Jan. 2024, 公益社団法人 日本水産学会, 日本水産学会 令和5年度北海道支部大会 最優秀講演賞（発表者）
腸炎ビブリオに感染するバクテリオファージVF16 の性状
三浦太暉;⼭⽊将悟;⽥渕いつき;⼭﨑浩司;川合祐史, 44512735

Nov. 2023, Japan Canners Association, Henmi Award
Inhibition of Morganella morganii growth and histamine production using a bacteriophage cocktail
Shogo Yamaki;Aoi Sakanoue;Kosuke Arai;Koji Yamazaki;Yuji Kawai, Japan society, Japan, 28657562

Aug. 2023, The Japanese Society for Food Science and Technology, Food Science and Technology Research Award Vol. 28
Inhibition of Morganella morganii growth and histamine production using a bacteriophage cocktail
Shogo Yamaki;Aoi Sakanoue;Kosuke Arai;Koji Yamazaki;Yuji Kawai, Japan, 28657562

May 2022, The Society for Antibacterial and Antifungal Agents, Japan, 令和3年度 日本防菌防黴学会 論文賞（共著者）　　　　　　　　　　　　　　　
Spore heat resistance and growth ability at refrigeration temperatures of Bacillus spp. and Paenibacillus spp.
小林哲也;東考憲;八十川大輔;山木将悟;山﨑浩司, Official journal, Japan

Sep. 2018, Japanese Society of Food Microbiology, Japanese Journal of Food Microbiology 2017 Best Paper Award　　　　　　　　　　　　　　　
Distribution of fishery products and histamine producing ability of Morganella psychrotolerans, a psychrotrophic histamine-producing bacterium.
Riko Kato;Di Wang;Shogo Yamaki;Yuji Kawai;Koji Yamazaki

Mar. 2017, 北海道大学大学院水産科学院, 伊藤一隆賞　　　　　　　　　　　　　　　

Aug. 2015, 日本食品科学工学会, 第11回若手の会 優秀ポスター企業賞　　　　　　　　　　　　　　　
広宿主域を示すPhotobacterium damselae subsp. damselae溶菌バクテリオファージの探索とその性状
山木将悟;黒沼宗弥;久保田光矢;川合祐史;山崎浩司

Proposed approach for determining minimal pasteurization conditions for refrigerated processed foods by combined challenge tests and probabilistic analysis
Tetsuya Kobayashi, Kento Koyama, Ryuichi Tsutsumi, Shogo Yamaki, Koji Yamazaki
Food Science and Technology Research, 32, 1, 91, 100, Japanese Society for Food Science and Technology, Jan. 2026, [Peer-reviewed], [International Magazine]
English, Scientific journal

Combination of a novel bacteriophage and d-serine effectively controls Vibrio parahaemolyticus growth in seafood
Daiki Miura, Shogo Yamaki, Itsuki Tabuchi, Yuji Kawai, Koji Yamazaki
Applied Food Research, 4, 2, 100558, Elsevier BV, Dec. 2024, [Peer-reviewed], [Corresponding author], [International Magazine]
English, Scientific journal, 44512735

