研究者詳細 - 島内　寿徳

論文 - 島内　寿徳

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The structural evaluation of amyloid beta on lipid membranes 査読

Satoka Aoyagi, Miki Iwamura, Toshinori Shimanouchi, Yuta Yokoyama, Hideo Iwai

Surface and Interface Analysis 48 ( 11 ) 1096 - 1099 2016年11月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：WILEY-BLACKWELL

Amyloid beta (Aβ) adsorption onto lipid membranes depending on the condition of a lipid was investigated by means of time-of-flight secondary ion mass spectrometry (ToF-SIMS). Aβ aggregation depending on the different hardness of lipid membrane has not been clarified yet although it is important to understand Alzheimer's disease. Aβ (1–40) on three different lipid membranes having different transition temperatures has been evaluated using ToF-SIMS in the previous study, and in this study, the differences between Aβ on liquid crystalline-phase lipid membranes and that on gel-phase lipid membranes were investigated in order to clarify the mechanisms of aggregation and peptide folding change. ToF-SIMS secondary ion images clearly showed Aβ distribution on lipid membranes. Because ToF-SIMS data is extremely complicated although it contains rich information, it was analysed by principal component analysis (PCA). Score images indicated by PCA are consistent with the images of secondary ions related to Aβ and are clearer than the secondary ion images. Moreover, PCA results suggest the difference between Aβ on different lipid membranes in terms of amino acid fragment ions, and the orientation of Aβ on 1,2-dipalmitoyl-sn-glycero-3-phosphocholine was indicated. Copyright © 2016 John Wiley & Sons, Ltd.

DOI： 10.1002/sia.6086

Heparin promotes fibril formation by the N-terminal fragment of amyloidogenic apolipoprotein A-I. 査読国際誌

Shiho Mikawa, Chiharu Mizuguchi, Kazuchika Nishitsuji, Teruhiko Baba, Akira Shigenaga, Toshinori Shimanouchi, Naomi Sakashita, Akira Otaka, Kenichi Akaji, Hiroyuki Saito

FEBS letters 590 ( 20 ) 3492 - 3500 2016年10月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：WILEY-BLACKWELL

Glycosaminoglycans are known to be associated with extracellular amyloid deposits of various amyloidogenic proteins. In this study, we found that the glycosaminoglycan heparin greatly accelerates the elongation step in fibril formation by the N-terminal 1-83 fragment of human apolipoprotein A-I (apoA-I), especially in the amyloidogenic W50R variant. Using fragment peptides, we demonstrate that heparin significantly promotes β-transition and fibril formation of the highly amyloidogenic region spanning residues 44-65 and colocalizes with fibrils formed by the W50R variant. These results suggest the possible role of glycosaminoglycans in fibril formation by amyloidogenic apoA-I variants.

DOI： 10.1002/1873-3468.12426

ToF-SIMS analysis of amyloid beta aggregation on different lipid membranes. 国際誌

Yuta Yokoyama, Satoka Aoyagi, Toshinori Shimanouchi, Miki Iwamura, Hideo Iwai

Biointerphases 11 ( 2 ) 02A314 - 6 2016年6月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：AMER INST PHYSICS

Amyloid beta (Aβ) peptides are considered to be strongly related to Alzheimer's disease. Aβ peptides form a β-sheet structure on hard lipid membranes and it would aggregate to form amyloid fibrils, which are toxic to cells. However, the aggregation mechanism of Aβ is not fully understood. To evaluate the influence of the lipid membrane condition for Aβ aggregation, the adsorption forms of Aβ (1-40) on mixture membranes of lipid 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) and cholesterol β-d-glucoside (β-CG) were investigated by time-of-flight secondary ion mass spectrometry. As a result, Aβ adsorbed along the localized DMPC lipid on the mixture lipid membranes, whereas it was adsorbed homogeneously on the pure DMPC and β-CG membranes. Moreover, amino acid fragments that mainly existed in the n-terminal of Aβ (1-40) peptide were strongly detected on the localized DMPC region. These results suggested that the Aβ was adsorbed along the localized DMPC lipid with a characteristic orientation. These findings suggest that the hardness of the membrane is very sensitive to coexisting materials and that surface hardness is important for aggregation of Aβ.

