J Hazard Mater. 2026 May 14;512:142390. doi: 10.1016/j.jhazmat.2026.142390. Online ahead of print.
ABSTRACT
Antibiotic-containing agricultural wastewater poses a critical challenge for simultaneous pollutant removal and carbon reduction technology. In this study, a visible-light-driven photocatalysis-microalgae (PC-MA) system was constructed by coupling WO3/α-Fe2O3/zeolite (WFZ) heterojunction with Chlorella vulgaris granules to treat simulated wastewater containing ciprofloxacin (CIP). At 20 mg/L CIP concentration, the PC-MA achieved 89% CIP removal over six reuse cycles, and exhibited superior COD, TOC, NH4+ -N, and TP removal compared with the single photocatalytic (PC) and microalgal (MA) systems. Radical quenching and ESR experiments indicated that WFZ generated an intense •OH/O2•⁻ oxidative environment, while LC-MS analysis revealed progressive transformation of CIP into more polar, lower-molecular-weight intermediates that are more amenable to subsequent bioprocessing. The physiological (chlorophyll-a, biomass, and CO2 biofixation rate) and biochemical (EPS fluorescence, oxidative-stress biomarkers, and carbonic anhydrase activity) indicators demonstrated that the PC-MA system relieved CIP-induced oxidative stress and maintained Chlorella in a higher-activity state. Transcriptomic analysis further revealed that the up-regulation of photosynthetic antenna proteins, Calvin cycle enzymes, and carbonic anhydrase-related genes enhanced photosynthetic carbon fixation under CIP exposure. The photocatalysis-biodegradation synergistic relationship offered a sustainable route for the simultaneous antibiotic removal and transformation, nutrient removal, and enhanced carbon assimilation in complex wastewater treatment.
PMID:42139784 | DOI:10.1016/j.jhazmat.2026.142390