Mechanism of establishment of pungent taste components in wasabi, native to Japan

2021 Fiscal Year Final Research Report

• Project/Area Number: 18K05616
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 39030:Horticultural science-related
• Research Institution: Gifu University
• Principal Investigator: Yamane Kyoko 岐阜大学, 応用生物科学部, 准教授 (00405359)
• Co-Investigator(Kenkyū-buntansha): 矢野 健太郎 明治大学, 農学部, 専任教授 (00446543)
• Project Period (FY): 2018-04-01 – 2022-03-31
• Keywords: ワサビ / 辛味成分 / グルコシノレート / UPLC / 栽培化 / 香辛料 / 進化 / 遺伝資源

Outline of Final Research Achievements

In this study, we aimed to elucidate "Why is wasabi spicy? Based on the previous report that wild relatives in Chiba which have no spicy condiment, we conducted a comparative analysis for Japanese Eutrema species using abundant genetic resources in Japan to understand the evolutionary background that led to this difference. As a result, we found that there is a great diversity of glucosinolate products in Japanese wasabi and its relatives. The differences among components by growing environment, site, season, and species indicate that wasabi may have evolved a mechanism to accumulate sinigrin (a precursor substance of pungency) and long-chain glucosinolates in the rhizome when adapting to the heavy snowfall on the Sea of Japan coast. The pungency of wasabi may have been a response substance to stresses unique to high snowfall areas.

Free Research Field

植物遺伝資源学

Academic Significance and Societal Importance of the Research Achievements

ワサビは日本固有種であり、日本で栽培化された数少ない経済植物として重要である。にもかかわらず、ワサビの特徴的な辛味が成立した進化的背景や遺伝基盤情報は不明な点が多かった。ワサビの辛味がどのようにして日本で成立し、栽培化に至ったのかを明らかにすることは、ワサビ生産に有用な基盤情報となりえるだけでなく、日本列島の自然環境を理解し、持続的に植物資源を利用し、保全するためにも重要である。本研究によりワサビの辛味成分が環境適応形質である可能性が示されたことは、遺伝進化学的や農学研究にとどまらず民族植物学や食文化など高い波及効果が見込める。