Researcher Profile and Settings

Master

Affiliation (Master)

• Faculty of Fisheries Sciences　Marine Life Science　Marine Chemical Resource Development

Affiliation (Master)

• Faculty of Fisheries Sciences　Marine Life Science　Marine Chemical Resource Development

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Profile and Settings

Profile and Settings

• Name (Japanese)

  Kumagai

• Name (Kana)

  Yuya

• Name

  201301024085045609

Achievement

Research Interests

• タンパク質工学   酵素利用   紅藻類   

Research Areas

• Life sciences / Marine/Aquatic life sciences

Research Experience

• 2022/04 - Today Hokkaido Universiy Faculty of Fisheries Sciences Division of Marine Life Science
• 2018 - 2022/03 Hokkaido University Faculty of Fisheries Science Assistant Professor

Education

• 2005/04 - 2010/03  Hokkaido University  Graduate School of Fisheries Sciences  Division of Marine Life Science
• 2001/04 - 2005/03  Hokkaido University  School of Fisheries Sciences  Department of Marine Bioresources Chemistry

Committee Memberships

• 2021/01 - Today   Phycology (ISSN: 2673-9410)   Editorial Board
• 2021/12 -2023/01   Guest Editor of the Special Issue "Advances in Oligosaccharides and Polysaccharide Modifications in Marine Bioresources"   Marine Drugs

Awards

• 2024/09 公益社団法人日本缶詰びん詰レトルト食品協会 令和 6 年度年度「逸見賞」
   海藻レトルト食品の栄養成分および抗酸化 力に及ぼす製造条件の影響 

  受賞者: 宮部好克;落合瞳子;熊谷祐也;岸村栄毅
• 2022/11 キャンパス・コンソーシアム函館 ブースセッション『優秀賞』
   色落ちダルスに救済を! 

  受賞者: 濵﨑海瑠;辰巳 幸彦;岸村栄毅;熊谷祐也
• 2021/12 キャンパス・コンソーシアム函館 ブースセッション『大賞』
   海藻のヌメヌメ成分「フコイダン」の最大Maxパワー力を生かすために 

  受賞者: 松井亘;伊藤大翔;熊谷祐也;岸村栄毅
• 2021/12 キャンパス・コンソーシアム函館 ステージセッション『優秀賞 (産学連携「クリエイティブネットワーク」賞) 』
   季節変動から紐解くダルス「MAAs」産業利用への試み 

  受賞者: 前田侑也;山本竜矢;熊谷祐也;岸村栄毅
• 2020/11 キャンパス・コンソーシアム函館 ブースセッション『優秀賞』
   ダルスで腸を元気にする！ 

  受賞者: 吉田光里;小林真奈美;栗田大輝;熊谷祐也;岸村栄毅
• 2020/11 キャンパス・コンソーシアム函館 ブースセッション『優秀賞』
   ミッション！低利用海藻に眠るお宝「MAAs」を可能な限り手に入れよ！ 

  受賞者: 杉山佳奈海;西田有輝;熊谷祐也;岸村栄毅
• 2020/11 Food Society of Modern International Lifestyle Education Good Oral Award
   Efficient Extraction and Monthly Variation of Mycosporine-like Amino Acids from Red Alga Dulse in Japan 

  受賞者: ○Yuki Nishida;Yuya Kumagai;Shunta Michiba;Hajime Yasui;Hideki Kishimura
• 2019/11 キャンパス・コンソーシアム函館「アカデミックリンク2019」大賞 海藻の秘密兵器！？「マイコスポリン様アミノ酸」
   

  受賞者: 西田有輝;熊谷祐也;岸村英毅
• 2018/11 キャンパス・コンソーシアム函館 ブース部門『優秀賞』「絶対に捨てられない海藻がここにある」
   

  受賞者: 小林真奈美;山本陽平;熊谷祐也;岸村栄毅
• 2013/09 日本応用糖質科学 日本応用糖質科学会平成25年度大会（第62回）ポスター賞
   Gluconobacter oxydans由来dextran dextrinaseによる直鎖イソマルトメガロ糖の酵素合成 

  受賞者: 熊谷祐也;Weeranuch Lang;貞廣樹里;奥山正幸;森 春英;木村淳夫
• 2012/02 日本応用糖質科学北海道支部 平成23年度日本応用糖質学会北海道支部・支部奨励賞
   水産軟体動物由来ラミナリナーゼの酵素特性と環境適応に関する研究 

  受賞者: 熊谷祐也

Published Papers

• Molecular structure of enzyme-synthesized amylose-like chimeric isomaltomegalosaccharides and their encapsulation of the sulfasalazine prodrug

  Weeranuch Lang, Yoshiaki Yuguchi, Chun-Yao Ke, Ting-Wei Chang, Yuya Kumagai, Wilaiwan Kaenying, Takayoshi Tagami, Feng Li, Takuya Yamamoto, Kenji Tajima, Kenji Takahashi, Takuya Isono, Toshifumi Satoh, Atsuo Kimura

  Carbohydrate Polymers 122956 - 122956 0144-8617 2024/11 [Refereed][Not invited]
  
• Extraction and antioxidant capacity of mycosporine-like amino acids from red algae in Japan.

  Ryuya Yamamoto, Shigeru Toriumi, Chikara Kawagoe, Wataru Saburi, Hideki Kishimura, Yuya Kumagai

  Bioscience, biotechnology, and biochemistry 2024/04/29 [Refereed][Not invited]
   

  Mycosporine-like amino acids (MAAs) are the natural UV absorbing compounds with antioxidant activity found in microalgae and macroalgae. We collected red algae Asparagopsis taxiformis, Meristotheca japonica, and Polysiphonia senticulosa from Nagasaki, where UV radiation is more intense than in Hokkaido, and investigated the effect of UV radiation on MAAs content. It was suggested that A. taxiformis and M. japonica contained shinorine and palythine, while UV absorbing compound in P. senticulosa could not be identified. The amounts of these MAAs were lower compared to those from Hokkaido. Despite an increase in UV radiation in both region from February to April, MAAs contents of red algae from Nagasaki slightly decreased, while that from Hokkaido significantly decreased. This difference was suggested the amount of inorganic nitrogen in the ocean. Antioxidant activity of MAAs increased under alkaline conditions. The extract containing MAAs from P. senticulosa showed the highest antioxidant activity among four red algae.
• Understanding Antidiabetic Potential of Oligosaccharides from Red Alga Dulse Devaleraea inkyuleei Xylan by Investigating α-Amylase and α-Glucosidase Inhibition

  Martin Alain Mune Mune, Tadashi Hatanaka, Hideki Kishimura, Yuya Kumagai

  Molecules 29 (7) 1536 - 1536 2024/03/29 [Refereed][Not invited]
   

  In this study, the α-glucosidase (maltase-glucoamylase: MGAM) and α-amylase inhibitory properties elicited by xylooligosaccharides (XOSs) prepared from dulse xylan were analysed as a potential mechanism to control postprandial hyperglycaemia for type-2 diabetes prevention and treatment. Xylan was purified from red alga dulse powder and used for enzymatic hydrolysis using Sucrase X to produce XOSs. Fractionation of XOSs produced xylobiose (X2), β-(1→3)-xylosyl xylobiose (DX3), xylotriose (X3), β-(1→3)-xylosyl-xylotriose (DX4), and a dulse XOS mixture with n ≥ 4 xylose units (DXM). The different fractions exhibited moderate MGAM (IC50 = 11.41–23.44 mg/mL) and α-amylase (IC50 = 18.07–53.04 mg/mL) inhibitory activity, which was lower than that of acarbose. Kinetics studies revealed that XOSs bound to the active site of carbohydrate digestive enzymes, limiting access to the substrate by competitive inhibition. A molecular docking analysis of XOSs with MGAM and α-amylase clearly showed moderate strength of interactions, both hydrogen bonds and non-bonded contacts, at the active site of the enzymes. Overall, XOSs from dulse could prevent postprandial hyperglycaemia as functional food by a usual and continuous consumption.
• Tunable structure of chimeric isomaltomegalosaccharides with double α-(1 → 4)-glucosyl chains enhances the solubility of water-insoluble bioactive compounds

  Weeranuch Lang, Takayoshi Tagami, Yuya Kumagai, Seiya Tanaka, Hye-Jin Kang, Masayuki Okuyama, Wataru Saburi, Haruhide Mori, Tohru Hira, Chaehun Lee, Takuya Isono, Toshifumi Satoh, Hiroshi Hara, Takayuki Kurokawa, Nobuo Sakairi, Yoshiaki Yuguchi, Atsuo Kimura

  Carbohydrate Polymers 319 121185 - 121185 0144-8617 2023/11 [Refereed][Not invited]
  
• Mycosporine-like Amino Acids from Red Alga Dulse (Devaleraea inkyuleei): Monthly Variation and Improvement in Extraction

  Ryuya Yamamoto, Koki Takizawa, Yoshikatsu Miyabe, Martin Alain Mune Mune, Hideki Kishimura, Yuya Kumagai

  Phycology 3 (3) 394 - 404 2023/09/07 [Refereed][Not invited]
   

  Mycosporine-like amino acids (MAAs) are natural UV-absorbing compounds found in microalgae and macroalgae. The content of MAAs in algae varies with the seasons and environmental factors. Red alga dulse in Usujiri (Hokkaido, Japan) is an underutilized resource. Therefore, we investigated the amount of MAAs in Usujiri dulse in 2022 to clarify the suitable months for MAA extraction. In addition, we also evaluated the extraction method focusing on the extraction volume. MAAs were prepared via the 20 volumes of 25% ethanol extraction method and detected via HPLC. The results showed that the amount of MAAs on 25 March 2022 showed the highest value (40.4 μmol/g DW) among the samples from 24 January to 13 May. The tendency of suitable samples for MAA preparation corresponded to the term from mid-February to early April, which was the same as the previous three years. Although the surveys from 2019–2021 were performed by using the successive water–methanol method, it was found that the improved method also reflected the monthly variation in MAAs. The extraction of MAAs was performed via 20 or 40 volumes of 25% ethanol at 4 °C for 24 h. The amount of MAAs with 40 volumes of 25% ethanol extraction increased 1.3-fold compared to that with 20 volumes of 25% ethanol extraction. These data are useful information for valuable compound extraction from Usujiri dulse.
• 海藻レトルト食品の栄養成分および抗酸化力に及ぼす製造条件の影響

  宮部好克, 落合瞳子, 熊谷祐也, 岸村栄毅

  日本調理科学会誌 2023/06 [Refereed]
  
• Exploring Bioactive Compounds in Brown Seaweeds Using Subcritical Water: A Comprehensive Analysis

  Jin-Seok Park, Ji-Min Han, Yu-Na Shin, Ye-Seul Park, Ye-Ryeon Shin, Sin-Won Park, Vikash Chandra Roy, Hee-Jeong Lee, Yuya Kumagai, Hideki Kishimura, Byung-Soo Chun

  Marine Drugs 21 (6) 328 - 328 2023/05/26 

  In this study, we characterized the bioactive properties of three important brown seaweed species, Sargassum thunbergii, Undaria pinnatifida, and Saccharina japonica, by subcritical water extraction (SWE), as these species are well known for their beneficial health effects. Their physiochemical properties, including potential antioxidant, antihypertensive, and α-glucosidase inhibitory activity, and the antibacterial activity of the hydroysates were also analyzed. The highest total phlorotannin, total sugar content, and reducing sugar content in the S. thunbergii hydrolysates were 38.82 ± 0.17 mg PGE/g, 116.66 ± 0.19 mg glucose/g dry sample, and 53.27 ± 1.57 mg glucose/g dry sample, respectively. The highest ABTS+ and DPPH antioxidant activities were obtained in the S. japonica hydrolysates (124.77 ± 2.47 and 46.35 ± 0.01 mg Trolox equivalent/g, respectively) and the highest FRAP activity was obtained in the S. thunbergii hydrolysates (34.47 ± 0.49 mg Trolox equivalent/g seaweed). In addition, the seaweed extracts showed antihypertensive (≤59.77 ± 0.14%) and α-glucosidase inhibitory activity (≤68.05 ± 1.15%), as well as activity against foodborne pathogens. The present findings provide evidence of the biological activity of brown seaweed extracts for potential application in the food, pharmaceutical, and cosmetic sectors.
• Monthly Variation in Mycosporine-like Amino Acids from Red Alga Dulse (Devaleraea inkyuleei, Formerly Palmaria palmata in Japan)

  Ryuya Yamamoto, Martin Alain Mune Mune, Yoshikatsu Miyabe, Hideki Kishimura, Yuya Kumagai

  Phycology 3 (1) 127 - 137 2023/02/09 [Refereed]
   

  Mycosporine-like amino acids (MAAs) are natural ultraviolet-absorbing compounds found in microalgae and macroalgae. MAA content changes seasonally and in response to environmental factors. We previously investigated MAAs from the red alga dulse (Devaleraea inkyuleei, formerly Palmaria palmata in Japan) in Usujiri, Hokkaido, Japan, from 2019 to 2020. At that time, some factors affecting MAA content were still unclear. In this study, we investigated MAA variation during the period from January to June 2021, and evaluated new methods of MAA extraction from dulse. We recorded a maximum MAA extraction yield (7.03 µmol/g dry weight) on 25 March 2021. Over the course of our three years of investigations from 2019 to 2021, we found that dulse was most suitable for MAA preparation from the middle of February to late April. In the later work reported in this paper, we improved our extraction method by using a lower-risk organic solvent (ethanol) rather than methanol. In addition, we evaluated MAA extraction using different levels of ethanol concentration (25, 50, and 99%) and different extraction times (2, 6, and 24 h). We found that extraction with 25% ethanol for 24 h increased MAA content by a factor of 3.2, compared with our previous extraction method. In summary, we determined the most suitable sampling period for Usujiri dulse, to extract the highest content of MAAs. We also improved the effectiveness of the extraction process.
• Characterisation of Bioactive Peptides from Red Alga Gracilariopsis chorda

  Martin Alain Mune Mune, Yoshikatsu Miyabe, Takeshi Shimizu, Wataru Matsui, Yuya Kumagai, Hideki Kishimura

  Marine Drugs 21 (1) 49 - 49 2023/01/11 [Refereed]
   

  In this study, we studied the bioactive peptides produced by thermolysin hydrolysis of a water-soluble protein (WSP) from the red alga Gracilariopsis chorda, whose major components are phycobiliproteins and Ribulose-1,5-bisphosphate carboxylase-oxygenase (RuBisCo). The results showed that WSP hydrolysate exhibited significantly higher ACE inhibitory activity (92% inhibition) compared to DPP-IV inhibitory activity and DPPH scavenging activity. The phycobiliproteins and RuBisCo of G. chorda contain a high proportion of hydrophobic (31.0–46.5%) and aromatic (5.1–46.5%) amino acid residues, which was considered suitable for the formation of peptides with strong ACE inhibitory activity. Therefore, we searched for peptides with strong ACE inhibitory activity and identified two novel peptides (IDHY and LVVER). Then, their interaction with human ACE was evaluated by molecular docking, and IDHY was found to be a promising inhibitor. In silico analysis was then performed on the structural factors affecting ACE inhibitory peptide release, using the predicted 3D structures of phycobiliproteins and RuBisCo. The results showed that most of the ACE inhibitory peptides are located in the highly solvent accessible α-helix. Therefore, it was suggested that G. chorda is a good source of bioactive peptides, especially ACE-inhibitory peptides.
• Editorial: Application of biotechnology on the high-value development of marine bioresource

  Zedong Jiang, Haijin Mou, Yuya Kumagai, Hideki Kishimura

  Frontiers in Bioengineering and Biotechnology 10 2022/10 [Not refereed]
  
• Physicochemical functionality of chimeric isomaltomegalosaccharides with α-(1 → 4)-glucosidic segments of various lengths

  Weeranuch Lang, Yuya Kumagai, Shinji Habu, Juri Sadahiro, Takayoshi Tagami, Masayuki Okuyama, Shinichi Kitamura, Nobuo Sakairi, Atsuo Kimura

  Carbohydrate Polymers 291 119562 - 119562 0144-8617 2022/09 [Refereed][Not invited]
  
• Characterization of an Unknown Region Linked to the Glycoside Hydrolase Family 17 β-1,3-Glucanase of Vibrio vulnificus Reveals a Novel Glucan-Binding Domain.