DOI： 10.1116/1.4940706

Chemical Conversion and Liquid-Liquid Extraction of 5-Hydroxymethylfurfural from Fructose by Slug Flow Microreactor

Toshinori Shimanouchi, Yoshitaka Kataoka, Tatsuya Tanifuji, Yukitaka Kimura, Satoko Fujioka, Koichi Terasaka

AICHE JOURNAL 62 ( 6 ) 2135 - 2143 2016年6月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：WILEY-BLACKWELL

A dehydration of fructose in the water/methyl isobuthyl ketone (MIBK) biphasic system can yield 5hydroxymethylfulfural (IIMF) to be successfully extracted into the organic MIBK phase. The [IMF production and yield in MIRK phase was discussed by using a simplified model taking into consideration of the slug flow. The extraction resistance of IIMF across the interface between water and MIRK depended on the line velocity and the flow rate ratio. It was likely that the velocity field generated in the slug flow contributed to an increase in the mass transfer of IIMF. 2016 American Institute of Chemical Engineers AIChE J, 62: 2135-2143, 2016

DOI： 10.1002/aic.15201

Chemical Conversion and Liquid-Liquid Extraction of 5-Hydroxymethylfurfural from Fructose by Slug Flow Microreactor 査読

Toshinori Shimanouchi, Yoshitaka Kataoka, Tatsuya Tanifuji, Yukitaka Kimura, Satoko Fujioka, Koichi Terasaka

AICHE JOURNAL 62 ( 6 ) 2135 - 2143 2016年6月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：WILEY-BLACKWELL

A dehydration of fructose in the water/methyl isobuthyl ketone (MIBK) biphasic system can yield 5hydroxymethylfulfural (IIMF) to be successfully extracted into the organic MIBK phase. The [IMF production and yield in MIRK phase was discussed by using a simplified model taking into consideration of the slug flow. The extraction resistance of IIMF across the interface between water and MIRK depended on the line velocity and the flow rate ratio. It was likely that the velocity field generated in the slug flow contributed to an increase in the mass transfer of IIMF. 2016 American Institute of Chemical Engineers AIChE J, 62: 2135-2143, 2016

DOI： 10.1002/aic.15201

Detection of Fibrillization Process of Amyloid Beta Protein Using Arrayed Biosensor with Liposome Encapsulating Fluorescent Molecules

R. Imamura, T. Shimanouchi, N. Murata, K. Yamashita, M. Fukuzawa, M. Noda

PROCEEDINGS OF THE 30TH ANNIVERSARY EUROSENSORS CONFERENCE - EUROSENSORS 2016 168 1414 - 1417 2016年

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）出版者・発行元：ELSEVIER SCIENCE BV

We have successfully detected fibrillization process of amyloid-beta(1-40) protein (A beta(1-40)) as causative compounds of Alzheimer's disease by our developed bio array sensing system utilizing different phospholipid liposomes encapsulating fluorescent molecules. The fluorescent intensity is dependent on the leakage of fluorescent molecules through perturbed lipid membrane of liposome. Therefore, the intensity considerably depends on the liposome-A beta interaction strength on fibrillization process of A beta(1-40). It is noted that the behavior of the fluorescent intensity corresponded to that of our cantilever sensor when measuring the interaction. Moreover, difference in A beta(1-40) concentration or liposome-A beta(1-40) interaction strength was successfully discriminated by principal component analysis. Consequently, we believe that the fluorescent liposome sensor is very effective for discriminating aggregation and fibrillization processes and concentrations of A beta(1-40). (C) 2016 Published by Elsevier Ltd.

