How is the nitrite contributing to our general and oral health promotion produced in oral microflora?

2020 Fiscal Year Final Research Report

• Project/Area Number: 17K12003
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Social dentistry
• Research Institution: Tohoku University
• Principal Investigator: WASHIO JUMPEI 東北大学, 歯学研究科, 講師 (20400260)
• Co-Investigator(Kenkyū-buntansha): 高橋 信博 東北大学, 歯学研究科, 教授 (60183852) ; 佐藤 拓一 新潟大学, 医歯学系, 教授 (10303132) ; 石黒 和子 東北大学, 歯学研究科, 大学院非常勤講師 (00755829)
• Project Period (FY): 2017-04-01 – 2021-03-31
• Keywords: 口腔細菌 / 代謝 / 亜硝酸

Outline of Final Research Achievements

In recent years, it attracts attention that oral bacteria can metabolize nitrate included in yellow-green vegetables or saliva to nitrite, that has antibacterial activity and vasodilatation effect, and which may contribute to maintain our general and oral health.However, the details about the production of nitrite in the oral cavity is still unknown. Therefore, we tried to clarify the whole aspect of nitrite production in the oral cavity.
The nitrite-producing activity in the oral cavity was higher in dental plaque than tongue coatings. The interindividual differences was also higher. It was clarified that the bacterial species such as Actinomyces, Shaalia, and　Veillonella species known as commensal bacteria mainly contribute to the nitrite production in oral cavity. In addition, it was also clarified that those nitrite-producing activity can be fluctuated by the various environmental factors such as an oxygen concentration, pH and the lactate concentration.

Free Research Field

口腔生化学／予防歯科学

Academic Significance and Societal Importance of the Research Achievements

亜硝酸塩は、その抗菌作用による口腔疾患の予防効果と、全身の血液拡張効果を通した循環器疾患予防効果に注目が集まっており、「口腔内細菌の代謝活動が口腔・全身の“健康”と関わる」という視点でのさらなる研究展開が期待される。また、本研究の知見からは、口腔細菌による亜硝酸塩産生が主に常在菌によって行われ、さらに環境によりその産生活性が調節されうることが明らかとなったことから、それらを利用し、口腔・全身疾患の予防効果を高める方法の開発に寄与する可能性が考えられた。