  Yuya Kumagai, Hideki Kishimura, Weeranuch Lang, Takayoshi Tagami, Masayuki Okuyama, Atsuo Kimura

  Marine drugs 20 (4) 2022/03/31 [Refereed][Not invited]
   

  The glycoside hydrolase family 17 β-1,3-glucanase of Vibrio vulnificus (VvGH17) has two unknown regions in the N- and C-termini. Here, we characterized these domains by preparing mutant enzymes. VvGH17 demonstrated hydrolytic activity of β-(1→3)-glucan, mainly producing laminaribiose, but not of β-(1→3)/β-(1→4)-glucan. The C-terminal-truncated mutants (ΔC466 and ΔC441) showed decreased activity, approximately one-third of that of the WT, and ΔC415 lost almost all activity. An analysis using affinity gel containing laminarin or barley β-glucan revealed a shift in the mobility of the ΔC466, ΔC441, and ΔC415 mutants compared to the WT. Tryptophan residues showed a strong affinity for carbohydrates. Three of four point-mutations of the tryptophan in the C-terminus (W472A, W499A, and W542A) showed a reduction in binding ability to laminarin and barley β-glucan. The C-terminus was predicted to have a β-sandwich structure, and three tryptophan residues (Trp472, Trp499, and Trp542) constituted a putative substrate-binding cave. Linker and substrate-binding functions were assigned to the C-terminus. The N-terminal-truncated mutants also showed decreased activity. The WT formed a trimer, while the N-terminal truncations formed monomers, indicating that the N-terminus contributed to the multimeric form of VvGH17. The results of this study are useful for understanding the structure and the function of GH17 β-1,3-glucanases.
• Introduction of a second "Green Revolution" mutation into wheat via in planta CRISPR/Cas9 delivery.

  Yuya Kumagai, Yuelin Liu, Haruyasu Hamada, Weifeng Luo, Jianghui Zhu, Misa Kuroki, Yozo Nagira, Naoaki Taoka, Etsuko Katoh, Ryozo Imai

  Plant physiology 188 (4) 1838 - 1842 2022/03/28 [Refereed][Not invited]
   

  Direct delivery of CRISPR/Cas9 ribonucleoproteins into the shoot apical meristem via particle bombardment enabled introduction of a semidwarf1-orthologous mutation into an elite wheat variety.
• Characterization of Antioxidant Activity of Heated Mycosporine-like Amino Acids from Red Alga Dulse Palmaria palmata in Japan.

  Yuki Nishida, Wataru Saburi, Yoshikatsu Miyabe, Hideki Kishimura, Yuya Kumagai

  Marine drugs 20 (3) 2022/03/01 [Refereed][Not invited]
   

  We recently demonstrated the monthly variation and antioxidant activity of mycosporine-like amino acids (MAAs) from red alga dulse in Japan. The antioxidant activity of MAAs in acidic conditions was low compared to that in neutral and alkali conditions, but we found strong antioxidant activity from the heated crude MAA fraction in acidic conditions. In this study, we identified and characterized the key compounds involved in the antioxidant activity of this fraction. We first isolated two MAAs, palythine, and porphyra-334, from the fraction and evaluated the activities of the two MAAs when heated. MAAs possess absorption maxima at around 330 nm, while the heated MAAs lost this absorption. The heated MAAs showed a high ABTS radical scavenging activity at pH 5.8-8.0. We then determined the structure of heated palythine via ESI-MS and NMR analyses and speculated about the putative antioxidant mechanism. Finally, a suitable production condition of the heated compounds was determined at 120 °C for 30 min at pH 8.0. We revealed compounds from red algae with antioxidant activities at a wide range of pH values, and this information will be useful for the functional processing of food.
• Physicochemical properties of house and cave edible bird's nest from Southern Thailand

  Kasidate Chantakun, Hideki Kishimura, Yuya Kumagai, Soottawat Benjakul

  ScienceAsia 48 (2) 136 - 136 1513-1874 2022/02 [Refereed][Not invited]
  
• A practical approach to producing isomaltomegalosaccharide using dextran dextrinase from Gluconobacter oxydans ATCC 11894.

  Weeranuch Lang, Yuya Kumagai, Juri Sadahiro, Wataru Saburi, Rakrudee Sarnthima, Takayoshi Tagami, Masayuki Okuyama, Haruhide Mori, Nobuo Sakairi, Doman Kim, Atsuo Kimura

  Applied microbiology and biotechnology 106 (2) 689 - 698 2022/01 [Refereed][Not invited]
   

  Dextran dextrinase (DDase) catalyzes formation of the polysaccharide dextran from maltodextrin. During the synthesis of dextran, DDase also generates the beneficial material isomaltomegalosaccharide (IMS). The term megalosaccharide is used for a saccharide having DP = 10-100 or 10-200 (DP, degree of polymerization). IMS is a chimeric glucosaccharide comprising α-(1 → 6)- and α-(1 → 4)-linked portions at the nonreducing and reducing ends, respectively, in which the α-(1 → 4)-glucosyl portion originates from maltodextrin of the substrate. In this study, IMS was produced by a practical approach using extracellular DDase (DDext) or cell surface DDase (DDsur) of Gluconobacter oxydans ATCC 11894. DDsur was the original form, so we prepared DDext via secretion from intact cells by incubating with 0.5% G6/G7 (maltohexaose/maltoheptaose); this was followed by generation of IMS from various concentrations of G6/G7 substrate at different temperatures for 96 h. However, IMS synthesis by DDext was limited by insufficient formation of α-(1 → 6)-glucosidic linkages, suggesting that DDase also catalyzes elongation of α-(1 → 4)-glucosyl chain. For production of IMS using DDsur, intact cells bearing DDsur were directly incubated with 20% G6/G7 at 45 °C by optimizing conditions such as cell concentration and agitation efficiency, which resulted in generation of IMS (average DP = 14.7) with 61% α-(1 → 6)-glucosyl content in 51% yield. Increases in substrate concentration and agitation efficiency were found to decrease dextran formation and increase IMS production, which improved the reaction conditions for DDext. Under modified conditions (20% G6/G7, agitation speed of 100 rpm at 45 °C), DDext produced IMS (average DP = 14.5) with 65% α-(1 → 6)-glucosyl content in a good yield of 87%. KEY POINTS: • Beneficial IMS was produced using thermostabilized DDase. • Optimum conditions for reduced dextran formation were successfully determined. • A practical approach was established to provide IMS with a great yield of 87%.
• Enzymological characteristics of pepsinogens and pepsins purified from lizardfish (Saurida micropectoralis) stomach

  Sakonwat Kuepethkaew, Yi Zhang, Hideki Kishimura, Yuya Kumagai, Benjamin K. Simpson, Soottawat Benjakul, Srinivasan Damodaran, Sappasith Klomklao

  Food Chemistry 366 130532 - 130532 0308-8146 2022/01 [Refereed][Not invited]
  
• Preparation of β(1→3)/β(1→4) xylooligosaccharides from red alga dulse by two xylanases from Streptomyces thermogriseus

  Yuki Fujii, Manami Kobayashi, Yoshikatsu Miyabe, Hideki Kishimura, Tadashi Hatanaka, Yuya Kumagai

  Bioresources and Bioprocessing 8 (1) 38  2021/12 [Refereed][Not invited]
   

  Red alga dulse contains xylan with β(1→3)/β(1→4) linkages. We previously prepared xylooligosaccharides (XOSs) from dulse xylan; however, the product contained many d-xylose residues and fewer XOSs with β(1→3) linkages. To improve the efficiency of XOS production, we prepared two recombinant endoxylanases from Streptomyces thermogriseus (StXyl10 and StXyl11). Comparing the k_cat/K_m values for dulse xylan, this value from StXyl10 was approximately two times higher than that from StXyl11. We then determined the suitable conditions for XOS production. As a result, dulse XOS was prepared by the successive hydrolysis of 10 mg/mL dulse xylan by 0.5 μg/mL StXyl10 for 4 h at 50 °C and then 2.0 μg/mL StXyl11 for 36 h at 60 °C. Xylan was converted into 95.8% XOS, including 59.7% XOS with a β(1→3) linkage and 0.97% d-xylose. Our study provides useful information for the production of XOSs with β(1→3) linkages.
• Monthly Variation and Ultraviolet Stability of Mycosporine-like Amino Acids from Red Alga Dulse Palmaria palmata in Japan

  Yuki Nishida, Yoshikatsu Miyabe, Hideki Kishimura, Yuya Kumagai

  Phycology 1 (2) 119 - 128 2021/11/25 [Refereed][Not invited]
   

  Mycosporine-like amino acids (MAAs) are the natural ultraviolet (UV)-absorbing compounds from micro- and macro-algae. The MAAs in algae change with the environmental conditions and seasons. We previously determined an efficient extraction method of MAAs from red alga dulse in Usujiri (Hokkaido, Japan) and revealed monthly variation of MAA in 2019. Dulse samples in 2019 for MAA preparation were suitable from late February to April. In this study, to confirm the suitable timings to extract MAAs from Usujiri dulse, we also investigated the monthly (from January to May) variation of MAA content in 2020. There were the most MAAs in the sample on 18 March (6.696 µmol g−1 dry weight) among the samples from January to May 2020. From two years of investigation, we deduce that samples of Usujiri dulse from late February to early April were suitable for MAA preparation. The UV stability of the two major purified MAAs in Usujiri dulse—palythine and porphyra-334—was tested. The two MAAs and 2-hydroxy-4-methoxybenzophenone were stable for up to 12 h under a 312 nm lamp at 200 µW cm−2, but 2-ethylhexyl-4-methoxycinnamate formed a cis/trans-mixture in a short time. The data in this study show the suitable sampling period for Usujiri dulse and the possible application for UV protection from food and cosmetics.
• 水産加工食品のω3脂肪酸残存率に及ぼす製造条件の影響

  宮部好克, 落合瞳子, 熊谷祐也, 岸村栄毅

  日本調理科学会誌 一般社団法人 日本調理科学会 2021/11 [Refereed][Not invited]
  
• Study on the Mechanism of the Blood-Glucose-Lowering Effect of Collagen Peptides from Sturgeon By-Products

  Yukiho Sasaoka, Taichi Takagi, Shunta Michiba, Yohei Yamamoto, Yuya Kumagai, Hideki Kishimura

  Marine Drugs 19 (10) 584 - 584 2021/10/19 [Refereed][Not invited]
   

  In a previous study, we found that the collagen peptides prepared from the by-products of Bester sturgeon had an inhibitory effect on elevated blood glucose levels in a glucose tolerance test with ICR mice. In the present study, we examine the mechanism of the effect of sturgeon collagen peptides (SCPs) in detail. When glucose was orally administered to mice along with the SCPs, it was found that the glucose remained in the stomach for a longer time. In the above tests, the amount of glucose excreted in the feces of mice also increased. On the contrary, it was revealed that the SCPs have a dipeptidyl-peptidase-IV (DPP-IV) inhibitory ability in an in vitro test. In subsequent oral and intravenous glucose administration tests, glucagon-like peptide-1 (GLP-1) and insulin levels in the blood of mice were maintained at high levels. These results suggested the following three mechanisms: SCPs slow the rate of transportation of glucose from the stomach into the small intestine, resulting in delayed glucose absorption; SCPs suppress the absorption of glucose in the small intestine and excrete it from the body; SCPs inhibit DPP-IV in the blood and maintain a high GLP-1 level in blood, which in turn stimulates insulin secretion.
• ACE inhibitory effect of the protein hydrolysates prepared from commercially available nori product by pepsin–trypsin digestion

  Rie Morikawa, Keigo Toji, Yuya Kumagai, Hideki Kishimura

  European Food Research and Technology 1438-2377 2021/10/06 [Refereed][Not invited]
  
• Characterization of ACE Inhibitory Peptides Prepared from Pyropia pseudolinearis Protein

  Yuya Kumagai, Keigo Toji, Satoshi Katsukura, Rie Morikawa, Toshiki Uji, Hajime Yasui, Takeshi Shimizu, Hideki Kishimura

  Marine Drugs 19 (4) 200 - 200 2021/04/01 [Refereed][Not invited]
   

  More than 7000 red algae species have been classified. Although most of them are underused, they are a protein-rich marine resource. The hydrolysates of red algal proteins are good candidates for the inhibition of the angiotensin-I-converting enzyme (ACE). The ACE is one of the key factors for cardiovascular disease, and the inhibition of ACE activity is related to the prevention of high blood pressure. To better understand the relationship between the hydrolysates of red algal proteins and the inhibition of ACE activity, we attempted to identify novel ACE inhibitory peptides from Pyropia pseudolinearis. We prepared water soluble proteins (WSP) containing phycoerythrin, phycocyanin, allophycocyanin, and ribulose 1,5-bisphosphate carboxylase/oxygenase. In vitro analysis showed that the thermolysin hydrolysate of the WSP had high ACE inhibitory activity compared to that of WSP. We then identified 42 peptides in the hydrolysate by high-performance liquid chromatography and mass spectrometry. Among 42 peptides, 23 peptides were found in chloroplast proteins. We then synthesized the uncharacterized peptides ARY, YLR, and LRM and measured the ACE inhibitory activity. LRM showed a low IC50 value (0.15 μmol) compared to ARY and YLR (1.3 and 5.8 μmol). In silico analysis revealed that the LRM sequence was conserved in cpcA from Bangiales and Florideophyceae, indicating that the novel ACE inhibitory peptide LRM was highly conserved in red algae.
• Efficient Extraction and Antioxidant Capacity of Mycosporine-Like Amino Acids from Red Alga Dulse Palmaria palmata in Japan

  Yuki Nishida, Yuya Kumagai, Shunta Michiba, Hajime Yasui, Hideki Kishimura

  Marine Drugs 18 (10) 502 - 502 2020/09/30 [Refereed][Not invited]
   

  Mycosporine-like amino acids (MAAs) are the ultraviolet (UV)-absorbable compounds, which are naturally produced by cyanobacteria and algae. Not only these algae but also marine organisms utilize MAAs to protect their DNA from UV-induced damage. On the other hand, the content of MAAs in algae was changed by the environmental condition and season. In addition to the UV-protected function, the antioxidant capacity of MAAs can apply to the cosmetic sunscreen materials and anti-cancer for human health. In this study, we developed the efficient extraction method of MAAs from red alga dulse in Usujiri (Hokkaido, Japan) and investigated the monthly variation. We also evaluated the antioxidant capacity. We employed the successive extraction method of water and then methanol extraction. Spectrophotometric and HPLC analyses revealed that the yield of MAAs by 6 h water extraction was the highest among the tested conditions, and the content of MAAs in the sample of February was the most (6.930 µmol g−1 dry weight) among the sample from January to May in 2019. Antioxidant capacity of MAAs such as crude MAAs, the purified palythine and porphyra-334 were determined by 2,2’-azinobis(3-ethylbenzothiazoline 6-sulfonic acid) (ABTS) radical scavenging and ferrous reducing power assays in various pH conditions, showing that the highest scavenging activity and reducing power were found at alkaline condition (pH 8.0).
• The Potential of Freshwater Fish Viscus from Silver Carp Hypophthalmichthys molitrix for Trypsin Source

  Kenichiro Abe, Chunhong Yuan, Yuya Kumagai, Hideki Kishimura

  Waste and Biomass Valorization 11 (8) 3971 - 3978 1877-2641 2020/08/01 [Refereed][Not invited]
   

