Integrated approach to enhance the anaerobic biodegradation of benz[α]anthracene: A high-molecule-weight polycyclic aromatic hydrocarbon in sludge by simultaneously improving the bioavailability and microbial activity

• Published in: Journal of hazardous materials 2019-03, Vol.365, p.322-330
• Main Authors: Luo, Jingyang, Wu, Lijuan, Chen, Yinguang, Feng, Leiyu, Cao, Jiashun
• Format: Article
• Language: English
• Subjects: Alkaline treatment; alkyl polyglucosides (APG); Benz[α]anthracene (BaA); Bioavailability; Microbial activities
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2018.11.012

[Display omitted] •High BaA biodegradation efficiency was achieved by alkaline pH and APG treatment.•Alkaline pH and APG could effectively improve the bioavailability of BaA.•The released substrates accelerated the electron transfer during BaA degradation.•The activity of bacteria responsible for BaA degradation was evidently stimulated.•The typical fermentative bacteria involved in the BaA degradation. The biodegradation of benz[α]anthracene (BaA), which was a high-molecule-weight PAH, was enhanced via a combination of alkaline and alkyl polyglucosides (APG) treatment during waste activated sludge (WAS) anaerobic fermentation. The biodegradation efficiency of BaA was increased from 14.1% in the control to 30.2 and 47.8% in pH 10 and pH 10 & APG reactors, respectively. Mechanism investigations found that the alkaline and APG treatments stimulated the processes of BaA desorption from sludge and transfer/entry into microorganisms, and ultimately improved the BaA bioavailability. Meanwhile, the huge released substrates from WAS not only served as carbon sources but also involved in the electron transfer among microorganisms which contributed to the BaA biodegradation process. Moreover, the microbial activities involved in BaA biodegradation, including the abundances of functional bacteria, activities of enzymes and quantities of genes, were also incremented due to the alkaline and APG treatments. Overall, the simultaneous improvement of BaA bioavailability and microbial activities enhanced its biodegradation efficiency.