研究者詳細 - 今村　維克

論文 - 今村　維克

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Pre-folding purification procedures for inclusion body-derived non-tagged cationic recombinant proteins with multiple disulfide bonds for efficient refolding. 国際誌

Shuichiro Kimura, Wataru Yamamoto, Ai Miyamoto, Koreyoshi Imamura, Junichiro Futami

Biotechnology progress e3532 2025年1月

記述言語：英語掲載種別：研究論文（学術雑誌）

The production of disulfide-containing recombinant proteins often requires refolding of inclusion bodies before purification. A pre-refolding purification step is crucial for effective refolding because impurities in the inclusion bodies interfere with refolding and subsequent purification. This study presents a new pre-refolding procedure using a reversible S-cationization technique for protein solubilization and purification by reversed-phase high performance liquid chromatography. This pre-folding purification step improves refolding yield by effectively removing the refolding inhibitors from contaminates from bacterial inclusion bodies, and reducing proteolytically degraded products. Because this procedure does not require a peptide tag for affinity purification, it is a superior technique to subsequently perform a simplified downstream process wherein the affinity tag needs to be removed. This study reports improved refolding and purification procedure to obtain the highly cationic (pI = 9.25) mouse vascular endothelial cell growth factor (188 amino acids form) that is used as a model protein in our study; this protein shows a homodimeric conformation and possesses multiple disulfides.

DOI： 10.1002/btpr.3532

PubMed

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噴霧乾燥および保存時におけるアモルファス固体分散中の疎水性薬剤の結晶化阻害に関する研究査読

Yamamoto, Rina, Imanaka, H, Ishida, Naoyuki, Imamura, Koreyoshi

Drying Technology 42 ( 13 ) 2022 - 2031 2024年11月

種々の条件における真空foam乾燥および噴霧乾燥によって調製したアモルファス固体分散体の香料保持特性査読

Nitta, Yuna, Sato, H, Yamamoto, Rina, Imanaka, Hiroyuki, Ishida, Naoyuki, Imamura, K

42 ( 2 ) 227 - 237 2024年1月

Water sorption and glass-to-rubber transition of amorphous sugar matrices, vacuum foam- and spray-dried from alcohols 査読

Koji Takeda, Shinta Miyazaki, Takashi Okamoto, Hiroyuki Imanaka, Naoyuki Ishida, Koreyoshi Imamura

JOURNAL OF FOOD ENGINEERING 349 2023年7月

担当区分：最終著者,　責任著者記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ELSEVIER SCI LTD

The objective of this study is to understand the impact of preparation conditions on the physicochemical characteristics of amorphous sugar. Amorphous sugar (alpha-maltose, isomaltulose, trehalose) matrices were pre -pared from alcohol (methanol, ethanol) solutions, and their water sorption behavior and glass transition tem-peratures, Tg, were compared with those of aqueous freeze-dried amorphous sugar. Vacuum-foam-and spray -drying procedures were employed as drying methods. Water sorption for amorphous sugars, dried by different methods, was generally significant in the following order: vacuum-foam-drying < spray-drying <= freeze-drying. In the same order, the Tg values for the thoroughly dried amorphous sugars increased, and water sorption reduced the differences in Tg for given amounts of sorbed water. The solvent type in vacuum-foam-drying slightly affected the water sorption and the dependence of Tg on the sorbed water amount. The obtained findings sug-gested that physicochemical characteristics of amorphous sugar may relate to the sugar molecule conformations in solvent and dried state.

添付ファイル： JFOODENG-D-22-02113_R3-3.pdf

DOI： 10.1016/j.jfoodeng.2023.111483

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Evaluation of interaction forces between hydrophobic surfaces in surfactant solutions by atomic force microscopy 査読

Shota Kage, Koreyoshi Imamura, Naoyuki Ishida

Colloid and Polymer Science 301 ( 7 ) 775 - 782 2023年7月

掲載種別：研究論文（学術雑誌）

The interaction forces between silica surfaces with various degrees of hydrophobicity were measured using colloidal probe atomic force microscopy to clarify the relationship between the hydrophobicity of the surfaces and hydrophobic attraction in detail. The interaction forces between silica surfaces pre-hydrophobised with octadecyltrichlorosilane were measured in aqueous solutions with three different (cationic, anionic, and nonionic) surfactants. Hydrophobic attraction was observed between surfaces from 10 to 15 nm without surfactant, and the range of this attraction decreased when the surface hydrophobicity decreased with increasing surfactant concentration. The hydrophobic attraction disappeared when the surface contact angle was below 80°–90° in the presence of all surfactants used in this study. The range of the hydrophobic attraction was found to depend strongly on the contact angle and not on the surfactant type and concentration. The adhesion force was also highly dependent on the contact angle and comparable to the theoretical capillary force. The possible origin of this force is discussed with reference to the obtained results. Graphical Abstract: [Figure not available: see fulltext.].

