Abstract
Bioremediation is known as a natural process which relies on bacteria and fungi to degrade, to breakdown and to remove various contaminants such as petroleum hydrocarbons from soil and water. These microorganisms possess the capability to use petroleum hydrocarbons as energy source and consequently render the contaminants harmless or less toxic. Various substances with known toxic properties are continuously being introduced into the environment due to human activities. These contaminants pose great risk to human health and cause serious damage to environment and biodiversity. Polycyclic aromatic hydrocarbons (PAHs) have been detected in high concentrations at sites that use or process petroleum products. PAHs are found to be carcinogens and very recalcitrant and persist in natural environment for several years.
In this review our main focus is on biodegradation of PAHs (pollutant) by different bacterial and fungal groups and the different pathways that are used by these microbial groups to degrade PAHs. PAHs are not only an environmental hazard but are found to be a good source of energy to these microbes and hence their degradation not only relieves the environment of this environmental pollutant but provides the basic building blocks for microbes to survive. Bioremediation has tremendous potential to provide a cost-effective natural process to render toxic substances in environment harmless overtime.