Elucidation of the in vivo absorption and metabolism of g-oryzanol (OZ) and the biosynthetic pathway of OZ in plants

2020 Fiscal Year Final Research Report

• Project/Area Number: 19K15783
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 38050:Food sciences-related
• Research Institution: Tohoku University
• Principal Investigator: Junya Ito 東北大学, 農学研究科, 助教 (50781647)
• Project Period (FY): 2019-04-01 – 2021-03-31
• Keywords: γ-オリザノール / 吸収代謝 / 生合成 / LC-MS/MS

Outline of Final Research Achievements

To elucidate the in vivo absorption and metabolism of γ-oryzanol (OZ) and the biosynthetic pathway of OZ in plants, we conducted (1) elucidation of the absorption and metabolism of OZ in vivo aiming at clarifying the active form/metabolite of OZ, (2)-(1) structural determination and evaluation of the distribution of triterpene alcohol (TTA)-type OZ molecular species in barley, and (2)-(2) elucidation of the biosynthetic pathway of OZ in rice and barley. From (1), we identified that the absorption and metabolism of OZ differ among OZ molecular species, hence different OZ molecular species existed in vivo in different forms. In (2)-(1), we revealed that TTA-type OZ, previously considered to exist only in rice, also existed in various barley varieties. In (2)-(2), we demonstrated the existence of OZ-like compounds that possess caffeic acid as a backbone, which were useful to estimate the biosynthetic pathway of OZ.

Free Research Field

食品機能学

Academic Significance and Societal Importance of the Research Achievements

本研究には、質量分析をはじめとした高度な分析技術によるOZやOZの代謝物・前駆体の詳細な解析が必須であり、申請者はこれまでにこのような解析手法の構築や活用に重点的に取り組んできた。これらの独創的な研究によって、優れた機能性を有するOZの吸収代謝や活性本体、作用機序の理解を真に深めるとともに、世界的にも不明な米や大麦等における生合成経路の解明を目指す。これらの成果は、OZを通じた健康実現の基盤創造へ繋がり、その社会的意義と波及性は極めて大きい。