NPK-10:26:26 complex fertilizer assisted optimal cultivation of Dunaliella tertiolecta using response surface methodology and genetic algorithm

A culture medium based on NPK-10:26:26 fertilizer was formulated for enhanced biomass and lipid production of Dunaliella tertiolecta by selecting appropriate nutrients and environmental parameters. Five-level-five-factor central composite design assisted response surface methodology was adopted for optimal cultivation of D. tertiolecta and results were compared with simple genetic algorithm (GA). Significant improvement in biomass and lipid production was obtained using newly formulated fertilizer medium over f/2 medium. Following optimal parameters [i.e., NaHCO3, (mM), NPK-10:26:26 (g L−1), NaCl (M), light intensity (μmol m−2 s−1) and temperature (°C)] were obtained for maximum biomass (1.98 g L−1) and lipid production (0.76 g L−1): (42.50, 0.33, 1.09, 125, 25.13) and (38.44, 0.40, 1.25, 125, 24.5), respectively using GA. A multi-objective optimization was solved using non-dominated sorting GA to find best operating variables to maximize biomass and lipid production simultaneously. Effects of operating parameters and their interactions on algae and lipid productivity were successfully revealed.