DOI： 10.1016/j.proeng.2016.11.400

Formation of lens-like vesicles induced via microphase separations on a sorbitan monoester membrane with different headgroups. 国際誌

Keita Hayashi, Hideka Iwai, Toshinori Shimanouchi, Hiroshi Umakoshi, Tomoyuki Iwasaki, Ayako Kato, Hidemi Nakamura

Colloids and surfaces. B, Biointerfaces 135 235 - 242 2015年11月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ELSEVIER SCIENCE BV

The microphase separation of lipid molecules on a vesicle membrane can be induced, depending on the difference in the geometric structures of their headgroups. Through cryo-transmission-electron-microscopy analysis, a lens-like vesicle was prepared by mixing 50 wt% Span 40 (sorbitan monopalmitate) and 50 wt% Tween 40 [polyoxyethylene (20) sorbitan monopalmitate]. Considering the molecular structures of Span 40 and Tween 40, the high-curvature region was mainly formed by Tween 40. As determined by Fourier-transform infrared spectroscopy, dielectric-dispersion analysis, and differential scanning calorimetry, a hydration layer was likely formed because polyoxyethylene conjugates with the headgroups of Tween 40. These investigations of the obtained self-assembled aggregates of nonionic surfactants with heterogeneous surfaces could contribute to the development of new types of biomaterials.

DOI： 10.1016/j.colsurfb.2015.07.071

Amyloidogenic Mutation Promotes Fibril Formation of the N-terminal Apolipoprotein A-I on Lipid Membranes. 国際誌

Chiharu Mizuguchi, Fuka Ogata, Shiho Mikawa, Kohei Tsuji, Teruhiko Baba, Akira Shigenaga, Toshinori Shimanouchi, Keiichiro Okuhira, Akira Otaka, Hiroyuki Saito

The Journal of biological chemistry 290 ( 34 ) 20947 - 20959 2015年8月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC

The N-terminal amino acid 1-83 fragment of apolipoprotein A-I (apoA-I) has a strong propensity to form amyloid fibrils at physiological neutral pH. Because apoA-I has an ability to bind to lipid membranes, we examined the effects of the lipid environment on fibril-forming properties of the N-terminal fragment of apoA-I variants. Thioflavin T fluorescence assay as well as fluorescence and transmission microscopies revealed that upon lipid binding, fibril formation by apoA-I 1-83 is strongly inhibited, whereas the G26R mutant still retains the ability to form fibrils. Such distinct effects of lipid binding on fibril formation were also observed for the amyloidogenic prone region-containing peptides, apoA-I 8-33 and 8-33/G26R. This amyloidogenic region shifts from random coil to α-helical structure upon lipid binding. The G26R mutation appears to prevent this helix transition because lower helical propensity and more solvent-exposed conformation of the G26R variant upon lipid binding were observed in the apoA-I 1-83 fragment and 8-33 peptide. With a partially α-helical conformation induced by the presence of 2,2,2-trifluoroethanol, fibril formation by apoA-I 1-83 was strongly inhibited, whereas the G26R variant can form amyloid fibrils. These findings suggest a new possible pathway for amyloid fibril formation by the N-terminal fragment of apoA-I variants: the amyloidogenic mutations partially destabilize the α-helical structure formed upon association with lipid membranes, resulting in physiologically relevant conformations that allow fibril formation.

DOI： 10.1074/jbc.M115.664227

Surface properties of woody thin boards composed of commercially available lignin and cellulose: Relationship between the orientation of lignin and water repellency

Toshinori Shimanouchi, Tomoya Kamba, Wei Yang, Satoka Aoyagi, Yukitaka Kimura

APPLIED SURFACE SCIENCE 347 406 - 413 2015年8月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ELSEVIER SCIENCE BV

Woody thin boards were prepared from lignin, cellulose, and water by compression molding at 180 degrees C and 25 MPa for 10 min. Boards with higher contact angles gave lower values of relative permittivity on their surface. Attenuated-total reflection Fourier transfer infrared spectroscopy suggested that more lignin existed on the surface of the boards with the high contact angle, which was also supported by scanning electron microscopy and atomic force microscopy. Our findings thus revealed that the orientation of lignin at the surface resulted in increased hydrophobicity of the surface and contributed to the enhancement of water repellency. (C) 2015 Published by Elsevier B.V.

