified through 16S rRNA gene analysis. Four potentially selected strains were then evaluated in terms of growth pattern and activity changes within a range of temperatures (15°C–35°C). The results from sand solidification tests using two Lederbergia strains with the best performance among the isolates showed an improvement in unconfined compressive strength up to 4–8 MPa after treatment, indicating a high MICP efficiency. Overall, this baseline study demonstrated that the air could be an ideal isolation source for ureolytic bacteria and laid a new pathway for MICP applications. More investigations on the performance of airborne bacteria under changeable environments may be required to further examine their survivability and adaptability.

Field experimentation of bio-cementation using low-cost cementation media for preservation of slope surface
Sivakumar Gowthaman, Hiromu Koizumi, Kazunori Nakashima, Satoru Kawasaki
Case Studies in Construction Materials, 18, e02086, 2023年04月, ［査読有り］
英語, 研究論文（学術雑誌）

SOIL IMPROVEMENT USING CALCIUM PHOSPHATE COMPOUNDS AS A NOVEL SUSTAINABLE METHOD: A REVIEW
Maksym Avramenko
International Journal of GEOMATE, 24, 101, International Journal of Geomate, 2023年01月30日, ［査読有り］
研究論文（学術雑誌）

Naturally Derived Cements Learned from the Wisdom of Ancestors: A Literature Review Based on the Experiences of Ancient China, India and Rome
Zhan Su, Zhen Yan, Kazunori Nakashima, Chikara Takano, Satoru Kawasaki
Materials, 16, 2, 603, 603, MDPI AG, 2023年01月08日, ［査読有り］
研究論文（学術雑誌）, For over a thousand years, many ancient cements have remained durable despite long-term exposure to atmospheric or humid agents. This review paper summarizes technologies of worldwide ancient architectures which have shown remarkable durability that has preserved them over thousands of years of constant erosion. We aim to identify the influence of organic and inorganic additions in altering cement properties and take these lost and forgotten technologies to the production frontline. The types of additions were usually decided based on the local environment and purpose of the structure. The ancient Romans built magnificent structures by making hydraulic cement using volcanic ash. The ancient Chinese introduced sticky rice and other local materials to improve the properties of pure lime cement. A variety of organic and inorganic additions used in traditional lime cement not only changes its properties but also improves its durability for centuries. The benefits they bring to cement may also be useful in enzyme-induced carbonate precipitation (EICP) and microbially induced carbonate precipitation (MICP) fields. For instance, sticky rice has been confirmed to play a crucial role in regulating calcite crystal growth and providing interior hydrophobic conditions, which contribute to improving the strength and durability of EICP- and MICP-treated samples in a sustainable way.

Interfacial biosilica coating of chitosan gel using fusion silicatein to fabricate robust hybrid material for biomolecular applications
Kasun Godigamuwa, Kazunori Nakashima, Sota Tsujitani, Ryo Naota, Ilham Maulidin, Satoru Kawasaki
Journal of Materials Chemistry B, 11, 8, 1654, 1658, Royal Society of Chemistry (RSC), 2023年, ［査読有り］
研究論文（学術雑誌）, An enzyme-encapsulated silica-based hybrid material was developed using a chitosan gel.

Valorization of tannery solid wastes for sustainable enzyme induced carbonate precipitation process
Parthasarathy Baskaran Sujiritha, Vijan Lal Vikash, George Sebastian Antony, Ganesan Ponesakki, Niraikulam Ayyadurai, Kazunori Nakashima, Numbi Ramudu Kamini
Chemosphere, 308, 136533, 136533, Elsevier BV, 2022年12月, ［査読有り］, ［国際共著］
研究論文（学術雑誌）

Polymer-assisted enzyme induced carbonate precipitation for non-ammonia emission soil stabilization
Zhen Yan, Sivakumar Gowthaman, Kazunori Nakashima, Satoru Kawasaki
Scientific Reports, 12, 1, Springer Science and Business Media LLC, 2022年12月, ［査読有り］
研究論文（学術雑誌）, Abstract

Biocementation using enzyme induced carbonate precipitation (EICP) process has become an innovative method for soil improvement. One of the major limitations in scaling-up of biocement treatment is the emission of gaseous ammonia during the urea hydrolysis, which is environmentally hazardous. In order to eliminate this shortcoming, this paper presents a series of experiments performed to evaluate a novel approach for preventing the ammonia byproducts in the EICP process via the use of polyacrylic acid (PAA). Through the adjustment of the pH to acidic, PAA not only promotes the enzyme activity, but also averts the conversion of ammonium to gaseous ammonia and its release, thus preventing any harm to the environment. The sand samples were treated with cementation solution and assessed for improvement in strength. Calcium carbonate content measurements and X-ray powder diffraction analysis identified the calcite crystals precipitated in the soil pores. Scanning electron microscopy analysis clearly showed that calcium carbonate was precipitated connecting soil particles, thus providing a uniaxial compressive strength (UCS) of up to 1.65 MPa. Overall, the inhibition in the speciation of gaseous ammonia shows the great potential of PAA for large-scale promotion of biocement.

Feasibility of bacterial-enzyme induced carbonate precipitation technology for stabilizing fine-grained slope soils
Sivakumar Gowthaman, Takashi Iki, Aoi Ichinohe, Kazunori Nakashima, Satoru Kawasaki
Frontiers in Built Environment, 8, Frontiers Media SA, 2022年10月12日, ［査読有り］
研究論文（学術雑誌）, Microbial Induced Carbonate Precipitation (MICP) has recently become a new technology for stabilizing the slope surface. The applicability of MICP, however, is limited in fine-grained soils due to the restrictions regarding the transportation of bacteria cells. The purpose of this study was to assess the feasibility of an alternative called Bacterial-Enzyme Induced Carbonate Precipitation (B-EICP) for stabilizing the fine-grained slope soils. Unlike the MICP strategy (involving whole-cells of bacteria), the proposed B-EICP utilizes bacterial urease to induce the bio-cement formation within soil. The whole-cell culture of Lysinibacillus xylanilyticus was subjected to cyclic sonication to extract the free urease suspension. The B-EICP treatment was performed to the columns prepared using two different soils obtained from representative expressway slopes. The cementation responses of the proposed B-EICP were compared with that of typical MICP method, especially from the following viewpoints, (i) adaptability to soil with high fine-grained content, (ii) conditions under which B-EICP can be effectively applied and (iii) cementation under low temperature. The results revealed that the extract solution had higher urease activity compared to original bacteria culture, and the activity remained more stable at low temperature conditions (15°C). The results further confirmed that B-EICP method is more suitable for stabilizing soils with large amount of fine particles. Comparing with MICP, the B-EICP resulted higher unconfined compressive strength (over 1200 kPa) and deeper cementation in the silty sand. Microscale analysis suggested that the B-EICP could induce smaller calcium carbonate crystals than that by MICP, but the number of crystals in B-EICP were significantly more, thus contributed to increased particle-particle cementation.

State-of-the-Art Review on Engineering Uses of Calcium Phosphate Compounds: An Eco-Friendly Approach for Soil Improvement
Maksym Avramenko, Kazunori Nakashima, Satoru Kawasaki
Materials, 15, 19, 6878, 6878, MDPI AG, 2022年10月03日, ［査読有り］
研究論文（学術雑誌）, Greenhouse gas emissions are a critical problem nowadays. The cement manufacturing sector alone accounts for 8% of all human-generated emissions, and as the world’s population grows and globalization intensifies, this sector will require significantly more resources. In order to fulfill the need of geomaterials for construction and to reduce carbon dioxide emissions into the atmosphere, conventional approaches to soil reinforcement need to be reconsidered. Calcium phosphate compounds (CPCs) are new materials that have only recently found their place in the soil reinforcement field. Its eco-friendly, non-toxic, reaction pathway is highly dependent on the pH of the medium and the concentration of components inside the solution. CPCs has advantages over the two most common environmental methods of soil reinforcement, microbial-induced carbonate precipitation (MICP) and enzyme induced carbonate precipitation (EICP); with CPCs, the ammonium problem can be neutralized and thus allowed to be applied in the field. In this review paper, the advantages and disadvantages of the engineering uses of CPCs for soil improvement have been discussed. Additionally, the process of how CPCs perform has been studied and an analysis of existing studies related to soil reinforcement by CPC implementation was conducted.

Influence of humic acid on microbial induced carbonate precipitation for organic soil improvement
Meiqi Chen, Sivakumar Gowthaman, Kazunori Nakashima, Satoru Kawasaki
Environmental Science and Pollution Research, 30, 6, 15230, 15240, Springer Science and Business Media LLC, 2022年09月27日, ［査読有り］
研究論文（学術雑誌）

Effect of wetting and drying cycles on the durability of bio-cemented soil of expressway slope
S. Gowthaman, K. Nakashima, S. Kawasaki
International Journal of Environmental Science and Technology, 19, 4, 2309, 2322, Springer Science and Business Media LLC, 2022年04月, ［査読有り］
研究論文（学術雑誌）, Abstract

Cyclic wet-dry is one of the influential weathering agents which can rapidly alter the mechanical properties of soils, limiting their durability and consistent performance. This study investigates the effect of wet-dry cycles on the mechanical behaviour of bio-cemented soil. Microbial-induced carbonate precipitation-based bio-cementation is an innovative soil improvement method, which is gaining increasing attention as a potential alternative for stabilizing slope surface. As the treated surfaces are exposed to repeated rainfalls and draughts, durability analysis is essential; cyclic wet-dry tests were therefore performed as a credible indicator of durability. The soil obtained from the Hokkaido expressway slope was treated at laboratory to varying cementation levels (% CaCO₃) and subjected to 50 subsequent wet-dry cycles. Physical and mechanical changes were monitored using mass loss, shear wave velocities and needle penetration tests during wet-dry cycles. The results showed that the wet-dry cycles deteriorated the physical and mechanical at two stages. The mass and S-wave velocity of specimens significantly dropped after first few cycles and then tended to reach equilibrium. The second stage of notable deterioration was observed between 30 and 50 wet-dry cycles. It is suggested that the erosion of weak and powdery deposition of CaCO₃ causes the degradation at the early stage, whereas the degradation in the late stage was attributed to the microstructural deformations of intact carbonate bonds. It was also found that the increase in cementation level decreases the deterioration of bio-cemented soil under wet-dry cycles.

Durability Improvement of Biocemented Sand by Fiber-Reinforced MICP for Coastal Erosion Protection
Md Al Imran, Kazunori Nakashima, Niki Evelpidou, Satoru Kawasaki
Materials, 15, 7, 2389, 2389, MDPI AG, 2022年03月24日, ［査読有り］
研究論文（学術雑誌）, Soil improvement via MICP (microbially induced carbonate precipitation) technologies has recently received widespread attention in the geoenvironmental and geotechnical fields. The durability of MICP-treated samples remains a critical concern in this novel method. In this work, fiber (jute)-reinforced MICP-treated samples were investigated to evaluate their durability under exposure to distilled water (DW) and artificial seawater (ASW), so as to advance the understanding of long-term performance mimicking real field conditions, along with improvement of the MICP-treated samples for use in coastal erosion protection. Primarily, the results showed that the addition of fiber (jute) improved the durability of the MICP-treated samples by more than 50%. Results also showed that the wet–dry (WD) cyclic process resulted in adverse effects on the mechanical and physical characteristics of fiber-reinforced MICP-treated samples in both DW and ASW. The breakdown of calcium carbonates and bonding effects in between the sand particles was discovered to be involved in the deterioration of MICP samples caused by WD cycles, and this occurs in two stages. The findings of this study would be extremely beneficial to extend the insight and understanding of improvement and durability responses for significant and effective MICP treatments and/or re-treatments.

Solubilization and aggregation control of silica-polymerizing enzyme fused with a removable soluble protein
Hidetoshi Oguri, Kazunori Nakashima, Kasun Godigamuwa, Junnosuke Okamoto, Yudai Takeda, Fumiyoshi Okazaki, Masafumi Sakono, Satoru Kawasaki
Journal of Bioscience and Bioengineering, 133, 3, 222, 228, Elsevier BV, 2022年03月, ［査読有り］
研究論文（学術雑誌）

Calcium phosphate biocement using bone meal and acid urease: An eco-friendly approach for soil improvement
Sivakumar Gowthaman, Moeka Yamamoto, Kazunori Nakashima, Volodymyr Ivanov, Satoru Kawasaki
Journal of Cleaner Production, 319, 128782, 128782, Elsevier BV, 2021年10月, ［査読有り］
研究論文（学術雑誌）

Removal of ammonium by-products from the effluent of bio-cementation system through struvite precipitation
Sivakumar Gowthaman, Arash Mohsenzadeh, Kazunori Nakashima, Satoru Kawasaki
Materials Today: Proceedings, Elsevier BV, 2021年09月, ［査読有り］
研究論文（学術雑誌）

Experimental Study on Sand Stabilization Using Bio-Cementation with Wastepaper Fiber Integration
Meiqi Chen, Sivakumar Gowthaman, Kazunori Nakashima, Shin Komatsu, Satoru Kawasaki
MATERIALS, 14, 18, MDPI, 2021年09月, ［査読有り］
英語, 研究論文（学術雑誌）, Recently, green materials and technologies have received considerable attention in geotechnical engineering. One of such techniques is microbially-induced carbonate precipitation (MICP). In the MICP process, CaCO3 is achieved bio-chemically within the soil, thus enhancing the strength and stiffness. The purpose of this study is to introduce the wastepaper fiber (WPF) onto the MICP (i) to study the mechanical properties of MICP-treated sand with varying WPF content (0-8%) and (ii) to assess the freeze-thaw (FT) durability of the treated samples. Findings revealed that the ductility of the treated samples increases with the increase in WPF addition, while the highest UCS is found with a small fiber addition. The results of CaCO3 content suggest that the WPF addition enhances the immobilization of the bacteria cells, thus yielding the precipitation content. However, shear wave velocity analysis indicates that a higher addition of WPF results in rapid deterioration of the samples when subjected to freeze-thaw cycles. Microscale analysis illuminates that fiber clusters replace the solid bonding at particle contacts, leading to reduced resistance to freeze-thaw damage. Overall, the study demonstrates that as a waste material, WPF could be sustainably reused in the bio-cementation.

Fabrication of silica on chitin in ambient conditions using silicatein fused with a chitin-binding domain
Kasun Godigamuwa, Kazunori Nakashima, Sota Tsujitani, Satoru Kawasaki
BIOPROCESS AND BIOSYSTEMS ENGINEERING, 44, 9, 1883, 1890, SPRINGER, 2021年09月, ［査読有り］
英語, 研究論文（学術雑誌）, High temperatures, harsh pH conditions, and toxic chemicals involved in the conventional synthesis and coating of silica limit the fabrication of new-generation hybrid materials immobilizing live cells and biomolecules such as enzymes and drugs. This hinders the application of inorganic-organic biohybrid materials in various fields, including bioelectronics, energy generation, and biomedicine. Silicatein, an enzyme found in siliceous sponges, catalyzes the polymerization of silica under mild conditions, that is, at room temperature and neutral pH. Silicatein was fused with a chitin-binding domain (ChBD) to selectively bind the fusion silicatein on the chitin material and with a small soluble tag called InakC, a hydrophilic protein from Pseudomonas syringae, to control the unfavorable aggregation of silicatein. The fusion silicatein was soluble in aqueous media and was successfully found to be adsorbed on the chitin material. The immobilized fusion silicatein acted as an interfacial catalyst to fabricate silica on chitin under ambient conditions. This technique can be used to fabricate inorganic-organic hybrid materials to immobilize biomolecules and can be applied to develop novel biocatalytic systems, biosensors, and tissue culture scaffolds.

Durability analysis of bio-cemented slope soil under the exposure of acid rain
Sivakumar Gowthaman, Kazunori Nakashima, Satoru Kawasaki
JOURNAL OF SOILS AND SEDIMENTS, 21, 8, 2831, 2844, SPRINGER HEIDELBERG, 2021年08月, ［査読有り］
英語, 研究論文（学術雑誌）, Purpose Instability of slope surface is a critical concern in Geotechnical and Environmental Engineering. MICP (Microbial-Induced Carbonate Precipitation), an innovative bio-cementation technique, has attracted the attention for slope surface protection. In this work, MICP was investigated to evaluate its durability under the exposure of acid rain and to advance the understanding on long-term performance of slope soil preserved by MICP. Methods MICP treatment was applied to a fine-grained slope soil using indigenous bacteria. Specimens treated to different cementation levels (% CaCO3) were exposed to acid rain (of varying pH) through two sorts of mechanisms: (i) infiltration and (ii) immersion. The evaluations were based on corrosion of CaCO3, mass loss, needle penetration tests, and scanning electron microscopy. Results The decrease in pH increased the corrosion of CaCO3, resulting in considerable loss in aggregate and unconfined compressive strength. However, increased cementation level showed high durability of specimens. The soils treated to 12.5% CaCO3 showed 19.9% soil loss, whereas it was reduced to 5.4% when cemented to 22.5% CaCO3. The results also revealed that the contact time of acid rain significantly governed the rate of corrosion, i.e., specimens subjected to lower infiltration rate (20 mm/h) showed higher loss of mass compared to that of higher rate (100 mm/h). Conclusion The long-term performance of MICP treatment is determined by (i) cementation level, (ii) pH, and (iii) infiltration rate of acid rain. High cementation level promotes the longevity of the treatment. Therefore, MICP to higher cementation level is recommended for long-term preservation of slope surface.

