Mixotrophic cultivation of oleaginous Chlorella sp. KR-1 mediated by actual coal-fired flue gas for biodiesel production.
Flue gases mainly consist of CO2 that can be utilized to facilitate microalgal culture for bioenergy production. In the present study, to evaluate the feasibility of the utilization of flue gas from a coal-burning power plant, an indigenous and high-CO2-tolerant oleaginous microalga, Chlorella sp. KR-1, was cultivated under mixotrophic conditions, and the results were evaluated. When the culture was mediated by flue gas, highest biomass (0.8 g cells/L·d) and FAME (fatty acid methyl esters) productivity (121 mg/L·d) were achieved in the mixotrophic mode with 5 g/L glucose, 5 mM nitrate, and a flow rate of 0.2 vvm. By contrast, the photoautotrophic cultivation resulted in a lower biomass (0.45 g cells/L·d) and a lower FAME productivity (60.2 mg/L·d). In general, the fatty acid profiles of Chlorella sp. KR-1 revealed meaningful contents (>40 % of saturated and mono-unsaturated fatty acids) under the mixotrophic condition, which enables the obtainment of a better quality of biodiesel than is possible under the autotrophic condition. Conclusively then, it was established that a microalgal culture mediated by flue gas can be improved by adoption of mixotrophic cultivation systems.
Biomass and Waste Energy Laboratory, Korea Institute of Energy Research (KIER), Daejeon, 305-343, Republic of Korea.
Ramasamy
R
Praveenkumar
Bohwa
B
Kim
Eunji
E
Choi
Kyubock
K
Lee
Sunja
S
Cho
Ju-Soo
JS
Hyun
Ji-Yeon
JY
Park
Young-Chul
YC
Lee
Hyun Uk
HU
Lee
Jin-Suk
JS
Lee
You-Kwan
YK
Oh
D056804:Biofuels; D019149:Bioreactors; D002708:Chlorella / Q000254:growth & development / Q000378:metabolism*; D003031:Coal; D005740:Gases
D056804:Biofuels; D003031:Coal; D005740:Gases