Anaerobic nitrate reduction with oxidation of Fe(II) by Citrobacter Freundii strain PXL1 - a potential candidate for simultaneous removal of As and nitrate from groundwater
Journal
Ecological Engineering
Journal Volume
77
Pages
196-201
Date Issued
2015
Author(s)
Abstract
Nitrate and arsenic are common pollutants in groundwater. However, we are still lacking technologies that can remove nitrate and arsenic simultaneously using a single species of microorganism. In the present study, the potential of synchronous removal of nitrate and arsenite from water by a single anaerobic nitrate-reducing Fe(II) oxidizing Citrobacter freundii strain PXL1 was assessed. The strain PXL1 could grow well in arsenite concentration of 2.85-13.65. £gM and efficiently oxidize Fe(II), reduce nitrate and remove As(III) from water. Scanning electron microscopy, X-ray diffraction spectroscopy, and Fourier transform infrared spectroscopy analysis showed that the strain PXL1 produced poorly crystalline Fe(III) oxides. As(III) was removed mainly by adsorption and co-precipitation of the biogenic Fe(III) oxides. The anaerobic nitrate-dependent Fe(II) oxidizing bacteria including C. freundii PXL1 are promising microbes for in situ remediation of nitrate and arsenite contaminated groundwater. ? 2015 Elsevier B.V.
Subjects
As(III) removal
Biogenic iron oxides
Ferrous iron oxidizing bacteria
Nitrate reduction
Type
journal article