(602ap) Induction of Microalgal Lipids for Biodiesel Production

The production of biofuels such as biodiesel from biomass has gained accelerated interest in recent years as these fuels are becoming increasingly economically-viable, renewable, and carbon-neutral energy sources.  One reason for this renewed interest derives from new policy and legislation such as sustainable biofuel targets in the US Energy Policy Act (EPA 2005) and Energy Independence and Security Act (EISA 2007). There have been many attempts in deriving biodiesel fuel from different bioenergy crops such as corn, canola, soybeans, palm, sugar cane and vegetable oil. However there are some significant challenges, these includes: depleting feedstock supplies, land use change impacts, food use competition resulting in high prices and inability to completely displace fossil fuel.

In this study, Chlorella Vulgaris microalgae was cultivated under different stressful conditions to produce high-yield biomass with high lipid content which were converted to biodiesel fuel by transesterification.  These stressful conditions include the use of high CO₂ concentration, high (25-40 W/m²) and low (0-10 W/m²) light intensity. Different operating constraints were investigated to optimize the lipid induction process in Chlorella Vulgaris.  The approach used in this study was to culture the Chlorella Vulgaris microalgae with inoculation 1x10⁵ cells/ml in a 250-ml Erlenmeyer flask, irradiated with fluorescence light bulbs and cultured at room temperature of 25^oC. Using these conditions we were able to determine which were suitable for cultivating the algae.  During the experiment, Nile red dye was used as a hydrophobic fluorescent probe to detect the intracellular lipid deposits in the cell concentrations.