title: Efficient degradation of lube oil by a mixed bacterial consortium.
abstract: A laboratory study was performed to assess the biodegradation of lube oil in bio-reactor with 304# stainless steel as a biofilm carrier. Among 164 oil degrading bacterial cultures isolated from oil contaminated soil samples, Commaonas acidovorans Pxl, Bacillus sp. Px2, Pseudomonas sp. Px3 were selected to prepare a mixed consortium for the study based on the efficiency of lube oil utilization. The percentage of oil degraded by the mixed bacterial consortium decreased slightly from 99% to 97.2% as the concentration of lube oil was increased from 2000 to 10,000 mg/L. The degradation of TDOC (total dissolved organic carbon) showed a similar tendency compared with lube oil removal, which indicated that the intermediates in degradation process hardly accumulated. Selected mixed bacterial consortium showed their edge compared to activated sludge. Scanning electron microscopy (SEM) photos showed that biofilms on stainless steel were robust and with a dimensional framework constructed by EPS (extracellular polymeric substances), which could promote the biodegradation of hydrocarbons. The increase of biofilm followed first-order kinetics with rate of 0.216 microg glucose/(cm2-day) in logarithm phase. With analysis of Fourier transform infrared spectroscopy (FT-IR) and gas chromatography-mass spectrometry (GC-MS) combined with removal of lube oil and TDOC, mixed bacterial consortium could degrade benzene and its derivatives, aromatic ring organic matters with a percentage over 97%.
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China. whf0515@126.com
authors.forename: Haifeng
authors.initials: H
authors.lastname: Wang
authors.forename: Ran
authors.initials: R
authors.lastname: Xu
authors.forename: Fengting
authors.initials: F
authors.lastname: Li
authors.forename: Junlian
authors.initials: J
authors.lastname: Qiao
authors.forename: Bingru
authors.initials: B
authors.lastname: Zhang
mesh_terms: D001419:Bacteria / Q000378:metabolism*; D001673:Biodegradation, Environmental; D018441:Biofilms; D019149:Bioreactors; D008401:Gas Chromatography-Mass Spectrometry; D007501:Iron; D008855:Microscopy, Electron, Scanning; D010578:Petroleum / Q000378:metabolism*; D012989:Soil Pollutants / Q000737:chemistry / Q000378:metabolism; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D010578:Petroleum; D012989:Soil Pollutants; D007501:Iron