Artificial Fusion Protein to Facilitate Calcium Carbonate Mineralization on Insoluble Polysaccharide for Efficient Biocementation
Thiloththama H. K. Nawarathna, Kazunori Nakashima, Tetsuya Kawabe, Wilson Mwandira, Kiyofumi Kurumisawa, Satoru Kawasaki
ACS SUSTAINABLE CHEMISTRY & ENGINEERING, 9, 34, 11493, 11502, AMER CHEMICAL SOC, 2021年08月, ［査読有り］
英語, 研究論文（学術雑誌）, Biomineralization is a process of mineral formation in living organisms. Compared with nonbiogenic minerals, biominerals can be defined as organic-inorganic hybrid materials that have excellent physical and optical properties. In the current study, an artificial protein mimicking the outer shell of crayfish, composed of CaCO3, chitin, and proteins, was developed to facilitate organic-inorganic hybrid material formation by precipitation of calcium carbonate on the chitin matrix. The fusion protein (CaBP-ChBD) was constructed by introducing a short-sequence calcite-binding peptide (CaBP) into the chitin-binding domain (ChBD). Calcium carbonate precipitation experiments by enzymatic urea hydrolysis revealed that a significant increase in the CaCO3 formation was achieved by adding CaBP-ChBD. Also, CaCO3 was efficiently deposited on chitin particles decorated with CaBP-ChBD. Most interestingly, CaBP-ChBD would improve the performance in sand solidification more efficiently and sustainably in the process of biocementation technique. The developed recombinant protein could be used for the sustainable production of organic-inorganic green materials for engineering applications.

Effect of Scallop Powder Addition on MICP Treatment of Amorphous Peat
Sivakumar Gowthaman, Meiqi Chen, Kazunori Nakashima, Satoru Kawasaki
FRONTIERS IN ENVIRONMENTAL SCIENCE, 9, FRONTIERS MEDIA SA, 2021年07月, ［査読有り］
英語, 研究論文（学術雑誌）, Peat is one of the most challenging and problematic soils in the fields of geotechnical and environmental engineering. The most critical problems related to peat soils are extremely low strength and high compressibility, resulting in poor inhabitancy and infrastructural developments in their vicinity. Thus far, peat soils were stabilized using Portland cement; however, the production of Portland cement causes significant emission of greenhouse gases, which is not environmentally desirable. Microbial-induced carbonate precipitation (MICP) is an innovative technique for improving the mechanical properties of soil through potentially environmentally friendly processes. This article presents a laboratory study carried out with the aim of investigating the viability and effect of scallop shell powder (SSP) on enhancing the mechanical properties of the MICP-treated amorphous peat. The hypothesis was that the distribution of SSP (as-derived calcite particles) would (i) provide more nucleation sites to precipitates and (ii) increase the connectivity of MICP bridges to facilitate mineral skeleton to amorphous peat, accompanied by an increase in its compressive strength. Specimens were treated at varying combinations of SSP and MICP reagents, and the improvement was comprehensively assessed through a series of unconfined compression tests and supported by microscale and chemical analyses such as scanning electron microscopy, energy-dispersive X-ray analysis, and X-ray diffraction analysis. The outcomes showed that incorporating SSP in MICP treatment would be a promising approach to treat amorphous peat soils. The proposed approach could improve the unconfined compressive strength by over 200% after a 7-day curing period, while the conventional MICP could not exhibit any significant improvements.

Bio-Mediated Soil Improvement Using Plant Derived Enzyme in Addition to Magnesium Ion
Md Al Imran, Kazunori Nakashima, Satoru Kawasaki
CRYSTALS, 11, 5, MDPI, 2021年05月, ［査読有り］
英語, 研究論文（学術雑誌）, Recently, soil improvement using EICP (Enzyme-Induced Carbonate Precipitation) methods in the geotechnical and geo-environmental field has become a prominent interest worldwide. The objective of this study was to develop an improved extraction technique of crude urease from watermelon seeds in both dry and germinated conditions. Subsequently, this study also analyzed the improvement methodology of crystal polymorphs and soil bonding incorporation of various Mg2+/Ca2+ ratios. The optimization of enzyme-mediated carbonate precipitation was also investigated by Scanning Electron Microscope (SEM) and X-ray Diffraction (XRD) analysis. Results confirmed that the precipitated crystals are mainly calcite, vaterite and aragonite primarily (depending on the Mg2+/Ca2+ ratios). Therefore, to improve the bonding capacity in between the sand particles a novel improvement methodology was investigated by adding various Mg2+/Ca2+ ratios. The mechanical properties of the treated soil (Mikawa Sand, D-50 = 0.870 mm) specimens were tested by unconfined compressive strength (UCS) and this confirmed the effectiveness of adding various Mg2+/Ca2+ ratios. The results of the UCS tests showed that, the lower molar ratios of Mg2+/Ca2+ can significantly improve the UCS of the specimen (up to 50%) which could be considered a significant outcome for different bio-geotechnical applications.

Shoreline mapping based on beachrocks identification in Krakal-Sadranan beach, Yogyakarta, Indonesia
Lutfian R. Daryono, Kazunori Nakashima, Satoru Kawasaki, Anastasia D. Titisari, Didit H. Barianto, Imam Suyanto, Arief Rahmadi
BULLETIN OF ENGINEERING GEOLOGY AND THE ENVIRONMENT, 80, 3, 2825, 2844, SPRINGER HEIDELBERG, 2021年03月, ［査読有り］
英語, 研究論文（学術雑誌）, A great deal of progress has been made in recent years to investigate the chemical characteristics of beachrocks. Beachrocks found in Krakal-Sadranan Beach (Yogyakarta, Indonesia) are spread locally, parallel to the coastline with a breadth of about 10-30 m(2). In this research, unmanned aerial vehicle (UAV) drone mapping, geological analysis, direct current resistivity survey, and surface seismic surveys were conducted to detect the underground structure of the beachrocks and to emphasize the coastal mapping based on targeted beachrocks. The correlation was developed between the sections and the data on the study site. Toward survey validation, laboratory tests were conducted on the beachrock samples collected from the study site to identify its properties. The evolution of the coastal zone based on beachrocks study is highly affected by relative sea-level changes that were described in the 3D model of beachrocks. The coastal changes are significantly impact the natural and cultural resources, and the understanding of coastal evolution is important for the preservation, development, and management of the coastal zone. This paper focused on the cementation processes and mechanism of beachrocks as a natural wave barrier in a tropical area, which is also appropriate for advanced marine ecosystems study including shorelines microbiotas.

IMPROVEMENT OF USING CRUDE EXTRACT UREASE FROM WATERMELON SEEDS FOR BIOCEMENTATION TECHNOLOGY
Md Al Imran, Kazunori Nakashima, Niki Evelpidou, Satoru Kawasaki
INTERNATIONAL JOURNAL OF GEOMATE, 20, 78, 142, 147, GEOMATE INT SOC, 2021年02月, ［査読有り］
英語, 研究論文（学術雑誌）, In recent years, the formation of artificial beachrock and bio-cementation method has gained considerable attention as a sustainable alternative tool in the area of geotechnical and geo-environmental engineering field for soil improvement and construction materials. In general, earlier methods of soil improvement were mostly concentrated on microbes (Bacteria, Fungi, etc.) as a source of urease enzyme widely known as MICP method (Microbial Induced Carbonate Precipitation). To address some of the key limitations of MICP method this study focused on using crude enzyme (low cost, eco-friendly). Crude enzyme was extracted from watermelon seeds (Citrullus lanatus) considered as "food waste material" and the carbonate formation process known as EICP "Enzyme Induced Carbonate Precipitation." Crushed and blended watermelon seeds (both dry and germinated) used as a source of urease enzyme. Subsequently, their urease activity was also investigated with various environmental parameters (Temperature, pH, etc.) and investigated the carbonate precipitation trend using calcium chloride (CaCl2) and urea [ (CO(NH2)(2)]. The form of carbonate (calcite, aragonite, vaterite, etc.) was also confirmed by XRD and SEM-EDX analysis. Finally, syringe (d = 2.3 cm, h= 7.1 cm) sand solidification test was conducted using commercially available "Mikawa sand" (mean diameter, D-50 = 870 mm) and successfully achieved unconfined compressive strength (UCS) of about 1.2 MPa at neutral pH (similar to 7) and temperature condition (30 degrees C) considering various curing days and conditions. This study could be useful as an eco-friendly and sustainable method for numerous bio-geotechnical applications (for instance, ground improvement, liquefaction mitigation, artificial beach rock formations, coastal erosion protection, etc.) and the extracted crude urease from watermelon seeds could play as an alternative to replace commercially available urease for carbonate precipitation.

EVALUATING MECHANICAL STRENGTH OF PEAT SOIL TREATED BY FIBER INCORPORATED BIO-CEMENTATION
Meiqi Chen, Sivakumar Gowthaman, Kazunori Nakashima, Satoru Kawasaki
INTERNATIONAL JOURNAL OF GEOMATE, 20, 78, 121, 127, GEOMATE INT SOC, 2021年02月, ［査読有り］
英語, 研究論文（学術雑誌）, Peat soil is an accumulation of partially decayed vegetation, formed under the condition of nearly permanent water saturation, which makes the high moisture and compressibility as two main features of peat. In recent years, the lack of construction lands diverts researchers' attention to make use of marginal grounds, like peatland, after some improvements. The past decade has witnessed a growing interest in microbial induced carbonate precipitation (MICP) due to its reliability, broad application, and potential contribution to sustainable and green development. This study has two primary aims: (i) investigating the feasibility and effectiveness of MICP in peat soil combined with bamboo fiber reinforcement, and (ii) ascertaining the mechanism of bamboo fiber incorporated MICP. Bamboo fiber possesses some unparalleled advantages owing to its fast growth and ability to survive in diverse climates. This study differs from previous researches in the use of native bacteria isolated from the peat soil, while most of them were conducted using exogenous bacteria, which might pose a threat regarding adaption and microbial pollution. Different concentrations of cementation resources (1-3 mol/L) and proportion of fibers (0-50%) were studied, and each case was well designed. Treated samples were subjected to the fall cone test to estimate the undrained shear strength at certain time intervals. The results revealed that samples with higher fiber content gained higher strength than others did, whereas high initial cementation resources in soil could reduce strength. Microscale observations were also performed on treated samples to clarify the mechanism of MICP incorporated with fiber.

A two-stage treatment process for the management of produced ammonium by-products in ureolytic bio-cementation process
A. Mohsenzadeh, E. Aflaki, S. Gowthaman, K. Nakashima, S. Kawasaki, T. Ebadi
International Journal of Environmental Science and Technology, Springer Science and Business Media LLC, 2021年01月27日, ［査読有り］
研究論文（学術雑誌）

Biosorption of Pb (II) and Zn (II) from aqueous solution by Oceanobacillus profundus isolated from an abandoned mine
Wilson Mwandira, Kazunori Nakashima, Satoru Kawasaki, Allison Arabelo, Kawawa Banda, Imasiku Nyambe, Meki Chirwa, Mayumi Ito, Tsutomu Sato, Toshifumi Igarashi, Hokuto Nakata, Shouta Nakayama, Mayumi Ishizuka
Scientific Reports, 10, 1, 21189, Springer Science and Business Media LLC, 2020年12月, ［査読有り］
研究論文（学術雑誌）, The present study investigated biosorption of Pb (II) and Zn (II) using a heavy metal tolerant bacterium Oceanobacillus profundus KBZ 3-2 isolated from a contaminated site. The effects of process parameters such as effect on bacterial growth, pH and initial lead ion concentration were studied. The results showed that the maximum removal percentage for Pb (II) was 97% at an initial concentration of 50 mg/L whereas maximum removal percentage for Zn (II) was at 54% at an initial concentration of 2 mg/L obtained at pH 6 and 30 °C. The isolated bacteria were found to sequester both Pb (II) and Zn (II) in the extracellular polymeric substance (EPS). The EPS facilitates ion exchange and metal chelation-complexation by virtue of the existence of ionizable functional groups such as carboxyl, sulfate, and phosphate present in the protein and polysaccharides. Therefore, the use of indigenous bacteria in the remediation of contaminated water is an eco-friendly way of solving anthropogenic contamination.

Applications of Chitosan in Environmental Remediation: A Short Review
Preeti Pal, Anjali Pal, Kazunori Nakashima, Brijesh Kumar Yadav
Chemosphere, 266, PERGAMON-ELSEVIER SCIENCE LTD, 2020年11月, ［査読有り］, ［国際共著］
英語, Environmental biotechnology is the use of biotechnology to develop and regulate biological systems for the remediation of environmental contamination. Nature has gifted ample material for remediation of its resources, among which chitosan is one of the most important and largely available biomaterial globally. Chitosan is a biopolymer obtained by deacetylation of chitin extracted from marine waste and its applications from drug delivery to food additives are broadly available. Chitosan exhibit several properties such as availability, low cost, high biocompatibility, and biodegradability. These properties make it biologically and chemically acceptable for use in various fields. Due to some limitations of pure chitosan, there has been a growing interest in modifying the chitosan in order to improve the original properties and widen the applications of pure phase chitosan. Various modified forms of chitosan and their associated applications are reviewed here with emphasis on their use in environmental remediation. The demand of chitosan in the global industrial market is growing which is briefly explained in this paper. Chitosan is used for water purification since a long time and still progress is going on for making it more efficient in the removal process. It can be used as a flocculent and coagulant, as an adsorbent for removing the contaminants like heavy metals, dyes, pesticides, antibiotics, biological contaminants from wastewater. Soil remediation using chitosan material is explained in this review. Various other applications such as drug delivery, food additives, tissue engineering are thoroughly reviewed. (C) 2020 Elsevier Ltd. All rights reserved.

Distribution and cementation characteristics of beachrocks along southern, southwestern and western coast of Sri Lanka
Pahala Ge, Nishadi Nayanthara, Anjula Buddhika, Nayomi Dassanayake, Kazunori Nakashima, Satoru Kawasaki
Journal of Sedimentary Environments, 6, 1, 93, 106, SPRINGER HEIDELBERG, 2020年11月, ［査読有り］
英語, 研究論文（学術雑誌）, Beachrocks are sedimentary structures where gravelly or sandy beaches have been transformed into rock outcrops formed through precipitation of connective cements amid their interstices. They are well-noted coastal features along the coastal belt of Sri Lanka due to the prevalent tropical climate. This study was aimed at gathering data on surface nature and cementation characteristics of beachrock occurrences along a part of Sri Lankan shoreline through field observations and a series of analyses including X-ray diffraction, X-ray fluorescence, scanning electron microscopy (SEM) techniques and petrographic thin-section analysis. The combined research findings from different techniques are also employed as a preliminary step to determine the formation mechanism of the studied beachrocks. The seaward-inclined low-angle beds running parallel to present shoreline are composed mostly of sandstone with occasional conglomerate. Almost all the beachrocks are made of quartz grains amalgamated by cement. One remarkable feature of Sri Lankan beachrocks is the presence of heavy minerals generally in thin lamina form. The cementing agents are predominantly composed of metastable carbonate phases, high magnesium calcite (HMC) and aragonite (Ar) with varying microfabrics and textures. From SEM examinations and thin-section images, main morphologies identified are acicular Ar, scalenohedral magnesium calcites along with bridge cements and micritic coatings which are typical of a marine-phreatic precipitation with the exception of occasional meniscus cements. Further, the presence of evidences of living organisms may be an indication of influence from the biological aspects which can be confirmed by more detailed analyses.