DOI： 10.1007/s00396-023-05118-w

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Evaluation of Hydrophobic Attraction between Polystyrene Layer and Silanated Silica Surface by Atomic Force Microscopy 査読

Yuta Okuda, Koreyoshi Imamura, Naoyuki Ishida

Chemistry Letters 52 ( 12 ) 878 - 882 2023年

掲載種別：研究論文（学術雑誌）

In this study, hydrophobic surfaces were prepared by depositing polystyrene (PS) on a glass substrate using three different methods to measure the interaction forces against a hydrophobized particle by atomic force microscopy. We found that smooth surfaces prepared by spin coating and living radical polymerization generated hydrophobic attraction, whereas uneven surfaces obtained by free radical polymerization produced only steric repulsion, even though they had sufficient hydrophobicity. Based on these results, the origin of the hydrophobic attraction was suggested.

DOI： 10.1246/cl.230363

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Kinetics of Enzymatic Reactions at the Solid/Liquid Interface in Nanofluidic Channels 査読

Koki Yamamoto, Kyojiro Morikawa, Hiroyuki Imanaka, Koreyoshi Imamura, Takehiko Kitamori

Analytical Chemistry 2022年10月

Extraordinary high preservation of the dispersion state of Au nanoparticles during freeze-thawing and freeze-drying with gum arabic 査読

Miki Kadowaki, Tsutashi Matsuura, Hiroyuki Imanaka, Naoyuki Ishida, Koreyoshi Imamura

Colloids and Surfaces A: Physicochemical and Engineering Aspects 639 2022年4月

担当区分：最終著者,　責任著者記述言語：英語掲載種別：研究論文（学術雑誌）

A series of edible and non-toxic substances were screened for their ability to prevent Au nanoparticles (AuNPs) from undergoing aggregation during both freeze-thawing and freeze-drying at as low an additive concentration as possible. Gum arabic was found to be an ideal choice. The addition of 20 µg/mL of gum arabic greatly inhibited the aggregation of AuNPs during freeze-thawing and -drying, whereas polyvinylpyrrolidone was the next best among the tested substances, with approximately 20% aggregation during freeze-drying at a concentration of less than 200 µg/mL. The zeta potential value of the AuNPs indicated the absence of the specific binding of gum arabic to the AuNPs surface. Surface enhanced infrared spectroscopic (SEIRAS) analyses were conducted for the gum arabic solution, frozen and freeze-dried on the Au particles. The results indicated that, in the frozen state, gum arabic molecules were concentrated in remaining unfrozen liquid on the Au coating without any specific orientation toward the Au surface. In contrast, SEIRAS spectra of freeze-dried gum arabic indicated that carboxylic groups in gum arabic molecules preferentially became closer to the Au surface. Considering these findings, during freeze-thawing, we conclude that the high thickening property of gum arabic gum plays an important role in minimizing the mobility and thus the aggregation of AuNPs in the freeze-concentrated regions between frozen ice crystals. The freeze-drying of a gum arabic solution produces a rigid amorphous matrix that has an affinity for the Au surface. The AuNPs were individually separated and immobilized in the freeze-dried matrix of the gum arabic, resulting in the extraordinary inhibition of their aggregation.

添付ファイル： COLSUA_128392_edit_report.pdf

DOI： 10.1016/j.colsurfa.2022.128392

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Comparison of improvements of aqueous dissolution of structurally analogous hydrophobic drugs by amorphous solid dispersion 招待査読

Takashi Okamoto, Kayoko Yamamoto, Takanari Sekitoh, Akiho Fujioka, Hiroyuki Imanaka, Naoyuki Ishida, Koreyoshi Imamura

Colloids and Surfaces A: Physicochemical and Engineering Aspects 632 127744 - 127744 2022年1月

Induction of foaming in vacuum drying by needle stimulation and the impact of solution viscosity, vapor pressure, and the type of solute and solvent 査読

Akiho Fujioka, Rina Yamamoto, Olivier Tramis, Hiroaki Ishida, Tsutomu Ono, Naoyuki Ishida, Koreyoshi Imamura

Drying Technology 1 - 13 2021年12月

Foaming characteristics of sugar- and polyvinylpyrrolidone-alcohol solutions during vacuum foam drying: A rheological approach 査読

Olivier Tramis, Akiho Fujioka, Hiroyuki Imanaka, Naoyuki Ishida, Koreyoshi Imamura

Colloids and Surfaces A: Physicochemical and Engineering Aspects 627 127174 - 127174 2021年10月

担当区分：最終著者記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Elsevier BV

Vacuum foam drying offers great perspectives to formulate solid-state encapsulated active drugs. Taking into account the specific need of pharmaceutical formulations to keep drug molecules active and dispersed, we show in this paper that vacuum drying of pharmaceutical formulations can be substantially improved by using original rheological approaches. Typically, our formulations totally dried-up in less than 5 min, a delay much shorter than the long hours of the traditional vacuum drying process. Steady-shear rheology was used to evaluate the solution's specific viscosity against the solutions' concentrations, in order to correlate the dilution regime to the foamabiltiy. This rheological approach indicated that in miscible solutions, spontaneous foaming occurred in the semi-dilute entangled regime, near the transition to the concentrated regime; for partially miscible solutions, it occurred in solutions at a concentration near to the percolation concentration. The proposed methodology is versatile, and should provide a simple way to assess the foamability of pharmaceutical formulations.

