Lipid production by Chlorella vulgaris after a shift from nutrient-rich to nitrogen starvation conditions

► A two-staged process was used to produce lipids from Chlorella vulgaris. ► The 1st stage is for a fast and high density cell growth under nutrient-rich conditions. ► The 2nd stage is for lipid production under limitations of nitrate and controlled conditions. ► About 53% of dry cell weight accumulated as lipids after 24 h at an optimal 2nd stage conditions.