Journal of Pure and Applied MicrobiologyVol. 9 No. 4

Isolation and Characterization of Non-Adapted BTEX Degrading Bacterial Strains from Petroleum Contaminated Environment

S. Sheeba Varma, M. Brinda Lakshmi and M. Velan*

Department of Chemical Engineering, Alagappa College of Technology, Anna University, Chennai 600025, India.

Received on 28 September 2015 and accepted on 15 November 2015

 

ABSTRACT

The volatile monoaromatic hydrocarbons BTEX have been termed and considered as environmental pollutants. In this study, the significance of bacterial isolates in biodegradation of Benzene, Toluene, Ethyl benzene and o-Xylene (individually) were analysed. Seven different isolates were isolated from two different sources namely petroleum effluent and petroleum contaminated soil. After initial characterization of these isolates the growth pattern of them with BTEX as sole carbon source was carried out and the degradation potential were studied. The isolate Bacillus pumilus MVSV3 was identified and found to be effective degrader of BTEX. When 50 mg/L of BTEX was supplemented individually, Bacillus pumilus MVSV3 showed 56% of benzene, 59% of toluene, 55% of ethylbenzene and 54% of o-Xylene degradation. The bacterial isolate had potential to tolerate different metal ion concentration (0.5-0.25 mM) and varying percentage of salinity (2-10 %). The GCMS studies revealed that it could degrade BTEX into catechol and muconic acid, which are the major intermetabolites formed during an ortho pathway mediated degradation of monoaromatic hydrocarbons. These observations indicated that this strain has a good potential for degrading BTEX and could contribute significantly to biodegradation of monoaromatic compounds.

Keywords : BTEX; Bacillus pumilus; Logistic growth; Scanning Electron Microscope; HPLC, GCMS.