Effects of salt consumption by the scent of food and spice

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K05945
• 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: Nihon University
• Principal Investigator: OSADA Kazumi 日本大学, 生物資源科学部, 教授 (00382490)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 嗅覚生理学 / 動物行動 / 嗅覚生理学

Outline of Final Research Achievements

We developed a system controlling gaseous concentration by the SPME system, then conducted the preference test by two-bottle choice apparatus to know the preference between NaCl solution and the pure water to C57BL/6j presence and absence of food odor. We found out the dose-dependence effect of oregano (carvacrol) odors on reducing salt intake. The preference for the saline was declined by the oregano odor in both sexes but not in males by the carvacrol.
The anosmia mice with ZnSO4 injection were still sensitive to the oregano odor, suggesting that there may be another mechanism from the olfactory system to transfer the information reducing salt appetite. We explored the effect of the oregano volatiles on some brain areas. As a result, both sexes were significantly stimulated on ventral parts of the bed nucleus stria terminalis (VST), which is the center of salt consumption, by oregano. Therefore, oregano stimulated VST inducing decreased salt appetite-stimulating.

Free Research Field

農芸化学

Academic Significance and Societal Importance of the Research Achievements

本研究の成果は，オレガノの匂い成分を嗅ぐことで，適塩効果が誘起することを明らかにした．活性成分（カルバクロール）も同定し，また適塩効果の大脳生理学的メカニズムの一部を解明した．塩分の過剰摂取は世界的な問題であり，安全で好ましい食品の匂い刺激のみで適塩効果を発揮することは食事に伴う塩分摂取過剰に対する自然な対処法となり，本成果の社会的・産業的意義は極めて大きい．嗅覚障害マウスでの適塩効果は嗅覚以外の適刺激を明らかにするうえで重要な発見と言える．食塩摂取を調節する分界条床核腹側部をオレガノの匂いが刺激する今回の結果は，中枢レベルでの適塩メカニズムに新たな知見を提供し，その学術的意義は極めて高い．