Bioremediation of petroleum hydrocarbon by mixed bacteria culture of Pseudomonas aeruginosa and Brevibacterium sp.

The intention of this research is to overcome pollution by petroleum using bioremediation method with the help of hydrocarbonoclastic bacteria. The first step in this research was to characterize petroleum as pollutants and cultivate mixed culture bacteria, i.e. Pseudomonas aeruginosa and Brevibacterium sp. The second step was degradation test with growth medium of SMSS (Stone Mineral Salt Solution) with variations pH and concentration. It was conducted in a 300 ml Erlenmeyer series with composition of 80% media, 5% petroleum, and 10% bacteria placed in an incubator shaker with a rotation speed of 200 rpm for 7 days. Based on the results from degradation test with growth medium of SMSS, obtained results that TPH (Total Petroleum Hydrocarbon) degradation efficiency is higher at a pH of 8 that is equal to 28.47%. In the variation of concentration, the highest degradation efficiency occurs at concentration of 20% oil which is reduced oil viscosity up to 22.00%. This research proves that Pseudomonas aeruginosa and Brevibacterium sp. can degrade hydrocarbon composition in petroleum with an efficiency of up to 20%.