The Influence of the Addition of Plant-Based Natural Fibers (Jute) on Biocemented Sand Using MICP Method　　　　　　　　　　　　　　　
Md Al Imran, Sivakumar Gowthaman, Kazunori Nakashima, Satoru Kawasaki
Materials, 13, 18, 4198, 2020年09月, ［査読有り］

Freeze-Thaw Durability and Shear Responses of Cemented Slope Soil Treated by Microbial Induced Carbonate Precipitation
Gowthaman, S, Nakashima, K, Kawasaki, S
Soils and Foundations, 60, 4, 840, 855, Elsevier BV, 2020年08月, ［査読有り］
研究論文（学術雑誌）

Biological route to fabricate silica on cellulose using immobilized silicatein fused with a carbohydrate-binding module
Kasun Godigamuwa, Kazunori Nakashima, Junnosuke Okamoto, Satoru Kawasaki
Biomacromolecules, American Chemical Society (ACS), 2020年06月16日, ［査読有り］
研究論文（学術雑誌）

Cellulose-metallothionein biosorbent for removal of Pb(II) and Zn(II) from polluted water　　　　　　　　　　　　　　　
Wilson Mwandira, Kazunori Nakashima, Yuki Togo, Tsutomu Sato, Satoru Kawasaki
Chemosphere, 246, 125733, 2020年05月, ［査読有り］
英語, 研究論文（学術雑誌）

Investigation of natural beachrock and physical-mechanical comparison with artificial beachrock induced by MICP as a protective measure against beach erosion at Yogyakarta, Indonesia　　　　　　　　　　　　　　　
Lutfian R. Daryono, Kazunori Nakashima, Satoru Kawasaki, Koichi Suzuki, Imam Suyanto, Arief Rahmadi
Geosciences, 10, 4, 143, 2020年04月, ［査読有り］
英語, 研究論文（学術雑誌）

A novel metal adsorbent composed of hexa-histidine tag and carbohydrate-binding module on cellulose　　　　　　　　　　　　　　　
Yuki Togo, Kazunori Nakashima, Wilson Mwandira, Satoru Kawasaki
Analytical Sciences, 36, 4, 459, 464, 2020年04月, ［査読有り］
英語, 研究論文（学術雑誌）

Microbial Leaching of Iron from Hematite: Direct or Indirect Elution　　　　　　　　　　　　　　　
Apichaya Aneksampant, Kazunori Nakashima, Satoru Kawasaki
Materials Transactions, 61, 2, 396, 401, 2020年02月, ［査読有り］
英語, 研究論文（学術雑誌）

Sediment characteristics of beachrock: A baseline investigation based on microbial induced carbonate precipitation at Krakal-Sadranan Beach, Yogyakarta, Indonesia　　　　　　　　　　　　　　　
Lutfian Rusdi Daryono, Kazunori Nakashima, Satoru Kawasaki, Anastasia Dewi Titisari, Didit Hadi Barianto
Applied Sciences, 10, 2, 520, 2020年01月, ［査読有り］
英語, 研究論文（学術雑誌）

Feasibility study for slope soil stabilization by microbial induced carbonate precipitation (MICP) using indigenous bacteria isolated from cold subarctic region　　　　　　　　　　　　　　　
Sivakumar Gowthaman, Takashi Iki, Kazunori Nakashima, Koji Ebina, Satoru Kawasaki
SN Applied Sciences, 1, 11, 1480, 2019年11月, ［査読有り］
英語, 研究論文（学術雑誌）

Feasibility Study of Native Ureolytic Bacteria for Biocementation Towards Coastal Erosion Protection by MICP Method　　　　　　　　　　　　　　　
Md Al Imran, Shuya Kimura, Kazunori Nakashima, Niki Evelpidou, Satoru Kawasaki
Applied Sciences, 9, 20, 4462, 2019年10月, ［査読有り］

A novel sustainable approach for coastal erosion protection through biocementation　　　　　　　　　　　　　　　
Md Al Imran, Shuya Kimura, Kazunori Nakashima, Niki Evelpidou, Satoru Kawasaki
Applied Sciences, 9, 20, 4462, 2019年10月, ［査読有り］
英語, 研究論文（学術雑誌）

Solidification of sand by Pb(II)-tolerant bacteria for capping mine waste to control metallic dust: Case of the abandoned Kabwe Mine, Zambia.
Wilson Mwandira, Kazunori Nakashima, Satoru Kawasaki, Mayumi Ito, Tsutomu Sato, Toshifumi Igarashi, Meki Chirwa, Kawawa Banda, Imasiku Nyambe, Shouta Nakayama, Hokuto Nakata, Mayumi Ishizuka
Chemosphere, 228, 17, 25, 2019年08月, ［査読有り］, ［国際誌］
英語, 研究論文（学術雑誌）, Environmental impacts resulting from historic lead and zinc mining in Kabwe, Zambia affect human health due to the dust generated from the mine waste that contains lead, a known hazardous pollutant. We employed microbially induced calcium carbonate precipitation (MICP), an alternative capping method, to prevent dust generation and reduce the mobility of contaminants. Pb-resistant Oceanobacillus profundus KBZ 1-3 and O. profundus KBZ 2-5 isolated from Kabwe were used to biocement the sand that would act as a cover to prevent dust and water infiltration. Sand biocemented by KBZ 1-3 and KBZ 2-5 had maximum unconfined compressive strength values of 3.2 MPa and 5.5 MPa, respectively. Additionally, biocemented sand exhibited reduced water permeability values of 9.6 × 10-8 m/s and 8.9 × 10-8 m/s for O. profundus KBZ 1-3 and KBZ 2-5, respectively, which could potentially limit the entrance of water and oxygen into the dump, hence reducing the leaching of heavy metals. We propose that these isolates represent an option for bioremediating contaminated waste by preventing both metallic dust from becoming airborne and rainwater from infiltrating into the waste. O. profundus KBZ 1-3 and O. profundus KBZ 2-5 isolated form Kabwe represent a novel species that has, for the first time, been applied in a bioremediation study.

Efficacy of biocementation of lead mine waste from the Kabwe Mine site evaluated using Pararhodobacter sp.
Wilson Mwandira, Kazunori Nakashima, Satoru Kawasaki, Mayumi Ito, Tsutomu Sato, Toshifumi Igarashi, Kawawa Banda, Meki Chirwa, Imasiku Nyambe, Shouta Nakayama, Mayumi Ishizuka
Environmental science and pollution research international, 26, 15, 15653, 15664, 2019年05月, ［査読有り］, ［国際誌］
英語, 研究論文（学術雑誌）, Biocementation of hazardous waste is used in reducing the mobility of contaminants, but studies on evaluating its efficacy have not been well documented. Therefore, to evaluate the efficacy of this method, physicochemical factors affecting stabilized hazardous products of in situ microbially induced calcium carbonate precipitation (MICP) were determined. The strength and leach resistance were investigated using the bacterium Pararhodobacter sp. Pb-contaminated kiln slag (KS) and leach plant residue (LPR) collected from Kabwe, Zambia, were investigated. Biocemented KS and KS/LPR had leachate Pb concentrations below the detection limit of < 0.001 mg/L, resisted slaking, and had maximum unconfined compressive strengths of 8 MPa for KS and 4 MPa for KS/LPR. Furthermore, biocemented KS and KS/LPR exhibited lower water absorption coefficient values, which could potentially reduce the water transportation of Pb2+. The results of this study show that MICP can reduce Pb2+ mobility in mine wastes. The improved physicochemical properties of the biocemented materials, therefore, indicates that this technique is an effective tool in stabilizing hazardous mine wastes and, consequently, preventing water and soil contamination.

Microbial Induced Carbonate Precipitation Using a Native Inland Bacterium for Beach Sand Stabilization in Near Shore Areas
Pahala Ge, Nishadi Nayanthara, Anjula Buddhika, Nayomi Dassanayake, Kazunori Nakashima, Satoru Kawasaki
Applied Sciences, 9, 3201, 2019年, ［査読有り］

Biocementation of Sri Lankan beach sand using locally isolated bacteria: A baseline study on the effect of segregated culture media
Pahala Ge, Nishadi Nayanthara, Anjula Buddhika, Nayomi Dassanayake, Kazunori Nakashima, Satoru Kawasaki
International Journal of GEOMATE, 17, 55, 62, 2019年, ［査読有り］

Chitosan enhances calcium carbonate precipitation and solidification mediated by bacteria
Thiloththama Hiranya, Kumari Nawarathna, Kazunori Nakashima, Satoru Kawasaki
International Journal of Biological Macromolecules, 133, 867, 874, 2019年, ［査読有り］

Microbial induced slope surface stabilization using industrial-grade chemicals: A preliminary laboratory study
Sivakumar Gowthaman, Shumpei Mitsuyama, Kazunori Nakashima, Masahiro Komatsu, Satoru Kawasaki
International Journal of GEOMATE, 17, 110, 116, 2019年, ［査読有り］

Factors Affecting the Urease Activity of Native Ureolytic Bacteria Isolated from Coastal Areas
Md Al Imran, Kazunori Nakashima, Niki Evelpidou, Satoru Kawasak
Geomechanics and Engineering, 17, 421, 427, 2019年, ［査読有り］

Biogeotechnical Approach for Slope Soil Stabilization Using Locally Isolated Bacteria and Inexpensive Low-grade Chemicals: A Feasibility Study on Hokkaido Expressway Soil, Japan
Sivakumar Gowthaman, Shumpei Mitsuyama, Kazunori Nakashima, Masahiro Komatsu, Satoru Kawasaki
Soils and Foundations, 59, 484, 499, 2019年, ［査読有り］

Bio-based cementation using urease-producing bacteria: Sand solidification and kinetics　　　　　　　　　　　　　　　
K. Nakashima, M. Fujita, T. H. K. Nawarathna, S. Kawasaki
New Biotechnology, 44, s154, 2018年10月, ［査読有り］
英語, 研究論文（国際会議プロシーディングス）

A state-of-the-art review on soil reinforcement technology using natural plant fiber materials: Past findings, present trends and future directions
Sivakumar Gowthaman, Kazunori Nakashima, Satoru Kawasaki
Materials, 11, 4, 553, MDPI AG, 2018年04月04日, ［査読有り］
英語, 研究論文（学術雑誌）, Incorporating sustainable materials into geotechnical applications increases day by day due to the consideration of impacts on healthy geo-environment and future generations. The environmental issues associated with conventional synthetic materials such as cement, plastic-composites, steel and ashes necessitate alternative approaches in geotechnical engineering. Recently, natural fiber materials in place of synthetic material have gained momentum as an emulating soil-reinforcement technique in sustainable geotechnics. However, the natural fibers are innately different from such synthetic material whereas behavior of fiber-reinforced soil is influenced not only by physical-mechanical properties but also by biochemical properties. In the present review, the applicability of natural plant fibers as oriented distributed fiber-reinforced soil (ODFS) and randomly distributed fiber-reinforced soil (RDFS) are extensively discussed and emphasized the inspiration of RDFS based on the emerging trend. Review also attempts to explore the importance of biochemical composition of natural-fibers on the performance in subsoil reinforced conditions. The treatment methods which enhances the behavior and lifetime of fibers, are also presented. While outlining the current potential of fiber reinforcement technology, some key research gaps have been highlighted at their importance. Finally, the review briefly documents the future direction of the fiber reinforcement technology by associating bio-mediated technological line.

Roles of Microbial Activity and Anthraquinone-2,7-disulfonate as a Model of Humic Substances in Leaching of Iron from Hematite into Seawater
Apichaya Aneksampant, Atsushi Tanaka, Xuefei Tu, Hisanori Iwai, Mitsuo Yamamoto, Kazunori Nakashima, Masami Fukushima
Analytical Sciences, 2018年, ［査読有り］
英語, 研究論文（学術雑誌）

Effects of Various Factors on Carbonate Particle Growth Using Ureolytic Bacteria
Md. Al Imran, Mai Shinmura, Kazunori Nakashima, Satoru Kawasaki
Materials Transactions, 59, 9, 1520, 1527, 2018年, ［査読有り］
英語, 学位論文（その他）

Effects of cationic polypeptide on CaCO3 crystallization and sand solidification by microbial-induced carbonate precipitation
Thiloththama H, K. Nawarathna, Kazunori Nakashima, Masahiro Fujita, Momoko Takatsu, Satoru Kawasaki
ACS Sustainable Chemistry & Engineering, 6, 10315, 10322, 2018年, ［査読有り］
英語

Soil improvement using plant-derived urease-induced Calcium Carbonate precipitation
R. A. N. Dilrukshi, Kazunori Nakashima, Satoru Kawasaki
Soils and Foundations, 58, 894, 910, 2018年, ［査読有り］
英語, 研究論文（学術雑誌）

Enhancement of microbially induced carbonate precipitation using organic biopolymer
Thiloththama Hiranya Kumari Nawarathna, Kazunori Nakashima, Satoru Kawasaki
International Journal of GEOMATE, 14, 41, 7, 12, GEOMATE International Society, 2018年, ［査読有り］
英語, 研究論文（学術雑誌）, Microbially induced carbonate precipitation (MICP) by using ureolytic bacteria is a novel and environmentally friendly way to treat the un-cemented sand. It was implemented successfully in number of geotechnical applications. Use of organic additives to improve the MICP process is a novel and interesting approach. In this research, effect of the cationic biopolymer poly-l-lysine on the MICP process was investigated by using ureolytic bacteria Pararhodobacter sp. Urea hydrolysis by the bacteria in the presence of CaCl2 was conducted with the addition of the polymer under different conditions. Morphology of the precipitate of CaCO3 after oven dried was analyzed by using the scanning electron microscope. Bell-shaped curve was obtained for the variation between the amount of the precipitate with the increase of the amount of the poly-l-lysine. Poly-L-lysine gives higher amount of precipitate than conventional MICP process and morphology of the crystals changed drastically from well-developed rhombohedral crystals to ellipsoidal shaped aggregates.

Electricity generation from rice bran by a microbial fuel cell and the influence of hydrodynamic cavitation pretreatment
Yuta Yoshimura, Kazunori Nakashima, Masaji Kato, Kengo Inoue, Fumiyoshi Okazaki, Hitoshi Soyama, Satoru Kawasaki
ACS Omega, 3, 11, 15267, 15271, AMER CHEMICAL SOC, 2018年, ［査読有り］
英語, 研究論文（学術雑誌）, Single-chamber microbial fuel cells (MFCs) were constructed using rice bran (carbon source) and pond bottom mud (microbial source). The total electric charge obtained in the MFC combining rice bran with pond bottom mud was four times higher than that in MFC using only rice bran. Phylogenetic analyses revealed dominant growth of fermentative bacteria such as Bacteroides and Clostridium species, and exoelectrogenic Geobacter species in the anode biofilms, suggesting that mutualism of these bacteria is a key factor for effective electricity generation in the MFC. Furthermore, rice bran, consisting of persistent polysaccharide, was pretreated by the hydrodynamic cavitation system to improve the digestibility and enhance the efficiency in MFC, resulting in 26% increase in the total production of electricity.

Bioremediation of lead-contaminated mine waste by Pararhodobacter sp based on the microbially induced calcium carbonate precipitation technique and its effects on strength of coarse and fine grained sand
Wilson Mwandira, Kazunori Nakashima, Satoru Kawasaki
ECOLOGICAL ENGINEERING, 109, A, 57, 64, ELSEVIER SCIENCE BV, 2017年12月, ［査読有り］
英語, 研究論文（学術雑誌）, Lead (Pb2+) is a toxic heavy metal that has a severe negative effect on human health and the environment. Physical, chemical and biological remediation techniques have long been used to remediate lead contamination. However, because of the great danger posed by lead contamination, there is increasing interest to apply ecofriendly and sustainable methods to remediate lead. Therefore, this study was conducted to use the microbially induced calcium carbonate precipitation (MICP) technique in conjunction with the bacterium Pararhodobacter sp. to bioremediate lead. Laboratory scale experiments were conducted and complete removal of 1036 mg/L of Pb2+ was achieved. These results were further confirmed by scanning electron microscope (SEM) and X-ray diffraction (XRD) analysis, which indicated coprecipitation of calcium carbonate (CaCO3) and lead. The unconfined compressive strength increased with an increase in injection interval with maximum unconfined compressive strength of 1.33 MPa for fine sand, 2.87 MPa for coarse sand and 2.80 MPa for mixed sand. For Pararhodobacter sp. to efficiently induce lead immobilisation the bacterial interval required is four times with a calcium and urea concentration of 0.5 M and bacterial concentration of 109 cfu/mL. Very few low-cost in situ heavy metal treatment processes for lead bioremediation are available; therefore, bioimmobilization of lead by MICP has the potential for application as a low-cost and eco-friendly method for heavy metal remediation.

Whole-cell evaluation of urease activity of Pararhodobacter sp isolated from peripheral beachrock
Masahiro Fujita, Kazunori Nakashima, Varenyam Achal, Satoru Kawasaki
BIOCHEMICAL ENGINEERING JOURNAL, 124, 1, 5, ELSEVIER SCIENCE BV, 2017年08月, ［査読有り］
英語, 研究論文（学術雑誌）, Pararhodobacter sp. SW is a urease-producing bacterium and can be used for microbial induced calcium carbonate precipitation (MICP). In the present study, microbial cells are directly used for the analysis of urease activity without extraction or purification of urease. The whole-cell evaluation of the bacteria provides important and comprehensive information on urease activity because the bacterial cells are directly used in biomineralization process. The urease activity of Pararhodobacter sp. increased with cell growth during cultivation and the bacteria maintained its enzyme activity even after 15-days culture. High urease activity was obtained at relatively high temperature around 60 degrees C and neutral pH around 8. It is revealed that urease was not secreted in culture medium but would accumulate in/on the cell, and resuspended cells obviously showed urease activity. Meanwhile, the enzyme activity was detected in a soluble fraction of cell lysate. Furthermore, clear band based on urease activity was observed in soluble fraction of cell lysate in native PAGE analysis followed by activity staining. These findings will contribute to the efficient biocementation using this ureolytic bacteria. (c) 2017 Elsevier B.V. All rights reserved.

Direct Ethanol Production from Ionic Liquid-Pretreated Lignocellulosic Biomass by Cellulase-Displaying Yeasts
Ryosuke Yamada, Kazunori Nakashima, Nanami Asai-Nakashima, Wataru Tokuhara, Nobuhiro Ishida, Satoshi Katahira, Noriho Kamiya, Chiaki Ogino, Akihiko Kondo
APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY, 182, 1, 229, 237, HUMANA PRESS INC, 2017年05月, ［査読有り］
英語, 研究論文（学術雑誌）, Among the many types of lignocellulosic biomass pretreatment methods, the use of ionic liquids (ILs) is regarded as one of the most promising strategies. In this study, the effects of four kinds of ILs for pretreatment of lignocellulosic biomass such as bagasse, eucalyptus, and cedar were evaluated. In direct ethanol fermentation from biomass incorporated with ILs by cellulase-displaying yeast, 1-butyl-3-methylimidazolium acetate ([Bmim][OAc]) was the most effective IL. The ethanol production and yield from [Bmim][OAc]-pretreated bagasse reached 0.81 g/L and 73.4% of the theoretical yield after fermentation for 96 h. The results prove the initial concept, in which the direct fermentation from lignocellulosic biomass effectively promoted by the pretreatment with IL.

