Effect of Metal Ions on Naphthalene Degrading Ability of Bacteria Isolated from Oil Contaminated Soils

Abstract

Polyaromatic hydrocarbons (PAHs) entering into the environment from various sources are highly toxic and deleterious to living beings. Naphthalene is one the sixteen toxic PAHs enlisted by EPA, US. Physical and chemical methods used for the removal of PAHs from polluted sites are not effective. Bioremediation which employs microbes to metabolize PAHs is an alternative method to physical and chemical processes. Naphthalene is considered as model compound for the biodegradation studies of PAHs. In the present study the effect of seven selected metal ions on naphthalene degrading ability of three bacterial species (viz., Bacillus, Pseudomonas and Micrococcus) isolated from oil contaminated soils of mechanical was studied. Five metal ions were reported to enhance the naphthalene degrading activity and two found to decrease the activity. These bacteria can be further improved and used for bioremediation of polluted sites.