Developpement of unit operation with data accumulation of algal straines for future algal industries

2015 Fiscal Year Final Research Report

• Project/Area Number: 25709085
• Research Category: Grant-in-Aid for Young Scientists (A)
• Allocation Type: Partial Multi-year Fund
• Research Field: Earth system and resources engineering
• Research Institution: Tohoku University
• Principal Investigator: OTA MASAKI 東北大学, 工学(系)研究科(研究院), 助教 (50455804)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 藻類 / バイオマス / 抽出 / 超臨界流体 / 分離 / 光合成 / 油脂

Outline of Final Research Achievements

Photoautotrophic fatty acid production of a highly CO2-tolerant green alga Chlorococcum littorale in the presence of inorganic carbon at 295 K and light intensity of 170 mmolphoton m-2 s-1 was investigated. CO2 concentration in the bubbling gas was adjusted by mixingpure gas components of CO2 and N2 to avoid photorespiration and b-oxidation of fatty acids under O2 surrounding conditions. Maximum content of total fatty acid showed pHdependence
after nitrate depletion of the culture media and increased with the corresponding inorganic carbon ratio. Namely, [HCO32]/([CO2]1n[CO223]) ratio in the culture media was found to be a controlling factor for photoautotrophic fatty acid production after the nitrate limitation. At a CO2 concentration of 5% (vol/vol) and a pH of 6.7, the fatty acid content was 47.8 wt % (dry basis) at its maximum that is comparable with land plant seed oils. On the other hand, simple extraction methods were also developped in this work.

Free Research Field

化学工学