TY - JOUR
T1 - Long-term effect of the antibiotic cefalexin on methane production during waste activated sludge anaerobic digestion
AU - Lu, Xueqin
AU - Zhen, Guangyin
AU - Liu, Yuan
AU - Hojo, Toshimasa
AU - Estrada, Adriana Ledezma
AU - Li, Yu You
N1 - Funding Information:
The authors wish to thank the China scholarship council ( CSC ) for the partial support of this study.
Publisher Copyright:
© 2014 Elsevier Ltd.
PY - 2014/10/1
Y1 - 2014/10/1
N2 - Long-term experiments herein were conducted to investigate the effect of cefalexin (CLX) on methane production during waste activated sludge (WAS) anaerobic digestion. CLX exhibited a considerable inhibition in methane production during the initial 25. days while the negative effect attenuated subsequently and methane production recovered depending on CLX doses used (600 and 1000. mg/L). The highest methane yield reached 450. mL at 1000. mg-CLX/L after 157. days of digestion, 63.8% higher than CLX-free one. Stimulated excretion of extracellular polymeric substances (EPS) by CLX served as microbial protecting layers, creating a suitable environment for microbes' growth and fermentation. Further examination via ultraviolet visible (UV-Vis) spectra also verified the elevated slime EPS, LB-EPS and TB-EPS indicated by UV-254 in the presence of CLX. Unlike the commonly accepted adverse effect, this study demonstrated the beneficial role of CLX in methane production, providing new insights into its true environmental impacts.
AB - Long-term experiments herein were conducted to investigate the effect of cefalexin (CLX) on methane production during waste activated sludge (WAS) anaerobic digestion. CLX exhibited a considerable inhibition in methane production during the initial 25. days while the negative effect attenuated subsequently and methane production recovered depending on CLX doses used (600 and 1000. mg/L). The highest methane yield reached 450. mL at 1000. mg-CLX/L after 157. days of digestion, 63.8% higher than CLX-free one. Stimulated excretion of extracellular polymeric substances (EPS) by CLX served as microbial protecting layers, creating a suitable environment for microbes' growth and fermentation. Further examination via ultraviolet visible (UV-Vis) spectra also verified the elevated slime EPS, LB-EPS and TB-EPS indicated by UV-254 in the presence of CLX. Unlike the commonly accepted adverse effect, this study demonstrated the beneficial role of CLX in methane production, providing new insights into its true environmental impacts.
KW - Cefalexin
KW - Extracellular polymeric substances (EPS)
KW - Methane production
KW - Ultraviolet visible (UV-Vis) spectra
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U2 - 10.1016/j.biortech.2014.07.056
DO - 10.1016/j.biortech.2014.07.056
M3 - Article
C2 - 25105270
AN - SCOPUS:84921355073
SN - 0960-8524
VL - 169
SP - 644
EP - 651
JO - Bioresource Technology
JF - Bioresource Technology
ER -