  © 2019, Springer Nature B.V. Abstract: Purpose Silver carp is widely cultured in China (the product reached 3.5 million ton per year), and approximately 20% of the non-edible viscera are discarded. Utilization of the viscera leads to a reduction in waste. Our previous study showed that silver carp produced two types of myosin isoforms, thermostable myosin in summer and unstable one in winter, for the adaptation of the environmental changes. Therefore, in this study, we purified trypsins from silver carp in summer and winter samples to investigate their thermostabilities. Methods: Trypsins from summer and winter samples were purified by a series of chromatographies. The temperature dependence of trypsins was determined at pH 8.0 in the range of 20–80 °C, and the effect of temperature on the thermostability was determined by measuring the remaining activity after the incubation at pH 8.0 for 15 min in the range of 20–75 °C. Results: From the summer sample, two trypsins (SSC-T1 and SSC-T2) were purified 63- and 72-fold with the yields of 24 and 21%, respectively, and a trypsin (WSC-T) was purified 81-fold with a yield of 40% from the winter sample. SSC-T1, SSC-T2 and WSC-T showed the same enzymatic characteristics, especially their optimum temperature (65 °C) and thermostability (stable below 63 °C in 15-min incubation) were similar to mammalian trypsins. Additionally, all were stable at 30 °C for 8 h in the presence of calcium-ion. Conclusion: These data indicated the silver carp viscus has a potential for thermostable trypsin source all the year round. Graphic Abstract: Thermostable characteristics of trypsins from viscera of freshwater fish including silver carp (Hypophthalmichthys molitrix).[Figure not available: see fulltext.].
• Debittering of salmon (Salmo salar) frame protein hydrolysate using 2-butanol in combination with β-cyclodextrin: Impact on some physicochemical characteristics and antioxidant activities

  Avtar Singh, Anthony Temitope Idowu, Soottawat Benjakul, Hideki Kishimura, Rotimi E. Aluko, Yuya Kumagai

  Food Chemistry 321 126686 - 126686 0308-8146 2020/08 [Refereed][Not invited]
  
• Identification of ACE inhibitory peptides from red alga Mazzaella japonica

  Yuya Kumagai, Yumi Kitade, Manami Kobayashi, Kei Watanabe, Hiroki Kurita, Hirohumi Takeda, Hajime Yasui, Hideki Kishimura

  European Food Research and Technology 1438-2377 2020/07/21 [Refereed][Not invited]
  
• 紅藻ダルス由来キシロオリゴ糖のプレバイオティクスとしての可能性

  岸村 栄毅, 熊谷 祐也

  メディカル・サイエンス・ダイジェスト 46 (7) 46 - 47 2020/07 [Not refereed][Invited]
  
• In planta particle bombardment (iPB): A new method for plant transformation and genome editing.

  Ryozo Imai, Haruyasu Hamada, Yuelin Liu, Qianyan Linghu, Yuya Kumagai, Yozo Nagira, Ryuji Miki, Naoaki Taoka

  Plant Biotechnology (Tokyo, Japan) 37 (2) 171 - 176 2020/06/25 [Refereed]
   

  Transformation is a key step in modern breeding technology that involves genome editing. The requirement for in vitro tissue culture and regeneration hampers application of this technology to commercially important varieties of many crop species. To overcome this problem, we developed a simple and reproducible in planta transformation method in wheat (Tritticum aestivum L.). Our in planta particle bombardment (iPB) method utilizes the shoot apical meristem (SAM) as a target tissue. The SAM contains a subepidermal cell layer termed L2, from which germ cells later develop during floral organogenesis. The iPB method can also be used for genome editing through transient CRISPR/Cas9 expression or direct delivery of the CRISPR/Cas9 ribonucleoprotein. In this review, we describe the iPB technology and provide an overview of its current and future applications in plant transformation and genome editing.
• In Silico Analysis of ACE Inhibitory Peptides from Chloroplast Proteins of Red Alga Grateloupia asiatica

  Kana Sumikawa, Kentaro Takei, Yuya Kumagai, Takeshi Shimizu, Hajime Yasui, Hideki Kishimura

  Marine Biotechnology 22 (3) 391 - 402 1436-2228 2020/06 [Refereed][Not invited]
  
• Identification of a Key Enzyme for the Hydrolysis of β-(1→3)-Xylosyl Linkage in Red Alga Dulse Xylooligosaccharide from Bifidobacterium Adolescentis

  Manami Kobayashi, Yuya Kumagai, Yohei Yamamoto, Hajime Yasui, Hideki Kishimura

  Marine Drugs 18 (3) 174 - 174 2020/03/20 [Refereed][Not invited]
   

  Red alga dulse possesses a unique xylan, which is composed of a linear β-(1→3)/β-(1→4)-xylosyl linkage. We previously prepared characteristic xylooligosaccharide (DX3, (β-(1→3)-xylosyl-xylobiose)) from dulse. In this study, we evaluated the prebiotic effect of DX3 on enteric bacterium. Although DX3 was utilized by Bacteroides sp. and Bifidobacterium adolescentis, Bacteroides Ksp. grew slowly as compared with β-(1→4)-xylotriose (X3) but B. adolescentis grew similar to X3. Therefore, we aimed to find the key DX3 hydrolysis enzymes in B. adolescentis. From bioinformatics analysis, two enzymes from the glycoside hydrolase family 43 (BAD0423: subfamily 12 and BAD0428: subfamily 11) were selected and expressed in Escherichia coli. BAD0423 hydrolyzed β-(1→3)-xylosyl linkage in DX3 with the specific activity of 2988 mU/mg producing xylose (X1) and xylobiose (X2), and showed low activity on X2 and X3. BAD0428 showed high activity on X2 and X3 producing X1, and the activity of BAD0428 on DX3 was 1298 mU/mg producing X1. Cooperative hydrolysis of DX3 was found in the combination of BAD0423 and BAD0428 producing X1 as the main product. From enzymatic character, hydrolysis of X3 was completed by one enzyme BAD0428, whereas hydrolysis of DX3 needed more than two enzymes.
• Complete sequence of mitochondrial DNA of Gloiopeltis furcata (Postels and Ruprecht) J. Agardh

  Watanabe Kei, Kishimoto Takahiro, Kumagai Yuya, Shimizu Takeshi, Uji Toshiki, Yasui Hajime, Kishimura Hideki

  MITOCHONDRIAL DNA PART B-RESOURCES 4 (2) 2543 - 2544 2380-2359 2019/07/03 [Refereed][Not invited]
  
• Complete sequence of mitochondrial DNA of red alga dulse Palmaria palmata (Linnaeus) Weber & Mohr in Japan

  Kumagai Yuya, Tsubouchi Ryota, Miyabe Yoshikatsu, Takeda Tomoyuki, Adachi Kohsuke, Yasui Hajime, Kishimura Hideki

  MITOCHONDRIAL DNA PART B-RESOURCES 4 (2) 3177 - 3178 2019/07/03 [Refereed][Not invited]
  
• Enzymatic production of xylooligosaccharides from red alga dulse (Palmaria sp.) wasted in Japan

  Yamamoto Yohei, Kishimura Hideki, Kinoshita Yasunori, Saburi Wataru, Kumagai Yuya, Yasui Hajime, Ojima Takao

  PROCESS BIOCHEMISTRY 82 117 - 122 1359-5113 2019/07 [Refereed][Not invited]
  
• A thermostable trypsin from freshwater fish Japanese dace (Tribolodon hakonensis): a comparison of the primary structures among fish trypsins.

  Kanno G, Klomklao S, Kumagai Y, Kishimura H

  Fish physiology and biochemistry 45 (2) 561 - 571 0920-1742 2019/04 [Refereed][Not invited]
  
• In Silico Analysis of Relationship between Proteins from Plastid Genome of Red Alga Palmaria sp. (Japan) and Angiotensin I Converting Enzyme Inhibitory Peptides.

  Kumagai Y, Miyabe Y, Takeda T, Adachi K, Yasui H, Kishimura H

  Marine drugs 17 (3) 190 - 190 2019/03 [Refereed][Not invited]
   

  Plastid proteins are one of the main components in red algae. In order to clarify the angiotensin I converting enzyme (ACE) inhibitory peptides from red alga Palmaria sp. (Japan), we determined the plastid genome sequence. The genome possesses 205 protein coding genes, which were classified as genetic systems, ribosomal proteins, photosystems, adenosine triphosphate (ATP) synthesis, metabolism, transport, or unknown. After comparing ACE inhibitory peptides between protein sequences and a database, photosystems (177 ACE inhibitory peptides) were found to be the major source of ACE inhibitory peptides (total of 751). Photosystems consist of phycobilisomes, photosystem I, photosystem II, cytochrome complex, and a redox system. Among them, photosystem I (53) and II (51) were the major source of ACE inhibitory peptides. We found that the amino acid sequence of apcE (14) in phycobilisomes, psaA (18) and psaB (13) in photosystem I, and psbB (11) and psbC (10) in photosystem II covered a majority of bioactive peptide sequences. These results are useful for evaluating the bioactive peptides from red algae.
• Antioxidant activity of proteins extracted from red alga dulse harvested in Japan

  Sato Naoto, Furuta Tomoe, Takeda Tomoyuki, Miyabe Yoshikatsu, Ura Kazuhiro, Takagi Yasuaki, Yasui Hajime, Kumagai Yuya, Kishimura Hideki

  JOURNAL OF FOOD BIOCHEMISTRY 43 (2) e12709 - e12709 0145-8884 2019/02 [Refereed][Not invited]
  
• Engineered dextranase from Streptococcus mutans enhances the production of longer isomaltooligosaccharides.

  Klahan P, Okuyama M, Jinnai K, Ma M, Kikuchi A, Kumagai Y, Tagami T, Kimura A

  Bioscience, biotechnology, and biochemistry 82 (9) 1 - 8 0916-8451 2018/05 [Refereed][Not invited]
   

  Herein, we investigated enzymatic properties and reaction specificities of Streptococcus mutans dextranase, which hydrolyzes α-(1→6)-glucosidic linkages in dextran to produce isomaltooligosaccharides. Reaction specificities of wild-type dextranase and its mutant derivatives were examined using dextran and a series of enzymatically prepared p-nitrophenyl α-isomaltooligosaccharides. In experiments with 4-mg·mL-1 dextran, isomaltooligosaccharides with degrees of polymerization (DP) of 3 and 4 were present at the beginning of the reaction, and glucose and isomaltose were produced by the end of the reaction. Increased concentrations of the substrate dextran (40 mg·mL-1) yielded isomaltooligosaccharides with higher DP, and the mutations T558H, W279A/T563N, and W279F/T563N at the -3 and -4 subsites affected hydrolytic activities of the enzyme, likely reflecting decreases in substrate affinity at the -4 subsite. In particular, T558H increased the proportion of isomaltooligosaccharide with DP of 5 in hydrolysates following reactions with 4-mg·mL-1 dextran.Abbreviations CI: cycloisomaltooligosaccharide; CITase: CI glucanotransferase; CITase-Bc: CITase from Bacillus circulans T-3040; DP: degree of polymerization of glucose unit; GH: glycoside hydrolase family; GTF: glucansucrase; HPAEC-PAD: high performance anion-exchange chromatography-pulsed amperometric detection; IG: isomaltooligosaccharide; IGn: IG with DP of n (n, 2‒5); PNP: p-nitrophenol; PNP-Glc: p-nitrophenyl α-glucoside; PNP-IG: p-nitrophenyl isomaltooligosaccharide; PNP-IGn: PNP-IG with DP of n (n, 2‒6); SmDex: dextranase from Streptococcus mutans; SmDexTM: S. mutans ATCC25175 SmDex bearing Gln100‒Ile732.
• Polysaccharide-Degrading Enzymes From Marine Gastropods

  Takao Ojima, Mohammad M. Rahman, Yuya Kumagai, Ryuji Nishiyama, Joemark Narsico, Akira Inoue

  Methods in Enzymology 605 457 - 497 1557-7988 2018/01/01 [Refereed][Not invited]
   

  Seaweed polysaccharides have been widely used as viscosifier, gelling agents, and stabilizer in the various application fields, e.g., food, pharmaceutical, nutraceutical, and chemical industries. Applications of seaweed polysaccharides are further expanding to versatile directions, e.g., biofuels, bioactive compounds, and functional materials for medical and basic researches. Production of functional oligo- and monosaccharides by the use of specific enzymes is also expected to improve the value of seaweed polysaccharides. The enzymes that depolymerize seaweed polysaccharides are distributed largely among seaweed-associating organisms like marine invertebrates and bacteria. Among them, herbivorous marine gastropods such as abalone and sea hare are the most prominent producers of polysaccharide-degrading enzymes. To date, various kinds of polysaccharide-degrading enzymes have been isolated from the digestive fluid and hepatopancreas of these animals. Among them, alginate lyase, β-1,3-glucanase, mannanase, and cellulase are the major constituents of their digestive fluid. In this chapter, the authors describe the general methods for the preparation and activity assay of the gastropod polysaccharide-degrading enzymes and provide basic knowledge for their primary structures.
• A novel glycoside hydrolase family 97 enzyme: Bifunctional beta-L-arabinopyranosidase/alpha-galactosidase from Bacteroides thetaiotaomicron

  Asako Kikuchi, Masayuki Okuyama, Koji Kato, Shohei Osaki, Min Ma, Yuya Kumagai, Kana Matsunaga, Patcharapa Kiahan, Takayoshi Tagami, Min Yao, Atsuo Kimura

  BIOCHIMIE 142 41 - 50 0300-9084 2017/11 [Refereed][Not invited]
   

  Glycoside hydrolase family 97 (GH97) is one of the most interesting glycosidase families, which contains inverting and retaining glycosidases. Currently, only two enzyme types, alpha-glucoside hydrolase and agalactosidase, are registered in the carbohydrate active enzyme database as GH97 function-known proteins. To explore new specificities, BT3661 and BT3664, which have distinct amino acid sequences when compared with that of GH97 a-glucoside hydrolase and alpha-galactosidase, were characterized in this study. BT3664 was identified to be an a-galactosidase, whereas BT3661 exhibits hydrolytic activity toward both beta-L-arabinopyranoside and alpha-D-galactopyranoside, and thus we designate BT3661 as a beta-L-arabinopyranosidase/alpha-D-galactosidase, Since this is the first dual substrate specificity enzyme in GH97, we investigated the substrate recognition mechanism of BT3661 by determining its three-dimensional structure and based on this structural data generated a number of mutants to probe the enzymatic mechanism. Structural comparison shows that the active-site pocket of BT3661 is similar to GH97 agalactosidase BT1871, but the environment around the hydroxymethyl group of the galactopyranoside is different. While BT1871 bears G1u361 to stabilize the hydroxy group of C6 through a hydrogen bond with its carboxy group, BT3661 has Asn338 at the equivalent position. Amino acid mutation analysis indicates that the length of the side chain at Asn338 is important for defining specificity of BT3661. The k(cat)/K-m value for the hydrolysis of p-nitrophenyl a-galactoside decreases when Asn338 is substituted with Glu, whereas an increase is observed when the mutation is Ala. Interestingly, mutation of Asn338 to Ala reduces the kcat/Km value for hydrolysis of p-nitrophenyl beta-D-arabinopyranoside. (C) 2017 Published by Elsevier B.V.
• Effects of mutation of Asn694 in Aspergillus niger alpha-glucosidase on hydrolysis and transglucosylation

  Min Ma, Masayuki Okuyama, Megumi Sato, Takayoshi Tagami, Patcharapa Klahan, Yuya Kumagai, Haruhide Mori, Atsuo Kimura

  APPLIED MICROBIOLOGY AND BIOTECHNOLOGY 101 (16) 6399 - 6408 0175-7598 2017/08 [Refereed][Not invited]
   