Hydrogenimonas leucolamina sp. nov., a hydrogen- and sulphur-oxidizing mesophilic chemolithoautotroph isolated from a deep-sea hydrothermal vent chimney at the Suiyo Seamount in the Western Pacific Ocean
Shuya Hatakeyama, Sayaka Mino, Mana Mizobata, Mako Takada, Jiro Tsuchiya, Shogo Yamaki, Yasuhiro Ando, Tomoo Sawabe, Ken Takai
International Journal of Systematic and Evolutionary Microbiology, 74, 10, 006553, Microbiology Society, 22 Oct. 2024, [Peer-reviewed], [International Magazine]
English, Scientific journal, A novel mesophilic bacterium, strain SS33^T, was isolated from a deep-sea hydrothermal vent chimney at Suiyo Seamount, Izu-Bonin Arc, Western Pacific Ocean. The cells of strain SS33^T were motile short rods with a single polar flagellum. The growth of strain SS33^T was observed at the temperature range between 33 and 55 °C (optimum growth at 45 °C), at the pH range between 5.0 and 7.1 (optimum growth at pH 6.0) and in the presence of between 2.0 and 4.5% (w/v) NaCl [optimum growth at 3.5% (w/v)]. Strain SS33^T was a facultative anaerobic chemolithoautotroph using molecular hydrogen and elemental sulphur as the sole electron donor. Nitrate, nitrous oxide, sulphate, elemental sulphur and molecular oxygen were capable of serving as the sole electron acceptor. Phylogenetic analysis based on 16S rRNA gene sequences placed strain SS33^T in the genus Hydrogenimonas belonging to the class Epsilonproteobacteria. The closely related species of strain SS33^T were Hydrogenimonas urashimensis SSM-Sur55^T (95.96%), Hydrogenimonas thermophila EP1-55-1%^T (95.75%) and Hydrogenimonas cancrithermarum ISO32^T (95.24%). According to the taxonomic and physiological characteristics, it is proposed that strain SS33^T was classified into a novel species of genus Hydrogenimonas, Hydrogenimonas leucolamina sp. nov., with SS33^T (=JCM 39184^T =KCTC 25253^T) as the type strain. Furthermore, the genome comparison of Epsilonproteobacteria revealed that their [NiFe] hydrogenase genes belonging to Group 1b could be divided into two phylogenetic lineages and suggested that the reverse gyrase gene has been lost after division to the genus Hydrogenimonas.

Biological characterization and genomic analysis of a novel bacteriophage, MopsHU1, infecting Morganella psychrotolerans
Shogo Yamaki, Koji Yamazaki
Archives of Virology, 169, 9, 182, Springer Science and Business Media LLC, 17 Aug. 2024, [Peer-reviewed], [Lead author, Corresponding author], [International Magazine]
English, Scientific journal, 28657562

The Description of Pseudoalteromonas apostichopi sp. nov., Vibrio apostichopi sp. nov., and Marinobacter apostichopi sp. nov. from the Fertilized Eggs and Larvae of Apostichopus japonicus
Rika Kudo, Ryota Yamano, Juanwen Yu, Shuya Hatakeyama, Chunqi Jiang, Sayaka Mino, Shogo Yamaki, Yasuhiro Ando, Yuichi Sakai, Tomoo Sawabe
Current Microbiology, 81, 8, 246, Springer Science and Business Media LLC, 28 Jun. 2024, [Peer-reviewed], [International Magazine]
English, Scientific journal

Hydrogenimonas cancrithermarum sp. nov., a hydrogen- and thiosulfate-oxidizing mesophilic chemolithoautotroph isolated from diffuse-flow fluids on the East Pacific Rise, and an emended description of the genus Hydrogenimonas
Sayaka Mino, So Fukazawa, Jiro Tsuchiya, Jesse C. McNichol, Stefan M. Sievert, Shogo Yamaki, Yasuhiro Ando, Tomoo Sawabe
International Journal of Systematic and Evolutionary Microbiology, 73, 11, 006132, Microbiology Society, 03 Nov. 2023, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
English, Scientific journal, A novel mesophilic, hydrogen- and thiosulfate-oxidizing bacterium, strain ISO32^T, was isolated from diffuse-flow hydrothermal fluids from the Crab Spa vent on the East Pacific Rise. Cells of ISO32^T were rods, being motile by means of a single polar flagellum. The isolate grew at a temperature range between 30 and 55 °C (optimum, 43 °C), at a pH range between 5.3 and 7.6 (optimum, pH 5.8) and in the presence of 2.0–4.0 % NaCl (optimum, 2.5 %). The isolate was able to grow chemolithoautotrophically with molecular hydrogen, thiosulfate or elemental sulfur as the sole electron donor. Thiosulfate, elemental sulfur, nitrate and molecular oxygen were each used as a sole electron acceptor. Phylogenetic analysis of 16S rRNA gene sequences placed ISO32^T in the genus Hydrogenimonas of the class Epsilonproteobacteria, with Hydrogenimonas thermophila EP1-55–1 %^T as its closest relative (95.95 % similarity). On the basis of the phylogenetic, physiological and genomic characteristics, it is proposed that the organism represents a novel species within the genus Hydrogenimonas, Hydrogenimonas cancrithermarum sp. nov. The type strain is ISO32^T (=JCM 39185^T =KCTC 25252^T). Furthermore, the genomic properties of members of the genus Hydrogenimonas are distinguished from those of members of other thermophilic genera in the orders Campylobacterales (Nitratiruptor and Nitrosophilus) and Nautiliales (Caminibacter, Nautilia and Lebetimonas), with larger genome sizes and lower 16S rRNA G+C content values. Comprehensive metabolic comparisons based on genomes revealed that genes responsible for the Pta–AckA pathway were observed exclusively in members of mesophilic genera in the order Campylobacterales and of the genus Hydrogenimonas. Our results indicate that the genus Hydrogenimonas contributes to elucidating the evolutionary history of Epsilonproteobacteria in terms of metabolism and transition from a thermophilic to a mesophilic lifestyle.

