Functional characterization of novel carotenoids-protein complex with aqueous properties found in vegetables and fruits

2023 Fiscal Year Final Research Report

• Project/Area Number: 19K02383
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 08030:Family and consumer sciences, and culture and living-related
• Research Institution: Kobe Women's University
• Principal Investigator: ANDO Seiichi 神戸女子大学, 家政学部, 教授 (80131986)
• Project Period (FY): 2019-04-01 – 2024-03-31
• Keywords: カロテノイド / 特異的タンパク質 / 水溶性 / 電気泳動 / 果実類 / 野菜類

Outline of Final Research Achievements

Some carotenoids, which are fat-soluble by nature, were found to be soluble in water in the pulp of satsuma mandarin, muskmelon, persimmon, loquat, carrot, and bell pepper. The pulp of the yellowish and reddish bell pepper cultivars was homogenized in 4 vol. of 12mM phosphate buffer (pH7.4) containing 137mM sodium chloride and centrifuged at 20,000xg for 30 min. at 5℃ to obtain the supernatant containing carotenoids. The supernatant was subjected to ammonium sulfate precipitation at 90% saturation and PD-10 desalting column to isolate a colored soluble fraction in 0.1% SDS solution. The colored soluble fraction was concentrated using a Vivaspin Turbo15 with MWCO of 10,000 daltons by centrifuging at 4,000xg for 60 min at 5℃ and subjected to SDS-PAGE, which revealed a colored band around molecular mass of 10,000 daltons in the unstained state. Some fat-soluble carotenoids in the pulp of bell pepper cultivars were thus associated with a specific protein to form a water-soluble complex.

Free Research Field

食品科学

Academic Significance and Societal Importance of the Research Achievements

本研究は、本来脂溶性であるカロテノイドの一部が、野菜や果実類では特異的タンパク質との相互作用によって水溶性に可溶化される実体を食品化学的に明らかにしたものであり、カロテノイドは脂溶性色素であるという従来の固定概念とは異なる、新たな学術的成果を提示することができた。
今後、脂溶性カロテノイドを水溶性に可溶化する特異的タンパク質の構造や機能の詳細な解析を通じて、野菜や果実類における水溶性化されるカロテノイドの機能性を食品生化学的に明らかにすること、さらに本特異的タンパク質には機能性食品素材としての新たな可能性を期待させる。