Lipid production of Chlorella vulgaris from lipid-extracted microalgal biomass residues through two-step enzymatic hydrolysis

Lipid-extracted microalgal biomass residues (LMBRs) were treated using cellulase, neutrase and alcalase in a two-step process and the resulting hydrolysates were used as a source of nutrients for the cultivation of Chlorella vulgaris under non-aerated and aerated conditions for lipid production. Aeration was favorable for cell growth and lipid accumulation and a biomass of approximately 3.28 g L−1, lipid content of 35% and lipid productivity of 116 mg L−1 d−1 were obtained. Thus, the tested mode of LMBRs utilization was effective for nutrient recycling in microalgal biodiesel production.