Antimicrobial activity and mechanism of action of oregano essential oil against Morganella psychrotolerans and potential application in tuna
Di Wang, Chunsheng Li, Chuang Pan, Yueqi Wang, Huan Xiang, Yang Feng, Xianqing Yang, Shengjun Chen, Yongqiang Zhao, Yanyan Wu, Laihao Li, Yuji Kawai, Koji Yamazaki, Shogo Yamaki
LWT, 165, 113758, 113758, Elsevier BV, Aug. 2022, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
English, Scientific journal

Broad host range bacteriophage, EscoHU1, infecting Escherichia coli O157:H7 and Salmonella enterica: Characterization, comparative genomics, and applications in food safety
Shogo Yamaki, Koji Yamazaki, Yuji Kawai
International Journal of Food Microbiology, 372, 109680, 109680, Elsevier BV, Jul. 2022, [Peer-reviewed], [Lead author, Corresponding author], [International Magazine]
English, Scientific journal, 28656239

Inhibition of Morganella morganii growth and histamine production using a bacteriophage cocktail
Shogo Yamaki, Aoi Sakanoue, Kosuke Arai, Koji Yamazaki, Yuji Kawai
Food Science and Technology Research, 28, 6, 489, 499, 2022, [Peer-reviewed], [Lead author, Corresponding author]
English, Scientific journal, 28657562

Spore Heat Resistance and Growth Ability at Refrigeration Temperatures of Bacillus spp. and Paenibacillus spp.
Tetsuya Kobayashi, Takanori Azuma, Daisuke Yasokawa, Shogo Yamaki, Koji Yamazaki
Biocontrol Science, 26, 3, 147, 155, The Society for Antibacterial and Antifungal Agents, Japan, Sep. 2021, [Peer-reviewed], [Domestic magazines]
English, Scientific journal, In this study, spore heat resistance and growth ability at refrigeration temperatures of Bacillus spp. and Paenibacillus spp. were determined. The spore D90°C of 67.6% (23 of 34 strains) of Bacillus and 73.9% (17 of 23 strains) of Paenibacillus was less than 15 min. The growth abilities of both genera were equivalent at 10°C. However, 71.1% (32 of 45 strains) of Paenibacillus and only 6.3% (3 of 48 strains) of Bacillus cereus group could grow at 4°C. Eight B. cereus strains formed spores with higher heat resistance compared to the other Bacillus strains assessed; however, they did not grow at tempreratures below 10°C. Conversely, four Paenibacillus strains formed spores with heat resistance equivalent to that of the eight B. cereus strains and grew at 6°C or lower. In particular, Paenibacillus sp. JCM13343 formed the highest heat-resistant spores (D90°C = 136.1 min) and grew well at 4°C. These results indicate that Paenibacillus can grow in processed foods during refrigerated storage and has the potential to cause spoilage as well as Bacillus. Therefore, Paenibacillus should be considered as one of the targets for microbiological control in refrigerated processed foods.

