Modification and application of food protein functionalities by utilizing oxidoreductases

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K05913
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 38050:Food sciences-related
• Research Institution: Tokyo University of Pharmacy and Life Science
• Principal Investigator: Kumazawa Yoshiyuki 東京薬科大学, 生命科学部, 教授 (90833054)
• Co-Investigator(Kenkyū-buntansha): 時下 進一 東京薬科大学, 生命科学部, 准教授 (60266898)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 酵素 / ラッカーゼ / チロシナーゼ / 架橋高分子化 / 食品物性 / 食品タンパク質

Outline of Final Research Achievements

Expression systems for laccases derived from psychrophile and thermophile in E. Coli, and tyrosinase derived from squid ink in yeast, Pichia pastoris, were constructed. Enzyme properties and utilization for protein modification were evaluated. Enzymes from psychrophile and squid ink showed relatively higher activity in low temperature than enzyme from thermophile. Protein polymerizations were observed by all enzymes in the presence of low molecular phenol compounds worked as mediators. Different formation of crosslinking was observed by different mediators. Di-tyrosines were detected in some of crosslinking products indicating crosslinking in between tyrosine and tyrosine. Egg white and milk protein were treated by laccase and prepared heat gel, acid gel and cheese curd. Results suggested that hardness of egg white gel, water retention and curd yield of milk protein were increased, whereas hardness of acid gel as yogurt was decreased.

Free Research Field

食品科学

Academic Significance and Societal Importance of the Research Achievements

加工食品の原料としての食品タンパク質には、ゲル形成性、乳化性、保水性、起泡性等様々な機能特性があり、食品の製造工程や製品品質に大きな影響を与える要因となっている。多様化する現代社会においては、食に求めるニーズもまた多様化しており、それに応えるために様々な原料素材や技術が研究開発されている。機能改質の手段の一つとして、酵素的改質技術が知られているが、上述した特性改質を可能とする酵素として、トランスグルタミナーゼ（TG）が挙げられる。本研究は、TGに加えた新たな機能改質技術の検討であり、多様化する食のニーズやおいしさの提供に資するものである。