Enhanced anoxic bioremediation of PAHs-contaminated sediment
PAHs, Biodegradation, Anoxic conditions, Nah Ac cene
In this study, the biodegradation of 16 polycyclic aromatic hydrocarbons (PAHs) in marine sediment was investigated under three different anoxic conditions, i.e. sulfate-only, nitrate-only and mixed nitrate/sulfate as electron acceptors. All two-, three- and four-ring PAHs showed significant biodegradation with the removal efficiencies ranging from 42% to 77%, while five- and six-ring PAHs showed little degradation. The results illustrated that two- to three-ring PAHs could be degraded at a rate of 4.01×10−2–6.42×10−2d−1 under nitrate-reducing condition, faster than that of under sulfate-reducing condition. Biodegradation of two- and three-ring PAHs followed first-order model well with the rate constants of 1.62×10−2–6.42×10−2d−1. The biodegradation of four ring PAHs followed the zero-order kinetic model with the rate constants of 1.26×10−2–2.22×10−2mg/kg/d. Molecular analysis indicated that nahAc gene increased by two orders of magnitude during the biodegradation and served as a good indicator of PAHs-degrading bacterial population and biodegradation process.
Lu, X.,Li, B.,Zhang, T.,& Fang, H. (2012). Enhanced anoxic bioremediation of PAHs-contaminated sediment. Bioresource Technology, 104, 51-58. http://dx.doi.org/10.1016/j.biortech.2011.10.011