Enhanced microalgal growth and lipid accumulation by addition of different nanoparticles under xenon lamp illumination

In this study, the growth and lipid accumulation of Scenedesmus sp. using different nanoparticles and light sources were investigated. Xenon lamp can produce a broad illumination spectrum, and exhibited better performance than light-emitting diode. SiC and g-C₃N₄ nanoparticles improved the biomass and lipid accumulation, whereas TiO₂ and TiC nanoparticles had inhibitory influence on microalgae. Lipid production can be improved by oxidative stress produced by combination of nanoparticles and xenon lamp irradiation. At the optimal SiC nanoparticles concentration of 150 mg L⁻¹ and photoperiod of 6:18 h, the maximum biomass concentration and total lipid content reached 3.18 g L⁻¹ and 40.26%, respectively. The addition of SiC nanoparticles could promote the substrate utilization rate and induce stress condition, thereby enhancing the activity of acetyl-CoA carboxylase and lipid biosynthesis. This research shows that SiC nanoparticles addition combined with xenon lamp illumination is a promising strategy to promote microalgal growth and lipid accumulation.