Media composition, light intensity and photoperiod significantly affect the algal growth and productivity and their optimization is important for the commercialization of microalgae based biofuels. In the present study, effects of different culture medium, light intensity and photoperiod were studied on growth, biomass productivity, and biochemical composition of a fresh water microalgae Ankistrodesmus falcatus in batch culture. The results revealed that A. falcatus could yield more than 35% of total lipid (containing around 65.74% neutral lipid) along with optimal growth (0.20 mu) and biomass productivity (7.9 mg/L/day) in the BG-11 medium under a light intensity of 60 mu mol m(-2) s(-1) and 12:12 (Light: Dark) cycle. The highest total lipid yield of 67.2% (containing 72.68% of neutral lipid) was observed in Zarrouk's medium grown culture but with altered cell morphology and ultra-structural changes. (C) 2014 Elsevier Ltd. All rights reserved.