Effects of Antibiotics on Methane Production from Cellulose

Abstract

Developing methods to enhance methane production from cellulose is vital for anaerobic digestion (AD) of lignocellulosic biomass. Antibiotics can motivate AD performance by changing the microorganism activity. However, few researches focused on its effect on AD of cellulose. Herein, the effects of antibiotics, including tetracycline (TC), azithromycin (AZM) and cephalexin (CLX), on the AD of cellulose inoculated with waste sewage sludge (WSS) were investigated. Consequently, 51.94%, 34.96% higher methane yields were observed in the presence of AZM and TC, respectively, while 23.95% lower methane yield was observed in the presence of CLX, compared to the control during 20 days’ AD. Further analyses showed that AZM addition stimulated AD of cellulose at all stages including hydrolysis, acidogenesis/acetogenesis and methanogenesis, while TC addition promoted it mainly at methanogenesis stage. These findings can provide a valuable guidance for efficient methane production from lignocellulosic biomass with the favor of antibiotics.

Keywords: Anaerobic digestion, cellulose, Waste sewage sludge, Antibiotics, Microbial community