Long filamentous state of Listeria monocytogenes induced by sublethal sodium chloride stress poses risk of rapid increase in colony-forming units
Shogo Yamaki, Yuji Kawai, Koji Yamazaki
Food Control, 124, 107860, Elsevier BV, 2021, [Peer-reviewed], [Lead author], [International Magazine]
English, Scientific journal

Development of a Novel Food Antimicrobial Technology: Application of Bacteriophages
Shogo Yamaki, Koji Yamazaki
Nippon Shokuhin Kagaku Kogaku Kaishi, 67, 10, 352, 359, Japanese Society for Food Science and Technology, 15 Oct. 2020, [Peer-reviewed], [Invited], [Lead author], [Domestic magazines]
Scientific journal

Sanitizing efficacy and antimicrobial mechanism of peracetic acid against histamine-producing bacterium, Morganella psychrotolerans
Di Wang, Shogo Yamaki, Yuji Kawai, Koji Yamazaki
LWT, 126, 109263, 109263, Elsevier {BV}, May 2020, [Peer-reviewed], [International Magazine]
English, Scientific journal

Inhibitory effect of a combination with novel jumbo bacteriophages ΦMV-1 and ΦMV-4 on Morganella morganii subsp. morganii growth and histamine accumulation
Shogo Yamaki, Soya Kuronuma, Yuji Kawai, Koji Yamazaki
International Journal of Food Microbiology, 317, 108457, 108457, Elsevier BV, Mar. 2020, [Peer-reviewed], [Lead author, Corresponding author], [International Magazine]
English, Scientific journal, 28656186

Histamine Production Behaviors of a Psychrotolerant Histamine-Producer, Morganella psychrotolerans, in Various Environmental Conditions
Di Wang, Shogo Yamaki, Yuji Kawai, Koji Yamazaki
Current Microbiology, 77, 3, 460, 467, Springer Science and Business Media {LLC}, Mar. 2020, [Peer-reviewed], [International Magazine]
English, Scientific journal

Histamine Food Poisoning Associated with Fisheries Products and Histamine-Producing Bacteria
Shogo Yamaki, Koji Yamazaki
Japanese Journal of Food Microbiology, 36, 2, 75, 83, Japanese Society of Food Microbiology, 30 Jun. 2019, [Peer-reviewed], [Invited], [Lead author], [Domestic magazines]
Japanese, Scientific journal

Biocontrol of Morganella morganii subsp. morganii and Histamine Accumulation in Tuna Meat by Treatment with a Lytic Bacteriophage
Shogo Yamaki, Yuji Kawai, Koji Yamazaki
Food Science and Technology Research, 24, 2, 329, 337, Japanese Society for Food Science and Technology, 2018, [Peer-reviewed], [Lead author, Corresponding author], [Domestic magazines]
English, Scientific journal, 28656186

Distribution on Fishery Products and Histamine Producing Ability of Morganella psychrotolerans, a Psychrotrophic Histamine-Producing Bacterium
Kato Riko, Wang Di, Yamaki Shogo, Kawai Yuji, Yamazaki Koji
Japanese Journal of Food Microbiology, 34, 3, 158, 165, 日本食品微生物学会, 2017, [Peer-reviewed], [Domestic magazines]
Japanese,