  Aspergillus niger alpha-glucosidase (ANG), a member of glycoside hydrolase family 31, catalyzes hydrolysis of alpha-glucosidic linkages at the non-reducing end. In the presence of high concentrations of maltose, the enzyme also catalyzes the formation of alpha-(1 -> 6)-glucosyl products by transglucosylation and it is used for production of the industrially useful panose and isomaltooligosaccharides. The initial transglucosylation by wild-type ANG in the presence of 100 mM maltose [Glc(alpha 1-4)Glc] yields both alpha-(1 -> 6)- and alpha-(1 -> 4)-glucosidic linkages, the latter constituting similar to 25% of the total transfer reaction product. The maltotriose [Glc(alpha 1-4)Glc(alpha 1-4)Glc], alpha-(1 -> 4)-glucosyl product disappears quickly, whereas the alpha-(1 -> 6)-glucosyl products panose [Glc(alpha 1-6)Glc(alpha 1-4)Glc], isomaltose [Glc(alpha 1-6)Glc], and isomaltotriose [Glc(alpha 1-6)Glc(alpha 1-6)Glc] accumulate. To modify the transglucosylation properties of ANG, residue Asn694, which was predicted to be involved in formation of the plus subsites of ANG, was replaced with Ala, Leu, Phe, and Trp. Except for N694A, the mutations enhanced the initial velocity of the alpha-(1 -> 4)-transfer reaction to produce maltotriose, which was then degraded at a rate similar to that by wild-type ANG. With increasing reaction time, N694F and N694W mutations led to the accumulation of larger amounts of isomaltose and isomaltotriose than achieved with the wild-type enzyme. In the final stage of the reaction, the major product was panose (N694A and N694L) or isomaltose (N694F and N694W).
• Substrate recognition of the catalytic alpha-subunit of glucosidase II from Schizosaccharomyces pombe

  Masayuki Okuyama, Masashi Miyamoto, Ichiro Matsuo, Shogo Iwamoto, Ryo Serizawa, Masanari Tanuma, Min Ma, Patcharapa Klahan, Yuya Kumagai, Takayoshi Tagami, Atsuo Kimura

  BIOSCIENCE BIOTECHNOLOGY AND BIOCHEMISTRY 81 (8) 1503 - 1511 0916-8451 2017 [Refereed][Not invited]
   

  The recombinant catalytic alpha-subunit of N-glycan processing glucosidase II from Schizosaccharomyces pombe (SpGII alpha) was produced in Escherichia coli. The recombinant SpGII alpha exhibited quite low stability, with a reduction in activity to <40% after 2-days preservation at 4 degrees C, but the presence of 10% (v/v) glycerol prevented this loss of activity. SpGII alpha, a member of the glycoside hydrolase family 31 (GH31), displayed the typical substrate specificity of GH31 alpha-glucosidases. The enzyme hydrolyzed not only alpha-(1 -> 3)-but also alpha-(1 -> 2)-, alpha-(1 -> 4)-, and alpha-(1 -> 6)-glucosidic linkages, and p-nitrophenyl alpha-glucoside. SpGII alpha displayed most catalytic properties of glucosidase II. Hydrolytic activity of the terminal alpha-glucosidic residue of Glc(2)Man(3)-Dansyl was faster than that of Glc(1)Man(3)-Dansyl. This catalytic alpha-subunit also removed terminal glucose residues from native N-glycans (Glc(2)Man(9)GlcNAc(2) and Glc(1)Man(9)GlcNAc(2)) although the activity was low.
• Molecular insights into the mechanism of thermal stability of actinomycete mannanase

  Yuya Kumagai, Misugi Uraji, Kun Wan, Masayuki Okuyama, Atsuo Kimura, Tadashi Hatanaka

  FEBS LETTERS 590 (17) 2862 - 2869 0014-5793 2016/09 [Refereed][Not invited]
   

  Streptomyces thermolilacinus mannanase (StMan), which requires Ca2+ for its enhanced thermal stability and hydrolysis activity, possesses two Ca2+-binding sites in loop6 and loop7. We evaluated the function of the Ca2+-binding site in loop7 and the hydrogen bond between residues Ser247 in loop6 and Asp279 in loop7. The Ca2+-binding in loop7 was involved only in thermal stability. Mutations of Ser247 or Asp279 retained the Ca2+-binding ability; however, mutants showed less thermal stability than StMan. Phylogenetic analysis indicated that most glycoside hydrolase family 5 subfamily 8 mannanases could be stabilized by Ca2+; however, the mechanism of StMan thermal stability was found to be quite specific in some actinomycete mannanases.
• Heat treatment of curdlan enhances the enzymatic production of biologically active beta-(1,3)-glucan oligosaccharides

  Yuya Kumagai, Masayuki Okuyama, Atsuo Kimura

  CARBOHYDRATE POLYMERS 146 396 - 401 0144-8617 2016/08 [Refereed][Not invited]
   

  Biologically active beta-(1,3)-glucan oligosaccharides were prepared from curdlan using GH64 enzyme (KfGH64). KfGH64 showed low activity toward native curdlan; thereby pretreatment conditions of curdlan were evaluated. KfGH64 showed the highest activity toward curdlan with heat treatment. The most efficient pretreatment (90 degrees C for 0.5 h) converted approximately 60% of curdlan into soluble saccharides under the optimized enzyme reaction conditions (pH 5.5, 37 degrees C, 100 rpm mixing speed, 24 h, and 10 mu g of KfGH64/1 g of curdlan). The resulting products were predominantly laminaripentaose and a small amount of p-(1,3)-glucans with an average degree of polymerization (DP) of 13 and 130. The products did not contain small oligosaccharides (DP< 5), indicating that the hydrolysis of heat-treated curdlan by KfGH64 is a suitable method for the production of biologically active beta-(1,3)-glucan oligosaccharides. (C) 2016 Elsevier Ltd. All rights reserved.
• Megalo-type alpha-1,6-glucosaccharides induce production of tumor necrosis factor alpha in primary macrophages via toll-like receptor 4 signaling

  Ga-Hyun Joe, Midori Andoh, Aki Shinoki, Weeranuch Lang, Yuya Kumagai, Juri Sadahiro, Masayuki Okuyama, Atsuo Kimura, Hidehisa Shimizu, Hiroshi Hara, Satoshi Ishizuka

  BIOMEDICAL RESEARCH-TOKYO 37 (3) 179 - 186 0388-6107 2016 [Refereed][Not invited]
   

  The term "megalo-saccharide" is used for saccharides with ten or more saccharide units, whereas the term "oligo-saccharide" is used for saccharides containing fewer than ten monosaccharide units. Megalo-type alpha-1,6-glucosaccharide (M-IM) is a non-digestible saccharide and not utilized by intestinal bacteria, suggesting that ingested M-IM may encounter ileum Peyer's patches that contains immune cells such as macrophages. Macrophages are responsible for antigen incorporation and presentation during the initial step of immune responses. We investigated whether M-IMs modulate macrophage functions such as cytokine production, nitric oxide production, cell viability, and phagocytosis. Primary macrophages collected from the rats were cultured with the existence of M-IM or lipopolysaccharides (LPS). M-IM and LPS induced the production of tumor necrosis factor alpha (TNF alpha), interleukin 6 (IL6), and nitric oxide in the primary macrophages. The gene expression profile of inflammatory factors including TNF alpha, IL6, and IL1 beta in M-IM-stimulated cells was similar to that of LPS-stimulated cells. The M-IM did not affect phagocytosis in the primary macrophages. The M-IM-induced TNF alpha production was suppressed in the cells treated with a toll-like receptor 4 (TLR4) inhibitor called TAK-242. In conclusion, the M-IM modulates cytokine expression via TLR4 signaling and may play a role in the modulation of immune responses.
• The loop structure of Actinomycete glycoside hydrolase family 5 mannanases governs substrate recognition

  Yuya Kumagai, Keitaro Yamashita, Takayoshi Tagami, Misugi Uraji, Kun Wan, Masayuki Okuyama, Min Yao, Atsuo Kimura, Tadashi Hatanaka

  FEBS JOURNAL 282 (20) 4001 - 4014 1742-464X 2015/10 [Refereed][Not invited]
   

  Endo--1,4-mannanases from Streptomyces thermolilacinus (StMan) and Thermobifida fusca (TfMan) demonstrated different substrate specificities. StMan hydrolyzed galactosylmannooligosaccharide (GGM5; 6(III),6(IV)--d-galactosyl mannopentaose) to GGM3 and M2, whereas TfMan hydrolyzed GGM5 to GGM4 and M1. To determine the region involved in the substrate specificity, we constructed chimeric enzymes of StMan and TfMan and evaluated their substrate specificities. Moreover, the crystal structure of the catalytic domain of StMan (StMandC) and the complex structure of the inactive mutant StE273AdC with M6 were solved at resolutions of 1.60 and 1.50 angstrom, respectively. Structural comparisons of StMandC and the catalytic domain of TfMan lead to the identification of a subsite around -1 in StMandC that could accommodate a galactose branch. These findings demonstrate that the two loops (loop7 and loop8) are responsible for substrate recognition in GH5 actinomycete mannanases. In particular, Trp281 in loop7 of StMan, which is located in a narrow and deep cleft, plays an important role in its affinity toward linear substrates. Asp310 in loop8 of StMan specifically bound to the galactosyl unit in the -1 subsite.
• Biochemical properties and substrate recognition mechanism of GH31 alpha-glucosidase from Bacillus sp AHU 2001 with broad substrate specificity

  Wataru Saburi, Masayuki Okuyama, Yuya Kumagai, Atsuo Kimura, Haruhide Mori

  BIOCHIMIE 108 140 - 148 0300-9084 2015/01 [Refereed][Not invited]
   

  alpha-Glucosidases are ubiquitous enzymes that hydrolyze the alpha-glucosidic linkage at the non-reducing end of substrates. In this study, we characterized an alpha-glucosidase (BspAG31A) belonging to glycoside hydrolase family 31 from Bacillus sp. AHU 2001. Recombinant B5pAG31A, produced in Escherichia colt, had high hydrolytic activity toward maltooligosaccharides, kojibiose, nigerose, and neotrehalose. This is the first report of an alpha-glucosidase with high activity toward neotrehalose. The transglucosylation products, nigerose, kojibiose, isomaltose, and neotrehalose, were generated from 440 mm maltose. Substitution of Tyr268, situated on the beta -> alpha loop 1 of B5pAG31A, with Trp increased hydrolytic activity toward isomaltose. This mutation reduced the hydrolytic activity toward maltooligosaccharides more than toward kojibiose, nigerose, and neotrehalose. Analysis of the Y173A mutant of B5pAG31A showed that Tyr173, situated on the N-terminal domain loop, is associated with the formation of subsite +2. In Y173A, the k(cad)/K-m for maltooligosaccharides slightly decreased with an increasing degree of polymerization compared with wild type. Among the amino acid residues surrounding the substrate binding site, Va1543 and Glu545 of B5pAG31A were different from the corresponding residues of Bacillus thermoamyloliquefaciens alpha-glucosidase II, which has higher activity toward isomaltose than B5pAG31A. The E545G mutation slightly enhanced isomaltase activity without a large reduction of hydrolytic activities toward other substrates. V543A showed 1.8-3.5-fold higher hydrolytic activities toward all substrates other than neotrehalose compared with wild type, although its preference for isomaltose was unchanged. (C) 2014 Elsevier B.V. and Societe francaise de biochimie et biologie Moleculaire (SFBBM). All rights reserved.
• Different molecular complexity of linear-isomaltomegalosaccharides and beta-cyclodextrin on enhancing solubility of azo dye ethyl red: Towards dye biodegradation

  Weeranuch Lang, Yuya Kumagai, Juri Sadahiro, Janjira Maneesan, Masayuki Okuyama, Haruhide Mori, Nobuo Sakairi, Atsuo Kimura

  BIORESOURCE TECHNOLOGY 169 518 - 524 0960-8524 2014/10 [Refereed][Not invited]
   

  Intermolecular interaction of linear-type alpha-(1 -> 6)-glucosyl megalosaccharide rich (L-IMS) and water-insoluble anionic ethyl red was firstly characterized in a comparison with inclusion complexation by cyclodextrins (CDs) to overcome the problem of poor solubility and bioavailability. Phase solubility studies indicated an enhancement of 3- and 9-fold over the solubility in water upon the presence of L-IMS and beta-CD, respectively. H-1 NMR and circular dichrosim spectra revealed the dye forms consisted of 1:1 stoichiometric inclusion complex within the beta-CD cavity, whereas they exhibited non-specific hydrophobic interaction, identified by solvent polarity changes, with L-IMS. The inclusion complex delivered by beta-CD showed an uncompetitive inhibitory-type effect to azoreductase, particularly with high water content that did not promote dye liberation. Addition of the solid dye dispersed into coupled-enzyme reaction system supplied by L-IMS as the dye solubilizer provided usual degradation rate. The dye intermission in series exhibited successful removal with at least 5 cycles was economically feasible. (C) 2014 Elsevier Ltd. All rights reserved.
• A laminaribiose-hydrolyzing enzyme, AkLab, from the common sea hare Aplysia kurodai and its transglycosylation activity

  Yuya Kumagai, Takuya Satoh, Akira Inoue, Takao Ojima

  COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY B-BIOCHEMISTRY & MOLECULAR BIOLOGY 167 1 - 7 1096-4959 2014/01 [Refereed][Not invited]
   

  Endo-beta-1,3-glucanases (laminarinase, EC 3.2.1.6) from marine molluscs specifically degrades laminarin from brown algae producing laminaribiose and glucose, but hardly degrades laminaribiose. For the complete depolymerization of laminarin, other enzymes that can hydrolyze laminaribiose appear to be necessary. In the present study, we successfully isolated a laminaribiose-hydrolyzing enzyme from the digestive fluid of a marine gastropod Aplysia kurodai by ammonium sulfate fractionation followed by conventional column chromatographies. This enzyme, AkLab, named after the scientific name of this animal and substrate specificity toward laminaribiose, shows an approximate molecular mass of 110 kDa on SDS-PAGE, and optimum pH and temperature at around pH 5.5 and 50 degrees C, respectively. AkLab rapidly hydrolyzes laminaribiose and p-nitrophenyl-beta-D-glucoside, and slowly cellobiose, gentiobiose and lactose, but not sucrose and maltose. AkLab shows high transglycosylation activity and can produce a series of laminarioligosaccharides larger than laminaritetraose from laminaribiose (a donor substrate) and laminaritriose (an acceptor substrate). This enzyme is suggested to be a member of glycosyl hydrolase family 1 by the analysis of partial amino-acid sequences. (C) 2013 Elsevier Inc. All rights reserved.
• Enzymatic production of ferulic acid from defatted rice bran by using a combination of bacterial enzymes

  Misugi Uraji, Masayo Kimura, Yosikazu Inoue, Kayoko Kawakami, Yuya Kumagai, Koichi Harazono, Tadashi Hatanaka

  Applied Biochemistry and Biotechnology 171 (5) 1085 - 1093 0273-2289 2013/11 [Refereed][Not invited]
   

  Ferulic acid (FA), which is present in the cell walls of some plants, is best known for its antioxidant property. By combining a commercial enzyme that shows FA esterase activity with several Streptomyces carbohydrate-hydrolyzing enzymes, we succeeded in enhancing the enzymatic production of FA from defatted rice bran. In particular, the combination of three xylanases, an α-l-arabinofuranosidase, and an acetyl xylan esterase from Streptomyces spp. produced the highest increase in the amount of released FAs among all the enzymes in the Streptomyces enzymes library. This enzyme combination also had an effect on FA production from other biomasses, such as raw rice bran, wheat bran, and corncob. © 2013 Springer Science+Business Media New York.
• Effect of the binding of bivalent ion to the calcium-binding site responsible for the thermal stability of actinomycete mannanase: Potential use in production of functional mannooligosaccharides

