Brazilian Journal of Microbiology Brazilian Journal of Microbiology
Braz J Microbiol 2018;49:258-68 - Vol. 49 Num.2 DOI: 10.1016/j.bjm.2017.04.014
Environmental Microbiology
Anaerobic biodegradation of benzo(a)pyrene by a novel Cellulosimicrobium cellulans CWS2 isolated from polycyclic aromatic hydrocarbon-contaminated soil
Wei Qina, Fuqiang Fanb, Yi Zhua, Xiaolong Huanga, Aizhong Dinga, Xiang Liuc, Junfeng Doua,,
a Beijing Normal University, College of Water Sciences, Beijing, China
b Memorial University of Newfoundland, Faculty of Engineering and Applied Science, Northern Region Persistent Organic Pollution Control Laboratory, St. John's, Canada
c Tsinghua University, School of Environment, Beijing, China
Received 30 December 2016, Accepted 25 April 2017

Cellulosimicrobium cellulans CWS2, a novel strain capable of utilizing benzo(a)pyrene (BaP) as the sole carbon and energy source under nitrate-reducing conditions, was isolated from PAH-contaminated soil. Temperature and pH significantly affected BaP biodegradation, and the strain exhibited enhanced biodegradation ability at temperatures above 30°C and between pH 7 and 10. The highest BaP removal rate (78.8%) was observed in 13 days when the initial BaP concentration was 10mg/L, and the strain degraded BaP at constant rate even at a higher concentration (50mg/L). Metal exposure experimental results illustrated that Cd(II) was the only metal ion that significantly inhibited biodegradation of BaP. The addition of 0.5 and 1.0g/L glucose enhanced BaP biodegradation, while the addition of low-molecular-weight organic acids with stronger acidity reduced BaP removal rates during co-metabolic biodegradation. The addition of phenanthrene and pyrene, which were degraded to some extent by the strain, showed no distinct effect on BaP biodegradation. Gas chromatography–mass spectrometry (GC-MS) analysis revealed that the five rings of BaP opened, producing compounds with one to four rings which were more bioavailable. Thus, the strain exhibited strong BaP degradation capability and has great potential in the remediation of BaP-/PAH-contaminated environments.

Anaerobic, Biodegradation, Benzo(a)pyrene, Cellulosimicrobium cellulans CWS2
Braz J Microbiol 2018;49:258-68 - Vol. 49 Num.2 DOI: 10.1016/j.bjm.2017.04.014