DOI： 10.1016/j.apsusc.2015.03.139

Characterization of the Residue and Liquid Products Produced from Husks of Nuts from Carya cathayensis Sarg by Hydrothermal Carbonization

Wei Yang, Toshinori Shimanouchi, Yukitaka Kimura

ACS SUSTAINABLE CHEMISTRY & ENGINEERING 3 ( 4 ) 591 - 598 2015年4月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：AMER CHEMICAL SOC

Hydrothermal carbonization is considered to be an environment-friendly method to pretreat biomass. Therefore, hydrothermal carbonization of the husks of nuts from Carya cathayensis Sarg,, at various temperatures and pHs were performed and the fuel properties of the obtained residue, water-soluble products (WSP) and acetone-soluble products (ASP) were characterized. It was found that the residue yield decreased with increasing hydrothermal carbonization temperature while the yield of total soluble products (WSP and ASP) was nearly the same. The residue and total soluble products yields had no large changes in the pH range of 4.0-10.0, but fewer residues and more total soluble products were obtained at pH 13.0. It was confirmed that hemicellulose was more reactive than cellulose and lignin during hydrothermal carbonization and that lignin could be effectively hydrolyzed/decomposed at pH 13.0. The higher heating values (HHVs) of residues were in the ranges of 22.0 to 28.2 MJ kg(-1) at temperatures from 180 to 260 inverted perpendicular C and pH from 4.0 to 10.0. The HHVs of these residues could be comparable with those of some commercial coals, such as lignite. However, the HI-IVs of residues decreased when the pH reached to 13.0. The WSP and ASP showed lower HHVs compared with heavy fuel oils, which meant the HHVs of WSP and ASP should be increased before being applied as bio-fuels.

DOI： 10.1021/acssuschemeng.5b00103

Elevating the fuel properties of Humulus lupulus, Plumeria alba and Calophyllum inophyllum L. through wet torrefaction

Wei Yang, Toshinori Shimanouchi, Miki Iwamura, Yuki Takahashi, Ryota Mano, Kohei Takashima, Tatsuya Tanifuji, Yukitaka Kimura

FUEL 146 88 - 94 2015年4月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ELSEVIER SCI LTD

Wet torrefaction is an effective process to improve the fuel properties of a biomass. However, different biomasses have different component weight ratios and it is possible that not all biomasses are suitable for wet torrefaction treatment. Here we conducted wet torrefaction using three types of biomass with different component weight ratios: Humulus lupulus (HL, the common hop), Plumeria alba (PA, an evergreen shrub) and Calophyllum inophyllum L. (CIL, an evergreen tree). The fuel properties of the obtained solid fuels were characterized. We found that lignin made the main contribution to the solid fuel yield. The reactivity of cellulose and hemicellulose in each biomass was affected by the biomass species and the component weight ratio of the biomass. The wet torrefaction was observed to efficiently elevate the fuel properties of carbon content, atomic H/C and O/C ratios, higher heating value (HHV) and hydrophobicity of all three types of biomass. The HHVs of the solid fuels prepared at 260 degrees C are comparable to those of commercial coals such as Northumerland No. 81/2 Sem. Anth. Coal, Jhanjra Bonbahal Seam Coal-R-VII, and German Braunkohole lignite. These solid fuels could be co-combusted with German Braunkohole lignite without a significant change in the combustion properties of German Braunkohole lignite because of their similar atomic H/C and O/C ratios as well as HHVs. At the wet torrefaction temperature of 260 degrees C, the solid fuel delivered from CIL had lower HHV compared to those from HL and PA although CIL contained the highest lignin content, which has a higher HHV than those of cellulose and hemicellulose. Scanning electron microscopy images of the solid fuels revealed that wet torrefaction was able to completely destroy the biomass surface and create numerous pores and cracks on the solid fuels surface, indicating that the solid fuels have the potential to be used as a source of carbon materials such as activated carbon in addition to their use as bio-fuels. (C) 2015 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.fuel.2015.01.005

ToF-SIMS observation for evaluating the interaction between amyloid β and lipid membranes 国際誌