Combination technology of geotextile tube and artificial beachrock for coastal protection
Md. Al Imran, Kazunori Nakashima, Satoru Kawasaki
International Journal of GEOMATE, 13, 39, 67, 72, GEOMATE International Society, 2017年, ［査読有り］
英語, 研究論文（学術雑誌）, In recent years, traditional forms of river and coastal structures have become very expensive to build and maintain, because of the shortage of natural rock. Therefore, the materials used in hydraulic and coastal structures are changing from traditional rubble and concrete systems to cheaper, sustainable, and eco-friendly materials and systems such as artificial rock, gabion, slags, geosynthetics, and so on. Moreover, shorelines are being continually eroded by the wave action of the sea, and the river and coastal structures are frequently damaged by both anthropogenic and natural causes such as over wash and storm. How to deal with eroding coastal problems is a main topic of this article. Recently, artificial beachrock and geotextile tube technology has changed from being an alternative construction technique and, in fact, has advanced to become the prime solution of choice. Therefore, the objectives of the present study is to find out the feasibility to protect coastal erosion in Asia along with using artificial beachrock and geotextile tube technology in a cheaper, sustainable and eco-friendly way.

Evaluation of porosity in biogrouted sand using microfocus X-ray CT
Shumpei Mitsuyama, Kazunori Nakashima, Satoru Kawasaki
International Journal of GEOMATE, 12, 31, 71, 76, GEOMATE International Society, 2017年, ［査読有り］
英語, 研究論文（学術雑誌）, Biogrouting is a method employed for ground improvement based on microbially induced calcium carbonate precipitation. It is commonly believed that biogrout has environmental and economic benefits. However, there remains the need to clearly understand the internal structure of biogrouted soil. In this study, we use microfocus X-ray computed tomography (CT) to evaluate the porosity in biogrouted sand. X-ray CT is useful as a non-distractive inspection tool. First, we prepare small specimens using coral sand at different dilution rates of culture solution. After carrying out a solidification test for 2 wks., we perform an unconfined compressive strength (UCS) test and measure the porosity of the specimens. Our aim is to investigate the influence of the dilution rate on the UCS and the porosity of sand specimens. The results show that a lower dilution rate resulted in a lower sand-specimen porosity and an increase in the UCS. We investigate the precipitation that fills a void. Then, we investigate the relationship between UCS and the ratio of porosity. There was a negative correlation between UCS and porosity, which closely agrees with previous research. We confirm the validity of the result, and we determine the UCS from the porosity.

Effectiveness of Adjustable-Volume Packed-Bed Reactor with an Ion-Exchange Resin Catalyst for Continuous Production
Kota Yamazaki, Naomi Shibasaki-Kitakawa, Kazunori Nakashima, Toshikuni Yonemoto
JOURNAL OF CHEMICAL ENGINEERING OF JAPAN, 49, 7, 668, 672, SOC CHEMICAL ENG JAPAN, 2016年07月, ［査読有り］
英語, 研究論文（学術雑誌）, Packed-bed reactors filled with ion-exchange resin catalysts are very effective for the continuous production of various chemicals. However, the resin tends to swell or shrink depending on the composition of the surrounding solution, and this can greatly alter the resin bed height and the volume of the liquid phase above the resin in a fixed-volume reactor. Because this liquid phase does not contribute to the production of chemicals in the reaction, it is important to minimize the liquid-phase volume to increase the productivity. In the present study, an adjustable-volume packed-bed reactor system was developed, and its effectiveness for the continuous production of fatty acid esters and regeneration of the resin were evaluated. The column height was adjusted by controlling the position of a movable plunger to minimize the liquid-phase volume in the upper part of the column. In fatty acid ester production using the adjustable-volume reactor, the residence time of the reactants in the liquid phase was shorter than that in a fixed-volume reactor, and the solution was rapidly eluted from the column, which improved productivity. For resin regeneration, minimization of the liquid-phase volume in the adjustable-volume reactor reduced the effect of dilution on the performance of the regeneration solutions compared to that in the fixed-volume reactor, and less regeneration solution was required. The adjustable-volume reactor could allow for more efficient and environment-friendly production of chemicals than a fixed-volume reactor.

Pretreatment combining ultrasound and sodium percarbonate under mild conditions for efficient degradation of corn stover
Kazunori Nakashima, Yuuki Ebi, Masaki Kubo, Naomi Shibasaki-Kitakawa, Toshikuni Yonemoto
ULTRASONICS SONOCHEMISTRY, 29, 455, 460, ELSEVIER SCIENCE BV, 2016年03月, ［査読有り］
英語, 研究論文（学術雑誌）, Ultrasound (US) can be used to disrupt microcrystalline cellulose to give nanofibers via ultrasonic cavitation. Sodium percarbonate (SP), consisting of sodium carbonate and hydrogen peroxide, generates highly reactive radicals, which cause oxidative delignification. Here, we describe a novel pretreatment technique using a combination of US and SP (US-SP) for the efficient saccharification of cellulose and hemicellulose in lignocellulosic corn stover. Although US-SP pretreatment was conducted under mild condition (i.e., at room temperature and atmospheric pressure), the pretreatment greatly increased lignin removal and cellulose digestibility. We also determined the optimum US-SP treatment conditions, such as ultrasonic power output, pretreatment time, pretreatment temperature, and SP concentration for an efficient cellulose saccharification. Moreover, xylose could be effectively recovered from US-SP pre-treated biomass without the formation of microbial inhibitor furfural. (C) 2015 Elsevier B.V. All rights reserved.

Novel simple process for tocopherols selective recovery from vegetable oils by adsorption and desorption with an anion-exchange resin
Kousuke Hiromori, Naomi Shibasaki-Kitakawa, Kazunori Nakashima, Toshikuni Yonemoto
FOOD CHEMISTRY, 194, 1, 5, ELSEVIER SCI LTD, 2016年03月, ［査読有り］
英語, 研究論文（学術雑誌）, A novel and simple low-temperature process was used to recover tocopherols from a deodorizer distillate, which is a by-product of edible oil refining. The process consists of three operations: the esterification of free fatty acids with a cation-exchange resin catalyst, the adsorption of tocopherols onto an anion-exchange resin, and tocopherol desorption from the resin. No degradation of tocopherols occurred during these processes. In the tocopherol-rich fraction, no impurities such as sterols or glycerides were present. These impurities are commonly found in the product of the conventional process. This novel process improves the overall recovery ratio and the mass fraction of the product (75.9% and 51.0 wt%) compared with those in the conventional process (50% and 35 wt%). (C) 2015 Elsevier Ltd. All rights reserved.

Hydrodynamic Cavitation Reactor for Efficient Pretreatment of Lignocellulosic Biomass
Kazunori Nakashima, Yuuki Ebi, Naomi Shibasaki-Kitakawa, Hitoshi Soyama, Toshikuni Yonemoto
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH, 55, 7, 1866, 1871, AMER CHEMICAL SOC, 2016年02月, ［査読有り］
英語, 研究論文（学術雑誌）, In the present study, hydrodynamic (HD) cavitation was combined with sodium percarbonate (SP) for the pretreatment of lignocellulosic biomass. For HD cavitation, a circular flow system equipped with a venturi tube was employed. The combined system of HD and SP (HD-SP) was compared to a pretreatment system using ultrasonication and SP (US-SP). The efficacy of each pretreatment method was evaluated by measuring lignin removal, and glucose and xylose formation. Fourier transform infrared spectra indicated that both systems resulted in a similar degree of lignin removal; however, the HD-SP system was more efficient than the US-SP system for glucose and xylose production. Neither system generated the inhibitor furfural, while it was detected in dilute acid (DA)-pretreated biomass. Furthermore, changing the venturi tube throat diameter improved the efficacy of the HD-SP system. The HD-SP system is promising for the industrial pretreatment of lignocellulosic biomass.

Production of high quality biodiesel from waste acid oil obtained during edible oil refining using ion-exchange resin catalysts
Naomi Shibasaki-Kitakawa, Kousuke Hiromori, Toru Ihara, Kazunori Nakashima, Toshikuni Yonemoto
FUEL, 139, 11, 17, ELSEVIER SCI LTD, 2015年01月
英語, 研究論文（学術雑誌）, This study was aimed at the continuous production of high quality biodiesel fuel, which fully satisfies international specifications, from waste acid oil with free fatty acids (FFA) content of > 95 wt%. First, the effect of water on the esterification of FFA with the cation-exchange resin catalyst was discussed. Then, a simple method for pretreating the resin without drying, only supplying alcohol of 1.5 cm(3)/g (wet resin), was proposed. Second, the operating conditions for the continuous esterification of FFA to biodiesel were established. The complete conversion of FFA was achieved at the mole ratio of alcohol: fatty acid residue of 2:1 and sufficient residence time. Subsequent processing with an anionexchange resin catalyst for the transesterification of triglycerides in the oil was necessary to produce high quality biodiesel. The biodiesel productivity with acid oil was about 8.5 times higher than that with triglyceride-rich oil. This process demonstrated a commercially feasible route to high quality biodiesel. (C) 2014 Elsevier Ltd. All rights reserved.

Improvement of enzymatic activity of β-glucosidase from Thermotoga maritima by 1-butyl-3-methylimidazolium acetate
Motonori Kudou, Yuka Kubota, Nanami Nakashima, Fumiyoshi Okazaki, Kazunori Nakashima, Chiaki Ogino, Akihiko Kondo
Journal of Molecular Catalysis B: Enzymatic, 104, 17, 22, ELSEVIER SCIENCE BV, 2014年06月
英語, 研究論文（学術雑誌）, The uses of ionic liquids (ILs) to alter the performance of enzymes and to pretreat cellulosic biomass have been investigated. In the present study, the activity of beta-glucosidase from Themotoga maritime (TmBgl1A) was studied in a phosphate buffer containing imidazolium-based ILs. Among the imidazolium-based ILs that were tested, 1-butyl-3-methylimidazolium acetate [Bmim][OAc] showed the most improvement for the hydrolysis activity of TmBgl1A at pH 7.0. From the steady-state emission spectra, [Bmim][OAc] quenched the intrinsic fluorescence of TmBgl1A. The improvement in the activity of TmBgl1A induced by [Bmim][OAc] could be linked to the flexibility of the conformation of TmBgl1A. (C) 2014 Elsevier B.V. All rights reserved.

A fusion enzyme consisting of bacterial expansin and endoglucanase for the degradation of highly crystalline cellulose
Kazunori Nakashima, Koji Endo, Naomi Shibasaki-Kitakawa, Toshikuni Yonemoto
RSC ADVANCES, 4, 83, 43815, 43820, ROYAL SOC CHEMISTRY, 2014年
英語, 研究論文（学術雑誌）, We have prepared novel fusion enzymes consisting of Bacillus subtilis expansin EXLX1 and Clostridium thermocellum endoglucanase CelD. These two components are directly fused, or fused using flexible glycine-serine peptide linkers (GGGGS, GS linker) with different lengths: a triplicate (GGGGS) 3 linker (GS3) and a sextuple (GGGGS)(6) linker (GS6), resulting in fusion enzymes EXLX1-CelD, EXLX1-GS3-CelD and EXLX1-GS6-CelD. The binding ability and digestibility of these fusion enzymes towards a series of cellulose substrates with different crystallinity index (CrI) was examined. Fused with EXLX1, CelD acquired high binding ability to various kinds of cellulose and the linkaer length had no impact on function. In the degradation of cellulose, EXLX1-GS3-CelD exhibited the highest degradation activity among the fusion enzymes examined, suggesting that linker length between the two proteins has a significant impact on the activity of the fusion enzyme. EXLX1-GS3-CelD was found to function more effectively towards higher crystalline celluloses.

Thermal Stability and Starch Degradation Profile of α-Amylase from Streptomyces avermitilis
Sang Youn Hwang, Kazunori Nakashima, Naoko Okai, Fumiyoshi Okazaki, Michiru Miyake, Koichi Harazono, Chiaki Ogino, Akihiko Kondo
Bioscience, Biotechnology, and Biochemistry, 77, 12, 2449, 2453, TAYLOR & FRANCIS LTD, 2013年12月
英語, 研究論文（学術雑誌）, Amylases from Streptontyces are useful in the production of maltooligosaccharides, but they have weak thermal stability at temperatures higher than 40 degrees C. In this study, alpha-amylase (SAV5981 gene of Streptomyces avermitilis) was expressed from Streptomyces lividans 1326 and purified by ammonium sulfate fractionation followed by anionic chromatography (Q-HP sepharose). The properties of the purified SAV5981 amylase were determined by the starch-iodine method. The effect of metal ions on amylase activity was investigated. The optimal temperature shifted from 25 to 50 degrees C with the addition of the Ca2+ ion. The thermal stability of SAV5981 was also dramatically enhanced by the addition of 10 mm CaCl2. Improvement of the thermal stability of SAV5981 was examined by CD spectra in the presence and the absence of the Ca2+ ion. Thin-layer chromatography (TLC) analysis and HPLC analysis of starch degradation revealed that SAV5981 mainly produced maltose and maltotriose, not glucose. The maltoorigosaccharide-producing amylase examined in this study has the potential in the industrial application of oligosaccharide production.

Simultaneous production of high quality biodiesel and glycerin from Jatropha oil using ion-exchange resins as catalysts and adsorbent
Naomi Shibasaki-Kitakawa, Keiichi Kanagawa, Kazunori Nakashima, Toshikuni Yonemoto
BIORESOURCE TECHNOLOGY, 142, 732, 736, ELSEVIER SCI LTD, 2013年08月
英語, 研究論文（学術雑誌）, The simultaneous production of high quality biodiesel and glycerin was realized by a bench-scale process using expanded-bed reactors packed with cation- and anion-exchange resins. The mixed-solution of crude Jatropha oil and methanol at a stoichiometric molar ratio was supplied to the process. The free fatty acid as well as triglyceride was completely converted to biodiesel. All by-products were adsorbed on the resin and the effluent from the process was free from them. The effluent fully met the international biodiesel standard specifications without any downstream purification processes except for removing methanol. The glycerin adsorbed on the resin was completely recovered as a transparent methanol solution during regeneration of the resin. (C) 2013 Elsevier Ltd. All rights reserved.

Production of human secreted alkaline phosphatase in suspension and immobilization cultures of tobacco NT1 cell
Kazunori Nakashima, Naomi Shibasaki-Kitakawa, Takuya Miyamoto, Masaki Kubo, Toshikuni Yonemoto, Michael L. Shuler
BIOCHEMICAL ENGINEERING JOURNAL, 77, 177, 182, ELSEVIER SCIENCE SA, 2013年08月
英語, 研究論文（学術雑誌）, The recombinant protein production by a plant cell culture offers several advantages including product safety and ease of the purification of secreted proteins and the capability of plants to correctly fold complex proteins. However, low productivity is generally a limitation of this system, caused by the denaturation and degradation of the secreted proteins due to proteolytic enzyme protease in the medium. In this study, we demonstrated that the transgenic tobacco NT1 cells were immobilized in Ca2+-alginate gel beads coated with a cell-free gel film, which significantly improved the productivity of the recombinant human secreted alkaline phosphatase (SEAP), about 33 times larger than that in the suspension culture. The cells immobilized in the beads were protected from hydrodynamic stress during cultivation and hence did not release the endogenous protease, which caused damage to the secreted SEAP. The immobilization culture without cell leakage could be quite effective for the production of recombinant protein. (C) 2013 Elsevier B.V. All rights reserved.

Production of biodiesel from plant oil hydrolysates using an Aspergillus oryzae whole-cell biocatalyst highly expressing Candida antarctica lipase B
Daisuke Adachi, Shinji Hama, Kazunori Nakashima, Takayuki Bogaki, Chiaki Ogino, Akihiko Kondo
BIORESOURCE TECHNOLOGY, 135, 410, 416, ELSEVIER SCI LTD, 2013年05月
英語, 研究論文（学術雑誌）, For enzymatic biodiesel production from plant oil hydrolysates, an Aspergillus oryzae whole-cell biocatalyst that expresses Candida antarctica lipase B (r-CALB) with high esterification activity was developed. Each of soybean and palm oils was hydrolyzed using Candida rugosa lipase, and the resultant hydrolysates were subjected to esterification where immobilized r-CALB was used as a catalyst. In esterification, r-CALB afforded a methyl ester content of more than 90% after 6 h with the addition of 1.5 M equivalents of methanol. Favorably, stepwise additions of methanol and a little water were unnecessary for maintaining the lipase stability of r-CALB during esterification. During long-term esterification in a rotator, r-CALB can be recycled for 20 cycles without a significant loss of lipase activity, resulting in a methyl ester content of more than 90% even after the 20th batch. Therefore, the presented reaction system using r-CALB shows promise for biodiesel production from plant oil hydrolysates. (C) 2012 Elsevier Ltd. All rights reserved.

