Elucidation of the mechanism of coloration induced by cooking of the ancient pea "Tutankhamun pea" and evaluation of its antioxidant properties

2022 Fiscal Year Final Research Report

• Project/Area Number: 17K00838
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Eating habits
• Research Institution: Tokushima Bunri University
• Principal Investigator: Kondo Miki 徳島文理大学, 人間生活学部, 准教授 (80326412)
• Project Period (FY): 2017-04-01 – 2023-03-31
• Keywords: ツタンカーメンエンドウ / 着色反応 / 抗酸化活性 / エピガロカテキンの二量体 / 調理 / 莢

Outline of Final Research Achievements

The immature Tutankhamun pea (Pisum sativum L.) have the unique characteristic of changing from green to reddish brown upon heating and are known to have　higher antioxidant activity than normal varieties. In this study, the coloring mechanism was elucidated and antioxidant components in the pea were identified. It was suggested that the precursor of the coloring component produced by　heating is a dimer of (-)-epigallocatechin, and the coloring component is a　dehydrogenated product of this dimer. Furthermore, the dimer of (-)　epigallocatechin, the precursor of the colored component, was identified as the major antioxidant compound. These results demonstrated that (-)-epigallocatechin dimers are responsible for the unique characteristics of Tutankhamun peas. In addition, four anthocyanins were identified as antioxidant components of the capsules, and their antioxidant properties of the capsules were demonstrated in a mouse model of oxidative stress.

Free Research Field

調理科学、食品化学

Academic Significance and Societal Importance of the Research Achievements

これまで現象のみが捉えられていたツタンカーメンエンドウの加熱中に生じる着色反応のメカニズムを提示した。着色や抗酸化活性には共通して(-)-エピガロカテキンの二量体が関与しており、当該成分が当該エンドウのユニークな特徴を与えていることが明らかになった。また、食生活において抗酸化活性を効果的に活用するためには水溶性の抗酸化成分の損失を避ける調理方法が重要であり、加工食品の製造にも応用可能な情報を提供した。さらに、約5割の廃棄部に相当する莢に含まれる抗酸化成分の同定とその生体抗酸化性の立証は、未利用資源である莢を機能性食品素材等として活用する上で科学的基盤として役立つものと考えられる。