Isolation of Pseudomonas aeruginosa, a Potential Petroleum Hydrocarbon Degrading Bacterium from Waste Water in Sri Lanka

Abstract

Petroleum hydrocarbon contamination of aquatic environments is of great concern as it possesses adverse negative impacts on the natural environment. Bioremediation is a potential alternative in remediation of contaminated habitats which uses the natural biological activity through microbial degradation of contaminants. Pseudomonas aeruginosa, a Gram negative, aerobic rod bacterium which is able to degrade hydrocarbon has high potential in crude oil bioremediation. In view of that, petroleum hydrocarbon degrading bacteria were isolated from wastewater collected from Beira Lake and Parliament Lake into a mineral medium containing burnt oil as the hydrocarbon source. Biochemical characterization and Gram's staining were done to select the interested bacterium. Most of the isolated bacterial colonies were gram negative with rod shaped cells. Genomic DNA extracted from the selected bacterial colonies was used in PCR amplification with specific primers designed for the organism. Four bacterial colonies were identified from both Beira Lake and Parliament Lake to be Pseudomonas aeruginosa. Amplified products were sequenced and one of the isolated organisms was confirmed to be Pseudomonas aeruginosa strain B 136-3 3.