Satoka Aoyagi, Toshinori Shimanouchi, Tomoko Kawashima, Hideo Iwai

Analytical and Bioanalytical Chemistry 407 ( 10 ) 2859 - 63 2015年4月

記述言語：英語掲載種別：研究論文（学術雑誌）

© 2015 Springer-Verlag Berlin Heidelberg. Abstract The adsorption behaviour of amyloid beta (Aβ), thought to be a key peptide for understanding Alzheimer's disease, was investigated by means of time-of-flight secondary ion mass spectrometry (ToF-SIMS). Aβ aggregates depending on the lipid membrane condition though it has not been fully understood yet. In this study, Aβ samples on different lipid membranes, 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) and 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC), were observed with ToF-SIMS and the complex ToF-SIMS data of the Aβ samples was interpreted using data analysis techniques such as principal component analysis (PCA), gentle-SIMS (G-SIMS) and g-ogram. DOPC and DMPC are liquid crystal at room temperature, while DPPC is gel at room temperature. As primary ion beams, Bi<inf>3</inf><sup>+</sup> and Ar cluster ion beams were used and the effect of an Ar cluster ion for evaluating biomolecules was also studied. The secondary ion images of the peptide fragment ions indicated by G-SIMS and g-ogram were consistent with the PCA results. It is suggested that Aβ is adsorbed homogeneously on the liquid-crystalline-phase lipid membranes, while it aggregates along the lipid on the gel-phase lipid membrane. Moreover, in the results using the Ar cluster, the influence of contamination was reduced.

DOI： 10.1007/s00216-015-8527-3

Characterization of hydrochar prepared from hydrothermal carbonization of peels of Carya cathayensis sarg

Wei Yang, Toshinori Shimanouchi, Yukitaka Kimura

DESALINATION AND WATER TREATMENT 53 ( 10 ) 2831 - 2838 2015年3月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：DESALINATION PUBL

Hydrothermal carbonization of peels of Carya cathayensis sarg (PCCS) by subcritical water or acetone- and ethanol-modified subcritical water was carried out at the temperature from 280 to 360 degrees C and coal-like hydrochar was obtained. The hydrochar yield decreased with increasing of treatment temperature, but the higher heating value (HHV) and carbon content of hydrochar were promoted at higher treatment temperature. The HHV of hydrochar was in range of 30-46 MJ/kg with an increase from 52.4 to 127.6%, compared to the original PCCS. The HHVs of hydrochars obtained at 360 degrees C could be comparable with those of heavy fuel oil (42.9 MJ/kg) and diesel oil (45.7 MJ/kg). The O/C and H/C values of hydrochar were similar to those of lignite and subbituminous, except the ash content. Especially, the O/C and H/C values of hydrochars prepared at 360 degrees C could be compatible with those of bituminous. When treated with acetone- or ethanol-modified subcritical water, a synergistic effect of acetone-water or ethanol-water for hydrothermal carbonization was observed; the liquefaction rate with acetone-water or ethanol-water mixture was larger than that of water or acetone or ethanol only. There was no significant change on the O/C and H/C values and HHV on the hydrochar, although more PCCS, was decomposed when using acetone-water or ethanol-water mixture.

DOI： 10.1080/19443994.2014.931537

Target Protein Discrimination Based on Array Sensor Using Calcein-Encapsulating Liposomes with Cholesterol by Principal Component Analysis

R. Imamura, Z. Zhang, T. Yoshikawa, T. Shimanouchi, N. Murata, K. Yamashita, M. Fukuzawa, M. Noda

EUROSENSORS 2015 120 699 - 702 2015年

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）出版者・発行元：ELSEVIER SCIENCE BV

A bio array sensing system is newly composed utilizing different phospholipid liposomes encapsulating fluorescent molecules. We have confirmed a high output intensity of fluorescence emission due to the characteristics dependent on the concentration of fluorescent molecules when the fluorescent molecules leak from inside of the liposome through perturbed lipid membrane. After measuring a whole array image of fluorescence emission output from every element of liposome sensor by a new CMOS imager system, the outputs of fluorescence emission from all the elements were analyzed by a statistical method of principal component analysis (PCA). It was found from obtained PCA plots that different species of proteins with several concentrations were clearly discriminated with high cumulative contribution ratio. (C) 2015 Published by Elsevier Ltd.

