Bioenergy application of Dunaliella salina SA 134 grown at various salinity levels for lipid production.

The biofuels are receiving considerable attention as a substitute for petro diesel. For microalgae, the cell density or biomass and lipid contents are key components for biodiesel production. This study was conducted to develop favorable culture conditions for Dunaliella salina to maximize its biomass and lipid accumulation. The effect of salinity (0.5 to 2.5 M NaCl) on the cell population, biochemical composition, and lipid output of Dunaliella salina was examined under a controlled environment for 21 days. Maximum growth (6.57 × 10(7) to 7.17 × 10(7)cells mL(-1)) potentials were observed at 1.5 to 2 M NaCl. The photosynthetic pigments and carbohydrates also showed trends similar to growth. The maximum carotenoid level (5.16 mg L(-1)) was recorded at 2 M NaCl. Almost all physicochemical parameters increased with increases in salinity, biomass (1231.66 ± 1.26 mg L(-1)) and lipid content (248.33 mg L(-1)), as recorded at 2 M NaCl. Based on fluorescence intensity, the highest values (11.84 × 10(7)cells/ml) of neutral lipids and total lipids (22.28%) were recorded at optimum salinity levels. The present study suggests that a high biomass and lipid accumulation of Dunaliella salina SA 134 could be obtained at the 2 M NaCl level.