An integrative process model of enzymatic biodiesel production through ethanol fermentation of brown rice followed by lipase-catalyzed ethanolysis in a water-containing system
Daisuke Adachi, Risa Koda, Shinji Hama, Ryosuke Yamada, Kazunori Nakashima, Chiaki Ogino, Akihiko Kondo
ENZYME AND MICROBIAL TECHNOLOGY, 52, 2, 118, 122, ELSEVIER SCIENCE INC, 2013年02月
英語, 研究論文（学術雑誌）, We attempted to integrate lipase-catalyzed ethanolysis into fermentative bioethanol production. To produce bioethanol, ethanol fermentation from brown rice was conducted using a tetraploid Saccharomyces cerevisiae expressing alpha-amylase and glucoamylase. The resultant ethanol was distilled and separated into three fractions with different concentrations of water and fusel alcohols. In ethanolysis using the first fraction with 89.3% ethanol, a recombinant Aspergillus oryzae whole-cell biocatalyst expressing Fusarium heterosporum lipase (r-FHL) afforded the highest ethyl ester content of 94.0% after 96 h. Owing to a high concentration of water in the bioethanol solutions, r-FHL, which works best in the presence of water when processing ethanolysis, was found to be more suitable for the integrative process than a commercial immobilized Candida antarctica lipase. In addition, r-FHL was used for repeated-batch ethanolysis, resulting in an ethyl ester content of more than 80% even after the fifth batch. Fusel alcohols such as 1-butanol and isobutyl alcohol are thought to decrease the lipase activity of r-FHL. Using this process, a high ethyl ester content was obtained by simply mixing bioethanol, plant oil, and lipase with an appropriate adjustment of water concentration. The developed process model, therefore, would contribute to biodiesel production from only biomass-derived feedstocks. (c) 2012 Elsevier Inc. All rights reserved.

Versatile Supramolecular Gelators That Can Harden Water, Organic Solvents and Ionic Liquids
Nami Minakuchi, Kazuki Hoe, Daisuke Yamaki, Seiichiro Ten-no, Kazunori Nakashima, Masahiro Goto, Minoru Mizuhata, Tatsuo Maruyama
LANGMUIR, 28, 25, 9259, 9266, AMER CHEMICAL SOC, 2012年06月
英語, 研究論文（学術雑誌）, \We developed novel supramolecular gelators with simple molecular structures that could harden a broad range of solvents: aqueous solutions of a wide pH range, organic solvents, edible oil, biodiesel, and ionic liquids at gelation concentrations of 0.1-2 wt %. The supramolecular gelators were composed of a long hydrophobic tail, amino acids and gluconic acid, which were prepared by liquid-phase synthesis. Among seven types of the gelators synthesized, the gelators containing L-Val, L-Leu, and L-Ile exhibited high gelation ability to various solvents. These gelators were soluble in aqueous and organic solvents, and also in ionic liquids at high temperature. The gelation of these solvents was thermally reversible. The microscopic observations (TEM, SEM, and CLSM) and small-angle X-ray scattering (SAXS) measurements suggested that the gelator molecules self-assembled to form entangled nanofibers in a large variety of solvents, resulting in the gelation of these solvents. Molecular mechanics and density functional theory (DFT) calculations indicated the possible molecular packing of the gelator in the nanofibers. Interestingly, the gelation of an ionic liquid by our gelator did not affect the ionic conductivity of the ionic liquid, which would provide an advantage to electrochemical applications.

Short time ionic liquids pretreatment on lignocellulosic biomass to enhance enzymatic saccharification
Uju, Yasuhiro Shoda, Aya Nakamoto, Masahiro Goto, Wataru Tokuhara, Yoshiyuki Noritake, Satoshi Katahira, Nobuhiro Ishida, Kazunori Nakashima, Chiaki Ogino, Noriho Kamiya
BIORESOURCE TECHNOLOGY, 103, 1, 446, 452, ELSEVIER SCI LTD, 2012年01月
英語, 研究論文（学術雑誌）, The potential of 1-buthyl-3-methylpyridinium chloride, [Bmpy][Cl], as a pretreatment solvent for lignocellulosic biomasses, Bagasse and Eucalyptus, was investigated. The yields of regenerated biomasses ranged between 35% and 96%, and varied according to the pretreatment time, type of ionic liquid (IL) and biomass. The pretreatment of the biomass with [Bmpy][Cl] resulted in up to 8-fold increase in the cellulose conversion when compared with the untreated biomass. For a short pretreatment period (i.e., 10 min), [Bmpy][Cl] showed better performance than 1-ethyl-3-methylimidazolium acetate ([Emim][OAc]) with respect to the initial enzymatic saccharification rates. The increase in the reaction rates with [Emim][OAc] treatment was because of a reduction in the cellulose crystallinity. In contrast, a decrease in the crystallinity index was not clearly observed for the biomass pretreated with [Bmpy][Cl], and the enhancement of the enzymatic saccharification rates using this IL is presumably due to a reduction in the degree of polymerization of cellulose in the biomass. (C) 2011 Published by Elsevier Ltd.

Development of an Aspergillus oryzae whole-cell biocatalyst coexpressing triglyceride and partial glyceride lipases for biodiesel production
Daisuke Adachi, Shinji Hama, Takao Numata, Kazunori Nakashima, Chiaki Ogino, Hideki Fukuda, Akihiko Kondo
BIORESOURCE TECHNOLOGY, 102, 12, 6723, 6729, ELSEVIER SCI LTD, 2011年06月
英語, 研究論文（学術雑誌）, An Aspergillus oryzae whole-cell biocatalyst which coexpresses Fusarium heterosporum lipase (FHL) and mono- and di-acylglycerol lipase B (mdlB) in the same cell has been developed to improve biodiesel production. By screening a number of transformants, the best strain was obtained when FHL gene was integrated into A. oryzae chromosome using (S)C selection marker while mdlB was integrated using niaD selection marker. The reaction system using the lipase-coexpressing whole-cells was found to be superior in biodiesel production to others such as lipase-mixing and two-step reactions, affording the highest reaction rate and the highest ME content (98%). Moreover, an ME content of more than 90% was maintained during 10 repeated batch cycles. The whole-cell biocatalyst developed in this work would be promising biocatalysts for efficient biodiesel production. (C) 2011 Elsevier Ltd. All rights reserved.

Highly efficient biodiesel production by a whole-cell biocatalyst employing a system with high lipase expression in Aspergillus oryzae
Tomohiro Takaya, Risa Koda, Daisuke Adachi, Kazunori Nakashima, Junpei Wada, Takayuki Bogaki, Chiaki Ogino, Akihiko Kondo
APPLIED MICROBIOLOGY AND BIOTECHNOLOGY, 90, 3, 1171, 1177, SPRINGER, 2011年05月
英語, 研究論文（学術雑誌）, In the present study, a system with high lipase expression in Aspergillus oryzae was developed using an improved enolase promoter (P-enoA124) and the 5' , methanolysiuntranslated region of a heat-shock protein (Hsp-UTR). P-enoA142 enhanced the transcriptional level of a heterologous lipase gene and Hsp-UTR improved its translational efficiency. Fusarium heterosporum lipase (FHL) was inserted into a pSENSU-FHL expression vector harboring P-enoA142 and Hsp-UTR and was transformed into an A. oryzae NS4 strain. Transformants possessing pSENSU-FHL in single (pSENSU-FHL#1) and double copies (pSENSU-FHL#2) were selected to evaluate the lipase activity of the whole-cell biocatalyst. The two strains, pSENSU-FHL#1 and #2, showed excellent lipase activity in hydrolysis compared with the strain transformed with conventional expression vector pNAN8142-FHL. Furthermore, by using pSENSU-FHL#2s could proceed much more effectively without deactivation, which allowed a swift addition of methanol to the reaction mixture, thereby reducing reaction time.

Water activity dependence of performance of surface-displayed lipase in yeast cells: A unique water requirement for enzymatic synthetic reaction in organic media
Ayumi Yoshida, Shinji Hama, Kazunori Nakashima, Akihiko Kondo
ENZYME AND MICROBIAL TECHNOLOGY, 48, 4-5, 334, 338, ELSEVIER SCIENCE INC, 2011年04月
英語, 研究論文（学術雑誌）, Water activity (a(w)) is a crucial parameter affecting enzymatic synthetic reactions in organic media. In this paper, we report on the a(w) dependence of surface-displayed lipases, genetically immobilized on yeast cells via fusion with cell wall proteins. When Saccharomyces cerevisiae displaying Rhizopus oryzae lipase was used for esterification in n-hexane, equilibrating the dried cells with water prior to the reaction markedly increased the reaction rate. An equilibration of the cells with various saturated salt solutions showed that the reaction rate increased with increasing a(w) of the salt solution, to give the best performance at a(w) of 1.0. Interestingly, this trend was extremely different from those of lipases in powder or resin-immobilized form. To determine whether the cell surface is responsible for the unique a(w) profiles, an investigation was carried out similarly using other lipase sources and yeast strains, which indicated that, in all the cells examined, a higher a(w) resulted in a higher reaction rate. Moreover, increasing a(w) was found to increase the cell surface hydrophobicity determined by an aqueous-hydrocarbon biphasic partitioning assay. These results indicate that lipases displayed on yeast cells show a unique a(w) dependence probably because of the variation in cell surface characteristics. (C) 2011 Elsevier Inc. All rights reserved.

Direct bioethanol production from cellulose by the combination of cellulase-displaying yeast and ionic liquid pretreatment
Kazunori Nakashima, Koji Yamaguchi, Naho Taniguchi, Shogo Arai, Ryosuke Yamada, Satoshi Katahira, Nobuhiro Ishida, Haruo Takahashi, Chiaki Ogino, Akihiko Kondo
GREEN CHEMISTRY, 13, 10, 2948, 2953, ROYAL SOC CHEMISTRY, 2011年
英語, 研究論文（学術雑誌）, The efficient production of biofuels from cellulosic biomass is a current imperative. The present study demonstrates direct bioethanol production from cellulose by cellulase-displaying yeast (arming yeast) using ionic liquid pretreatment. In this approach, all of the bioethanol production processes (pretreatment, saccharification, and fermentation) were conducted in a single vessel. In a preliminary test, the arming yeast showed resistance to cellulose-dissolving ionic liquids below a concentration of approximately 200 mM. Cellulose degradation and ethanol productivity by the arming yeast was dramatically enhanced by pretreatment with ionic liquids. The addition of free cellulases during fermentation significantly enhanced ethanol productivity in the arming yeast system, producing approximately 90% ethanol yield. Furthermore, in a preliminary examination, 82% of the ionic liquids in the culture medium could be recovered and recycled for the pretreatment of cellulose.

Ethanolysis of rapeseed oil to produce biodiesel fuel catalyzed by Fusarium heterosporum lipase-expressing fungus immobilized whole-cell biocatalysts
Risa Koda, Takao Numata, Shinji Hama, Sriappareddy Tamalampudi, Kazunori Nakashima, Tsutomu Tanaka, Chiaki Ogino, Hideki Fukuda, Akihiko Kondo
JOURNAL OF MOLECULAR CATALYSIS B-ENZYMATIC, 66, 1-2, 101, 104, ELSEVIER SCIENCE BV, 2010年09月
英語, 研究論文（学術雑誌）, We demonstrated ethanolysis of rapeseed oil to produce biodiesel fuel using lipase-producing filamentous fungi immobilized on biomass support particles (BSPs) as a whole-cell biocatalyst. We prepared two types of whole-cell biocatalyst: wild-type Rhizopus oryzae producing triacylglycerol lipase (w-ROL) and recombinant Aspergillus oryzae expressing Fusarium heterosporum lipase (r-FHL). Both w-ROL and r-FHL successfully catalyzed the ethanolysis of rapeseed oil, and the fatty acid ethyl ester yield was as high as 79% (w-ROL) or 94% (r-FHL). In the case of r-FHL, the residual monoglycerides (MGs) and diglycerides (DGs) were no more than 0.73 and 0.18%, respectively. In addition, r-FHL could be recycled for the ethanolysis of rapeseed oil, retaining over 85% fatty acid ethyl ester yield by the fifth cycle. r-FHL was revealed to be a promising catalyst for biodiesel production using rapeseed oil and ethanol. (C) 2010 Elsevier B.V. All rights reserved.

Surfactant-modified yeast whole-cell biocatalyst displaying lipase on cell surface for enzymatic production of structured lipids in organic media
Shinji Hama, Ayumi Yoshida, Kazunori Nakashima, Hideo Noda, Hideki Fukuda, Akihiko Kondo
APPLIED MICROBIOLOGY AND BIOTECHNOLOGY, 87, 2, 537, 543, SPRINGER, 2010年06月
英語, 研究論文（学術雑誌）, The cell surface engineering system, in which functional proteins are genetically displayed on microbial cell surfaces, has recently become a powerful tool for applied biotechnology. Here, we report on the surfactant modification of surface-displayed lipase to improve its performance for enzymatic synthesis reactions. The lipase activities of the surfactant-modified yeast displaying Rhizopus oryzae lipase (ROL) were evaluated in both aqueous and nonaqueous systems. Despite the similar lipase activities of control and surfactant-modified cells in aqueous media, the treatment with nonionic surfactants increased the specific lipase activity of the ROL-displaying yeast in n-hexane. In particular, the Tween 20-modified cells increased the cell surface hydrophobicity significantly among a series of Tween surfactants tested, resulting in 8-30 times higher specific activity in organic solvents with relatively high log P values. The developed cells were successfully used for the enzymatic synthesis of phospholipids and fatty acid methyl esters in n-hexane, whereas the nontreated cells produced a significantly low yield. Our results thus indicate that surfactant modification of the cell surface can enhance the potential of the surface-displayed lipase for bioconversion.

Recent advances of enzymatic reactions in ionic liquids
Muhammad Moniruzzaman, Kazunori Nakashima, Noriho Kamiya, Masahiro Goto
BIOCHEMICAL ENGINEERING JOURNAL, 48, 3, 295, 314, ELSEVIER SCIENCE SA, 2010年02月
英語, The tremendous potential of room temperature ionic liquids as an alternative to environmentally harmful ordinary organic solvents is well recognized. Ionic liquids, having no measurable vapor pressure, are an interesting class of tunable and designer solvents, and they have been used extensively in a wide range of applications including enzymatic biotransformation. In fact, ionic liquids can be designed with different cation and anion combinations, which allow the possibility of tailoring reaction solvents with specific desired properties, and these unconventional solvent properties of ionic liquids provide the opportunity to carry out many important biocatalytic reactions that are impossible in traditional solvents. As compared to those observed in conventional organic solvents, the use of enzymes in ionic liquids has presented many advantages such as high conversion rates, high enantioselectivity, better enzyme stability, as well as better recoverability and recyclability. To date, a wide range of pronounced approaches have been taken to further improve the performance of enzymes in ionic liquids. This review presents the recent technological developments in which the advantages of ionic liquids as a medium for enzymes have been gradually realized. (C) 2009 Elsevier B.V. All rights reserved.

Proteinase-mediated drastic morphological change of peptide-amphiphile to induce supramolecular hydrogelation
Daisuke Koda, Tatsuo Maruyama, Nami Minakuchi, Kazunori Nakashima, Masahiro Goto
CHEMICAL COMMUNICATIONS, 46, 6, 979, 981, ROYAL SOC CHEMISTRY, 2010年
英語, 研究論文（学術雑誌）, We report a novel peptide-amphiphile having a simple molecular structure that can gelate an aqueous solution at a remarkably low concentration and can be designed to be responsive to a disease-related enzyme by undergoing a drastic morphological change.

Production of biodiesel fuel from soybean oil catalyzed by fungus whole-cell biocatalysts in ionic liquids
Shogo Arai, Kazunori Nakashima, Takanori Tanino, Chiaki Ogino, Akihiko Kondo, Hideki Fukuda
ENZYME AND MICROBIAL TECHNOLOGY, 46, 1, 51, 55, ELSEVIER SCIENCE INC, 2010年01月
英語, 研究論文（学術雑誌）, The methanolysis of soybean oil to produce a fatty acid methyl ester (ME, i.e., biodiesel fuel) was catalyzed by lipase-producing filamentous fungi immobilized on biomass support particles (BSPs) as a whole-cell biocatalyst in the presence of ionic liquids. We used four types of whole-cell biocatalysts: wildtype Rhizopus oryzae producing triacylglycerol lipase (w-ROL), recombinant Aspergillus oryzae expressing Fusarium heterosporum lipase (r-FHL), Candida antarctica lipase B (r-CALB), and mono- and diacylglycerol lipase from A. oryzae (r-mdlB). w-ROL gave the high yield of fatty acid methyl ester (ME) in ionic liquid [Emim][BF(4)] or [Bmim][BF(4)] biphasic systems following a 24h reaction. While lipases are known to be severely deactivated by an excess amount of methanol (e.g. 1.5 Mequiv. of methanol against oil) in a conventional system, methanolysis successfully proceeded even with a methanol/oil ratio of 4 in the ionic liquid biphasic system, where the ionic liquids would work as a reservoir of methanol to suppress the enzyme deactivation. When only w-ROL was used as a biocatalyst for methanolysis, unreacted monoglyceride remained due to the 1,3-positional specificity of R. oryzae lipase. High ME conversion was attained by the combined use of two types of whole-cell biocatalysts, w-ROL and r-mdlB. In a stability test, the activity of w-ROL was reduced to one-third of its original value after incubation in [Bmim][BF(4)] for 72 h. The stability of w-ROL in [Bmim][BF(4)] was greatly enhanced by cross-linking the biocatalyst with glutaraldehyde. The present Study demonstrated that ionic liquids are promising candidates for use as the second solvent in biodiesel fuel production by whole-cell biocatalysts. (C) 2009 Elsevier Inc. All rights reserved.

