New insight into structural analsis on plant food proteins by small-angle X-ray and neutron scattering

2020 Fiscal Year Final Research Report

• Project/Area Number: 17K07816
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Food science
• Research Institution: Kyoto University
• Principal Investigator: Sato Nobuhiro 京都大学, 複合原子力科学研究所, 助教 (10303918)
• Project Period (FY): 2017-04-01 – 2021-03-31
• Keywords: X線小角散乱 / 中性子小角散乱 / 食品構造 / 食品物性 / 小麦タンパク質 / 大豆タンパク質

Outline of Final Research Achievements

Nanostructure of plant food protein assemblies were investigated by small-angle X-ray and neutron scattering. For wheat protein gliadin hydrates, it was found that the addition of sodium chloride induces hierarchical inhomogeneous structure with different sizes. It was also found that the deamidation of gliadin greatly influences the effect of sodium chloride on the aggregate structure. Furthermore, it was demonstrated that the addition of salts other than sodium chloride significantly changes the physical properties of the gliadin aggregates, even though there was no significant difference in the nanostructure revealed by SAXS. For soybean protein, it was found that the presence of buffer solutions and increase in ionic strength raise the temperature at which thermal denaturation occurs, leading to improved thermal stability of associated structure of soy proteins.

Free Research Field

食品構造学、ナノ生体構造学

Academic Significance and Societal Importance of the Research Achievements

凝集状態の食品タンパク質についてこれまで未解明だった、内部構造、すなわち構成タンパク質の存在状態や凝集体内での構造の揺らぎ、他の構成成分との相関構造についてSAXSやSANSを用いて解析する一方、物性や構造の変化をもたらす種々の条件（脱アミド化や異なる種類の添加塩、イオン強度等）を明らかにすることによって、高品質の食品や高機能の食品素材を製造するための知見を提供するとともに、ナノメートルからマイクロメートルの領域における食品タンパク質の階層構造を統一的に理解し、食品構造化学の新しい展開をもたらすことができた。