添付ファイル： P0NeedleTramis2-pub.pdf

DOI： 10.1016/j.colsurfa.2021.127174

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Inhibiting Au nanoparticle aggregation in freeze-thawing by presence of various additives 査読

Miki Kadowaki, Hidetaka Yokota, Hiroyuki Imanaka, Naoyuki Ishida, Koreyoshi Imamura

Advanced Powder Technology 32 ( 10 ) 3517 - 3524 2021年10月

Direct measurements of interaction forces of bovine serum albumin and lysozyme with stainless steel by atomic force microscopy 査読

Hikaru Kawaguchi, Hiroyuki Imanaka, Koreyoshi Imamura, Naoyuki Ishida

Colloids and Surfaces A: Physicochemical and Engineering Aspects 627 127137 - 127137 2021年10月

Sole-amorphous-sugar-based solid dispersion of curcumin and the influence of formulation composition and heat treatment on the dissolution of curcumin 査読

Takanari Sekitoh, Takashi Okamoto, Akiho Fujioka, Olivier Tramis, Koji Takeda, Tsutashi Matsuura, Hiroyuki Imanaka, Naoyuki Ishida, Koreyoshi Imamura

Drying Technology 39 ( 14 ) 2065 - 2074 2021年9月

担当区分：最終著者,　責任著者記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Informa UK Limited

An amorphous solid dispersion technique, in which hydrophobic drug molecules are dispersed in an amorphous matrix comprised solely of a sugar, was applied to curcumin that has excellent physiological functions. The sole-amorphous-sugar-based solid dispersion (SAS-SD) of curcumin was prepared by vacuum foam drying from methanol, using various disaccharides as the drug carrier-forming component. Aqueous dissolution of curcumin from the SAS-SD showed “spring-and-parachute” shape profile and was markedly increased when a sugar (α-maltose or trehalose) was added in a composition range ≥100 g-sugar/g-curcumin. Further dissolution was achieved by heating the SAS-SD at close to and above the melting points of curcumin.

添付ファイル： P0SF-Cur-draft.pdf

DOI： 10.1080/07373937.2020.1752711

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アルコールから乾燥調製したトレハロースアモルファスの結晶化特性査読

関藤孝成, 岡本崇, 藤岡亜希穂, 吉岡朋彦, 照井真司, 今中洋行, 石田尚之, 今村維克

292 110325 - 110325 2021年3月

Direct measurement of interaction force between hydrophilic silica surfaces in triblock copolymer solutions with salt by atomic force microscopy 査読

Takumi Deguchi, Takato Nakahara, Koreyoshi Imamura, Naoyuki Ishida

Advanced Powder Technology 32 ( 1 ) 30 - 36 2021年1月

ポリビニルピロリドンおよび糖のアルコール溶液の真空乾燥における自発的な発泡と難水溶性薬物の対水溶解性の改善査読

Olivier Tramis,藤岡亜希穂,今中洋行,石田尚之,今村維克

1 - 11 2020年9月

食品タンパク質をはじめとする生体分子の包括安定化技術に関する工学研究招待査読

今村維克

日本食品工学会誌 21 ( 3 ) 95 - 111 2020年9月

A suitable and effective stepwise oxidative refolding procedure for highly‐cationic tetrameric avidin in nucleic acid free conditions 査読国際誌

Shuichiro Kimura, Koreyoshi Imamura, Junichiro Futami

Biotechnology Progress 36 ( 5 ) e3031 2020年9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

Optimized conditions are needed to refold recombinant proteins from bacterial inclusion bodies into their biologically active conformations. In this study, we found two crucial requirements for efficient refolding of cationic tetrameric chicken avidin. The first step is to eliminate nucleic acid contaminants from the bacterial inclusion body. The electrostatic interactions between the remaining nucleic acids and proteins strongly enhanced protein aggregation during the refolding process. The cysteine specific reversible S-cationization procedure was successfully employed for large-scale preparation of nucleic acid free denatured protein without purification tag system. The second step is the intramolecular disulfide formation prior to refolding in dialysis removing denaturant. Disulfide intact monomeric avidin showed efficient formation of biologically active tetrameric conformation during the refolding process. Using this optimized refolding procedure, highly cationic avidin derivative designed as an intracellular delivery carrier of biotinylated protein was successfully prepared.

DOI： 10.1002/btpr.3031

PubMed

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その他リンク： https://onlinelibrary.wiley.com/doi/full-xml/10.1002/btpr.3031

糖および界面活性剤複合系による金ナノ粒子の凍結乾燥における分散安定化査読

横田秀隆, 門脇美季, 松浦傳史, 今中洋行, 石田尚之, 今村維克

36 ( 24 ) 6698 - 6705 2020年6月