Molecular identification of crude oil-degrading bacteria isolated from polluted sites in Algeria

Abstract

The petroleum industry in Algeria takes a predominant place in the econo-my. This industry amplifies the environmental contamination and affects microbial diversity of soils. Bioremediation is a cost-effective and efficient process for removing hydrocarbon pollutants. The aim of the study was to isolate cultivable telluric bacteria and to assess their potential as bioremedi-ation agents against the contamination of petroleum hydrocarbons. Crude oil polluted soil samples were taken from different oil refinery in Algeria. Elemental analysis was determined by inductively coupled plasma optical emission spectrometry (ECP-OES). The screening of bacteria degrading hy-drocarbons was studied with oil spreading technique on mineral salt medium (MSM agar) supplemented with crude oil as the only carbon source and en-ergy for direct visualization of clear zones on agar plates. Among the isolates, ten were selected for their degradation potential based on their large clear zone (from 0.5 to 3.2 Cm) for phenotypic and genotypic characterization. Molecular identification was performed by sequencing the gene encoding 16s rRNA. The comparison of sequences with GenBank database showed similarity with different strains Aeromonas hydrophila, Stenotrophomonas maltophilia, Enterobacter xiangfangensis, Pseudomonas aeruginosa, Serratia marcescens, and Raoultella sp. These results are significant for the applica-tion of these isolates at the environmental scale in bioremediation of pollut-ed soils.