Detoxification of Mercury by Bacteria Using Crude Glycerol from Biodiesel as a Carbon Source

• Published in: Water, air, and soil pollution air, and soil pollution, 2015-07, Vol.226 (7), p.481-13, Article 224
• Main Authors: Giovanella, P., Costa, A. P., Schäffer, N., Peralba, M. C. R., Camargo, F. A. O., Bento, F. M.
• Format: Article
• Language: English
• Subjects: Arthrobacter; Atmospheric Protection/Air Quality Control/Air Pollution; Atomic absorption spectroscopy; Bacteria; Biodegradation; Biodiesel fuels; Biofuels; Bioremediation; Carbon; Carbon sources; Catalysis; Chromosomes; Climate Change/Climate Change Impacts; Contamination; Detoxification; Diesel; Earth and Environmental Science; Effluents; Environment; Environmental degradation; Environmental monitoring; Environmental studies; Enzymes; Fatty acids; Genomics; Glycerol; High performance liquid chromatography; Hydrogeology; Industrial wastes; Klebsiella oxytoca; Klebsiella pneumoniae; Liquid chromatography; Membrane separation; Mercury; Metabolism; Microorganisms; Pathogenicity; Pathogens; Proteins; Ribosomal DNA; Serratia marcescens; Silver; Soil degradation; Soil Science & Conservation; Soil sciences; Spectral analysis; Toxicity; Water Quality/Water Pollution; Yeasts
• ISSN: 0049-6979; 1573-2932
• DOI: 10.1007/s11270-015-2480-9

Bacteria that harbor the mer operon in their genome are able to enzymatically reduce mercury (II) to the volatile form of mercury Hg (0). Detoxification of contaminated waste by using these bacteria may be an alternative to conventional methods for mercury removal. Residual glycerol from the biodiesel industry can be used as a carbon source to accelerate the process. This work shows for the first time the feasibility of using residual glycerol as a carbon source for Hg removal by bacteria prospected from contaminated environments. Eight bacterial isolates were able to remove mercury and degrade glycerol in mineral medium and residual glycerol. Mercury removal was monitored by atomic absorption spectroscopy and glycerol degradation by high performance liquid chromatography. The best results of mercury removal and glycerol degradation were obtained using isolates of Serratia marcescens M25C (85 and 100 %), Klebsiella pneumoniae PLB (90 and 100 %), Klebsiella oxytoca (90 and 100 %), and Arthrobacter sp. U3 (80 and 75 %), with addition of 0.5 g L −1 yeast extract. The Arthrobacter s p. U3 isolate is common in soils and has proven to be a promising candidate for environment applications due to its low pathogenicity and higher Hg removal and glycerol degradation rates.