Enzyme encapsulation in microparticles composed of polymerized ionic liquids for highly active and reusable biocatalysts
Kazunori Nakashima, Noriho Kamiya, Daisuke Koda, Tatsuo Maruyama, Masahiro Goto
ORGANIC & BIOMOLECULAR CHEMISTRY, 7, 11, 2353, 2358, ROYAL SOC CHEMISTRY, 2009年
英語, 研究論文（学術雑誌）, Horseradish peroxidase (HRP) is encapsulated in polymerized ionic liquid microparticles (pIL-MP), which are prepared by polymerization of 1-vinyl-3-ethylimidazolium bromide in the presence of the crosslinker N,N'-methylenebis(acrylamide) in a concentrated water-in-oil (W/O) emulsion. pIL-MP encapsulating HRP chemically-modified with comb-shaped polyethylene glycol (PM(13)-HRP) exhibit excellent activity for guaiacol oxidation in an aqueous solution. The PM(13)-HRP in pIL-MP shows more than 2-fold higher activity than that of the enzyme encapsulated in a polyacrylamide microparticle. The catalytic activity declines with an increase in the crosslinker concentration of the pIL-MP, probably due to suppression of substrate diffusion. The activity of PM(13)-HRP in pIL-MP depends on the external environment of the gel (i.e. pH and temperature). The pIL-MP are easily recovered from the reaction mixture by centrifugation, which makes it possible to recycle the biocatalyst for repeated oxidation reactions.

Extraction Behavior of Indium with TOPO into Ionic Liquids
Fukiko Kubota, Yosuke Shimobori, Yusuke Koyanagi, Kazunori Nakashima, Kojiro Shimojo, Noriho Kamiya, Masahiro Goto
SOLVENT EXTRACTION RESEARCH AND DEVELOPMENT-JAPAN, 16, 151, 155, JAPAN ASSOC SOLVENT EXTRACTION, 2009年
英語, 研究論文（学術雑誌）, The extraction behavior of In3+ into ionic liquids, [C(n)Mim][T(f)2N], was investigated with trioctylphosphine oxide (TOPO) as the extractant and compared with that of a conventional organic solvent system. In the n-dodecane system, the extractability of In3+ increased with increasing hydrochloric acid concentration in the feed aqueous phase. On the contrary when using ionic liquids, In3+ was more extracted at lower concentrations of hydrochloric acid. The contrast between the two systems is probably due to the difference in their extraction mechanisms. Extraction and separation properties of In3+ from Sn4+ Fe3+ and Al3+ were also examined. Indium was quantitatively extracted into the ionic liquid phase and the separation efficiency from other metal ions, especially from Fe3+ was enhanced compared with that in the organic solvent system .

Metal Extraction from Water and Organic Solvents into Fluorous Solvents by Fluorinated beta-Diketone and Its Application to the Colorimetric Analysis of Metal Ions
Kazunori Nakashima, Tatsuo Maruyama, Fukiko Kubota, Masahiro Goto
ANALYTICAL SCIENCES, 25, 1, 77, 82, JAPAN SOC ANALYTICAL CHEMISTRY, 2009年01月
英語, 研究論文（学術雑誌）, A metal extraction system using fluorous solvents has been developed. Perfluorinated beta-diketone, 1,1,1,5,5,6,6,6-octafluoro-2,4-hexanedione (C(6)F(8)beta DK) dissolves in the fluorous solvent FC-72 and can extract transition metal ions from water into FC-72. The extraction efficiency in the FC-72 system is comparable to that of chloroform. By using the immiscibility of FC-72 with conventional organic solvents, metal extraction was also achieved from acetonitrile and dioxane. Metal ions extracted into FC-72 can be readily stripped using 1 M nitric acid. We succeeded in a colorimetric assay of metal ion concentration in water and in organic solvents by contacting each solvent with FC-72 containing C(6)F(8)beta DK. Iron ions with different concentrations (0 - 0.1 mM) in water or acetonitrile are completely extracted into FC-72 to form a Fe(3+)-C(6)F(8)beta DK complex, which can be detected by spectrophotometry due to its absorption in the UV-vis re-ion. We have demonstrated that fluorous Solvents would be promising candidates for a novel separation and analytical medium for metal ions.

Enzymatic in situ saccharification of cellulose in aqueous-ionic liquid media
Noriho Kamiya, Yuichi Matsushita, Misa Hanaki, Kazunori Nakashima, Mamiko Narita, Masahiro Goto, Haruo Takahashi
BIOTECHNOLOGY LETTERS, 30, 6, 1037, 1040, SPRINGER, 2008年06月
英語, 研究論文（学術雑誌）, The enzymatic saccharification of a model cellulosic substrate, Avicel PH- 101, using an ionic liquid ( IL), 1- ethyl- 3- methylimidazolium diethylphosphate, was explored. After mixing the IL solution of cellulose with different volumes of 10 mM citrate buffer ( pH 5.0), cellulase was directly added to the aqueous- IL mixture at 40 degrees C. When the volume of IL to water was greater than 3: 2, little cellulase activity was observed. However, decreasing the volume ratio markedly enhanced enzymatic activity: an IL to water ratio of 1: 4 ( v/ v) resulted in over 70% of the starting amount of cellulose ( 10 mg/ ml) being converted to glucose and cellobiose.

Formation of reverse micelles in a room-temperature ionic liquid
Muhammad Moniruzzaman, Kamiya Noriho, Kazunori Nakashima, Masahiro Goto
CHEMPHYSCHEM, 9, 5, 689, 692, WILEY-BLACKWELL, 2008年04月
英語, 研究論文（学術雑誌）

CO(2) separation facilitated by task-specific ionic liquids using a supported liquid membrane
Shoji Hanioka, Tatsuo Maruyama, Tomohiro Sotani, Masahiro Teramoto, Hideto Matsuyama, Kazunori Nakashima, Misa Hanaki, Fukiko Kubota, Masahiro Goto
JOURNAL OF MEMBRANE SCIENCE, 314, 1-2, 1, 4, ELSEVIER SCIENCE BV, 2008年04月
英語, 研究論文（学術雑誌）, We report a supported liquid membrane (SLM) based on a task-specific ionic liquid to achieve the selective and facilitated CO, transport through the membrane. The prepared SLM facilitated by the amine-terminated ionic liquid showed high selectivity and high stability (more than 260 days) for CO(2) separation from the CO(2)/CH(4) gas mixture. (C) 2008 Elsevier B.V. All rights reserved.

A rapid assay of protease activity in ionic liquids using chromogenic substrates　　　　　　　　　　　　　　　
Kazunori Nakashima, Tatsuo Maruyama, Masahiro Goto, Noriho Kamiya
Analytical Biochemistry, Vol. 374 Issue: 2 Pages: 2, 2008年03月, ［査読有り］
英語, 研究論文（学術雑誌）

Spectrophotometric assay for protease activity in ionic liquids using chromogenic substrates
Kazunorl Nakashima, Tatsuo Maruyama, Noriho Kamiya, Masahiro Goto
ANALYTICAL BIOCHEMISTRY, 374, 2, 285, 290, ACADEMIC PRESS INC ELSEVIER SCIENCE, 2008年03月
英語, 研究論文（学術雑誌）, A new spectrophotometric assay has been developed to evaluate protease activity in ionic liquids (ILs). The assay consists of two strategies to enable real-time spectrometric analysis of enzymatic reaction in ILs. First, enzymes are modified with a comb-shaped poly(ethylene glycol), PM13, to obtain a transparent enzyme solution in IL. Second, a chromogenic substrate is used to follow the enzymatic reaction in IL. p-Nitroaniline-derivatized substrates are subjected to protease-catalyzed alcoholysis to release chromogenic p-nitroaniline that can be quantitatively detected by a UV-Vis spectrophotometer. By using this method, we can evaluate protease activity in ILs quite easily without separation of products from the reaction mixture. The availability of the novel assay system was demonstrated in a kinetic analysis of subtilisin-catalyzed reaction in the IL 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([Emim][Tf2N]) under different reaction conditions. Because two different serine proteases, subtilisin and alpha-chymotrypsin, substantially retained its original substrate specificity in the IL, the assay can be extended to other enzymes by using suitable chromogenic substrates. (C) 2007 Elsevier Inc. All rights reserved.

Extraction of lanthanide ions with an organophosphorous extractant into ionic liquids
Fukiko Kubota, Yusuke Koyanagi, Kazunori Nakashima, Kojiro Shimojo, Noriho Kamiya, Masahiro Goto
SOLVENT EXTRACTION RESEARCH AND DEVELOPMENT-JAPAN, 15, 81, 87, JAPAN ASSOC SOLVENT EXTRACTION, 2008年
英語, 研究論文（学術雑誌）, Extraction of lanthanide ions was carried out with the organophosphorous extractant PC-88A dissolved in an imidazolium-based ionic liquid. PC-88A was soluble in ionic liquids having long-chain alkyl substituents such as octyl and dodecyl groups, [C(8)mim] and [C(12)mim][TFSI], although short-chain imidazolium ionic liquids could not solubilize the extractant. The extraction equilibrium observed in the ionic liquid system was similar to that in the n-dodecane system, and the extraction behavior could be explained by the same proton exchange mechanism as for the conventional organic solvent system, although the extraction efficiency was not improved. An ionic liquid having shorter. alkyl chain [C(8)mim] showed a higher extraction ability than [C(12)mim][TFSI]. Stripping of the metal ions from the ionic liquids was also examined. Quantitative stripping of the metal ions was achieved by nitric acid in the [C(12)mim][TFSI] system.

Water-in-ionic liquid microemulsions as a new medium for enzymatic reactions
Muhammad Moniruzzaman, Noriho Kamiya, Kazunori Nakashima, Masahiro Goto
GREEN CHEMISTRY, 10, 5, 497, 500, ROYAL SOC CHEMISTRY, 2008年
英語, 研究論文（学術雑誌）, The insolubility of enzymes in most ionic liquids has been overcome by the formation of aqueous microemulsion droplets in a hydrophobic ionic liquid stabilized by a layer of anionic surfactant sodium bis( 2- ethyl- 1- hexyl) sulfosuccinate ( AOT) in the presence of 1- hexanol as a cosurfactant and the catalytic activity of one of the enzymes studied ( lipase PS) became higher than in microemulsions of AOT in isooctane.

Perfluorocarbon-based liquid-liquid extraction for separation of transition metal ions
Tatsuo Maruyama, Kazunori Nakashima, Fukiko Kubota, Masahiro Goto
ANALYTICAL SCIENCES, 23, 7, 763, 765, JAPAN SOC ANALYTICAL CHEMISTRY, 2007年07月
英語, 研究論文（学術雑誌）, We report a liquid-liquid extraction system based on perfluorocarbon (fluorous-solvent extraction) that allows selective extraction of metal ions from aqueous and organic phases to a perfluorocarbon phase (FC-72) with perfluorinated beta-diketone (1,1,1,5,5,6,6,6-octafluoro-2,4-hexanedione), which can be followed by backward extraction using 1 M nitric acid.

Extraction of cytochrome c by a functionalized ionic liquid containing a crown ether
Fukiko Kubota, Yusuke Koyanagi, Kazunori Nakashima, Kojiro Shimojo, Noriho Kamiya, Masahiro Goto
SOLVENT EXTRACTION RESEARCH AND DEVELOPMENT-JAPAN, 14, 115, 120, JAPAN ASSOC SOLVENT EXTRACTION, 2007年
英語, 研究論文（学術雑誌）, To verify the applicability of functionalized ionic liquids, so-called 'task-specific ionic liquids', to liquid-liquid extraction as solvents possessing extraction ability, we carried out the extraction of a protein cytochrome c (Cyt-c) with an ionic liquid with an attached crown ether moiety in the imidazolium cation. The functionalized ionic liquid, [18C6mim][PF6], was dissolved in two different ionic liquids as diluents, one having a hydroxyethyl group, [C(2)OHmim][Tf2N], and the other an ethyl group, [C(2)min][Tf2N], respectively. The transfer of Cyt-c from the aqueous phase to the ionic liquid phase took place with [18C6mim][PF6] in the [C(2)OHmim][Tf2N] system. The functionalized ionic liquid with the crown ether attached provided the similar extraction behavior to that using dicyclohexano-18-crown-6 (DCH18C6) as the extractant. Although the extraction ability was lower than that of DCH18C6, the functionalized ionic liquid system gave a better stripping performance than the ordinary crown ether system. The extraction efficiency was not influenced by operating temperature when the concentration of [18C6mim] was high whereas it was greatly affected by temperature at low [18C6mim] concentration. The ftinctionalized ionic liquids showed an extremely higher extraction performance compared to that of the ordinary ionic liquids, which have no coordination sites for the target molecule.

Activation of lipase in ionic liquids by modification with comb-shaped poly(ethylene glycol)
Kazunori Nakashima, Jun Okada, Tatsuo Maruyama, Noriho Kamiya, Masahiro Goto
SCIENCE AND TECHNOLOGY OF ADVANCED MATERIALS, 7, 7, 692, 698, NATL INST MATERIALS SCIENCE, 2006年10月
英語, 研究論文（学術雑誌）, Outstanding activation of an enzyme in ionic liquids (ILs) has been demonstrated by covalent modification with comb-shaped polytethylene glycol) (PEG) (PM13). Candida rugosa lipase modified with PM13 (PM13-CRL) was readily solubilized. in all the ILs tested ([Emim][Tf2N], [C(2)OC(1)mim][Tf2N] and [C(2)OHmim][Tf2N]) containing 0.5% (v/v) of water, whereas native lipase did not dissolve in any of the ILs. The results for transesterification of 2-phenyl-1-propanol with vinyl acetate using lipase in ILs revealed that the PM13-CRL conjugate exhibits a high catalytic activity while suspended native lipase shows little activity. The hydrophobicity of ILs somewhat affected the enzyme activity and a more hydrophobic IL such as [Emim][Tf2N] was preferable for the lipase reaction, as was also observed in enzymatic reaction in conventional organic solvents. The enzyme activities in ILs were much higher than those in organic solvents, the excellent activity being associated with unique properties such as the hydrophobicity and the high polarity of ILs. Furthermore, the PM13-CRL conjugate exhibited a high storage stability in [Emim][Tf2N], (c) 2006 NIMS and Elsevier Ltd. All rights reserved.

Homogeneous enzymatic reactions in ionic liquids with poly(ethylene glycol)modified subtilisin
Kazunori Nakashima, Tatsuo Maruyama, Noriho Kamiya, Masahiro Goto
ORGANIC & BIOMOLECULAR CHEMISTRY, 4, 18, 3462, 3467, ROYAL SOC CHEMISTRY, 2006年
英語, 研究論文（学術雑誌）, Subtilisin Carlsberg was covalently modified with comb-shaped poly( ethylene glycol) (PM13). PM13-modified subtilisin (PM13-Sub) was readily solubilized in three different ionic liquids (ILs), i.e., [Emim][Tf2N], [C(2)OC(1)mim][Tf2N] and [C(2)OHmim][Tf2N]. Analysis of homogeneous enzymatic reactions in the ILs revealed that PM13-Sub exhibited excellent catalytic performance while the native enzyme suspended in ILs showed no activity. Hydrophobicity of ILs slightly affected enzyme activity, and the relatively hydrophobic IL [Emim][Tf2N] was the preferred medium for enzymatic reactions, similar to enzymatic reactions in conventional organic solvents. Enzyme activity was much higher in [Emim][Tf2N] than in conventional organic solvents, and excellent activity was associated with unique properties of ILs such as hydrophobicity and high polarity. Furthermore, PM13-Sub showed good stability in [Emim][Tf2N], and maintained 80% of its initial activity after 60 h.

Crown ether-mediated extraction and functional conversion of cytochrome c in ionic liquids
K Shimojo, K Nakashima, N Kamiya, M Goto
BIOMACROMOLECULES, 7, 1, 2, 5, AMER CHEMICAL SOC, 2006年01月
英語, 研究論文（学術雑誌）, We report that a macrocyclic ligand enables transfer of a protein from an aqueous phase to ionic liquids. The extraction behavior of heme protein cytochrome c (Cyt-c) from an aqueous phase into ionic liquids was investigated with crown ethers. A hydroxyl-group-containing ionic liquid with dicyclohexano-18-crown-6 was found to be capable of quantitative partitioning of Cyt-c, whereas the protein transfer using conventional organic solvents was negligibly small. Furthermore, we clarified that Cyt-c solubilized in ionic liquids caused a structural transformation of Cyt-c, which triggers its functional conversion from an electron-transfer protein to peroxidase.

Feasibility of ionic liquids as alternative separation media for industrial solvent extraction processes
K Nakashima, F Kubota, T Maruyama, M Goto
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH, 44, 12, 4368, 4372, AMER CHEMICAL SOC, 2005年06月
英語, 研究論文（学術雑誌）, Extraction of rare earth metals into ionic liquids (ILs) from aqueous solutions was investigated using octyl(phenyl)-N,N-diisobutylcarbamoylmethyl phosphine oxide (CMPO) as an extractant. Use of ILs greatly enhanced the extraction efficiency and selectivity of CMPO for metal ions compared to when n-dodecane was used as the extracting solvent. The extraction mechanism has been studied by slope analysis and extraction tests, and these confirmed that the metal extraction proceeds via a cation-exchange mechanism. Furthermore, stripping of metals from ILs into an aqueous phase by complexing agents and recycling of the extracting ILs phase was successfully accomplished.

