Prebiotics effect of sphingolipids contained in fermented foods

• Project/Area Number: 20K05809
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 38020:Applied microbiology-related
• Research Institution: Saga University
• Principal Investigator: Kitagaki Hiroshi 佐賀大学, 農学部, 教授 (70372208)
• Co-Investigator(Kenkyū-buntansha): 中山 二郎 九州大学, 農学研究院, 教授 (40217930)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Project Status: Completed (Fiscal Year 2022)
• Budget Amount: ¥4,290,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥990,000); Fiscal Year 2022: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000); Fiscal Year 2021: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000); Fiscal Year 2020: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000)
• Keywords: スフィンゴ脂質 / 腸内細菌 / プレバイオティクス / グルコシルセラミド / 二次胆汁酸 / 麹 / グリコシルセラミド

Outline of Research at the Start

本研究では、麹グリコシルセラミドを加えると腸内細菌叢にどのような影響があるか、麹グリコシルセラミドのどの化学構造がこのような効果をもたらすかをNGSやRTPCRなどの最先端解析技術と独自開発した培養システムを使って明らかにする。これらの研究により、麹グリコシルセラミドのどの化学的構造がどの腸内細菌の増殖あるいは抑制に寄与するのかが明らかになることが期待される。

Outline of Final Research Achievements

Functionality of sphingolipids, especially glucosylceramide, which are contained in Japanese fermented foods, was investigated. It turned out that glucosylceramide works on gram-positive intestinal bacteria through NGS analysis. Especially, glucosylceramide altered the metabolism of Blautia coccoides. The mechanism was considered to be through the increase of tolerance to secondary bile acids. Specificity of glucosylceramide contained in fungi and fermented foods remained to be elucidated. From these studies, glucosylceramide was considered to pass through the small intestine and reach the large intestine, and protect intestinal gram positive bacteria from secondary bile acids. Since glucosylceramide is abundantly contained in fermented foods, this knowledge should be a new knowledge on the functionality of fermented foods. Furthermore, this is the first report that glucosylceramide functions on the intestinal microbes, it can be utilized as a new prebiotic substance.

Academic Significance and Societal Importance of the Research Achievements

スフィンゴ脂質、特にグルコシルセラミドの腸内細菌への影響を初めて明らかにし国際学術誌に論文発表した。発酵食品の新たな健康機能性になると考えられた。日本の発酵食品の健康機能性をアピールするための新たな根拠になると思われる。プレバイオティクスの新たなジャンルになると思われる。