Morganella psychrotolerans is a novel psychrotrophic histamine producing bacterium and seems to cause histamine fish poisoning (scombroid poisoning). However, there is little information about the occurrence and histamine producing ability of this bacterium for food contamination. To elucidate the contamination status of M. psychrotolerans, we used an MPN-PCR method that can determine bacterial number more sensitive than a traditional plating method. Many kinds of fish samples purchased in Hokkaido and water samples collected in Hakodate area were used in this study. Eighty-five MPN-PCR positive samples were found in total 192 samples (44.3%) and thirty-seven strains of M. psychrotolerans were isolated from the positive samples. It suggests M. psychrotolerans is widely distributed in retail seafood product in Japan. Then the amounts of histamine produced by M. psychrotolerans isolates were investigated. All isolates produced more than 4,000 mg/L (4,000 ppm) of histamine after 48 h incubation at 25℃. Next, the growth and histamine production of M. psychrotolerans (JCM 16473^T, strain Mps. 3 from a horse mackerel sample) and Photobacterium phosphoreum NBRC 103031^T was compared in the liquid media containing 0.1 or 2.0% NaCl at 4℃. At 0.1% NaCl, histamine concentration produced by M. psychrotolerans was higher than that by P. phosphoreum. It indicates M. psychrotolerans will also become one of the important bacteria associated with histamine-poisoning at refrigeration temperature on seafood, as well as P. phosphoreum.

Suppression of Initial Adhesion and Biofilm Formation of Listeria monocytogenes by Nisin and Sucrose Fatty Acid Ester
Shogo Yamaki, Naho Hamada, Yuji Kawail, Koji Yamazaki
JOURNAL OF THE JAPANESE SOCIETY FOR FOOD SCIENCE AND TECHNOLOGY-NIPPON SHOKUHIN KAGAKU KOGAKU KAISHI, 64, 10, 493, 501, 2017, [Peer-reviewed], [Lead author], [Domestic magazines]
Japanese, Scientific journal

Combined Effect of Nisin and Commercial Pectin-hydrolysate Treatment on Survival and growth of Listeria monocytogenes in Soy-seasoned Salmon Roe Products
Shogo Yamaki, Shinya Shirahama, Tetsuya Kobayashi, Yuji Kawai, Koji Yamazaki
FOOD SCIENCE AND TECHNOLOGY RESEARCH, 21, 5, 751, 755, Sep. 2015, [Peer-reviewed], [Lead author], [Domestic magazines]
English, Scientific journal

Characterization of a novel bacteriophage, Phda1, infecting the histamine-producing Photobacterium damselae subsp damselae
S. Yamaki, Y. Kawai, K. Yamazaki
JOURNAL OF APPLIED MICROBIOLOGY, 118, 6, 1541, 1550, Jun. 2015, [Peer-reviewed], [Lead author], [International Magazine]
English, Scientific journal

Characterization of a novel Morganella morganii bacteriophage FSP1 isolated from river water
Shogo Yamaki, Takuo Omachi, Yuji Kawai, Koji Yamazaki
FEMS MICROBIOLOGY LETTERS, 359, 2, 166, 172, Oct. 2014, [Peer-reviewed], [Lead author], [International Magazine]
English, Scientific journal

International Association for Food Protection 2019 Annual Meeting
Shogo Yamaki, NIPPON SUISAN GAKKAISHI, 86, 1, 30, 30, 15 Jan. 2020
Japanese Society of Fisheries Science, Japanese

水産物における損傷菌-食品加工における損傷菌発生とその問題点　　　　　　　　　　　　　　　
山木 将悟, 山﨑 浩司, 日本防菌防黴学会誌, 47, 11, 467, 472, Nov. 2019, [Invited], [Domestic magazines]
Japanese

食品微生物制御におけるバクテリオファージの利用
山木 将悟, 山崎 浩司, New food industry = ニューフードインダストリー : 食品加工および資材の新知識, 59, 7, 15, 23, Jul. 2017, [Invited]
食品資材研究会, Japanese