  Yuya Kumagai, Kayoko Kawakami, Misugi Uraji, Tadashi Hatanaka

  JOURNAL OF MOLECULAR CATALYSIS B-ENZYMATIC 94 63 - 68 1381-1177 2013/10 [Refereed][Not invited]
   

  In a previous study, we determined that the calcium-binding site in the catalytic domain of actinomycete mannanases is responsible for the thermal stability [18]. To evaluate whether the calcium-binding site could bind to other bivalent ions, we measured the ability of mannanase to bind bivalent ions by using isothermal titration calorimetry (ITC) by employing the catalytic domain mutants StMandC (from Streptomyces thermolilacinus) and TfMandC (from Thermobifida fusca) and the calcium-binding site deletion mutants StDEDAAAdC and TfDEDAAAdC. The calcium-binding site in StMandC and TfMandC bound bivalent ions with a K-a of 0.10 x 10(4) to 3.02 x 10(4) M-1 and 0.21 x 10(4) to 1.52 x 10(4) M-1, respectively. Among the tested bivalent ions, thermal stability was enhanced in the following order: magnesium, manganese, and calcium. Magnesium barely enhanced the thermal stability in mannanases. On the other hand, StDEDAAAdC and TfDEDAAAdC did not bind to the tested bivalent ions. From these results, we showed that the calcium-binding site is involved in the binding of the other bivalent ions. The association constant comprised of negative enthalpy and low entropy was suitable for bivalent ion binding in actinomycete mannanases. (c) 2013 Elsevier B.V. All rights reserved.
• Enzymatic properties and primary structures of two α-amylase isozymes from the Pacific abalone Haliotis discus hannai

  Yuya Kumagai, Takuya Satoh, Akira Inoue, Takao Ojima

  Comparative Biochemistry and Physiology - B Biochemistry and Molecular Biology 2 164 (2) 80 - 88 1096-4959 2013/02 [Refereed][Not invited]
   

  Two α-amylase (EC 3.2.1.1) isozymes, HdAmy58 and HdAmy82, with approximate molecular masses of 58. kDa and 82. kDa, respectively, were isolated from the digestive fluid of the Pacific abalone Haliotis discus hannai. Optimal temperatures and pHs for HdAmy58 and HdAmy82 were at 30 °C and 6.7, and 30 °C and 6.1, respectively. Both enzymes similarly degraded starch, glycogen, and maltooligosaccharides larger than maltotriose producing maltose and maltotriose as the major degradation products. However, the activity toward maltotetraose was appreciably higher in HdAmy82 than HdAmy58. cDNAs encoding HdAmy58 and HdAmy82 were cloned and the amino-acid sequences of 511 and 694 residues for HdAmy58 and HdAmy82, respectively, were deduced. The putative catalytic domains of HdAmy58 and HdAmy82 were located in the 17-511th and 19-500th amino-acid regions, respectively, and they showed approximately 50% amino-acid identity to each other. These sequences also showed 62-99% amino-acid identity to the catalytic domains of known α-amylases that belong to glycoside-hydrolase-family 13. The difference in the molecular masses between HdAmy58 and HdAmy82 was ascribed to the extension of approximately 190 residues in the C-terminus of HdAmy82. This extended region showed 41-63% amino-acid identity with the ancillary domains of several α-amylases previously reported. © 2012 Elsevier Inc.
• Binding of bivalent ions to actinomycete mannanase is accompanied by conformational change and is a key factor in its thermal stability

  Yuya Kumagai, Kayoko Kawakami, Misugi Uraji, Tadashi Hatanaka

  Biochimica et Biophysica Acta - Proteins and Proteomics 1834 (1) 301 - 307 1570-9639 2013/01 [Refereed][Not invited]
   

  The study aimed to define the key factors involved in the modulation of actinomycete mannanases. We focused on the roles of carbohydrate-binding modules (CBMs) and bivalent ions. To investigate the effects of these factors, two actinomycete mannanase genes were cloned from Streptomyces thermoluteus (StManII) and Streptomyces lividans (SlMan). CBMs fused to mannanase catalytic domains do not affect the thermal stability of the proteins. CBM2 of StManII increased the catalytic efficiency toward soluble-mannan and insoluble-mannan by 25%-36%, and CBM10 of SlMan increased the catalytic efficiency toward soluble-mannan by 40%-50%. Thermal stability of wild-type and mutant enzymes was enhanced by calcium and manganese. Thermal stability of SlMandC was also slightly enhanced by magnesium. These results indicated that bivalent ion-binding site responsible for thermal stability was in the catalytic domains. Thermal stability of mannanase differed in the kinds of bivalent ions. Isothermal titration calorimetry revealed that the catalytic domain of StManII bound bivalent ions with a Ka of 5.39 ± 0.45 × 10 3-7.56 ± 1.47 × 103 M- 1, and the catalytic domain of SlMan bound bivalent ions with a Ka of 1.06 ± 0.34 × 103-3.86 ± 0.94 × 103 M- 1. The stoichiometry of these bindings was consistent with one bivalent ion-binding site per molecule of enzyme. Circular dichroism spectrum revealed that the presence of bivalent ions induced changes in the secondary structures of the enzymes. The binding of certain bivalent ion responsible for thermal stability was accompanied by a different conformational change by each bivalent ion. Actinomycete mannanases belong to GHF5 which contained various hemicellulases therefore, the information obtained from mannanases applies to the other enzymes. © 2012 Elsevier B.V. All rights reserved.
• A novel mechanism for the promotion of quercetin glycoside absorption by megalo alpha-1,6-glucosaccharide in the rat small intestine

  Aki Shinoki, Weeranuch Lang, Charin Thawornkuno, Hee-Kwon Kang, Yuya Kumagai, Masayuki Okuyama, Haruhide Mori, Atsuo Kimura, Satoshi Ishizuka, Hiroshi Hara

  FOOD CHEMISTRY 136 (2) 293 - 296 0308-8146 2013/01 [Refereed][Not invited]
   

  The presence of an alpha-1,6-glucosaccharide enhances absorption of water-soluble quercetin glycosides, a mixture of quercetin-3-O-beta-D-glucoside (Q3G, 31.8%), mono (23.3%), di (20.3%) and more D-glucose adducts with alpha-1,4-linkage to a D-glucose moiety of Q3G, in a ligated small intestinal loop of anesthetized rats. We prepared alpha-1,6-glucosaccharides with different degrees of polymerization (DP) enzymatically and separated them into a megalo-isomaltosaccharide-containing fraction (M-IM, average DP = 11.0) and an oligo-isomaltosaccharide-containing fraction (O-IM, average DP = 3.6). Luminal injection of either saccharide fraction promoted the absorption of total quercetin-derivatives from the small intestinal segment and this effect was greater for M-IM than O-IM addition. M-IM also increased Q3G, but not the quercetin aglycone, concentration in the water-phase of the luminal contents more strongly than O-IM. The enhancement of Q3G solubilization in the luminal contents may be responsible for the increases in the quercetin glucoside absorption promoted by alpha-1,6-glucosaccharides, especially that by M-IM. These results suggest that the ingestion of alpha-1,6-glucosaccharides promotes Q3G bioavailability. (C) 2012 Elsevier Ltd. All rights reserved.
• The structural analysis and the role of calcium binding site for thermal stability in mannanase

  Yuya Kumagai, Kayoko Kawakami, Takafumi Mukaihara, Masayo Kimura, Tadashi Hatanaka

  BIOCHIMIE 94 (12) 2783 - 2790 0300-9084 2012/12 [Refereed][Not invited]
   

  Mannanase is an important enzyme involved in the degradation of mannan, production of bioactive oligosaccharides, and biobleaching of kraft pulp. Mannanase must be thermostable for use in industrial applications. In a previous study, we found that the thermal stability of mannanase from Streptomyces thermolilacinus (StMan) and Thermobifida fusca (TfMan) is enhanced by calcium. Here, we investigated the relationship between the three-dimensional structure and primary sequence to identify the putative calcium-binding site. The results of site-directed mutagenesis experiments indicated that Asp-285, Glu-286, and Asp-287 of StMan (StDEDAAAdC) and Asp-264, Glu-265, and Asp-266 of TfMan (TfDEDAAAdC) were the key residues for calcium binding affinity. Isothermal titration calorimetry revealed that the catalytic domain of StMan and TfMan (StMandC and TfMandC, respectively) bound calcium with a K-a of 3.02 x 10(4) M-1 and 1.52 x 10(4) M-1, respectively, both with stoichiometry consistent with one calcium-binding site per molecule of enzyme. Non-calcium-binding mutants (StDEDAAAdC and TfDEDAAAdC) did not show any calorimetric change. From the primary structure alignment of several mannanases, the calcium-binding site was found to be highly conserved in GH5 bacterial mannanases. This is the first study indicating enhanced thermal stability of GH5 bacterial mannanases by calcium binding. (C) 2012 Elsevier Masson SAS. All rights reserved.
• The Delay in the Development of Experimental Colitis from Isomaltosyloligosaccharides in Rats Is Dependent on the Degree of Polymerization

  Hitoshi Iwaya, Jae-Sung Lee, Shinya Yamagishi, Aki Shinoki, Weeranuch Lang, Charin Thawornkuno, Hee-Kwon Kang, Yuya Kumagai, Shiho Suzuki, Shinichi Kitamura, Hiroshi Hara, Masayuki Okuyama, Haruhide Mori, Atsuo Kimura, Satoshi Ishizuka

  PLOS ONE 7 (11) e50658  1932-6203 2012/11 [Refereed][Not invited]
   

  Background: Isomaltosyloligosaccharides (IMO) and dextran (Dex) are hardly digestible in the small intestine and thus influence the luminal environment and affect the maintenance of health. There is wide variation in the degree of polymerization (DP) in Dex and IMO (short-sized IMO, S-IMO; long-sized IMO, L-IMO), and the physiological influence of these compounds may be dependent on their DP. Methodology/Principal Findings: Five-week-old male Wistar rats were given a semi-purified diet with or without 30 g/kg diet of the S-IMO (DP = 3.3), L-IMO (DP = 8.4), or Dex (DP = 1230) for two weeks. Dextran sulfate sodium (DSS) was administered to the rats for one week to induce experimental colitis. We evaluated the clinical symptoms during the DSS treatment period by scoring the body weight loss, stool consistency, and rectal bleeding. The development of colitis induced by DSS was delayed in the rats fed S-IMO and Dex diets. The DSS treatment promoted an accumulation of neutrophils in the colonic mucosa in the rats fed the control, S-IMO, and L-IMO diets, as assessed by a measurement of myeloperoxidase (MPO) activity. In contrast, no increase in MPO activity was observed in the Dex-diet-fed rats even with DSS treatment. Immune cell populations in peripheral blood were also modified by the DP of ingested saccharides. Dietary S-IMO increased the concentration of n-butyric acid in the cecal contents and the levels of glucagon-like peptide-2 in the colonic mucosa. Conclusion/Significance: Our study provided evidence that the physiological effects of alpha-glucosaccharides on colitis depend on their DP, linkage type, and digestibility. Citation: Iwaya H, Lee J-S, Yamagishi S, Shinoki A, Lang W, et al. (2012) The Delay in the Development of Experimental Colitis from Isomaltosyloligosaccharides in Rats Is Dependent on the Degree of Polymerization. PLoS ONE 7(11): e50658. doi: 10.1371/journal.pone.0050658
• Production of dipeptidyl peptidase IV inhibitory peptides from defatted rice bran

  Tadashi Hatanaka, Yosikazu Inoue, Jiro Arima, Yuya Kumagai, Hirokazu Usuki, Kayoko Kawakami, Masayo Kimura, Takafumi Mukaihara

  FOOD CHEMISTRY 134 (2) 797 - 802 0308-8146 2012/09 [Refereed][Not invited]
   

  The insulinotropic hormone glucagon-like peptide-1 is metabolised extremely rapidly by the ubiquitous enzyme dipeptidyl peptidase IV (DPP-IV). Therefore, human DPP-IV is a key regulator involved in the prevention and treatment of type 2 diabetes. To simplify the method of producing an inhibitory peptide against DPP-IV, we focused on rice bran (RB) as a source and subjected proteins from defatted RB to enzymatic proteolysis using 2 commercial enzymes. The RB peptides produced with Umamizyme G exhibited 10 times the inhibitory activity as those produced with Bioprase SP. The half-maximal inhibitory concentration (IC50) value of the RB peptides was 2.3 +/- 0.1 mg/ml. Leu-Pro and Ile-Pro were identified as the inhibitory peptides among the RB peptides produced with Umamizyme G. Ile-Pro was the strongest DPP-IV inhibitor among the 15 Xaa-Pro dipeptides and Pro-lie tested. Ile-Pro competitively inhibited DPP-IV (K-i = 0.11 mM). Mass spectrometry indicated that the contents of Leu-Pro and Ile-Pro in the RB peptides were 2.91 +/- 0.52 mu g/mg. (C) 2012 Elsevier Ltd. All rights reserved.
• Preparation of hemicellulolic oligosaccharides from Chamaecyparis obtuse (Hinoki) slurry using commercial enzymes

  Yuya Kumagai, Hirokazu Usuki, Yukihiro Yamamoto, Akihiro Yamasato, Takafumi Mukaihara, Tadashi Hatanaka

  Frontiers of Chemical Science and Engineering 6 (2) 224 - 231 2095-0179 2012/06 [Refereed][Not invited]
   

  Wood biomass is anticipated to serve as a substitute for carbon source, which has no feedstock competition with foods. Biomass is commonly used for the production of bio-ethanol by a series of processes such as pretreatment, enzymatic degradation, and fermentation. Hemicellulose, constituting 20 wt-%-40 wt-% of biomass materials, contains various kinds of saccharides known to be bioactive substrates. Practical usage of hemicellulose is generally limited to its conversion to bio-ethanol. Here, we aimed to prepare hemicellulolic oligosaccharides, more valuable products other than ethanol. Therefore, the Hinoki slurry was treated with lime at room temperature for 3 h, and then neutralized with HCl. The resulting sample was treated with 13 types of commercial enzymes, and the saccharides produced in the supernatant were evaluated. The result showed that the commercial enzyme Cellulase SS (Nagase & Co., LTD.) effectively degraded the slurry to produce disaccharides and trisaccharides. Analysis of sugar components by liquid chromatography/mass spectrography (LC/MS) after the derivation with ethyl 4-aminobenzoate (ABEE) showed that mannobiose, mannotriose, and cellobiose were the major oligosaccharides. These results indicate valuable oligosaccharides can be successfully produced from Hinoki softwood slurry. © 2012 Higher Education Press and Springer-Verlag Berlin Heidelberg.
• Characterization of calcium ion sensitive region for beta-Mannanase from Streptomyces thermolilacinus

  Yuya Kumagai, Hirokazu Usuki, Yukihiro Yamamoto, Akihiro Yamasato, Jiro Arima, Takafumi Mukaihara, Tadashi Hatanaka

  BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 9 1814 (9) 1127 - 1133 1570-9639 2011/09 [Refereed][Not invited]
   

  Despite the widespread industrial applications of beta-mannanase, the relations between the enzymatic properties and metal ions remain poorly understood. To elucidate the effects of metal ions on beta-mannanase, thermal stability and hydrolysis activity were characterized. The stman and tfman genes encoding p-mannanase (EC.3.2.1.78) from Streptomyces thermolilacinus NBRC14274 and Thermobifida fusca NBRC14071 were cloned and expressed in Escherichia coli. The thermal stability of each enzyme shifted to the 7-9 degrees C high temperature in the presence of Ca2+ compared with that in the absence of Ca2+. These results show that the thermal stability of StMan and TfMan was enhanced by the presence of Ca2+. StMan, but not TfMan, required Ca2+ for the hydrolysis activity. To identify the Ca2+ sensitive region of StMam we prepared eight chimeric enzymes. Based on the results of the relationship between Ca2+ and hydrolysis activity, the region of amino-acid residues 244-349 of StMan was responsible for a Ca2+ sensitive site. (C) 2011 Elsevier B.V. All rights reserved.
• Synthesis of prolyl-hydroxyproline using prolyl aminopeptidase from Streptomyces aureofaciens TH-3

