Augmentation and starvation of calcium, magnesium, phosphate on lipid production of Scenedesmus obliquus

Theoretical evaluation of algal biodiesel shows extravagance and economical impedance. Lipid productivity has been a prominent strategy to attain economic viability. The present study investigates the effect of starvation and supplementation of Ca, Mg and P on growth and lipid accumulation in microalga Scenedesmus obliquus. Calcium and phosphate starvation induced lipid accumulation by 52.9% and 47.6% of DCW (dry cell weight) respectively; supplementation with 300 mgL-1 of magnesium induced lipid accumulation by 54.6% DCW. Interestingly growth was not affected at 300 mg/L of magnesium and conditions like calcium and phosphate starvation affected the growth but not completely retarded. The statistical studies with Box-Behnken model revealed that the macronutrients exerted their significant impact on growth and lipid accumulation individually than interactively. •Surplus nutrients supply influence lipid accumulation.•Ca and Mg significantly affect the growth and lipid of Scenedesmus obliquus.•High lipid accumulation of 54.6% obtained in surplus Mg.•P starvation induced lipid accumulation up to 52.9%.•Multiple nutrient stresses adversely affect the lipid productivity.