A Review on the Bioremediation of Petroleum Hydrocarbons: Current State of the Art

Petroleum hydrocarbons (PHC) enter the environment due to exploration, transportation, usage and spills. PHC contamination is of major concern worldwide due to the damage they cause to the environment. Clean up of hydrocarbon-contaminated sites is expensive and time-consuming; however, bioremediation represents a cost-effective and environmentally safe approach to clean up PHC contamination. Many bioremediation strategies can be applied depending on the contaminated site and the surrounding environment. In addition, a variety of technologies are used to assess the efficiency of bioremediation of contaminated environments through analysis of the concentration of the pollutant. Other technologies are applied to study the microbial communities in the contaminated sites since they represent the backbone of any bioremediation process. One of the most convenient technologies in this regard is next-generation sequencing (NGS) since it is cost-effective and provides comprehensive information regarding diversity and therefore bioremediation potential of microbial communities. Bioremediation, however, is not always a straightforward approach, especially when another contaminant (e.g. heavy metals) is associated with PHC. In this chapter, the concept of bioremediation of hydrocarbon-contaminated environments is illustrated. Moreover, the most common technologies applied in bioremediation are explained. In addition, the most recent tools for assessing the microbial ecology are described. Finally, current challenges and limitations of bioremediation are presented.