  Yukihiro Yamamoto, Hirokazu Usuki, Yuya Kumagai, Takafumi Mukaihara, Akihiro Yamasato, Tadashi Hatanaka

  PROCESS BIOCHEMISTRY 46 (8) 1560 - 1564 1359-5113 2011/08 [Refereed][Not invited]
   

  Despite attention devoted to prolyl-hydroxyproline (Pro-Hyp) in nutraceuticals and pharmaceuticals, its enzymatic synthesis has not been achieved. This study investigated aminolysis reaction from proline esters or amide and hydroxyproline using prolyl aminopeptidases from Streptomyces aureofaciens TH-3 (PAP TH-3). The effects of pH, buffer concentration, reaction temperature, and the type and concentration of the acyl donor were examined for the aminolysis activity of PAP TH-3. The Pro-Hyp synthesis was conducted in alkaline conditions at low temperature. The type of acyl donor also affected the yield. Finally, optimum conditions were established as 5 mu l of 1 M proline amide, 50 mu l of 2 M hydroxyl-proline, 40 mu l of 1200 mM boric buffer (pH 11), 5 mu l of water containing 10 mu g PAP TH-3, 4 degrees C and 3 h. Based on the acyl donor. 30% of the maximum yield was obtained. (C) 2011 Elsevier Ltd. All rights reserved.
• Extracellular Production and Characterization of Streptomyces X-prolyl Dipeptidyl Aminopeptidase

  Tadashi Hatanaka, Akihiro Yamasato, Jiro Arima, Hirokazu Usuki, Yukihiro Yamamoto, Yuya Kumagai

  APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY 164 (4) 475 - 486 0273-2289 2011/06 [Refereed][Not invited]
   

  X-prolyl dipeptidyl aminopeptidases (X-PDAPs) are useful in various food industries. In this study, we performed sequence-based screening to obtain a stable X-PDAP enzyme from thermophilic Streptomyces strains. We found three genes that encoded X-PDAP from Streptomyces thermoluteus subsp. fuscus NBRC 14270 (14270 X-PDAP), Streptomyces thermocyaneoviolaceus NBRC 14271 (14271 X-PDAP), and Streptomyces thermocoerulescens NBRC 14273, which were subsequently cloned and sequenced. The deduced amino acid sequences of these genes showed high similarity, with similar to 80% identity with each other. The isolated X-PDAPs and an X-PDAP from Streptomyces coelicolor were expressed in Streptomyces lividans using a hyperexpression vector: pTONA5a. Among these genes, only 14270 and 14271 X-PDAPs caused overexpression and extracellular production without artificial signal peptides. We also characterized the biochemical properties of purified 14271 X-PDAP. In addition, we found that, in peptide synthesis via an aminolysis reaction, this enzyme recognized d-amino acid derivatives as acyl acceptors, similar to l-amino acid derivatives.
• Extracellular Production and Characterization of Two Streptomyces L-Asparaginases

  Tadashi Hatanaka, Hirokazu Usuki, Jiro Arima, Yoshiko Uesugi, Yukihiro Yamamoto, Yuya Kumagai, Akihiro Yamasato, Takafumi Mukaihara

  APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY 163 (7) 836 - 844 0273-2289 2011/04 [Refereed][Not invited]
   

  L-Asparaginase (ASNase) has proved its use in medical and food industries. Sequence-based screening showed the thermophilic Streptomyces strain Streptomyces thermoluteus subsp. fuscus NBRC 14270 (14270 ASNase) to positive against predicted ASNase primary sequences. The 14270 ASNase gene and four L-asparaginase genes from Streptomyces coelicolor, Streptomyces avermitilis, and Streptomyces griseus (SGR ASNase) were expressed in Streptomyces lividans using a hyperexpression vector: pTONA5a. Among those genes, only 14270 ASNase and SGR ASNase were successful for overexpression and detected in culture supernatants without an artificial signal peptide. Comparison of the two Streptomyces enzymes described above demonstrated that 14270 ASNase was superior to SGR ASNase in terms of optimum temperature, thermal stability, and pH stability.
• MS/MS fragmentation-guided search of TMG-chitooligomycins and their structure-activity relationship in specific beta-N-acetylglucosaminidase inhibition

  Hirokazu Usuki, Yukihiro Yamamoto, Yuya Kumagai, Teruhiko Nitoda, Hiroshi Kanzaki, Tadashi Hatanaka

  ORGANIC & BIOMOLECULAR CHEMISTRY 9 (8) 2943 - 2951 1477-0520 2011 [Refereed][Not invited]
   

  The reducing tetrasaccharide TMG-chitotriomycin (1) is an inhibitor of beta-N-acetylglucosaminidase (GlcNAcase), produced by the actinomycete Streptomyces anulatus NBRC13369. The inhibitor shows a unique inhibitory spectrum, that is, selectivity toward enzymes from chitin-containing organisms such as insects and fungi. Nevertheless, its structure-selectivity relationship remains to be clarified. In this study, we conducted a structure-guided search of analogues of 1 in order to obtain diverse N,N,N-trimethylglucosaminium (TMG)-containing chitooligosaccharides. In this approach, the specific fragmentation profile of 1 on ESI-MS/MS analysis was used for the selective detection of desired compounds. As a result, two new analogues, named TMG-chitomonomycin (3) and TMG-chitobiomycin (2), were obtained from a culture filtrate of 1-producing Streptomyces. Their enzyme-inhibiting activity revealed that the potency and selectivity depended on the degree of polymerization of the reducing end GlcNAc units. Furthermore, a computational modeling study inspired the inhibitory mechanism of TMG-related compounds as a mimic of the substrate in the Michaelis complex of the GH20 enzyme. This study is an example of the successful application of a MS/MS experiment for structure-guided isolation of natural products.
• Isolation and characterization of two types of beta-1,3-glucanases from the common sea hare Aplysia kurodai

  Yuya Kumagai, Takao Ojima

  COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY B-BIOCHEMISTRY & MOLECULAR BIOLOGY 155 (2) 138 - 144 1096-4959 2010/02 [Refereed][Not invited]
   

  Two types of beta-1,3-glucanases, AkLam36 and AkLam33 with the molecular masses of 36 kDa and 33 kDa, respectively, were isolated from the digestive fluid of the common sea hare Aplysia kurodai. AkLam36 was regarded as an endolytic enzyme (EC 32.1.6) degrading laminarin and laminarioligosaccharides to laminaritriose, laminaribiose, and glucose, while AkLam33 was regarded as an exolytic enzyme (EC 32.1.58) directly producing glucose from polymer laminarin. AkLam36 showed higher activity toward beta-1,3-glucans with a few beta-1,6-linked glucose branches such as Laminaria digitata laminarin (LLam) than highly branched beta-1,3-glucans such as Eisenia bicyclis laminarin (ELam). AkLam33 showed moderate activity toward both Ram and LLam and high activity toward smaller substrates such as laminaritetraose and laminaritriose. Although both enzymes did not degrade laminaribiose as a sole substrate, they were capable of degrading it via transglycosylation reaction with laminaritriose. The N-terminal amino-acid sequences of AkLam36 and AkLam33 indicated that both enzymes belong to the glycosyl hydrolase family 16 like other molluscan beta-1,3-glucanases. (C) 2009 Elsevier Inc. All rights reserved.
• Enzymatic properties and the primary structure of a beta-1,3-glucanase from the digestive fluid of the Pacific abalone Haliotis discus hannai

  Yuya Kumagai, Takao Ojima

  COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY B-BIOCHEMISTRY & MOLECULAR BIOLOGY 154 (1) 113 - 120 1096-4959 2009/09 [Refereed][Not invited]
   

  A beta-1,3-glucanase (EC 3.2.1.6) with a molecular mass of 33 kDa was isolated from the digestive fluid of the Pacific abalone Haliotis discus hannai by ammonium sulfate fractionation followed by conventional column chromatography. This enzyme, named HdLam33 in the present study, degraded laminarin and laminarioligosaccharides to laminaribiose and glucose with the optimal temperature and pH at 50 degrees C and 6.0, respectively. HdLam33 possessed transglycosylation activity, a characteristic property of glucan hydrolases that split glycoside linkage with a retaining manner. By the transglycosylation reaction of HdLam33, the laminaribiose unit in the non-reducing terminus of laminaritriose (donor substrate) was transferred to a free laminaribiose (acceptor substrate) resulting to laminaritetraose and glucose. The resulting laminaritetraose was subsequently hydrolyzed by HdLam33 into 2 mol of glucose and 1 mol of laminaribiose. The primary structure of HdLam33 was analyzed by the cDNA method. The deduced amino-acid sequence of 329 residues corresponding to the catalytic domain of HdLam33 showed 56-61% amino-acid identity with those of other molluscan beta-1,3-glucanases which have been identified as glycoside hydrolase family 16 enzymes. (C) 2009 Elsevier Inc. All rights reserved.
• Comparative study on general properties of alginate lyases from some marine gastropod mollusks

  Mami Hata, Yuya Kumagai, Mohammad Matiur Rahman, Satoru Chiba, Hiroyuki Tanaka, Akira Inoue, Takao Ojima

  FISHERIES SCIENCE 75 (3) 755 - 763 0919-9268 2009/05 [Refereed][Not invited]
   

  Alginate lyase (EC 4.2.2.3) is an enzyme that splits glycosyl linkages of alginate chain via beta-elimination, producing unsaturated oligoalginates. This enzyme is widely distributed in herbivorous marine mollusks, brown algae, and marine and soil bacteria. In the present study, we determined the general properties and partial amino acid sequences of alginate lyases from three Archeogastropoda, i.e., Haliotis discus hannai, H. iris, and Omphalius rusticus, and one Mesogastropoda, i.e., Littorina brevicula, in order to enrich the information about functional and structural diversity in gastropod alginate lyases. The alginate lyases were extracted from hepatopancreas of these animals and purified by ammonium sulfate fractionation followed by conventional column chromatography. Single alginate lyases with molecular masses of approximately 28, 34, and 34 kDa were isolated from H. discus, H. iris, and O. rusticus, respectively. While three alginate lyases with molecular masses of 35, 32, and 28 kDa were isolated from L. brevicula. These enzymes were identified as poly(M) lyase (EC 4.2.2.3) since they preferably degraded poly(M)-rich substrate. Western blot analysis using an antiserum raised against H. discus enzyme suggested that H. iris, and O. rusticus enzymes shared similar primary/higher-order structure with H. discus enzyme, but the L. brevicula enzymes did not. H. discus, H. iris, and O. rusticus enzymes were classified to polysaccharide-lyase family-14 by the analysis of partial amino acid sequences, while the L. brevicula enzymes were not.
• Preparation of beta-1,3-glucanase from scallop mid-gut gland drips and its use for production of novel heterooligosaccharides

  Yuya Kumagai, Akira Inoue, Hiroyuki Tanaka, Takao Ojima

  FISHERIES SCIENCE 74 (5) 1127 - 1136 0919-9268 2008/10 [Refereed][Not invited]
   

  The mid-gut gland of scallop Patinopecten yessoensis has been discarded in scallop processing factories as a fishery waste and various attempts have been made to turn the waste into valuable resources. In the present study, we tried to use mid-gut gland drips from scallop as a source of beta-1,3-glucanase. The mid-gut gland drips were collected in a local fishery factory in Yubetsu-cho, Hokkaido Prefecture. beta-1,3-Glucanase was purified from the mid-gut gland drips by ammonium sulfate fractionation followed by successive chromatography on Toyopearl Phenyl-650M and Toyopearl DEAE-650M. The scallop beta-1,3-glucanase, named PyLam38 in the present study, showed a molecular mass of approximately 38 kDa by sodium dodecylsulfate-polyacrylamide gel electrophoresis, and hydrolyzed laminarin, a beta-1,3-glucan from Laminaria sp., producing laminaribiose and glucose with an optimal pH and temperature of 6.0 and 45 degrees C, respectively. PyLam38 exhibited high transglycosylation activity toward various accepter substrates such as monosaccharides, alcohols and xylooligosaccharides. Thus, PyLam38 was found to be useful for the production of various novel heterooligosaccharides consisting of laminarioligosaccharides and various accepters.
• Isolation and primary structure of a cellulase from the Japanese sea urchin Strongylocentrotus nudus

  Yukiko Nishida, Ken-ichi Suzuki, Yuya Kumagai, Hiroyuki Tanaka, Akira Inoue, Takao Ojima

  BIOCHIMIE 89 (8) 1002 - 1011 0300-9084 2007/08 [Refereed][Not invited]
   

  Glycoside-hydrolase-family 9 (GHF9) cellulases are known to be widely distributed in metazoa. These enzymes have been appreciably well investigated in protostome invertebrates such as arthropods, nematodes, and mollusks but have not been characterized in deuterostome invertebrates such as sea squirts and sea urchins. In the present study, we isolated the cellulase from the Japanese purple sea urchin Strongylocentrotus nudus and determined its enzymatic properties and primary structure. The sea urchin enzyme was extracted from the acetone-dried powder of digestive tract of S. nudus and purified by conventional chromatographies. The purified enzyme, which we named SnEG54, showed a molecular mass of 54 kDa on SDS-PAGE and exhibited high hydrolytic activity toward carboxymethyl cellulose with an optimum temperature and pH at 35 degrees C and 6.5, respectively. SnEG54 degraded cellulose polymer and cellooligosaccharides larger than cellotriose producing cellotriose and cellobiose but not these small cellooligosaccharides. From a cDNA library of the digestive tract we cloned 1822-bp cDNA encoding the amino-acid sequence of 444 residues of SnEG54. This sequence showed 50-57% identity with the sequences of GHF9 cellulases from abalone, sea squirt, and termite. The amino-acid residues crucial for the catalytic action of GHF9 cellulases are completely conserved in the SnEG54 sequence. An 8-kbp structural gene fragment encoding SnEG54 was amplified by PCR from chromosomal DNA of S. nudus. The positions of five introns are consistent with those in other animal GHF9 cellulase genes. Thus, we confirmed that the sea urchin produces an active GHF9 cellulase closely related to other animal cellulases. (c) 2007 Elsevier Masson SAS. All rights reserved.