Utilization of Bacteriocins to the Control of Microbial Growth in Food
山木 将悟, 山﨑 浩司, 日本醸造協会誌, 109, 9, 636, 642, Sep. 2014, [Invited]
近年，消費者は加熱・加工を極力控えた食品を好むようになっている。このような消費者のニーズに応えつつ食品の安全を担保することは至難の業である。そこで，著者らに食品保存料として世界で広く利用され，食品における食中毒リスクの低減と品質の向上に大きく寄与し，食品の味，香りに影響なく，ヒトの消化酵素により分解される安全な天然由来抗菌ペプチドのバクテリオシンの代表のNisin A，さらにはバクテリオシンと他の抗菌物質との組み合わせなどを解説いただいた。味噌には精製ナイシンとして，5mg/kgの使用が認可されているので，味噌業界の方はご一読いただきたい。, 日本醸造協会, Japanese

生食のはなし : リスクを知って、おいしく食べる
山木将悟, コラム「ヒスタミン食中毒」
朝倉書店, Apr. 2023, 9784254431308, ix, 147p, 100–101, Japanese, General book, [Contributor]

食品製造・検査における芽胞・損傷菌とその検出・制御技術　　　　　　　　　　　　　　　
山木将悟, 山﨑浩司, 第II編 損傷菌の検出と制御 第2章5-「リステリア損傷菌の発生と制御」
シーエムシー出版, May 2020, [Joint work]

Seafood Safety and Quality - Chapter 5　　　　　　　　　　　　　　　
Koji Yamazaki, Shogo Yamaki, Dominic Kasujja Bagenda, Chapter 5 - Control of pathogens and spoilage bacteria on seafood products
CRC Press, Sep. 2018, [Joint work]

Seafood Safety and Quality - Chapter 3　　　　　　　　　　　　　　　
Shogo Yamaki, Koji Yamazaki, Chapter 3 - Foodborne pathogens related to seafood products
CRC Press, Sep. 2018, [Joint work]

Histamine poisonings by histamine-producing bacteria
LASBOS Moodle, Shogo Yamaki, 10 Feb. 2021 - Present, [Educational materials]

腸炎ビブリオとファージの共進化的軍拡競争：より強力なファージの作出と応用
科学研究費助成事業
Apr. 2025 - Mar. 2030
山木 将悟
日本学術振興会, 基盤研究(B), 北海道大学, Principal investigator, 25K00091

腸炎ビブリオファージの多様な宿主認識機構：腸炎ビブリオ制御への展開
科学研究費助成事業
Apr. 2022 - Mar. 2026
山木 将悟
腸炎ビブリオは水産物を汚染する食中毒細菌である。本菌は海水や水産物に広く分布しており，低温管理から逸脱した水産物の生食などにより食中毒の原因となる。近年，食中毒細菌の制御を目的として細菌に感染するウイルスであるバクテリオファージ（ファージ）を利用した微生物制御手法が注目されている。本研究では，腸炎ビブリオに感染するファージを分離し，その宿主特異性に関して明らかにした上で，腸炎ビブリオファージを利用した腸炎ビブリオの制御手法を構築することを目的として研究を行った。
令和4年度は，腸炎ビブリオファージの分離に取り組み，複数の腸炎ビブリオファージの分離に成功した。分離ファージの中から，様々な腸炎ビブリオの菌株に対してプラークを形成するファージVF-16を選抜し，一段増殖実験や吸着動態の観察，透過型電子顕微鏡によるファージの形態観察などを行なった。腸炎ビブリオファージVF-16は非収縮性の長い尾部を持つ（siphovirus）ファージであり，迅速に宿主細胞へと吸着することが明らかとなった。さらに，VF-16の増殖には，培地へのカルシウムイオンやマグネシウムイオンの添加が必要であり，腸炎ビブリオの増殖を阻害するためにはVF-16と二価カチオンを併用する必要があると推察された。実際に，カルシウムイオンとマグネシウムイオンを添加した液体培地で腸炎ビブリオの増殖抑制能を調べた結果，VF-16添加区ではVF-16未添加区と比べて腸炎ビブリオの増殖が大きく抑制された。
以上のように，令和4年度は腸炎ビブリオに感染するファージを複数分離するとともに，そのうち一株のVF-16を用いて，腸炎ビブリオファージが腸炎ビブリオの増殖抑制剤となり得る可能性を示すことができた。
日本学術振興会, 若手研究, 北海道大学, Principal investigator, 22K14947

