The impact of long-term contact of Achromobacter sp. 4(2010) with diesel oil – Changes in biodegradation, surface properties and hexadecane monooxygenase activity

A bacterial strain was isolated from soil that was contaminated with diesel oil and was used in our experiments. The strain was then phenotypically, biochemically and genetically tested and named as Achromobacter 4(2011). In order to examine the impact of long-term contact with diesel oil of bacterial cells, the strain was stored under different conditions – on standard nutrient agar plates and on agar plates with 50 μl diesel oil as a sole carbon and energy source. The results clearly indicated that longer contact with diesel oil led to changes in both the bacterial surface and biochemical properties, as well as the hexadecane monooxygenase activity. Moreover, the fatty acid profiles also changed, leading to an increased content of saturated fatty acids. In addition, the rates of biodegradation of diesel oil were higher even when supplemented with the surfactants – rhamnolipids and saponins. This work demonstrates that prolonged contact of microorganisms with diesel oil can lead to many changes, not only in biodegradation potential, but also in their surface and genetic properties.

► Long-term contact of bacterial strain with diesel oil changes strain's properties. ► Different storage conditions influence the biodegradation efficiency. ► Saturated fatty acids domination was observed during diesel oil biodegradation. ► Rhamnolipids more than saponins modify bacterial cell surface properties.