Removal of typical antibiotics from the symbiotic system of Microcystis aeruginosa and emergent plants

Abstract

In a simulated urban river system, the conversion and distribution of six typical antibiotics were investigated under the following conditions: no plant, only Microcystis aeruginosa (algae) and algae combined with Juncus effusus, Cyperus alternifolius, and Acorus calamus. Through the calculation of the mass balance, the quantitative distribution of antibiotics in the water phase, sediment, Microcystis aeruginosa, and plant tissues, and the total elimination efficiency of the antibiotics were determined. The results showed that higher concentrations of sulfathiazole (STZ) and sulfamethoxazole (SMZ) were detected in the water phase of the non-plant group, which were 52.81% and 56.88%, respectively, and ciprofloxacin (CIP) and tetracycline (TCY) were detected higher in the sediment, up to 1562 ng/g and 1829 ng/g, respectively. The antibiotic removal rates have been greatly improved, and those in the system containing Microcystis aeruginosa were higher than that in the system without aquatic plants or algae. The calculation of the mass balance showed that the removal effect of algae combined with Juncus effusus was the best, and the removal rates (azithromycin (AZM) and clarithromycin (CLM)) were the highest, reaching 68.88% and 61.96%. It seems that algae and plants play an important role in the removal of antibiotics.