Optimization of light for growth, photosynthesis, and hydrocarbon production by the colonial microalga Botryococcus braunii BOT-22

► Hydrocarbon production by B. braunii saturated at 200 μmol photons m−2 s−1. ► Hydrocarbons stored in the colony were not used as substrate for respiration. ► Neutral lipid body in the cell was degraded by consumption in the dark.