Comparative adaptation of B. subtilis and P. aeruginosa in diesel supplemented medium and impact on biodegradation potential

Abstract

The degree of diesel blending is likely to influence its toxicity as well as the susceptibility and speed of biodegradation. It is therefore imperative to identify strains that can degrade diesel blend in record time, such as to minimize the impact on the environment. In this study the response of Bacillus subtilis and Pseudomonas aeruginosa to induced tolerance to diesel is comparatively analyzed and the implication on the biodegradation of blended diesel investigated using the gravimetric analysis method. Results show that biodiesel promotes the degradation of diesel blend; however the induction of resistance affects differently the biodegradation potential of B. subtilis and P. aeruginosa. From two weeks to eight weeks induction time, there was increase of the biodegradation capabilities of B. subtilis, 213 % for B0, 24 % for B10 and 62 % for B50, while the biodegradation potential of P. aeruginosa decreased: 17% for B0, 60% for B10, 51% for B50. The induction of tolerance to diesel could therefore be exploited to improve the biodegradation potential of B. subtilis, but further treatment will certainly be required for P. aeruginosa