Isolation, Characterization, and Comparative Biodegradation Efficiency of Oil-degrading Bacteria from Oil-contaminated Environments

Soil is an important component of the ecosystem which supports life and provides an avenue for crops to grow. It harbors water bodies, holds important mineral resources, elements and supplements that help plants to grow and flourish. Pollution caused by petroleum hydrocarbons (PHs) and its derivatives significantly affect soil and its properties causing great health risks to animals and humans. Several remediation methods had been explored and were continuously used to mitigate the effects caused by different pollutants. These methods such as biostimulation and bioaugmentation merely enrich autochthonous microorganisms. However, traditional remediation methods have proven to be inadequate in completely mitigating pollution leading to growing interest in finding strategies more effective and sustainable. This study compares the efficiency of isolated species against different petroleum hydrocarbon products at successive intervals and establishes more efficient degradation specie at each time interval for each product. The present study results revealed that Streptococcus spp was more efficient for petrol and diesel with efficiency degradation of 96.93% and 83.10% respectively. Pseudomonas spp was found to be the most efficient degrader of engine oil with efficiency degradation of 83.56%. The future direction of researches should focus on identifying the functional genes and pathways enabling these bacterial species to perform degradation process coupled with using the current advancements such as nanotechnology, metagenomics, metabolomics, and genetic engineering to improve the efficiency of the degradation process, reducing the time period of the degradation and also reducing the possibility of the production of more harmful/recalcitrant byproducts by the degradation bacteria.