MISC

• 海洋深層水を活用した海藻スプラウトの陸上養殖と利用適性に関する研究

  木下康宣, 木村和世, 川越力, 高野智宏, 熊谷祐也, 岸村栄毅, 宇治利樹, 水田浩之  北海道立工業技術センター研究成果発表会要旨集(Web)  2021-  2021
• デキストランデキストリナーゼの多糖合成に関与するアミノ酸の同定

  佐々木優希, 熊谷祐也, 貞廣樹里, LANG Weeranuch, 田上貴祥, 奥山正幸, 木村淳夫  日本農芸化学会大会講演要旨集(Web)  2018-  ROMBUNNO.2A26p03 (WEB ONLY)  2018/03/05  [Not refereed][Not invited]
  
• Bacillus sp.AHU2001由来GH31α‐グルコシダーゼの生化学的諸性質と基質認識に重要な構造因子の解析

  佐分利亘, 奥山正幸, 熊谷祐也, 木村淳夫, 森春英  日本農芸化学会大会講演要旨集(Web)  2015-  3E32P02 (WEB ONLY)  2015/03/05  [Not refereed][Not invited]
  
• Bp-6 Amphiphilic function of linear-isomaltomegalosaccharides (L-IMS) on ethyl red (ER) solubility

  Lang Weeranuch, Kumagai Yuya, Sadahiro Juri, Okuyama Masayuki, Mori Haruhide, Sakairi Nobuo, Kimura Atsuo  Bulletin of applied glycoscience  4-  (3)  B42  2014/08/20
• Ba-3 Dextran dextrinaseのPhe602の生成物特異性に関する影響(その他の糖質関連酵素,一般講演,日本応用糖質科学会平成26年度大会(第63回))

  坂谷 敦, 熊谷 祐也, 貞廣 樹里, Weeranuch Lang, 奥山 正幸, 森 春英, 木村 淳夫  応用糖質科学：日本応用糖質科学会誌  4-  (3)  B39  2014  [Not refereed][Not invited]
  
• Da-6 放線菌マンナナーゼの基質特異性に関するループ7の解析(ヘミセルラーゼ,一般講演,日本応用糖質科学会平成26年度大会(第63回))

  熊谷 祐也, 裏地 美杉, 奥山 正幸, 木村 淳夫, 畑中 唯史  応用糖質科学：日本応用糖質科学会誌  4-  (3)  B53  2014  [Not refereed][Not invited]
  
• 2P-052 Insight into the substrate specificity of galactosylmannooligosaccharide by actinomycete mannanase

  Kumagai Yuya, Uraji Misugi, Okuyama Masayuki, Kimura Atsuo, Hatanaka Tadashi  日本生物工学会大会講演要旨集  66-  119  -119  2014  [Not refereed][Not invited]
  
• Da-10 Gluconobacter oxydans由来dextran dextrinaseによる直鎖イソマルトメガロ糖の酵素合成(糖質の合成・生産,一般講演,日本応用糖質科学会平成25年度大会(第62回))

  熊谷 祐也, Lang Weeranuch, 貞廣 樹里, 奥山 正幸, 森 春英, 木村 淳夫  応用糖質科学：日本応用糖質科学会誌  3-  (3)  B46  2013  [Not refereed][Not invited]
  
• 1Ep10 Inhibitory Action of Xaa-Pro Dipeptides toward Human Dipeptidyl Peptidase IV

  Hatanaka Tadashi, Kumagai Yuya, Usuki Hirokazu, Kawakami Kayoko, Mukaihara Takafumi  日本生物工学会大会講演要旨集  63-  41  -41  2011  [Not refereed][Not invited]
  
• Comparative study on general properties of alginate lyases from some marine gastropod mollusks

  RAHMAN Mohammad Matiur  日本水産學會誌 = Bulletin of the Japanese Society of Scientific Fisheries  76-  (4)  580  -580  2010/07/15  [Not refereed][Not invited]
  
• エゾアワビ肝膵臓におけるアルギン酸代謝に関する研究

  木本雄太, 熊谷祐也, 澤辺智雄, 田中啓之, 井上晶, 尾島孝男  日本水産学会大会講演要旨集  2010-  2010
• 2P-1071 Clarification of the reaction mechanism of aminolysin and its application into the effective synthesis of cyclic dipeptides

  Usuki Hirokazu, Yamamoto Yukihiro, Yamasato Akihiro, Kumagai Yuya, Mukaihara Takafumi, Hatanaka Tadashi  日本生物工学会大会講演要旨集  22-  26  -26  2010  [Not refereed][Not invited]
  
• 3P-1054 Analysis of Ca^<2+> dependent domain of mannanase from Streptomyces sp.

  KUMAGAI Yuya, USUKI Hirokazu, YAMAMOTO Yukihiro, YAMASATO Akihiro, MUKAIHARA Takafumi, HATANAKA Tadashi  日本生物工学会大会講演要旨集  22-  71  -71  2010  [Not refereed][Not invited]
  
• 3P-1158 Collagen degradation by combination of Streptomyces aminopeptidases

  HATANAKA Tadashi, USUKI Hirokazu, YAMAMOTO Yukihiro, KUMAGAI Yuya, YAMASATO Akihiro, MUKAIHARA Takafumi  日本生物工学会大会講演要旨集  22-  97  -97  2010  [Not refereed][Not invited]
  
• 海洋資源-7つの不思議と11の挑戦-, 大塚耕司編, 海事プレス社, 2007年, A5版, 196頁, 1,429円

  熊谷 祐也, 北大院  日本水産学会誌 = Bulletin of the Japanese Society of Scientific Fisheries  74-  (2)  2008/03/15  [Not refereed][Not invited]
  

Books etc

• Advances in Oligosaccharides and Polysaccharide Modifications in Marine Bioresources

  Yuya Kumagai, Hideki Kishimura, Benwei Zhu (Editor)
  Mdpi AG 2023/08 (ISBN: 3036583645) 176
• Marine_Bioactive_PeptidesStructure_Function_and_Application

  A.M.M.Martin, Y.Miyabe, T.Shimizu, W.Matsui, Y.Kumagai, H.Kishimura (Contributorpp.63-77)
  MDPI 2023/07 (ISBN: 9783036582603)
• Mycosporine-Like Amino Acids from Marine Resource

  Y. Nishida, Y. Kumagai, S. Michiba, H. Yasui, H. Kishimura (Joint workpp. 39-56)
  Marine Drugs, Multidiciplinary Digital Publishing Institute（MDPI） 2021/01

Presentations

• 真昆布から中間素材の調製とその特性  [Invited]

  馬場惇平, 菅原一真, 熊谷祐也, 岸村栄毅

  海藻活用研究会令和6年度定期総会シンポジウム  2024/06
• Mycosporine-like amino acids from red alga dulse (Devaleraea inkyukeei) harvested from two location in southern Hokkaido  [Not invited]

  Koki Takizawa, Soichiro Hakura, Yuya Kumagai, Hideki Kishimura

  KoSFoST 2024 (International Symposium and Annual Meeting)  2024/06
• Fucoidan from Kombu Saccharine japonica: separation by molecular weight  [Not invited]

  Jumpei Baba, Yuya Kumagai, Hideki Kishimura

  KoSFoST 2024 (International Symposium and Annual Meeting)  2024/06
• Function of underusage red alga dulse in Kombu cultivation rope  [Invited]

  Yuya Kumagai

  KoSFoST 2024 (International Symposium and Annual Meeting)  2024/06
• 函館産マコンブの多糖成分の機能性について  [Invited]

  熊谷祐也, 岸村栄毅

  海藻活用研究会 令和6年シンポジウム  2024/02
• 4種紅藻由来マイコスポリン様アミノ酸に関する研究  [Not invited]

  山本竜矢, 熊谷祐也, 岸村栄毅

  令和5年度 日本水産学会 北海道支部大会  2024/01
• 函館産マコンブ Saccharina japonica 由来多糖類の調製と その収量，組成及び抗酸化作用に関する研究  [Not invited]

  小島大樹, 今武洋人, 田畑大伍, 岸村栄毅, 熊谷祐也

  令和5年度 日本水産学会 北海道支部大会  2024/01
• 4種紅藻由来マイコスポリン様アミノ酸の 含有量及び組成の月別変動と抗酸化活性  [Not invited]

  山本竜矢, 熊谷祐也, 岸村栄毅

  2023年度 日本農芸化学会北海道支部 第２回学術講演会  2023/12
• 函館産マコンブ由来フコイダンの月別変動  [Not invited]

  馬場惇平, 熊谷祐也, 岸村栄毅

  2023年度 日本農芸化学会北海道支部 第２回学術講演会  2023/12
• Fucoidan from Kombu Saccharina japonica: Monthly variation and structure analysis  [Not invited]

  Jumpei Baba, Yuya Kumagai, Hideki Kishimura

  13th Joint International Symposium on Food Science and Technology Among NUS, TUMSAT, HU, and KU  2023/11
• Study on health functional components of seaweed  [Invited]

  Yuya Kumagai

  13th Joint International Symposium on Food Science and Technology Among NUS, TUMSAT, HU, and KU  2023/11
• 天然日焼け止め成分 「MAAs」含有量の変動を追え！  [Not invited]

  中目 凛, 森田理央, 瀧澤巧季, 山本竜矢, 熊谷祐也, 岸村栄毅

  HAKODATEアカデミックリンク2023  2023/11
• 劇場版 KOMBU×FAMILY CODE：Brown  [Not invited]

  濱崎海瑠, 馬場惇平, 張昕然, 濱崎海瑠, 田畑太伍, 熊谷祐也, 岸村栄毅

  HAKODATEアカデミックリンク2023  2023/11
• 水産廃棄物が可能にするサステイナブルな家畜生産への道 ：水産・獣医連携の秘める大きな可能性  [Not invited]

  辻井豪佑, 熊谷祐也, 中尾亮

  第6回 北大・部局横断シンポジウム  2023/10
• 函館産マコンブ由来フコイダンの月別変動 及び構造特性について  [Not invited]

  馬場惇平, 熊谷裕也, 岸村栄毅

  第6回 北大・部局横断シンポジウム  2023/10
• 真昆布からの中間素材の物性・機能性評価  [Invited]

  熊谷祐也, 岸村栄毅

  海藻活用研究会 令和5年度 総会  2023/06
• 紅藻ウミゾウメンの葉緑体DNAにコードされるタンパク質に由来するDPP-IV阻害ペプチドのin silico解析  [Not invited]

  Martin Alain Mune Mune, 陳 瑞郷, 熊谷祐也, 岸村栄毅

  第23回マリンバイオテクノロジー学会大会  2023/05
• Polysaccharides from brown algae: relationship between structure and function  [Invited]

  Yuya Kumagai, Hiroki Kojima, Jumpei Baba, Hideki Kishimura

  East Asia Fisheries Technologists Association (EAFTA) 2023  2023/05
• 函館産褐藻由来の多糖成分について  [Invited]

  岸村栄毅, 馬場惇平, 熊谷祐也

  海藻活用研究会 令和４年度定期シンポジウム  2023/03
• ビフィズス菌の増殖に適した 紅藻ダルス由来キシロオリゴ糖の組成  [Not invited]

  吉田光里, 熊谷祐也, 岸村栄毅

  日本水産学会 北海道支部大会  2022/11
• 函館産褐藻由来フコイダンの比較  [Not invited]

  馬場惇平, 熊谷祐也, 岸村栄毅

  日本水産学会 北海道支部大会  2022/11
• 紅藻ダルス由来のマイコスポリン様アミノ酸の 月別変動および効率的な抽出方法の検討  [Not invited]

  山本竜矢, 熊谷祐也, 岸村栄毅

  令和4年度 日本農芸化学会 北海道・東北合同支部会  2022/09
• 紅藻ダルス由来タンパク質のDPPⅣ阻害作用に関する研究  [Not invited]

  松井 亘, 熊谷祐也, 岸村栄毅

  令和4年度 日本農芸化学会 北海道・東北合同支部会  2022/09
• 紅藻ダルス由来キシランから亜臨界水を用いたオリゴ糖の調製に関する研究  [Not invited]

  辰巳幸彦, 熊谷祐也, Byung-Soo Chun, 岸村栄毅

  令和4年度 日本農芸化学会 北海道・東北合同支部会  2022/09
• 塩ストレスによる紅藻類の食味改善物質の同定と機構に関する研究  [Invited]

  熊谷 祐也

  公益財団法人ソルトサイエンス第34回助成研究発表会  2022/07
• 紅藻ツルシラモ由来フィコエリスロビリンの生合成に関わる酵素に関する研究  [Not invited]

  宮部好克, 熊谷祐也, 清水健志, 松井 亘, 佐藤諒介, 岸村栄毅

  第22回マリンバイオテクノロジー学会大会  2022/05
• 紅藻ツルシラモ由来フィコエリスリン・ガンマ鎖の構造特性  [Not invited]

  熊谷祐也, 宮部好克, 清水健志, 佐藤諒介, 岸村栄毅

  令和４年度日本水産学会春季大会  2022/03
• 紅藻類のマイコスポリン様アミノ酸の可能性

  岸村栄毅, 熊谷祐也, 木下康宣, 安井 肇, 川越 力

  海藻活用研究会定期シンポジウム 〜ウィズコロナの海藻活用〜  2022/02
• ダルスが腸に届くまで  [Not invited]

  辰巳幸彦, 松本晃帆, 吉田光里, 熊谷祐也, 岸村栄毅

  HAKODATEアカデミックリンク2021  2021/11
• 海藻のヌメヌメ成分「フコイダン」の最大Maxパワー力を生かすために

  伊藤大翔, 松井 亘, 熊谷祐也, 岸村栄毅

  HAKODATEアカデミクリンク2021  2021/11
• 季節変動から紐解くダルス「MAAs」産業利用への試み  [Not invited]

  山本竜矢, 前田侑也, 熊谷祐也, 岸村栄毅

  HAKODATEアカデミックリンク2021  2021/11
• 紅藻ツルシラモ由来フィコエリスリン の構造・機能特性  [Not invited]

  前田俊介, 熊谷侑貴, 宮部好克, 佐藤諒介, 熊谷祐也, 岸村栄毅

  令和3年度 日本水産学会秋季大会  2021/09
• 紅藻ダルス由来β-(1→3)/β-(1→4)キシランの 腸内細菌増殖作用の検討  [Not invited]

  吉田光里, 熊谷祐也, 岸村栄毅

  令和3年度 日本水産学会秋季大会  2021/09
• Vibrio由来glycoside hydrolase family 17 β-1,3-glucanaseの機能解析  [Not invited]

  熊谷祐也, 岸村栄毅

  令和3年度 日本水産学会秋季大会  2021/09
• 紅藻ダルス小形葉体の 栄養特性に関する研究  [Not invited]

  木下康宣, 鳥海 滋, 川越 力, 木村和世, 熊谷祐也, 岸村栄毅

  日本応用藻類学会 第19回大会  2021/09
• 紅藻ウミゾウメン葉緑体DNAにコードされるタンパク質由来ACE阻害ペプチドのin silico解析  [Not invited]

  陳 瑞卿, 丁 佳琦, 水田浩之, 熊谷祐也, 岸村栄毅

  2021年度 日本農芸化学会北海道支部 第1 回学術講演会  2021/07
• 海洋深層水を活用した海藻スプラウトの 陸上養殖と利用適性に関する研究  [Not invited]

  木下康宣, 木村和世, 川越 力, 高野智宏, 熊谷祐也, 岸村栄毅, 宇治利樹, 水田浩之

  2021年度 北海道立坑業技術センター研究成果発表会  2021/06
• Bifidobacterium adolescentisによるβ-(1→3)-キシロシル-キシロビオース分解機構の解明  [Not invited]

  小林真奈美, 熊谷祐也, 岸村栄毅

  R2年度 日本応用糖質科学会 北海道支部 支部賞授賞式・受賞公演およびシンポジウム  2021/01
• 紅藻ダルス由来β-(1→3)/β-(1→4)-キシロオリゴ糖調製法の開発およびエンド型キシラナーゼの基質特異性  [Not invited]

  藤井勇樹, 熊谷祐也, 岸村栄毅, 畑中 唯史

  R2年度 日本応用糖質科学会 北海道支部 支部賞授賞式・受賞公演およびシンポジウム  2021/01
• 人類を紫外線から守る海藻？！ 函館産紅藻に秘めたるMAAsのポテンシャル  [Not invited]

  杉山佳奈海, 西田有輝, 熊谷祐也, 岸村栄毅

  HAKODATEアカデミックリンク2020  2020/11
• 絶対正義オリゴ糖～もっと海藻は輝ける～  [Not invited]

  吉田里光, 小林真奈美, 栗田大輝, 熊谷祐也, 岸村栄毅

  HAKODATEアカデミックリンク2020  2020/11
• 天然＆陸上栽培された紅藻成分の相違とは？  [Not invited]

  大井一真, 熊谷祐也, 岸村栄毅

  HAKODATEアカデミックリンク2020  2020/11
• 放線菌 Streptomyces thermogriseus エンド型キシラナーゼを用いた紅藻ダルス β(1-3/1-4)キシロオリゴ糖調製法の開発  [Not invited]