Comb-shaped poly(ethylene glycol)-modified subtilisin Carlsberg is soluble and highly active in ionic liquids
K Nakashima, T Maruyama, N Kamiya, M Goto
CHEMICAL COMMUNICATIONS, 34, 4297, 4299, ROYAL SOC CHEMISTRY, 2005年
英語, 研究論文（学術雑誌）, Subtilisin Carlsberg conjugated with comb-shaped poly( ethylene glycol) was solubilized in common ionic liquids without adding water, and exhibited higher transesterification activity in an ionic liquid, [Emim][Tf2N], than in organic solvents commonly used for enzymatic biotransformation.

Ionic liquids as a novel solvent for lanthanide extraction
K Nakashima, F Kubota, T Maruyama, M Goto
ANALYTICAL SCIENCES, 19, 8, 1097, 1098, JAPAN SOC ANALYTICAL CHEMISTRY, 2003年08月
英語, 研究論文（学術雑誌）, Octyl(phenyl)-N,N-diisobutylcarbamoylmethyl phosphine oxide (CMPO) dissolved in an ionic liquids, 1-butyl-3-methylimidazolium hexafluorophosphate, greatly enhances extractability and selectivity of lanthanide cations compared to that dissolved in conventional organic solvents; further, the recovery of lanthanides extracted into ionic liquids can be accomplished using several stripping solutions containing complexing agents. The possibility of utilizing ionic liquids as novel separation media in an industrial liquid-liquid extraction process was demonstrated.

Extraction of amino acids by calixarenes in an aliphatic organic solvent
K. Nakashima, T. Oshima, M. Goto
Solvent Extraction Research and Development, Japan, 9, 69, 79, Japanese Association of Solvent Extraction, 2002年
英語

Engineered Escherichia coli cell capable of specific binding to metal surface　　　　　　　　　　　　　　　
K. Nakashima, Y. Iwata, S. Kawasaki, ACS Fall 2019 National Meeting & Exposition, San Diego, United States, 2019年08月
英語

Microbially induced carbonate precipitation assisted by poly-L-lysine: ecofriendly approach inspired by nature　　　　　　　　　　　　　　　
T.H.K. Nawarathna, K. Nakashima, S. Kawasaki, ACS Fall 2019 National Meeting & Exposition, San Diego, United States, 2019年08月
英語

Beachrock identification using geology and geophysical approaches in Indonesia　　　　　　　　　　　　　　　
Daryono L. R, Nakashima K, Kawasaki S, Titisari A. D, Barianto D. H, Suyanto I, Rahmadi A, Proceedings of International Symposium on Earth Resources Management and Environment, ISERME 2019, 51, 59, 2019年08月
英語

Zinc and Lead Biosorption by Oceanobacillus Profundus Kbz 3-2: a Bacterial Strain Resistant to Metals Isolated from Metal polluted Soils in Kabwe, Zambia　　　　　　　　　　　　　　　
Wilson Mwandira, Kazunori Nakashima, Satoru Kawasaki, Mayumi Ito, Tsutomu Sato, Toshifumi Igarashi, Meki Chirwa, Kawawa Banda, Imasiku Nyambe, Shouta Nakayama, Mayumi Ishizuka, Proceedings of the 14th Asian Congress on Biotechnology (ACB2019), 2019年07月
英語

Biological Control of Filament Formation Composed of Silica-polymerizing Enzymes　　　　　　　　　　　　　　　
Kazunori Nakashima, Junnosuke Okamoto, Satoru Kawasaki, Proceedings of the 14th Asian Congress on Biotechnology (ACB2019), 2019年07月
英語

Bio-cementation for Slope Soil Stabilization againstSurface Erosion: A Bench-scale Preliminary Investigation　　　　　　　　　　　　　　　
S. Gowthaman, K. Nakashima, K. Ebina, S. Kawasaki, Proceedings of the 53rd US Rock Mechanics/Geomechanics Symposium, 2019年06月
英語

Development of small scale biocemented rocks based on natural beachrock cement characteristics as a novel approach towards coastal erosion mitigation　　　　　　　　　　　　　　　
P. G. N. Nayanthara, A. B, N. Dassanayake, K. Nakashima, S. Kawasaki, Proceedings of the 53rd US Rock Mechanics / Geomechanics Symposium, 2019年06月
英語

Evaluating possible avenues for soil improvement by biocementation in Sri Lanka: A preliminary investigation　　　　　　　　　　　　　　　
P. G. N. Nayanthara, A. B. N, Dassanayake, kazunori Nakashima, Satoru Kawasaki, Proceedings of the Eighth International Conference of Geotechnique, Construction Materials and Environment (GEOMATE 2018), 759, 764, 2018年11月
英語

Bio-inspired stabilization of embankment soil mediating Psychrobacillus sp. and low-grade chemicals: Preliminary laboratory investigation　　　　　　　　　　　　　　　
Sivakumar Gowthaman, Shumpei Mitsuyama, Kazunori Nakashima, Masahiro Komatsu, Satoru Kawasaki, Proceedings of the Eighth International Conference of Geotechnique, Construction Materials and Environment (GEOMATE 2018), 163, 168, 2018年11月
英語

Experimental optimization of biocement formation: Alternative countermeasure for surface erosion of cut slope　　　　　　　　　　　　　　　
Gowthaman S, Nakashima K, Ebina K, Kawasaki S, Proceedings of International Symposium on Earth Resources Management and Environment, ISERME 2018, 97, 103, 2018年08月, ［査読有り］
英語

Applicability of coastal ureolytic bacteria to coastal protection in Greece　　　　　　　　　　　　　　　
Md. Al Imran, Kazunori Nakashima, Niki Evelpidou, Satoru Kawasaki, 2018 International Conference on Geomechanics and Engineering (ICGE18), 2018年08月, ［査読有り］
英語

A preliminary investigation on isolation and identification of marine bacteria for biocementation in nearshore environments　　　　　　　　　　　　　　　
Nayanthara P. G. N, Dassanayake A. B. N, Nakashima K, Kawasaki S, Proceedings of International Symposium on Earth Resources Management and Environment, ISERME 2018, 111, 118, 2018年08月
英語

Microbially induced carbonate precipitation for expressway slope protection　　　　　　　　　　　　　　　
Mitsuyama, S, Nakashima, K, Komatsu, M, Kawasaki, S, Abstract Proceedings of the 1st International KAMPAI Symposium on Sustainable Management of Resources and Environment in the 21st Century, 23, 2017年11月
英語

Effect of cationic bio-polymer on CaCO3 crystallization by microbe　　　　　　　　　　　　　　　
T.H.K. Nawarathna, Kazunori Nakashima, Satoru Kawasaki, Abstract Proceedings of the 1st International KAMPAI Symposium on Sustainable Management of Resources and Environment in the 21st Century, 24, 2017年11月
英語

Immobilization of Lead-Contaminated Mine Waste by Pararhodobacter sp.　　　　　　　　　　　　　　　
Mwandira, W, Nakashima, K, Kawasaki, S, Chirwa, M, Banda, K.E, Nyambe, I.A, Abstract Proceedings of the 1st International KAMPAI Symposium on Sustainable Management of Resources and Environment in the 21st Century, 39, 2017年11月
英語

Effect of Organic biopolymer on the microbially induced carbonate precipitation and its morphology　　　　　　　　　　　　　　　
Thiloththama Hiranya, Kumari Nawarathna, Kazunori Nakashima, Satoru Kawasaki, Proceedings of the Seventh International Conference of Geotechnique, Construction Materials and Environment (GEOMATE 2017), 7, 1, 719, 724, 2017年11月
英語

Bioremediation of lead-contaminated mine waste using microbially induced carbonate precipitation　　　　　　　　　　　　　　　
Wilson Mwandira, Kazunori Nakashima, Satoru Kawasaki, Proceedings of International Symposium on Earth Resources Management and Environment, ISERME 2017, 21, 25, 2017年08月
英語

Efect of organic bio-polymer on bio-mineralization of CaCO3　　　　　　　　　　　　　　　
T.H.K. Hiranya, Kazunori Nakashima, Satoru Kawasaki, Proceedings of International Symposium on Earth Resources Management and Environment, ISERME 2017, 59, 66, 2017年08月
英語

Solubilization and functional evaluation of silica-polymerizing enzyme　　　　　　　　　　　　　　　
Hidetoshi Oguri, Kazunori Nakashima, Satoru Kawasaki, The 13th the Asian Congress on Biotechnology 2017 (ACB2017), 2017年07月
英語

Evaluation of porosity in biogrouted sand using microfocus X-ray CT　　　　　　　　　　　　　　　
Shumpei Mitsuyama, Kazunori Nakashima, Satoru Kawasaki, Proceedings of the Sixth International Conference of Geotechnique, Construction Materials and Environment (GEOMATE 2016), 145, 150, 2016年11月
英語

3. 遊離脂肪酸含有量の高い植物油を原料利用できるイオン交換樹脂法を用いたパイロットスケールの高品質バイオディーゼル製造装置の開発
北川,大柳, 斯琴髙娃, 中島, 丹羽,南,米本, 化学工学論文集, 42, 1, 30, 36, 2016年, ［査読有り］
A simple production process was developed for obtaining high quality biodiesel from various vegetable oils with high free fatty acid content using ion-exchange resin catalysts. A fully automated pilot-scale apparatus was designed based on the reported results using bench-scale apparatus and constructed. In addition to fatty acid methyl ester (FAME), fatty acid ethyl ester (FAEE), which has attracted attention as an environmentally preferable biodiesel, was both produced from cheaper non-edible oil with 50 wt% FFA content. Both biodiesel products fully met the international fuel standard speciications without downstream puriication processes other than removal of alcohol. he caloriic values of FAEE were higher than those of FAME, which promises improved fuel economy and horsepower., SOC CHEMICAL ENG JAPAN, 日本語

3P-023 Bacillus subtilis由来Misticタンパク質を利用した大腸菌によるシリカ重合酵素の可溶性発現(酵素学,酵素工学,一般講演)
長谷川 凛, 中島 一紀, 北川 尚美, 米本 年邦, 日本生物工学会大会講演要旨集, 67, 276, 276, 2015年
日本生物工学会, 日本語

2P-047 バクテリア由来エクスパンシンとエンドグルカナーゼからなる融合酵素の作製とセルロース分解挙動(酵素学,酵素工学,一般講演)
中島 一紀, 遠藤 孝治, 北川 尚美, 米本 年邦, 日本生物工学会大会講演要旨集, 66, 118, 118, 2014年
日本生物工学会, 日本語

3-11-3 イオン交換樹脂法によるパイロットプラントを用いた高品質バイオディーゼルの連続製造(Session 3-11 BDF等1)
北川 尚美, 大柳 友克, 斯琴高 娃, 中島 一紀, 米本 年邦, 日本エネルギー学会大会講演要旨集, 23, 148, 149, 2014年
This study was aimed at the pilot plant production of high quality biodiesel, which fully satisfies fuel specifications, from the cheaper non-edible oil with high free fatty acid content. Not only the fatty acid methyl ester (FAME), but also the fatty acid ethyl ester (FAEE), received much attention as more environmentally preferable biodiesel, was produced by the plant. Both biodiesel products were fully met the fuel standard specifications without any downstream purification processes except for removing alcohol. The calorific values of FAEE were higher than those of FAME and this meant that the fuel economy and horse power of FAEE will be improved., 一般社団法人日本エネルギー学会, 日本語

脂肪酸100%の油をも原料利用可能な高品質バイオディーゼル連続製造プロセスの開発　　　　　　　　　　　　　　　
北川尚美, 中島一紀, 米本年邦, ケミカルエンジニアリング,化学工業社, 59, 2, 112, 118, 2014年

脂肪酸100％の油をも原料利用可能な高品質バイオディーゼル連続製造プロセスの開発　　　　　　　　　　　　　　　
北川尚美, 中島一紀, 米本年邦, ケミカルエンジニヤリング, 59, 2, 20, 26, 2014年

脂肪酸100％の油をも原料利用可能な高品質バイオディーゼル連続製造プロセスの開発　　　　　　　　　　　　　　　
北川尚美, 中島一紀, 米本年邦, ケミカルエンジニヤリング, 59, 2, 20, 26, 2014年

金属イオンを接着剤として作られる中空タンパク質粒子　　　　　　　　　　　　　　　
中島一紀, 生物工学会誌, 91巻, 5号, 258, 2013年

金属イオンを接着剤として作られるタンパク質中空粒子(バイオミディア)
中島 一紀, 生物工学会誌 : seibutsu-kogaku kaishi, 91巻, 5号, 258, 258, 2013年
日本生物工学会, 日本語

幅広い溶媒をゲル化可能な低分子ゲル化剤
水口奈美, 宝得一貴, 山木大輔, 天能精一郎, 中島一紀, 後藤雅宏, 水畑穣, 丸山達生, 高分子学会予稿集(CD-ROM), 61, 1, 2012年

4Ia01 セルロースの酵素分解における超音波前処理の効果(バイオマス,資源,エネルギー工学,一般講演)
中島 一紀, 佐藤 拓海, 北川 尚美, 米本 年邦, 日本生物工学会大会講演要旨集, 64, 239, 239, 2012年
日本生物工学会, 日本語

イオン液体耐性セルラーゼの単離と酵素特性解析
窪田有華, 工藤基徳, 仲島菜々実, 中島一紀, 岡崎文美, 荻野千秋, 近藤昭彦, 酵素工学研究会講演会講演要旨集, 68th, 2012年

イオン液体耐性セルラーゼの探索と機能解析
窪田有華, 山口剛示, 仲島菜々実, 工藤基徳, 中島一紀, 岡崎文美, 荻野千秋, 近藤昭彦, 日本生物工学会大会講演要旨集, 64th, 2012年

1Ap14 イオン液体を利用したバイオマスの前処理・糖化・発酵技術の開発(バイオマス・資源・エネルギー工学,一般講演)
荻野 千秋, 中島 一紀, 山口 剛示, 窪田 有華, 片平 悟史, 石田 亘広, 徳原 渡, 則武 義幸, 近藤 昭彦, 日本生物工学会大会講演要旨集, 63, 24, 24, 2011年
日本生物工学会, 日本語

1Ap13 セルラーゼ分泌酵母によるイオン液体処理バイオマスからのエタノール生産(バイオマス・資源・エネルギー工学,一般講演)
片平 悟史, 中村 里沙, 徳原 渡, 則武 義幸, 中島 一紀, 神谷 典穂, 荻野 千秋, 石田 亘広, 日本生物工学会大会講演要旨集, 63, 23, 23, 2011年
日本生物工学会, 日本語

水・有機溶媒・食用油・イオン液体をゲル化可能な新規低分子ゲル化剤の開発
水口 奈美, 宝得 一貴, 丸山 達生, 大向 吉景, 中島 一紀, 後藤 雅宏, 松山 秀人, 化学工学会 研究発表講演要旨集, 2010, 1088, 1088, 2010年
公益社団法人 化学工学会, 日本語

高効率バイオディーゼル生産を目的としたWhole-cell biocatalystによる新規リパーゼ複合系の開発
足立 大輔, 中島 一紀, 荻野 千秋, 近藤 昭彦, 化学工学会 研究発表講演要旨集, 2010, 1008, 1008, 2010年
公益社団法人 化学工学会, 日本語

3P-2043 イオン液体を利用したバイオマスの前処理・糖化・発酵技術の開発(その3)(5c バイオマス,資源,エネルギー工学,一般演題,環境バイオテクノロジー,伝統の技と先端科学技術の融合)
山口 剛示, 中島 一紀, 山田 亮祐, 荻野 千秋, 近藤 昭彦, 日本生物工学会大会講演要旨集, 22, 154, 154, 2010年
日本生物工学会, 日本語

バイオリファイナリー実現に向けたセルロース分解酵素の新たな選抜法　　　　　　　　　　　　　　　
中島一紀, 化学工学, 74, 5, 248, 2010年

次世代燃料・化成品原料製造に向けたバイオリファイナリー戦略　　　　　　　　　　　　　　　
近藤昭彦, 荻野千秋, 蓮沼誠久, 田中勉, 中島一紀, 生物工学会誌, 88, 7, 333, 335, 2010年

バイオマスからのバイオ燃料生産に向けた戦略　　　　　　　　　　　　　　　
近藤昭彦, 荻野千秋, 蓮沼誠久, 田中勉, 中島一紀, 月刊バイオインダストリー シーエムシー出版, 27, 11, 6, 12, 2010年

バイオリファイナリー実現に向けたセルロース分解酵素の新たな選抜法　　　　　　　　　　　　　　　
中島一紀, 化学工学, 74, 5, 248, 2010年

次世代燃料・化成品原料製造に向けたバイオリファイナリー戦略　　　　　　　　　　　　　　　
近藤昭彦, 荻野千秋, 蓮沼誠久, 田中勉, 中島一紀, 生物工学会誌, 88, 7, 333, 335, 2010年

バイオマスからのバイオ燃料生産に向けた戦略　　　　　　　　　　　　　　　
近藤昭彦, 荻野千秋, 蓮沼誠久, 田中勉, 中島一紀, 月刊バイオインダストリー,シーエムシー出版, 27, 11, 6, 12, 2010年

カルボン酸系新規抽出剤による希土類金属のイオン液体抽出
久保田 富生子, 小柳 裕介, 下条 晃司郎, 中島 一紀, 神谷 典穂, 後藤 雅宏, 化学工学会 研究発表講演要旨集, 2009, 230, 230, 2009年
公益社団法人 化学工学会, 日本語

