Effects of antimicrobials in anammox mediated systems: critical review

Abstract

Anammox-mediated systems are thought to be cost-effective and efficient technologies for removing nitrogen from wastewater by converting nitrite and ammonium into dinitrogen gas. However, there are inhibitory substances that reduce the effectiveness and efficiency of these processes, preventing their widespread application. Antimicrobial agents are among these substances that have been observed to inhibit anammox-mediated processes. Therefore, this review provides a comprehensive overview of the effects of various antimicrobials on the anammox-based systems with emphasis on the effects in different reactor configurations, sludge types and microbial population of anammox-based systems. In addition, this review also discusses the mechanisms by which nitrifying bacteria are inhibited by the antimicrobials. Gaps in knowledge based on this review as well as future research needs have also been suggested. This review gives a better knowledge of antimicrobial effects on anammox-based systems and provides some guidance on the type of system to use to treat antimicrobial-containing wastewater using anammox-based processes.

Nitrogen Removal Performance and Microbial Response of Anammox Under Multiantibiotic Stress: Effect of Static Magnetic Field

“…The results demonstrated that multiantibiotic exposure inhibited TN removal performance in the anammox process, especially under high nitrogen load conditions, and the inhibition tended to be irreversible. Anammox inhibition by OTC is reportedly caused by cell membrane damage and protein synthesis inhibition, while SDZ inhibits bacterial growth and reproduction by competing with p -aminobenzoic acid in the enzymatic synthesis of dihydrofolic acid. , Nevertheless, the impacts of OTC or SDZ on anammox depend on the antibiotic concentration. Anammox was reportedly inhibited when the OTC concentration reached 2 mg/L .…”

“…Anammox inhibition by OTC is reportedly caused by cell membrane damage and protein synthesis inhibition, while SDZ inhibits bacterial growth and reproduction by competing with p-aminobenzoic acid in the enzymatic synthesis of dihydrofolic acid. 8,29 Nevertheless, the impacts of OTC or SDZ on anammox depend on the antibiotic concentration. Anammox was reportedly inhibited when the OTC concentration reached 2 mg/L.…”

“…However, anammox bacteria are known for their slow growth rates, resulting in a long startup period and fluctuating nitrogen removal efficiency during the anammox process. Anammox process is sensitive to a variety of factors, including substrate, temperature, organic matter, and inhibitors. , Particularly, antibiotics in wastewater hinder the biological processes and microbial activity; thus, anammox inhibition has been the subject of numerous investigations. − The anammox response to antibiotics includes microbial population succession, ARGs accumulation, and extracellular polymeric substance (EPS) formation . An anammox granule is a consortia composed of large numbers of microorganisms, with anammox bacteria as the core and other functional bacteria (including heterotrophic denitrifies, ammonia oxidizing bacteria, and fermentative bacteria) as the symbiotic microorganism .…”

Effect of Operating Parameters on the Performance of Integrated Fixed-Film Activated Sludge for Wastewater Treatment

“…Higher temperatures promote the growth of thermophilic bacteria, which degrade certain compounds more efficiently. However, extreme temperatures, both hot and cold, have negative impacts on microbial activity and reduce treatment performance [ 98 , 99 ].…”