Ciprofloxacin, diclofenac, ibuprofen and 17α-ethinylestradiol differentially affect the activity of acetogens and methanogens in anaerobic communities

Abstract

Pharmaceutical compounds end up in wastewater treatment plants but little is known on their effect towards the different microbial groups in anaerobic communities. In this work, the effect of the antibiotic Ciprofloxacin (CIP), the non-steroidal anti-inflammatory drugs Diclofenac (DCF) and Ibuprofen (IBP), and the hormone 17α-ethinylestradiol (EE2), on the activity of acetogens and methanogens in anaerobic communities, was investigated. Microbial communities were more affected by CIP, followed by EE2, DCF and IBP, but the response of the different microbial groups was dissimilar. For concentrations of 0.01 to 0.1 mg/L, the specific methanogenic activity was not affected. Acetogenic bacteria were sensitive to CIP concentrations above 1 mg/L, while DCF and EE2 toxicity was only detected for concentrations higher than 10 mg/L, and IBP had no effect in all concentrations tested. Acetoclastic methanogens showed higher sensitivity to the presence of these micropollutants, being affect by all the tested pharmaceutical compounds although at different degrees. Hydrogenotrophic methanogens were not affected by any concentration, indicating their lower sensitivity to these compounds when compared to acetoclasts and acetogens.

Anaerobic Digestion and Removal of Sulfamethoxazole, Enrofloxacin, Ciprofloxacin and Their Antibiotic Resistance Genes in a Full-Scale Biogas Plant

“…The effect of ciprofloxacin on the activity of acetogens and methanogens in anaerobic communities was investigated by Silva et al [ 35 ], who found acetogenic bacteria to be sensitive to ciprofloxacin concentrations above 1 mg/L, while hydrogenotrophic methanogens were not affected by any CIP concentration. Other authors [ 36 ] found that CIP caused a significant disturbance of anaerobic digestion at concentrations between 0.5 to 50 mg/L.…”

Effects of Ciprofloxacin Alone or in Mixture with Sulfamethoxazole on the Efficiency of Anaerobic Digestion and Its Microbial Community

“…A number of previous studies reported the effects of antibiotics on the Bacteria and Archaea domains [ 26 , 27 , 37 ], showing that macrolides inhibited more methanogens than Bacteria , in particular acetoclastic. Moreover, it must be considered that the Archaea component of the AD microbial community thrives by relying on Bacteria metabolism.…”

“…SMX is a bacteriostatic antibiotic that primarily inhibits bacterial growth and reproduction by acting on folic acid synthesis [ 24 ]. Several studies evaluated the effects of CIP [ 25 , 26 , 27 ] and SMX on AD performance [ 28 , 29 ] and its microbial community. Although this research is of great interest, usually more than one antibiotic is detected in manure or digestate [ 17 ].…”

Effect of Carbamazepine, Ibuprofen, Triclosan and Sulfamethoxazole on Anaerobic Bioreactor Performance: Combining Cell Damage, Ecotoxicity and Chemical Information

“…Some previous works also evaluated the effect of several pharmaceuticals on AD, where attention is specially focused on biogas production, but not to organic matter removal. In this manner, it was proven in the literature that IBU inhibits acetoclastic methanogens but does not cause inhibition to other trophic groups involved in the anaerobic process [49].…”