DOI： 10.1016/j.proeng.2015.08.760

Discrimination of Target Proteins Using Arrayed Fluorescent Liposomes Incorporated with Cholesterol by Principal Component Analysis

R. Imamura, Z. Zhang, T. Yoshikawa, N. Murata, K. Yamashita, M. Fukuzawa, M. Noda, T. Shimanouchi

2015 IEEE SENSORS 1231 - 1234 2015年

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）出版者・発行元：IEEE

A bio array sensing system is newly composed utilizing different phospholipid liposomes encapsulating fluorescent molecules. We have confirmed a high output intensity of fluorescence emission due to the characteristics dependent on the concentration of fluorescent molecules when the fluorescent molecules leak from inside of the liposome through perturbed lipid membrane. After measuring a whole array image of fluorescence emission output from every element of liposome sensor by a new CMOS imager system, the outputs of fluorescence emission from all the elements were analyzed by a statistical method of principal component analysis (PCA). It was found from obtained PCA plots that different species of proteins with several concentrations were discriminated with high cumulative contribution ratio.

DOI： 10.1109/ICSENS.2015.7370493

Systematical characterization of phase behaviors and membrane properties of fatty acid/didecyldimethylammonium bromide vesicles. 国際誌

Keishi Suga, Tomoya Yokoi, Dai Kondo, Keita Hayashi, Seiichi Morita, Yukihiro Okamoto, Toshinori Shimanouchi, Hiroshi Umakoshi

Langmuir : the ACS journal of surfaces and colloids 30 ( 43 ) 12721 - 8 2014年11月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：AMER CHEMICAL SOC

Fatty acids (FAs) are known to form vesicle structures, depending on the surrounding pH conditions. In this study, we prepared vesicles by mixing FAs and a cationic surfactant, and then investigated their physicochemical properties using fluorescence spectroscopy and dielectric dispersion analysis (DDA). The assemblies formed from oleic acid (OA) and linoleic acid (LA) were modified by adding didecyldimethylammonium bromide (DDAB). The phase state of FA/DDAB mixtures was investigated with pH titration curves and turbidity measurements. The trigonal diagram of FA/ionized FA/DDAB was successfully drawn to understand the phase behaviors of FA/DDAB systems. The analysis of fluidities in the interior of the membrane with use of 1,6-diphenyl-1,3,5-hexatriene (DPH) indicated that the membrane fluidities of OA/DDAB and LA/DDAB at pH 8.5 slightly decreased in proportion to the molar ratio of DDAB in FA/DDAB systems. The fluorescent probe 6-lauroyl-2-dimethylamino naphthalene (Laurdan) indicated that the LA vesicle possessed a dehydrated surface, while the OA vesicle surface was hydrated. Modification of LA vesicles with DDAB induced the hydration of membrane surfaces, whereas modification of OA vesicles by DDAB had the opposite effect. DDA analysis indicated that the membrane surfaces were hydrated in the presence of DDAB, suggesting that the surface properties of FA vesicles are tunable by DDAB modification.

DOI： 10.1021/la503331r

Investigation of the Degradation Kinetic Parameters and Structure Changes of Microcrystalline Cellulose in Subcritical Water

Wei Yang, Toshinori Shimanouchi, Shengji Wu, Yukitaka Kimura

ENERGY & FUELS 28 ( 11 ) 6974 - 6980 2014年11月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：AMER CHEMICAL SOC

Cellulose is the most abundant nature polymer and the main component in all biomass. In this study, the degradation kinetic parameters and structure changes of microcrystalline cellulose (MCC), which served as fundamental studies for degradation of biomass in subcritical water, were investigated at the temperature range from 100 to 300 degrees C. The yield of the MCC residue began to decrease at 205 degrees C and reached the lowest value at 275 degrees C. However, it howed an increase at the temperature higher than 275 degrees C. The degradation area of MCC (205275 degrees C) was separated into zones 1 and 2 with 245 degrees C as a boundary. The activation energy (E), pre-exponential factor (A), and reaction order (n) of MCC in each zone were 226.5 kJ mol(-1), 2.3 x 10(23) s(-1), and 0.6 (zone 1) and 423.1 kJ mol(-1), 9.0 x 10(40) s(-1), and 0.5 (zone 2), respectively. There showed a breaking point of 245 degrees C for the Arrhenius plot in the reaction area. The surface morphology of the MCC residue had no significant change below 260 degrees C, as indicated by scanning electron microscopy (SEM) images. However, it was completely destroyed at the temperature above 275 degrees C, and MCC residues with strong pore structures were obtained at higher temperatures. The structures of the crystalline region of the MCC residue below 275 degrees C had no significant change, although 89.2% MCC was degraded at 275 degrees C. However, they nearly disappeared at higher temperatures with the steeply reducing crystallinity index of MCC at the same time. As for the degradation mechanism of MCC, it was proposed that only the surface of MCC was degraded at 205-245 degrees C and the hydrogen and glycosidic bonds on the interior of MCC fibrils were destroyed at the temperature range from 245 to 275 degrees C. Finally, the remaining MCC as well as generated oligomer and monomer were further degraded at higher temperatures.

