Polycyclic aromatic hydrocarbon improves the anaerobic biodegradation of benz [α] anthracene in sludge via boosting the microbial activity and bioavailability

Abstract

The biodegradation of benz [α] anthracene (BaA), a high molecular weight polycyclic aromatic hydrocarbons (PAH) was increased via a combination of alkyl polyglucosides and alkaline treatment during the waste activated sludge (WAS) anaerobic fermentation. During the experimental study, the biodegradation efficiency of BaA was enhanced from 12.2% in the control to 25.6% at pH 10 and 46.7% at pH 10 and alkyl polyglucosides (APG) reactors. APG and alkaline treatment increased the BaA deposition desorption from the sludge and transfer into micro-organisms and finally increased the BaA bioavailability. In the meantime, the enormous secretion of substrates from the WAS not only served as carbon source but was also engaged in the electron transfer among the micro-organisms which take part in the BaA biodegradation process. Therefore, the microbial activity also engaged in the biodegradation of BaA like genes quantity, the activity of enzymes and functional of bacteria, were also increased due to the APG and alkaline treatments. Overall, the instantaneous enhancement of microbial activity and BaA bioavailability increased biodegradation efficiency.