Characterization of 4T Engine Oil Degrading Indigenous Bacteria Isolated From Semi Arid Zone of Rajasthan (Churu)

Abstract

The biodegradation potential of petroleum hydrocarbons such as polycyclic aromatic hydrocarbons (PAHs) and n-branched alkanes etc. of 4T engine oil were evaluated in aqueous media using bacterial strain isolated from petroleum contaminated soil of semi Arid region (Churu) of Rajasthan (India). Out of 12 petroleum hydrocarbons degrading bacterial strain one of the most growing bacteria was identified as Achromobacter xylosoxidans M66 by morphological, physiological, biochemical and partial sequencing of 16s rDNA. This strain was capable to degrade 68 ± 2% of n-alkanes, 28 ± 4% PAHs, and the abiotic loss was 20 ± 2% during 28 days incubation period. 64 ± 3% of n-alkanes and 26 ± 3% PAHs were biodegraded and abiotic loss during this period was 21 ± 3% in 35 days of incubation. As expected abiotic losses were decreases with increasing long chain alkanes and PAH’s concentration. Correlation between cell number and biodegradation rate showed that as the number of cell increased the degradation rate is also increased. The hydrocarbon contents were measured by Gas chromatography Mass spectroscopy (GC-MS) QP-2010 plus Shimadzu) carriedColumn-Rtx-5 MS, 30-meter X 0.25 mm i.d. X 0.25 μm film thickness, 1 ml/min; pressure 72.6 kPa and split ratio 10%. The initial temperature was 60ºC kept for 6 minutes and final temperature for 260ºC was kept for 20 minutes with total running time of 50 minutes.