DOI： 10.1021/ef501702q

Relationship between the mobility of phosphocholine headgroup and the protein-liposome interaction: a dielectric spectroscopic study. 国際誌

Toshinori Shimanouchi, Noriko Yoshimoto, Azusa Hiroiwa, Keiichi Nishiyama, Keita Hayashi, Hiroshi Umakoshi

Colloids and surfaces. B, Biointerfaces 116 343 - 50 2014年4月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ELSEVIER SCIENCE BV

Proteins could affect the headgroup mobility of phospholipid within liposome membranes through the protein-liposome interaction. The variation of headgroup mobility of phospholipid was then investigated by using the dielectric dispersion analysis. The eight proteins (Mw = 4.2-28.7 kDa) were used to investigate the protein-liposome interaction. It has been revealed that the strength of the protein-liposome interaction at 25 °C was linearly correlated with the stability of intramolecular hydrogen bondings of proteins, better than with their hydrophobicity and the surface charge density. Overall, liposomes composed of binary lipid system, appeared to strongly interact with proteins, in contrast to liposomes composed of single, ternary, and quaternary lipid systems. This is probably because liposomes composed of binary lipid system favored to form the microscopic environment where proteins could interact. The present result suggested the heterogeneous phase state of lipid membranes was one of dominant factors for the interaction between proteins and lipid membranes.

DOI： 10.1016/j.colsurfb.2013.07.028

Rapid Conversion of Glycerol to Lactic Acid under Alkaline Hydrothermal Conditions, by Using a Continuous Flow Reaction System

Toshinori Shimanouchi, Shouhei Ueno, Kazuki Shidahara, Yukitaka Kimura

CHEMISTRY LETTERS 43 ( 4 ) 535 - 537 2014年4月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：CHEMICAL SOC JAPAN

A rapid conversion of glycerol to lactic acid (lactate) could be successfully achieved under alkaline hydrothermal conditions, by using a continuous flow reaction system. A rapid conversion by a continuous flow-type reaction system made it possible to achieve the reaction under high-temperature conditions without side reactions. The rapid conversion and high reaction yield (reaction: 2 min; yield: 90%) resulted from the rapid temperature-shift advantageous for the inhibition of side reactions.

DOI： 10.1246/cl.131160

Extraction of reducing sugar with anti-oxidative scavengers from peels of Carya cathayensis sarg.: Use of subcritical water

Toshinori Shimanouchi, Shohei Ueno, Wei Yang, Yukitaka Kimura

Environmental Engineering Research 19 ( 1 ) 41 - 45 2014年3月

記述言語：英語掲載種別：研究論文（学術雑誌）

The peels of Carya cathayensis Sarg. (PCCS) were treated under subcritical water conditions (130°C to 280 °C for 0 to 120 min). The extract from PCCS included reducing sugar, proteins, and compounds with radical scavenging activity. Addressing the reducing sugar that is a resource of bioethanol, we could maximize the reducing sugar under the subcritical water (190°C for 60 min) and obtain 0.24 g/g-sample together with 9.7 units/mg-sample of radical scavenging activity. The obtained extract was estimated to correspond to 1 L of bioethanol/100 g-sample. It was therefore considered that the treatment by subcritical water could yield reducing sugar and natural compounds with radical scavenging activity. © 2014 Korean Society of Environmental Engineers.

DOI： 10.4491/eer.2014.19.1.041

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