title: Concomitant rock phosphate dissolution and lead immobilization by phosphate solubilizing bacteria (Enterobacter sp.).
abstract: This paper examines the potential value of phosphate solubilizing bacteria (Enterobacter cloacae) in the dissolution of rock phosphate (RP) and subsequent immobilization of lead (Pb) in both bacterial growth medium and soils. Enterobacter sp. showed resistance to Pb and the bacterium solubilized 17.5% of RP in the growth medium. Enterobacter sp. did not enhance Pb immobilization in solution because of acidification of bacterial medium, thereby inhibiting the formation of P-induced Pb precipitation. However, in the case of soil, Enterobacter sp. increased Pb immobilization by 6.98, 25.6 and 32.0% with the RP level of 200, 800 and 1600 mg P/kg, respectively. The immobilization of Pb in Pb-spiked soils was attributed to pyromorphite formation as indicated by XRD analysis. Inoculation of phosphate solubilizing bacteria with RP in soil can be used as an alternative technique to soluble P compounds which can cause eutrophication of surface water.
authors.affiliation: Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes, SA 5095, Australia. Jin.Park@unisa.edu.au
authors.forename: Jin Hee
authors.initials: JH
authors.lastname: Park
authors.forename: Nanthi
authors.initials: N
authors.lastname: Bolan
authors.forename: Mallavarapu
authors.initials: M
authors.lastname: Megharaj
authors.forename: Ravi
authors.initials: R
authors.lastname: Naidu
mesh_terms: D016972:Enterobacter cloacae / Q000378:metabolism*; D052918:Environmental Restoration and Remediation / Q000379:methods; D007854:Lead / Q000378:metabolism*; D010710:Phosphates / Q000378:metabolism*; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000378:metabolism*; D014961:X-Ray Diffraction
chemical_list: D010710:Phosphates; D012987:Soil; D012989:Soil Pollutants; D007854:Lead