Abstract
The effects of three typical N-acyl-homoserine lactones (AHLs) on the tolerance of biological nitrogen removal (BNR) system to chronic exposure of zinc oxide nanoparticles (NPs) were investigated. C4-HSL successfully delayed the crash time of nitrogen removal performances in the NP-stressed system, while C6-HSL and C10-HSL maintained total nitrogen removal efficiencies throughout the 90-day NP exposure. All three AHLs increased NPs’ contents captured in extracellular polymeric substances, alleviating membrane damage and preserving floc structure. The activities of tricarboxylic acid cycle-related enzymes and the relative abundances of BNR-related functional genes and genera were significantly enhanced. Besides, C6-HSL and C10-HSL augmented antioxidant enzyme activities and the abundances of functional genes and metabolites related to antioxidation, flagellar assembly, and chemotaxis, which synergistically reduced the reactive oxygen species’ excessive accumulation. The tested AHLs effectively enhanced BNR systems’ tolerance to chronic NP exposure, providing inspiration for quorum sensing applications in emerging contaminant removal.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have