Study of petrol degrading bacteria and screening for biosurfactants

Petroleum-based products when mixed with soil, air and water can lead to environmental pollution which can be dangerous for humans. In the current study, soil samples from the petrol unloading area of a petrol pump were collected and nine isolates of petrol degrading bacteria were isolated from the soil by enrichment technique using Bushnell and Hass media. The isolated bacteria could degrade up to 5% petrol and the best degraders were chosen after evaluating their cell mass when grown in the presence of petrol. The percentage of petrol degraded after different intervals of incubation was compared using a UV-vis double beam spectrometer at 228 nm. It was found that the two bacteria - Pseudomonas aeruginosa and Burkholderia cepacia degraded petrol 94.96% and 94.74%, respectively, by day 15 of incubation. The percentage degradation gradually decreased by day 20. Both bacteria were also screened for the production of biosurfactants through haemolysis. It was found that both the bacteria could produce biosurfactant along with them being a potent petrol degrader.