The Utilization of Indoleacetic Acid to Enhance the Tolerance of Microalgae to Antibiotics, Removal Capability, and Lipid Production

The utilization of microalgae for bioremediation presents a highly promising and cost-effective approach, offering advantages of simultaneous pollutant removal and biomass recovery. However, pollutants may adversely affect microalgal growth, potentially compromising both pollutant removal efficiency and biomass yield. In this study, the plant hormone indoleacetic acid was employed to enhance the tolerance to pollutants and lipid production capability of Chlorella vulgaris (C. vulgaris). Compared to the non-treated group, the addition of indoleacetic acid resulted in increased biomass, pigment content, sedimentation performance, lipid productivity and content, as well as antibiotic removal capacity in C. vulgaris. Furthermore, the effects of indoleacetic acid on C. vulgaris growth were elucidated through changes in antioxidant enzymes and fatty acid saturation. Overall, this study reveals the potential of plant hormones in enhancing microalgal tolerance and lipid productivity, providing a theoretical basis for the effective utilization of microalgae in achieving simultaneous pollutant removal and biofuel production.