Effect of High Concentrations of CO 2 on the Cell Density, Lipid Content and Fatty Acid Components of Nannochloropsis oceanica

In order to evaluate the capability of Nannochloropsis oceanica to product biodiesel, the cell density, lipid content and fatty acid components of N. oceanica under different CO 2 concentrations were analized. The results indicated that the cell density and lipid content of N. oceanica were increased under 5% CO 2 , but the growth of N. oceanica was inhibited under 10% and 15% CO 2 . Over 88% of the N. oceanica lipids produced consisted of C16 ~ C18 fatty acids and the concentration of unsaturated fatty acids (>69%) is high and suitable for biofuel production. The highest content of eicosapentaenoic acid (EPA) was also obtained under 5% CO 2 . The present results suggested that N. oceanica was suitable biodiesel feedstock and the maximum economic effectiveness will be obtained using flue gas containing 5% CO 2 in the cultivation of N. oceanica .