Effects of sulfonamide on water remediation by aquatic plants: Insight from toxicological responses

Overuse of antibiotics such as sulfonamide (SA) has led to their excess existence in water environment, which would threaten water ecological security and human health. In this study, the resistance of three plants to SA was systematically studied. The relative growth rate (RGR) of Pistia stratiotes L. remained around 55 % without significant changes when the SA concentration increased from 0 to 30 mg/L, which in Canna indica L. and Eichhornia crassipes has significant decrease, showing the best resistance of Pistia stratiotes L. to SA stress This property will be beneficial for relieving SA toxicity in wastewater treatment. This study identified that aquatic plants promoted the removal of SA through the action of microorganisms rather than absorption and decomposition by the plant itself. Additionally, the presence of SA inhibited the growth of aquatic plants, which resulted in significant increases in peroxidase, catalase, superoxide dismutase activities, and hydrogen peroxide contents in the leaves. The relative abundance of Pedobacter was greater when the SA concentration was high. Pedobacter glucosidilyticus was tolerant to high concentrations of SA. Overall, this study provides insight into ecological antibiotic removal and screening of aquatic plants with SA stress.