Biodegradation potential of Serratiamarcescens for diesel/biodiesel blends

• The Serratia marcescens strain was isolated from harbor water and showed the ability to grow on diesel and biodiesel blends.
• The bacterium used the B5 blend rather than the B10, B25 or B100 blends as the sole carbon source.
• The preference for B5 can be explained due to the regular discrete oil spills the bio-prospected area suffers from.
• S. marcescens has high potential for degrading diesel/biodiesel blends.
• S. marcescens has high potential for use in applications in environmental remediation.

Biodiesel is considered to be a natural substitute for petroleum. Moreover, its low toxicity and susceptibility to microbial biodegradation as compared to fossil diesel could reduce the impact on ecosystems in the event of an accidental spill. However, there is a paucity of studies in this field. Thus in the present study, the diesel/biodiesel biodegradation potential of the Serratia marcescens strain 110 UFRGS, isolated from a harbor in southern Brazil, was investigated, using a mineral medium containing the following diesel/biodiesel blends: B5, B10, B25 or B100. The isolate exhibited the lowest increase in CFU mL−1 and cell hydrophobicity in the treatment of B100. Infrared spectroscopy showed high percentages of biodegradation of the biodiesel blends, and B100 showed good biodegradability by the isolate under test. S. marcescens strain 110 UFRGS also displayed the presence of alkB gene. In summary, S. marcescens showed a high diesel/biodiesel degradation rate and is potentially useful for the bioremediation of environments contaminated with diesel/biodiesel.