疾病関連生体触媒に応答した超分子ハイドロゲル形成
香田 大輔, 丸山 達生, 中島 一紀, 神谷 典穂, 後藤 雅宏, 化学工学会 研究発表講演要旨集, 2009, 603, 603, 2009年
公益社団法人 化学工学会, 日本語

3S1a03 イオン液体の活用によるセルロース前処理と酵素糖化の同時促進(バイオマス糖化技術の新展開,シンポジウム)
神谷 典穂, 松下 雄一, 植田 美紗, 中島 一紀, 後藤 雅宏, 趙 盛進, 石田 亘広, 高橋 治雄, 日本生物工学会大会講演要旨集, 21, 200, 200, 2009年
日本生物工学会, 日本語

菌体触媒を用いたバイオディーゼル生産におけるイオン液体の利用
中島 一紀, 荒井 章吾, 谷野 孝徳, 荻野 千秋, 近藤 昭彦, 福田 秀樹, 化学工学会 研究発表講演要旨集, 2009, 912, 912, 2009年
公益社団法人 化学工学会, 日本語

プロテアーゼに応答するペプチド性超分子ゲル化剤の創製
香田 大輔, 丸山 達生, 中島 一紀, 後藤 雅宏, 化学工学会 研究発表講演要旨集, 2008, 946, 946, 2008年
公益社団法人 化学工学会, 日本語

水-イオン液体混合溶媒中でのセルロースの酵素触媒的分解
松下 雄一, 植田 美紗, 中島 一紀, 神谷 典穂, 後藤 雅宏, 成田 麻美子, 石田 亘広, 高橋 治雄, 化学工学会 研究発表講演要旨集, 2008, 989, 989, 2008年
公益社団法人 化学工学会, 日本語

2Ga06 イオン液体ゲルからなる新規バイオコンポジット材料の開発(酵素学,酵素工学,タンパク質工学,一般講演)
中島 一紀, 丸山 達生, 神谷 典穂, 後藤 雅宏, 日本生物工学会大会講演要旨集, 20, 177, 177, 2008年
日本生物工学会, 日本語

2Gp15 イオン液体共存下におけるセルロースの酵素糖化処理法(酵素学,酵素工学,タンパク質工学,一般講演)
神谷 典穂, 松下 雄一, 植田 美紗, 中島 一紀, 後藤 雅宏, 成田 麻美子, 石田 亘広, 高橋 治雄, 日本生物工学会大会講演要旨集, 20, 183, 183, 2008年
日本生物工学会, 日本語

イオン液体からなるゲルへの酵素の封入とその反応特性
中島 一紀, 丸山 達生, 神谷 典穂, 後藤 雅宏, 化学工学会 研究発表講演要旨集, 2008, 424, 424, 2008年
公益社団法人 化学工学会, 日本語

イオン液体を媒体とした希土類金属の抽出挙動の検討
小柳 裕介, 久保田 富生子, 中島 一紀, 下条 晃司郎, 神谷 典穂, 後藤 雅宏, 化学工学会 研究発表講演要旨集, 2008, 104, 104, 2008年
公益社団法人 化学工学会, 日本語

Formation of Nanoemulsions in a Room-Temperature Ionic Liquid
Muhammad Moniruzzaman, 神谷 典穂, 中島 一紀, 後藤 雅宏, 化学工学会 研究発表講演要旨集, 2008, 599, 599, 2008年
公益社団法人 化学工学会

新たな非水溶媒イオン液体中での酵素反応　　　　　　　　　　　　　　　
中島一紀, 神谷典穂, 後藤雅宏, 月刊バイオインダストリー シーエムシー出版, 25, 7, 24, 34, 2008年

新たな非水溶媒イオン液体中での酵素反応 (特集 化学品量産プロセスを志向する酵素研究)
中島 一紀, 神谷 典穂, 後藤 雅宏, バイオインダストリー, 25, 7, 24, 34, 2008年
シーエムシー出版, 日本語

イオン液体を用いた促進輸送膜によるCO2分離
埴岡 昌司, 曽谷 知弘, 寺本 正明, 松山 秀人, 後藤 雅宏, 久保田 富生子, 花木 美紗, 中島 一紀, 化学工学会 研究発表講演要旨集, 2007, 777, 777, 2007年
公益社団法人 化学工学会, 日本語

ヒスチジン含有ペプチド性低分子ハイドロゲル化剤の創製と脂肪酸鎖の影響の評価
香田 大輔, 丸山 達生, 園川 沙織, 中島 一紀, 後藤 雅宏, 化学工学会 研究発表講演要旨集, 2007, 832, 832, 2007年
公益社団法人 化学工学会, 日本語

酵素を封入したイオン液体ゲルの創製とその触媒特性
中島 一紀, 丸山 達生, 神谷 典穂, 後藤 雅宏, 化学工学会 研究発表講演要旨集, 2007, 833, 833, 2007年
公益社団法人 化学工学会, 日本語

イオン液体を用いた生体分子の抽出システムの開発
小柳 裕介, 久保田 富生子, 中島 一紀, 下条 晃司郎, 神谷 典穂, 後藤 雅宏, 化学工学会 研究発表講演要旨集, 2007, 658, 658, 2007年
公益社団法人 化学工学会, 日本語

イオン液体を用いた新規プロテアーゼ活性検出システムの開発
中島 一紀, 丸山 達生, 神谷 典穂, 後藤 雅宏, 化学工学会 研究発表講演要旨集, 2007, 404, 404, 2007年
公益社団法人 化学工学会, 日本語

Solubilization and functional changes of biomolecules in ionic liquids
Masahiro Goto, Kojiro Shimojo, Kazunori Nakashima, Polymer Preprints, Japan, 55, 4176, 4177, 2006年12月01日
This lecture reports on the protein transfer from an aqueous phase into ionic liquids (ILs) with dicyclohexano-18-crown-6 (DCH18C6), and the functional change of cytochrome c (Cyt-c) dissolved in ILs. Further, a protein is modified with comb-shaped poly (ethylene glycol), PM13. PM13modified subtilisin (PM13-Sub) could be solubilized clearly in a wide range of pure ILs. This markedly high activity in the IL was superior to that in organic solvents commonly used for enzymatic catalysis. PM13-Sub was also found to retain its catalytic activity in the ILs for a prolonged period.

生体触媒の新しい反応場としてのイオン液体 －水中から有機溶媒へ、そして今イオン液体へ－　　　　　　　　　　　　　　　
中島一紀, 後藤雅宏, 化学工学, 70, 2, 111, 113, 2006年

生体触媒の新しい反応場としてのイオン液体 －水中から有機溶媒へ、そして今イオン液体へ－　　　　　　　　　　　　　　　
中島一紀, 後藤雅宏, 化学工学, 70, 2, 111, 113, 2006年

Comb-shaped polyethylene glycol-modifled subtilisin soluble and highly active in ionic liquids
Masahiro Goto, Kazunori Nakashima, AIChE Annual Meeting, Conference Proceedings, 14358, 2005年12月01日
Subtilisin Carlsberg conjugated with comb-shaped polyethylene glycol was solubilized in common ionic liquids without adding water, and exhibited higher transesterification activity in ionic liquids than in organic solvents commonly used for enzymatic biotransformation. Many researchers are becoming increasingly interested in the application of ILs as reaction media for biotransformation. Recent works showed that enzymes exhibited their catalytic activities in pure ILs or IL/aqueous biphasic systems, providing many advantages such as high conversion rates, high enantioselectivity, and increased stability of enzymes. However, one of the most significant limitations in enzymatic reactions in ILs is the relatively low activity of enzymes suspended in ILs. Some ILs are known to dissolve enzymes with or without a small amount of water, however, dissolved enzymes show little catalytic activity presumably due to their conformational change in ILs. To overcome this limitation, several studies have been conducted to enhance enzymatic activity in ILs, involving the addition of a small amount of water to ILs, and immobilization of enzyme with solid supports. Polyethylene glycol (PEG) shows high solubility in ILs, and was found to provide high stability and dispersibility of enzymes in ILs. We previously showed the effective activation of lipases in ILs by physical complexation of lipases with PEG 20,000. Although some researchers attempted to improve solubility and activity of enzymes in ILs by covalent modification with PEG, chemical modification of enzymes with linear PEG did not offer sufficient solubility and catalytic activity in ILs. Here, we report the use of comb-shaped PEG as an enzyme modifier to solubilize an enzyme in ILs. Comb-shaped PEG, PM13 is a copolymer derivative of PEG and maleic anhydride with an approximate molecular weight of 13,000 and has multivalent reactive sites, acid anhydrides, which react preferentially with amino groups in a protein molecule. The potential utility of PM13 was validated in enzymatic catalysis in organic solvents. In the present study, we have demonstrated perfect solubilization and marked enhancement of catalytic activity of an enzyme in ILs by modification with PM13. To our knowledge, this great superiority of enzymatic catalysis in pure ILs compared with organic solvents has not yet been reported. In summary, we showed that comb-shaped PEG, PM13, is an excellent modifier to solubilize enzymes in ILs. This approach offers high enzymatic activity in pure ILs without immobilization of enzyme or addition of small amounts of water. We believe that this paper will stimulate researchers to develop further applications in the field of enzymology for the use of ILs.

Solubilization and high activity of enzymes in ionic liquids by modification with comb-shaped poly (ethylene glycol)
Kazunori Nakashima, Tatsuo Maruyama, Noriho Kamiya, Masahiro Goto, Polymer Preprints, Japan, 54, 4647, 4648, 2005年12月01日
Subtilisin Carlsberg was modified with comb-shaped poly (ethylene glycol), PM13. PM13 modified subtilisin (PM13-Sub) could be solubilized clearly in a wide range of pure ILs, whereas native subtilisin was not soluble in any ILs. Furthermore, PM13-Sub dissolved in ILs exhibited the excellent catalytic activity in transesterification of N-acetyl-L-phenylalanine ethyl ester with 1-butanol. This markedly high activity in the IL was superior to that in organic solvents commonly used for enzymatic catalysis. PM13-Sub was also found to retain its catalytic activity in the ILs for a prolonged period.

1C14-4 イオン液体への酵素の可溶化とその触媒特性(酵素学・酵素工学・タンパク質工学,一般講演)
中島 一紀, 丸山 達生, 神谷 典穂, 後藤 雅宏, 日本生物工学会大会講演要旨集, 17, 100, 100, 2005年
日本生物工学会, 日本語

イオン性液体中における均一酵素反応場の構築
中島 一紀, 丸山 達生, 神谷 典穂, 後藤 雅宏, 化学工学会 研究発表講演要旨集, 2005, 286, 286, 2005年
公益社団法人 化学工学会, 日本語

エコバイオリファイナリー―脱石油社会へ移行するための環境ものづくり戦略―　　　　　　　　　　　　　　　
シーエムシー出版, 2010年

酵素利用技術大系　　　　　　　　　　　　　　　
エヌ・ティー・エス, 2010年

エコバイオリファイナリー―脱石油社会へ移行するための環境ものづくり戦略―　　　　　　　　　　　　　　　
シーエムシー出版, 2010年

酵素利用技術大系　　　　　　　　　　　　　　　
エヌ・ティー・エス, 2010年

生物機能を駆使した選択的インテリジェント凝集システムの開発
科学研究費助成事業
2024年04月01日 - 2027年03月31日
中島 一紀, 廣吉 直樹, 五十嵐 健輔, 高野 力
日本学術振興会, 基盤研究(B), 北海道大学, 24K03104

天然および人工の有機・無機接着界面から発想する新たなバイオベース固化技術の創出
科学研究費助成事業
2021年04月01日 - 2024年03月31日
中島 一紀, 川崎 了, 五十嵐 健輔
日本学術振興会, 基盤研究(B), 北海道大学, 21H03627

デザイン可能なバイオベースの貴金属吸着剤の創製
科学研究費助成事業
2020年07月30日 - 2023年03月31日
中島 一紀
本研究では，バイオマスとタンパク質を組み合わせることで都市鉱山からの貴金属の回収が可能なバイオベースの金属イオン吸着剤を開発する。
昨年度の研究において，金結合タンパク質（AuBP）と多糖結合モジュール（CBM）を融合した融合タンパク質AuBP-CBMを作製し，そのAu3+吸着機能が確認された。そこで本年度は，様々な融合タンパク質のラインナップを作製し，そのセルロース吸着機能および金属吸着機能を調査した。融合タンパク質の作製の過程において，遺伝子構築およびタンパク質発現に成功したものを用いてその後の実験を行った。AuBP-CBMをベースタンパク質として，CBMのN末端およびC末端の両方にAuBPを配置したAuBP両端型，AuBP-CBM を2つ連結したCBMタンデム型を作製した。これら3つの融合タンパク質のセルロース吸着性および金属結合性はそれぞれ異なったが，最終的な効率を示すセルロースあたりのAu3+回収率はAuBP両端型が最も高かった。また，X線光電子分光法（XPS）により，セルロース上に吸着したAuがAu(0)であることを確認した。AuBP両端型を固定化したセルロースは，白金族および遷移金属（Au, Pt, Pd, Cu, Co, Ni, Zn）を含む溶液中からAuを高選択的に回収することが可能であり，セルロース上のAuはチオ尿素を用いて89%脱着することができた。この際，AuはAu+に酸化され，チオ尿素と錯体を形成したと考えられる。
また，ろ紙以外のセルロース材料として，高機能性材料として注目を集めているセルロースナノファイバーの利用を検討した。タンパク質の吸着性について調査したところ，ろ紙よりも3倍以上の高い吸着性を示すことが明らかとなった。
日本学術振興会, 挑戦的研究(萌芽), 北海道大学, 20K21853

バイオセメントと木質バイオマスを利用した重金属汚染の統合バイオレメディエーション
科学研究費助成事業
2018年04月01日 - 2021年03月31日
中島 一紀, 川崎 了
本研究では，高濃度の重金属で汚染された土壌をバイオセメント技術により封じ込めを行い，そこから流出した低濃度の重金属汚染水を重金属結合性バイオマスにより完全浄化することが可能なシステムの開発を目的とする。尿素分解酵素を分泌する微生物を用いたCaCO3析出により，モデル汚染土壌および実サンプルの固化と重金属の固定化に成功した。さらに，有機ポリマーを組み合わせたバイオセメントを開発し，さらなる強度の増大を達成した。また，タンパク質と天然高分子を用いた新規の重金属吸着剤を開発し，連続吸着システムを構築した。
日本学術振興会, 基盤研究(B), 北海道大学, 18H03395

自発的に無機材料とハイブリッド化する微生物細胞の創製と微生物燃料電池への応用
科学研究費助成事業
2015年04月01日 - 2017年03月31日
中島 一紀
本研究では，大腸菌E.coliで発現したシリカテインの凝集性について検討を行った。コールドショック発現系を用いることで，シリカテインの発現に成功した。タンパク質は不溶性として得られたが，リフォールディング操作により可溶化した。リフォールディングしたシリカテインを用いて凝集性を調査したところ，シリカテインはバッファー中では自己集合により凝集体を形成したが，尿素存在下では凝集が抑制された。シリカテインを細胞表層に配向させるために，Pseudomonas syringae由来InaK，およびE.coli由来OmpAを用いて細胞表層提示系を構築した。また，微生物燃料電池の基本システムを作製した。
日本学術振興会, 若手研究(B), 北海道大学, 15K18273

油糧バイオマスから健康機能物質とバイオ燃料の同時製造を実現する新反応・分離技術
科学研究費助成事業
2012年04月01日 - 2015年03月31日
米本 年邦, 北川 尚美, 中島 一紀
油糧バイオマスに含まれる抗酸化活性の高いビタミンE類（トコトリエノール、トコフェロール）や血中コレステロール濃度を下げる植物ステロールなどの脂溶性健康機能物質を選択的に回収すると同時に、軽油代替燃料となる高品質脂肪酸エステルを製造する独創的な反応・分離技術を開発した。溶媒との親和性に応じて大きく膨潤・収縮するイオン交換樹脂を充填する際に有効な容量可変式反応器を考案、油分を転化率100%で脂肪酸エステルに変換したところ、溶解度の低下によってステロールが室温で結晶化し、容易に回収できることを見出した。また、トコフェロールの回収率100%達成、トコトリエノールの高収率回収に世界に先駆け成功した。
日本学術振興会, 基盤研究(A), 東北大学, 24246127

米糠残渣油からのトコトリエノール回収とバイオディーゼル燃料合成
科学研究費助成事業
2009年 - 2011年
米本 年邦, 北川 尚美, 久保 正樹, 中島 一紀
本研究では、米糠から食用油を製造する工程で副生する残渣油(脱臭スカム油)から、健康機能物質トコトリエノールの回収と環境調和型バイオディーゼル燃料の生産を行う新規な反応・分離プロセスを構築することを目的とした。まず、回分系において、陽イオン交換樹脂を触媒とする遊離脂肪酸のエステル化、陰イオン交換樹脂を吸着剤とするトコトリエノールを含むビタミンE類の吸脱着による回収、陰イオン交換樹脂を触媒とするトリグリセリドのエステル交換を段階的に行った。そして、各反応や吸着挙動に及ぼす操作因子の影響を検討することで、各段階での目的に応じた適切な操作条件を明らかにした。この結果に基づき、樹脂を充填したカラム型反応器を作製し、各段階の連続プロセス化を行った。
日本学術振興会, 基盤研究(B), 東北大学, 21360373