Potential Approaches to Improving Biodegradation of Hydrocarbons for Bioremediation of Crude Oil Pollution

With increasing demands of fossil fuel energy, extensive exploration of natural sources has caused a number of large scale accidental spills of crude oil and resulted in some significantly environmental disasters. The consequence of oil pollution to environment and human health has brought a serious challenge to environmental scientists. Physical and chemical approaches to cleanup oil spills are too expensive and create adverse effects. Bioremediation has shown a great potential and competitive privilege because of environment friendly and cost effective. A number of efficient microbial strains have been identified and isolated, which can effectively degrade various components of petroleum oil. However, the biodegradation efficiency is usually limited by abiotic factors, such as temperature and pH, which are hardly to be controlled in the in situ condition but adequate oxygen supply and nutrient balancing are of importance to impact microbial functions. Therefore, this review especially addresses potential approaches to improving bioremediation of crude oil by supplying solid oxygen and adjusting C: N: P ratio to optimize microbial activities in order to improve the effectiveness and efficacy of bioremediation of crude oil pollutants. In addition, it also elucidates advantages of bioremediation, isolation of selective microbial strains, and evaluation of the biodegradation rates.