Microbial lipids accumulation to provide alternative oil resource is an exciting research area, obtaining increasing attention recently for the biodiesel production due to its high production efficiency and less demand of agricultural land. This study was carried out to evaluate the potential of glucose and sucrose concentrations as carbon sources for culturing Chlorella kessleri with higher oil production in heterotrophic and mixotrophic cultures. Experiments were performed by incubating algal cultures with (0.5, 2, 4, 6, and 8%) glucose and sucrose for an incubation period of 21 days under mixotrophic and heterotrophic conditions. It was found that glucose and sucrose exerted significant promotion on growth of C. kessleri under both conditions. The maximum lipid production was 5.1 g/L at 0.5% glucose under mixotrophic conditions. Gas chromatography mass spectrometry (GC-MS) analysis showed that change in the nature of supplemented organic carbon sources, mixotrophic C. kessleri cells displayed different percentages of both fatty acids. Results in this study suggest that C. kessleri could provide high lipids productivity combined with high fatty acid content and biomass in mixotrophic culture than hetero and autotrophic growth, which is a promise to be one of the sources of biodiesel.
Key words: Chlorella kessleri, mixotrophic, heterotrophic cultivation, Biomass production, lipid and fatty acid accumulation
|