  藤井 勇樹, 熊谷 祐也, 岸村 栄毅, 畑中 唯史

  2020年度 日本農芸化学会北海道支部／日本栄養・食糧学会北海道支部 合同学術講演会  2020/12
• 岩のり製品由来タンパク質から調製したペプチドの ACE 阻害作用  [Not invited]

  森河理絵, 熊谷祐也, 岸村栄毅

  令和 2 年度日本水産学会 北海道支部大会  2020/12
• 紅藻ダルス由来キシランの簡易調製法の開発とその酵素分解物による Bifidobacterium の増殖  [Not invited]

  栗田大輝, 熊谷祐也, 安井 肇, 岸村栄毅

  令和 2 年度日本水産学会 北海道支部大会  2020/12
• Efficient Extraction and Monthly Variation of Mycosporine-like Amino Acids from Red Alga Dulse in Japan  [Not invited]

  Yuki Nishida, Yuya Kumagai, Shunta Michiba, Hajime Yasui, Hideki Kishimura

  Online International Symposium of FSMILE 2020 Current Trends on Food Processing, Safety and Nutrition  2020/11
• Healthy functional materials in red algae  [Invited]

  Yuya Kumagai, Manami Kobayashi, Hajime Yasui, Hideki Kishimura

  Online International Symposium of FSMILE 2020 Current Trends on Food Processing, Safety and Nutrition  2020/11
• 「海藻の秘密兵器！？「マイコスポリン様アミノ酸」  [Invited]

  西田有輝・熊谷祐也・岸村栄毅

  アイデアと街を繋ぎ函館の未来を創る 合同研究発表会  2020/02
• 紅藻に含まれる健康機能性成分  [Invited]

  熊谷祐也

  次世代食育のグローバル化フォーラム（FFSMILE2020）  2020/02
• A search for β-(1→3)/β-(1→4)-xylotriose degradation enzyme from Bifidobacterium adolescentis  [Not invited]

  Manami Kobayashi, Yuya Kumagai, Hideki Kishimura

  12th Joint International Symposium on Food Science and Technology among NUS, TUMSAT, HU, KU and ZGU  2019/12
• ボーっと海苔食べてると答えられない⁉「フィコビリタンパク質って？」  [Not invited]

  森河理絵, 澄川果奈, 熊谷祐也, 岸村栄毅

  HAKODATEアカデミックリンク2019  2019/11
• ナマコのヌメヌメ「フコイダン」  [Not invited]

  瀬能拓海, 栗田大輝, 熊谷祐也, 岸村栄毅

  HAKODATEアカデミックリンク2019  2019/11
• 最強のマースおにいさんはただひとり！オレだ！  [Not invited]

  西田有輝, 熊谷祐也, 岸村栄毅

  HAKODATEアカデミックリンク2019  2019/11
• 紅藻ウップルイノリのACE阻害ペプチドの探索  [Not invited]

  渡邊慧, 勝倉 智, 岡田千晃, 熊谷祐也, 岸村栄毅

  第5回 北海道大学部局横断シンポジウム  2019/11
• Bifidobacterium adolescentisのβ-(1→3)/β-(1→4)-キシロトリオース分解機構に関する研究  [Not invited]

  小林真奈美, 熊谷祐也, 岸村栄毅

  第5回 北海道大学部局横断シンポジウム  2019/11
• 紅藻ダルスの糖質成分の活用について  [Invited]

  熊谷祐也

  海藻活用研究会 第3回定期シンポジウム  2019/07
• 紅藻ダルス由来β-(1→3)/β-(1→4)-キシロトリオースの Bifidobacterium属細菌選択増殖作用の検討  [Not invited]

  山本陽平, 小林真奈美, 熊谷祐也, 山崎浩司, 安井 肇, 尾島孝男, 岸村栄毅

  平成31年度日本水産学会春季大会  2019/03
• 函館産紅藻ダルス由来マイコスポリン様アミノ酸の 熱安定性および機能性  [Not invited]

  道場俊太, 木下康宜, 安井 肇, 熊谷祐也, 岸村栄毅

  平成31年度日本水産学会春季大会  2019/03
• 紅藻ダルスのタンパク質に含まれる機能性ペプチドの探索  [Not invited]

  熊谷祐也, 岸村栄毅

  第4回 北大・部局横断シンポジウム  2019/01
• 函館産ダルス由来マイコスポリン様アミノ酸の 含有量・組成の時期変動及び安定性に関する検討  [Not invited]

  道場俊太, 武田朋之, 木下康宣, 安井 肇, 栗原秀幸, 熊谷祐也, 岸村栄毅

  日本食品科学工学会 北海道支部大会  2018/12
• 実はこんなにすごい！！ スーパーフード "ダルス"  [Invited]

  栗田大輝, 熊谷祐也, 岸村栄毅

  合同研究発表会 シエスタハコダテ編 ademikku〜HAKODATEアカデミックリンク2018連携〜 アイデアと街を繋ぎ箱館の未来を創る  2018/11
• 実はこんなにすごい！！ スーパーフード "ダルス"  [Not invited]

  栗田大輝, 熊谷祐也, 岸村栄毅

  HAKODATEアカデミックリンク2018  2018/11
• 紅藻"ダルス"は"第２のガゴメ"となりうるか  [Not invited]

  藤井勇樹, 熊谷祐也, 岸村栄毅

  HAKODATEアカデミックリンク2018  2018/11
• 絶対に捨てられない海藻がここにある  [Not invited]

  小林真奈美, 山本陽平, 熊谷祐也, 岸村栄毅

  HAKODATEアカデミックリンク2018  2018/11
• 紅藻の真価 〜北海道より〜  [Not invited]

  岸本堯大, 熊谷祐也, 岸村栄毅

  HAKODATEアカデミックリンク2018  2018/11

Teaching Experience

マリンバイオマスの探索と利用マリンバイオマスの探索と利用 Hokkaido University
魚をたべる魚をたべる Hokkaido University

Association Memberships

• 日本水産学会   日本生物工学会   日本農芸化学会   

Works

• 低利用資源・紅藻類からの抗酸化物質の調製

  岸村栄毅, 熊谷祐也 2023/01 - Today
• ガゴメのサンプル処理

  岸村栄毅, 熊谷祐也 2022/05 - Today
• 紅藻ウップルイノリ・タンパク質に含まれる新規機能性ペプチドの同定

  岸村栄毅, 熊谷祐也 2022/05 - Today
• 低利用資源・紅藻から紫外線防御物質の調製法の開発

  岸村栄毅, 熊谷祐也 2022/05 - Today
• 未利用資源紅藻ダルスとその有効活用に向けて

  岸村栄毅, 熊谷祐也 2022/05 - Today
• ダルスの採集

  岸村栄毅, 熊谷祐也 2022/03 - Today
• ワカメの採集

  岸村栄毅, 熊谷祐也 2022/03 - Today
• 生産プロセス工学実習（連続蒸留理論・冷凍工学理論）【実験動画】

  岸村栄毅, 熊谷祐也 LASBOS Moodle 2021/10 - Today
• 低利用資源・紅藻から新たなオリゴ糖調製法の開発2

  岸村栄毅, 熊谷祐也 LASBOS Moodle 2021/10 - Today
• アカデミックリンク2020・紅藻ダルスへの質問・ご意見

  熊谷祐也 LASBOS Moodle 2021/10 - Today
• Search for health functional ingredients in red algae, a low-use resource; protein and peptide

  Hideki Kishimura, Yuya Kumagai LASBOS Moodle 2021/10 - Today
• Search for health functional ingredients in red algae, a low-use resource; a method for preparing new oligosaccharides

  Hideki Kishimura, Yuya Kumagai LASBOS Moodle 2021/10 - Today
• Genome analysis of mitochondria and chloroplast from red alga dulse and the relation of bioactivity

  Hideki Kishimura, Yuya Kumagai LASBOS Moodle 2021/10 - Today

Research Projects

• ホタテガイ外套膜ペプチドの定量技術に関する研究

  Date (from‐to) : 2021/09 -2022/03 

  Author : 岸村栄毅, 熊谷祐也
• 陸上栽培による 海藻 の次世代タンパク質化および高機能 性 評価システムの構築

  Date (from‐to) : 2021/04 -2022/03 

  Author : 熊谷祐也, 川越 力, 岸村栄毅, 木下康宣, 鳥海 滋
• 塩ストレスによる紅藻類の食味改善物質の同定と機構に関する研究

  Date (from‐to) : 2021/04 -2022/03 

  Author : 熊谷祐也, 岸村栄毅, 川越 力
• 北方系紅藻の陸上栽培に関する研究事業

  Date (from‐to) : 2021/04 -2022/03 

  Author : 熊谷祐也, 岸村栄毅, 川越 力, 木下康宣, 鳥海 滋
• 紫外線防御物質に着目したナマコ種苗の育成および飼料改善

  Date (from‐to) : 2020/04 -2021/03
• HU-NUS summer course “Seafood supply chains in Singapore and Japan”

  Date (from‐to) : 2019/04 -2021/03 

  Author : 岸村栄毅, ジョンバウアー, 熊谷祐也
• ホタテガイペプチドを用いたサケ科魚類養殖魚の質的向上に関する研究

  Date (from‐to) : 2019/08 -2020/03 

  Author : 岸村栄毅, 熊谷祐也
• 北方系海藻の通年収穫を目的とした陸上栽培技術の開発

  ノーステック財団：「研究開発助成事業」 スタートアップ研究補助金

  Date (from‐to) : 2019/08 -2020/03 

  Author : 川越 力
• 認知症予防の「二つの作用点」に「一つの食材」でアプローチする

  ノーステック財団：「札幌ライフサイエンス産業活性化事業」 事業化支援補助金

  Date (from‐to) : 2019/07 -2020/03 

  Author : 岸村栄毅
• 紅藻澱粉の構造解析と食品中における機能性の 解明

  公益財団法人・飯島藤十郎記念食品科学振興財団：学術研究助成

  Date (from‐to) : 2019/04 -2020/03 

  Author : 熊谷祐也
• 水産軟体動物における２段階の海藻資化戦略：自然免疫賦活化とエネルギー獲得

  日本学術振興会：科学研究費助成事業

  Date (from‐to) : 2016/04 -2018/03 

  Author : 熊谷 祐也

   

  本研究は水産軟体動物が海藻多糖をどのように資化するのかを明らかにすることを目的としている。その中でもラミナリンは自然免疫を賦活化する糖質であるが、それらはβ-(1→3)-グリコシド結合から成るもので構成糖はエネルギー源となるグルコースである。そのため、水産軟体動物がラミナリンをエネルギー源としてみなしているのか、または自然免疫を賦活化するものとして利用しているかのという疑問を明らかにするものである。本研究は水産軟体動物の生化学的な特性を明らかにするだけでなく、水産養殖において病気などの問題解決の糸口にもつながる研究であり凡庸性が高いものである。 本研究の核となるのがラミナリンを分解する酵素群ラミナリナーゼであり、これには独特なドメインを持つことが明らかとなり、それらの働きがラミナリンをエネルギー源としての利用または自然免疫賦活化する物質として利用しているかを制御していると考えられたため、その機能解析を行った。これまでに本ドメインは海藻多糖の成分に結合能を示すことを明らかとしたが、どの糖質に親和性を示すのか明らかでなかった。詳細な検討の結果、本ドメインはアルギン酸などの酸性多糖に結合することが明らかとなった。ここではそれに対する結合の強さを明らかとした。可溶性糖質とタンパク質の結合力の測定はアフィニティーゲル、表面プラズモン共鳴、等温滴定型カロリメトリーにより評価した。その結果、表面プラズモン共鳴でその結合力を評価することができ、2×10-8 （Ｍ）の解離定数を求めることができた。また本ドメインは塩により結合能が異なる。その評価についても本装置を用いることで測定が可能であることが分かった。
• Elucidation of biologically active laminarin-structure and development of its enzymatic evaluation method

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research

  Date (from‐to) : 2014/04 -2016/03 

  Author : Kumagai Yuya

   

  Laminarin has biologically active saccharides such as the immunostimulation and antitumor activiy. The laminarin structure differes from spicies, indicating that the relationship of the structures and the expression mechanism of bioactivities is still unclear. In this study, we employed glucanase with a limited hydrolysis activity toward laminarin and attempted for oligosaccharide production. The enzyme produced biologically active oligosaccharides and revealed the hydrolysis pattern of biologically active laminarin.

Industrial Property Rights

• 特許WO/2021/070549:コムギのゲノム編集方法、及びその利用  

  柳楽洋三, 濱田晴康, 三木隆二, 田岡直明, 今井亮三, 熊谷祐也

Social Contribution

• 令和4年度 公益社団法人日本農芸化学会 北海道・東北支部合同若手の会

  Date (from-to) : 2022/09/20-2022/09/21

  Role : Organizing member

  Sponser, Organizer, Publisher  : 公益社団法人日本農芸化学会 北海道支部
• Reviewer Certificate

  Date (from-to) : 2022/06

  Role : Organizing member

  Sponser, Organizer, Publisher  : 日本水産学会誌・FISHERIES SCIENCE
• Reviewer Certificate

  Date (from-to) : 2020/09/10

  Role : Organizing member

  Sponser, Organizer, Publisher  : MDPI・Molecules
• Reviewer Certificate

  Date (from-to) : 2020/06/28

  Role : Organizing member

  Sponser, Organizer, Publisher  : ELSEVIER・Carbohydrate Research
• Reviewer Certificate

  Date (from-to) : 2019/09/29

  Role : Organizing member

  Sponser, Organizer, Publisher  : MDPI・Marine Drugs
• Reviewer Certificate

  Date (from-to) : 2019/09/11

  Role : Organizing member

  Sponser, Organizer, Publisher  : Springer・Fishries Science
• 海藻の光る成分を調べてみよう！

  Date (from-to) : 2019/08/05

  Role : Lecturer

  Sponser, Organizer, Publisher  : 北海道大学大学院水産科学研究院 2019

  Event, Program, Title : 北海道大学水産学部オープンキャンパス 2019年
• Reviewer Certificate

  Date (from-to) : 2019/07/19

  Role : Organizing member

  Sponser, Organizer, Publisher  : ELSEVIER・Biochimie
• Reviewer Certificate

  Date (from-to) : 2019/07/18

  Role : Organizing member

  Sponser, Organizer, Publisher  : MDPI・Marine Drugs
• Reviewer Certificate

  Date (from-to) : 2019/06/10

  Role : Organizing member

  Sponser, Organizer, Publisher  : J-Stage・Bioscience, Biotechnology, and Biochemistry

Media Coverage

• 海藻「ダルス」活用模索 コンブ養殖の厄介者 血糖値抑える糖質生成

  Date : 2024/08

  Publisher, broadcasting station: 北海道新聞

  Program, newspaper magazine: 北海道新聞

  Paper
• 水産学部とシンガポール国立大学のサマーコースの取組みが北海道新聞に掲載されました

  Date : 2024/06

  Publisher, broadcasting station: 北海道大学ホームページ

  Program, newspaper magazine: 北海道大学ホームページ

  プレスリリース Internet
• 色落ちした紅藻"ダルス"から血糖抑制が期待されるオリゴ糖を調製～低利用資源の有効活用への貢献に期待～

  Date : 2024/05

  Publisher, broadcasting station: 北海道大学ホームページ

  Program, newspaper magazine: 北海道大学ホームページ

  プレスリリース Internet
• 低利用資源の紅藻"ダルス"から紫外線防御物質MAAs調製法を確立 ～効率的な調製法を検討、異なる条件で含有量と組成を比較～

  Date : 2023/10

  Publisher, broadcasting station: 北海道大学ホームページ

  Program, newspaper magazine: 北海道大学ホームページ

  プレスリリース Internet
• 北海道大学－シンガポール国立大学 サマーコース ～日本とシンガポールにおける水産物供給体制の比較～

  Date : 2020/06

  Publisher, broadcasting station: 北海道大学 教育改革室

  Program, newspaper magazine: 北海道大学における教育方法のグッド・プラクティス

  Pr