Pristine carbon dots boost the growth of Chlorella vulgaris by enhancing photosynthesis

Microalgae has been identified as a promising source for biofuels production due to its superior characteristics. Carbon dots (CDs) with low toxicity and appreciable biocompatibility have been widely applied in bioapplication. In this work, Chlorella vulgaris is adopted as a model microalgae to study the impacts of CDs on it. The CDs are low toxicity and biodegradable and they can increase the biomass and growth rate by 17 and 21%, respectively. That is due to the CDs could be degraded by Chlorella vulgaris and producing numerous CO2, which could be immobilized by chloroplast and enhanced photosynthesis. And the CDs can improve the activity of Rubisco in vivo by 34%. Furthermore, these CDs as an antioxidant can protect Chlorella vulgaris cells against the damage of UV radiation and enhance the specific growth rate and the biomass by 17 and 18% under UV radiation.