Isolation of noble anammox bacteria possessing high tolerance of oxygen and light to develop soil remediation technology

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K18887
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 22:Civil engineering and related fields
• Research Institution: Kumamoto University
• Principal Investigator: Kawagoshi Yasunori 熊本大学, くまもと水循環・減災研究教育センター, 教授 (00291211)
• Co-Investigator(Kenkyū-buntansha): 伊藤 紘晃 熊本大学, くまもと水循環・減災研究教育センター, 助教 (80637182) ; 濱 武英 熊本大学, くまもと水循環・減災研究教育センター, 准教授 (30512008)
• Project Period (FY): 2018-06-29 – 2021-03-31
• Keywords: Anammox / 酸素耐性 / 集積培養

Outline of Final Research Achievements

We succeeded in the establishment of enrichment culture of Anammox biomass which are highly tolerant to dissolved oxygen concentration (DO) from the sludge of two oxidation-ditch plants through batch and continuous experiments. The enriched anammox biomass showed well growth and high nitrogen removal performance in a continuous reactor supplied with the anammox medium including more than 6.0 mg/L DO. Two kinds of anammox bacteria of 'Candidatus Anammoxoglobus' and' Candidatus Brocadia' were detected in the reactors from the bacterial community analysis by next-generation sequencing technique.

Free Research Field

水環境工学

Academic Significance and Societal Importance of the Research Achievements

これまで，Anammox細菌は偏性嫌気性の細菌であり，酸素濃度の高い自然環境での利用は困難と認識されてきた。しかし，本研究によって，溶存酸素濃度の高い培地供給下においても増殖して窒素除去能を示すAnammox細菌の集積培養に成功したことから，酸素のAnammox細菌への影響について新たな知見を与える可能性が高い。また，本研究で得られた集積培養バイオマスは，部分亜硝酸化-Anammox法など酸素濃度の比較的高い条件への適用に高いアドバンテージを有し，さらに今後は，人工湿地や土壌・底質の浄化といった汚染現場・現地における環境修復への応用，展開が期待できる。