Initial population density plays a vital role to enhance biodiesel productivity of Tetraselmis sp. under reciprocal nitrogen concentration

This study reveal the combined effect of initial population density (IPD) (0.1, 0.5 and 1.0 g L−1) and nitrogen (0 N-nil nitrogen; 1 N-optimized concentration of nitrogen; 2 N-doubling of optimized nitrogen concentration) on growth, biomass, lipid and fatty acid content of the oceanic microalga Tetraselmis sp. were tested. The experiment was carried out in multi-room light-emitting diode chamber for two weeks with continuous illumination of light such as 14:10 h L:D of photoperiod (PP) and 150 μmol m−2 s−1 of photosynthetic photon flux intensity (PPFI). The maximum optical density (1.15 abs), cells concentration (253 × 104 cells mL−1), chlorophyll 'a' (2.68 mg L−1) and fatty acids content were found in the combination of 0.5 g L−1 initial population density and 1 N, whereas the highest biomass (0.95 g L−1) was noticed in 1 g L−1 initial population density and 2 N, and total lipid (48 ± 1.14%) was high in 0.5 g L−1 initial population density and 2 N combination.