Ability of Pseudomonas aeruginosa and Bacillus subtilis to remove petroleum hydrocarbons

Abstract

Two strains of bacteria have been studied to remove crude oil in vitro. These were Pseudomonas aeruginosa and Bacillus subtilis. The results showed that both P.aeruginosa and B.subtilis have ability to remove petroleum hydrocarbons in mineral salts medium, but P.aeruginosa was more efficient in the bioremediation of crude oil than B.subtilis in mineral salts medium. The results obtained tha the higher number of bacteria was calculated with P.aeruginosa in solid medium with presence of crude oil, and the number of this bacteria reached 26.7 x 108, but the lowest number was recorded in solid medium without added crude oil (control), the number reached 4 x 107.The statistical methods showed that no significant were recorded between different treatments. The results also showed that the higher number of B.subtilis was calculated in solid medium with the presence of petroleum hydrocarbons, and the number of these bacteria reached 20.4 x 108, but the lowest number of bacteria was recorded in solid medium without added crude oil (control), the number reached 1 x 107. The statistical methods showed that no significant were recorded between different treatments. The results showed that the axenic cultures of bacteria were degraded petroleum hydrocarbons in mineral salts medium, and many bands disappeared when compared with control (UN inoculated). The purpose of this study, therefore it was necessary to investigate the ability of P.aeruginosa and B.subtilis to bioremediate crude oil.