Simultaneous aerobic denitrification and Cr(VI) reduction by Pseudomonas brassicacearum LZ-4 in wastewater
Xuan Yu1, Yiming Jiang2, Haiying Huang2
1Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Science, Lanzhou University, Tianshuinanlu #222, Lanzhou, Gansu 730000, PR China; Gansu Academy of Membrane Science and Technology, Duanjiatanlu #1272, Lanzhou, Gansu 730020, PR China; School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou, Jiangsu 221116, PR China.
Abstract:
Inorganic nitrogen and heavy metals pervasively co-exist in industrial and domestic wastewaters. In this work, Pseudomonas brassicacearum LZ-4 was tested for the simultaneous reduction of Cr(VI) and nitrate. Nitrate was found to be the best inorganic nitrogen source for strain LZ-4, and could promote Cr(VI) reduction. Cr(VI) had a low degree of inhibition on denitrification, and even 50mgL-1 Cr(VI) did not inhibit reduction of 100mgL-1 NO3--N. The capability of simultaneous reduction of Cr(VI) and nitrate was illustrated by the reductase genes contained in the LZ-4 genome. Application in a batch membrane bioreactor showed that the immobilized strain LZ-4 could remove over 95% of 500mgL-1 NO3--N, 80% of 10mgL-1 Cr(VI), and 96% of 5000mgL-1 COD in each batch of 46days. In summary, the strain LZ-4 is an ideal candidate for remediation of co-contaminants.
More Related Videos
Related Concept Videos
Bioremediation
Environmental Applications of Microorganisms
Metabolism of Chemolithotrophs


