Possibility creation of new vitamin-like component derived from the elucidation of absorption metabolism of rice characteristic component g-oryzanol

2018 Fiscal Year Final Research Report

• Project/Area Number: 17K19217
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Research Field: Agricultural chemistry and related fields
• Research Institution: Tohoku University
• Principal Investigator: Nakagawa Kiyotaka 東北大学, 農学研究科, 教授 (80361145)
• Co-Investigator(Kenkyū-buntansha): 宮澤 陽夫 東北大学, 農学研究科, 教授 (20157639)
• Project Period (FY): 2017-06-30 – 2019-03-31
• Keywords: γ-オリザノール / 吸収代謝 / ビタミン様活性

Outline of Final Research Achievements

We aimed to explore the potential vitamin-like activities of γ-oryzanol via elucidation of the mechanisms by which γ-oryzanol is absorbed and metabolized. Analytical methods (i.e., extraction, purification, and LC-MS/MS methods) to analyze γ-oryzanol from in vivo samples such as plasma and organs were developed. With the use of such methods, we analyzed the blood and organs of mice following a long-term feeding of γ-oryzanol and found the possibility that a part of γ-oryzanol accumulates in vivo to demonstrate bioactivity. Additionally, we demonstrated that γ-oryzanol is absorbed from the intestine and that a part of γ-oryzanol is metabolized after intestinal absorption. We also revealed that γ-oryzanol molecular species that were previously considered to be characteristic to rice were also contained in barley. These features may potentially enable considering γ-oryzanol as a vitamin-like compound.

Free Research Field

食品機能学

Academic Significance and Societal Importance of the Research Achievements

特定保健用食品をはじめとする機能性食品などの開発では、その食品成分の消化吸収代謝を理解することは非常に重要と考えられる。本研究成果は生体におけるγ-オリザノールの吸収代謝機構の一端を明らかにした。さらには、γ-オリザノール生体や食品において常時存在することを示唆しており、γ-オリザノールがビタミン様活性を有する可能性を後押しする結果を得た。本研究によって健康増進にむけたγ-オリザノールのさらなる活用が期待されることから、その社会的波及性は大きい。