Development of a high-rate biofuel production system using a newly isolated alga, Chlorococcum sp.

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K12276
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 64050:Sound material-cycle social systems-related
• Research Institution: Hiroshima National College of Maritime Technology
• Principal Investigator: Ohnuma Mio 広島商船高等専門学校, その他部局等, 准教授 (70594076)
• Co-Investigator(Kenkyū-buntansha): 三角 修己 山口大学, 大学院創成科学研究科, 教授 (90583625)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 微細藻類 / バイオ燃料 / 細胞培養 / 油脂生産 / 野外培養

Outline of Final Research Achievements

A field culture system was developed to obtain algal biofuel from the green alga Chlorococcum sp., which has high oil production and cell proliferation capacity. A culture medium developed in a previous study that allows high oil production and cell proliferation was used. Improved pre-culture methods for field culture have made maintaining cells at approximately twice their concentration possible before the improvements were made. We developed an open culture system (100 L) and a closed sea culture system (10 L) as field culture systems. Since Chlorococcum sp. has cell-sedimentation properties, sedimentation rates were measured. The result indicated that spontaneous sedimentation can be used for primary enrichment during cell harvest.

Free Research Field

植物細胞生物学

Academic Significance and Societal Importance of the Research Achievements

藻類バイオ燃料を社会実装化するには、低コスト野外培養系の構築が必須である。本研究で、Chlorococcum sp.は、油脂生産能・増殖能が高いだけでなく、細胞沈降性があることが明らかになった。一般に、微細藻類の細胞を収穫するときは、遠心分離や濾過などコストの高い方法が取られることが多いが、第一段階の濃縮を沈殿によって行うことにより、大幅なコストカットが可能と考えられる。本藻を用いて野外大型培養のさらなる改良を行うことは、藻類バイオ燃料の社会実装化に貢献すると考えられる。