Development of Morganella phage cocktails for inhibition of histamine food poisoning in fishery products
2019年度学術研究助成
Jan. 2020 - Dec. 2021
Shogo Yamaki
Mayekawa Houonkai Foundation, 北海道大学大学院水産科学研究院, Principal investigator

The study on control of histamine poisoning of fishery products with peracetic acid　　　　　　　　　　　　　　　
平成31年度学術研究助成
Apr. 2019 - Mar. 2020
Shogo Yamaki, Yuji Kawai, Koji Yamazaki
The South Hokkaido Science Promotion Foundation, 北海道大学大学院水産科学研究院, Principal investigator

Broad-host-range bacteriophage EscoHU1 infecting Enterohemorrhagic Escherichia coli: characterization, infection mechanism, and application for food safety
Grants-in-Aid for Scientific Research Grant-in-Aid for Research Activity start-up
Aug. 2018 - Mar. 2020
Shogo Yamaki
In this study, broad-host-range bacteriophage EscoHU1 was characterized and investigated as an antimicrobial agent for the control of foodborne pathogens such as Escherichia coli and Salmonella enterica. EscoHU1 has head and tail structures, and this phage belongs to family Siphoviridae that has a long and flexible tail. In challenge tests using beef and milk, EscoHU1 reduced viable cell counts of E. coli, but did not reduce that of S. Typhimurium. The results from this study suggest that EscoHU1 has potential as the antimicrobial agent for the control of E. coli in contaminated food.
Japan Society for the Promotion of Science, Grant-in-Aid for Research Activity start-up, Hokkaido University, Principal investigator, 19K21155

ファージセラピーによるヒスタミン食中毒制御法の構築に関する研究
Grants-in-Aid for Scientific Research Grant-in-Aid for JSPS Fellows
Apr. 2016 - Mar. 2018
Shogo Yamaki
ヒスタミン食中毒は, ヒスタミンを過剰に蓄積した食品を喫食することにより発生しアレルギー様症状を呈する。食品へのヒスタミンの蓄積はヒスタミン生成菌の働きによって起こるため, 本食中毒の防止にはヒスタミン生成菌の制御方法の確立が必要であると考えられる。そこで本研究では, ヒスタミン食中毒の原因となるヒスタミン生成菌の制御法としてバクテリオファージの利用に着目し, バクテリオファージを用いたヒスタミン生成菌制御の方法について研究した。
平成29年度は, 過去に分離したMorganella morganiiに感染するバクテリオファージの混合物を用い, 耐性菌の出現抑制と食品でのヒスタミン生成菌ならびにヒスタミン蓄積抑制効果について研究を行った。バクテリオファージ混合物の耐性菌出現抑制効果については液体培地の系で実験を行った。バクテリオファージ混合物で宿主細菌を殺菌した結果, 混合物を構成する各バクテリオファージを単独で処理した場合と比較して耐性菌の出現率が有意に減少した。
次に, 食品におけるバクテリオファージ混合物の殺菌効果について検証した。ツナフレークにMorganella morganiiを接種しバクテリオファージ混合物を処理した結果, ツナフレーク保存中の生菌数とヒスタミン蓄積量がバクテリオファージ混合物未処理区と比較して大きく減少した。また, 同様の実験を生のマグロ魚肉を用いて行ったところ, ツナフレークでの実験よりも抑制効果は減少したが, バクテリオファージ混合物は魚肉中のMorganella morganiiの発育とヒスタミン蓄積を大きく抑制した。
以上, 平成29年度はMorganella morganiiのバクテリオファージ耐性菌の出現抑制に対する知見を得ることに成功し, バクテリオファージ混合物を用いた処理による魚肉のヒスタミン蓄積抑制効果を示した。
Japan Society for the Promotion of Science, Grant-in-Aid for JSPS Fellows, Hokkaido University, Principal investigator, 16J03433