Biodegradation of Crude Petroleum Oil by Indigenous and Isolated Bacterial Strains

Newly isolated bacterial strains (i.e. Pseudomonas, Bacillus and Micrococcus species) were able to degrade crude oil. In unfertilized soil 30% crude oil was degraded very slowly while 80% of oil was degraded in fertilized soil in the same time duration (i.e. 90 days). During the next 90 days, 60% and 90% of crude oil was degraded in unfertilized and fertilized soil, respectively. Lower fractions of the crude oil were degraded completely and quickly as compared to higher fractions. Addition of nutrients to the soil resulted in the increase in rate of biodegradation of crude oil. A consortium of isolated indigenous cultures removed 80% of the crude oil in 20 days of incubation while the oil contaminated soil seeded with a pure Pseudomonas sp. IES-Ps-1 degraded <5 %.