Phylogeny and polycyclic aromatic hydrocarbons degradation potential of bacteria isolated from crude oil-contaminated site

摘要

This study employed the use of 16S rRNA gene sequence analysis to identify three of four native bacterial strains isolated from crude oil-contaminated site in Poza Rica, Veracruz, Mexico. The identified bacteria were Ochrobactrum intermedium, Pandoraea pnomenusa and Ochrobactrum sp., but SA2-09 strain was not identified. The ability of the isolates to degrade polycyclic aromatic hydrocarbons (PAHs) was evaluated at 31.61 and 54.52mg/kg PAHs in soil, when used as crude oil in soil microcosm during 80days of incubation at 30 degrees C. The results demonstrated that O. intermedium biodegraded many PAHs, including the high molecular weight (HMW) PAHs fluoranthene (100% equivalent 0.24mg/kg), benzo [b] fluoranthene (81.8% equal 0.18mg/kg), Benzo[a]pyrene (87.0%, 0.20mg/kg) and Benzo[g,h,i]perylene (52.7%, 0.39mg/kg). P. pnomenusa had a degradation profile of HMW PAHs, which was similar to O. intermedium, while Ochrobactrum sp. and the strain SA-09 exhibited lower degradation rates of HMW.