Microorganisms and enzymes implicated in degradation of tetrodotoxin, pufferfish toxin

2015 Fiscal Year Final Research Report

• Project/Area Number: 26660169
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Aquatic life science
• Research Institution: Tokyo University of Marine Science and Technology
• Principal Investigator: Nagashima Yuji 東京海洋大学, その他部局等, 教授 (40180484)
• Co-Investigator(Kenkyū-buntansha): NAGAI MAKOTO 岐阜医療科学大学, 保健科学科, 准教授 (30460497)
• Co-Investigator(Renkei-kenkyūsha): KOBAYASHI TAKESHI 東京海洋大学, 学術研究院, 准教授 (60242327)
• Research Collaborator: KIRIAKE AYA 東京海洋大学, 海洋科学部, 博士研究員 ; OHTA AKIRA 東京海洋大学, 大学院海洋科学技術研究科, 博士前期課程 ; OKAYAMA SAKURAKO 東京海洋大学, 大学院海洋科学技術研究科, 博士前期課程
• Project Period (FY): 2014-04-01 – 2016-03-31
• Keywords: 水産学 / 生体分子 / フグ毒 / 糠漬け / メタゲノム解析

Outline of Final Research Achievements

Tetrodotoxin (TTX) is thought to originate in marine bacteria and widely distributes in aquatic environments. However, there has been no information about degradation of TTX in nature. Therefore, we explored microorganisms involved in degradation of TTX to clarify the toxin-degradation mechanism, focusing on pufferfish ovary fermented with rice bran, Japanese traditional fermented food. It is known by experience that the fermentation of pufferfish ovary remarkably decrease toxicity during process over 2 years. However, the present study demonstrated that TTX was just transferred from ovary to surrounding by salting and fermentation process, suggesting no or less implication of microorganisms in decreasing toxicity. Metagenomic analysis revealed that extremophiles were detected in salt and rice bran during preservation and the microorganisms managed degradation and/or depression of organic substances in fermented pufferfish ovary by interference.

Free Research Field

水産化学