Biodegradation of Petrochemical Hydrocarbons Using an Efficient Bacterial Consortium: A2457

Abstract

Petrochemical hydrocarbons are considered to be the most significant environmental pollutants and need to be removed. In present study, the biodegradation of used engine oil and diesel oil was achieved under shake flask conditions using an efficient bacterial consortium A2457: comprising bacterial strains of Stenotrophomonas maltophilia, Bacillus cereus and Bacillus pumilus. The strains were isolated and screened by enrichment technique. The bacterial strains were identified on the basis of 16S rRNA gene sequence homology. The percent removal and biodegradation of the petrochemicals was evaluated through UV–Vis spectrophotometer and FTIR spectrometry. The bacterial consortium resulted in significant degradation of diesel oil (94.13 %) and used engine oil (99.77 %) under experimental conditions. FTIR spectra of the hydrocarbons, before and after biodegradation experiments, also revealed significant changes in the characteristic peaks in the wavenumber range of 4000–600 cm−1. The consortium displayed significant biosurfactant production and lipase activity during 28 days of incubation and reduced the surface tension of culture medium to 27.95 ± 0.3 mN m−1. The petrochemical hydrocarbon degradation by the bacterial consortium: A2457 of present study could be attributed with the production of biosurfactants and lipases to utilize diesel oil and used engine oil as sole source of carbon and energy.