title: Bacterial mineralization of phenanthrene on thermally activated palygorskite: A14C radiotracer study.
abstract: Clay-bacterial interaction can significantly influence the biodegradation of organic contaminants in the environment. A moderate heat treatment of palygorskite could alter the physicochemical properties of the clay mineral and thus support the growth and function of polycyclic aromatic hydrocarbon (PAH)-degrading bacteria. By using14C-labelled phenanthrene and a model bacterium Burkholderia sartisoli, we studied the mineralization of phenanthrene on the surface of a moderately heat-treated (up to 400°C) palygorskite. The heat treatment at 400°C induced a reduction of binding sites (e.g., by the elimination of organic matter and/or channel shrinkage) in the palygorskite and thus imparted a weaker sequestration of phenanthrene on its surface and within the pores. As a result, a supplement with the thermally modified palygorskite (400°C) significantly increased (20-30%; p<0.05) the biomineralization of total phenanthrene in a simulated soil slurry system. These results are highly promising to develop a clay mineral based technology for the bioremediation of PAH contaminants in water and soil environments.
authors.affiliation: Future Industries Institute, University of South Australia, Mawson Lakes Campus, SA 5095, Australia; Cooperative Research Centre for Contamination Assessment and Remediation of the Environment, ACT Building, University of Newcastle, Callaghan, NSW 2308, Australia. Electronic address: b.nanda.biswas@gmail.com.
authors.forename: Bhabananda
authors.initials: B
authors.lastname: Biswas
authors.affiliation: Future Industries Institute, University of South Australia, Mawson Lakes Campus, SA 5095, Australia. Electronic address: binoy.sarkar@unisa.edu.au.
authors.forename: Binoy
authors.initials: B
authors.lastname: Sarkar
authors.affiliation: Cooperative Research Centre for Contamination Assessment and Remediation of the Environment, ACT Building, University of Newcastle, Callaghan, NSW 2308, Australia; Global Centre for Environmental Remediation (GCER), Faculty of Science and Information Technology, University of Newcastle, Callaghan, NSW 2308, Australia. Electronic address: ravi.naidu@newcastle.edu.au.
authors.forename: Ravi
authors.initials: R
authors.lastname: Naidu
mesh_terms: D000538:Aluminum Silicates; D001419:Bacteria / Q000378:metabolism; D001673:Biodegradation, Environmental; D000077215:Clay; D017616:Magnesium Compounds; D008903:Minerals; D010616:Phenanthrenes / Q000378:metabolism*; D017655:Silicon Compounds; D012989:Soil Pollutants / Q000378:metabolism*
chemical_list: D000538:Aluminum Silicates; D017616:Magnesium Compounds; D008903:Minerals; D010616:Phenanthrenes; D017655:Silicon Compounds; D012989:Soil Pollutants; D000077215:Clay; C026325:attapulgite
keywords: (14)C radiotracer; Bioremediation; Clay-bacterial interaction; Heat treatment; Palygorskite; Polycyclic aromatic hydrocarbon (PAH)