Year: 2026 | Month: October | Volume: 13 | Issue: 10 | Pages: 356-369
DOI: https://doi.org/10.52403/ijrr.20261032
Isolation and Screening of BTEX (Benzene, Toluene, Ethylbenzene, and Xylene)-Degrading Bacteria from Petroleum-Contaminated Soil
Pradnya Ingale1, Lolly Jain1
1Dept. of Microbiology, K. J. Somaiyaa College of Science and Commerce, Vidya Vihar East, Mumbai-40007, Maharashtra (India)
Corresponding Author: Lolly Jain
ABSTRACT
Benzene, toluene, ethylbenzene, and xylene (BTEX) are toxic monoaromatic hydrocarbons frequently detected in petroleum-contaminated environments. Microbial biodegradation is an environmentally sustainable strategy for removing these pollutants. The present study aimed to isolate and screen indigenous BTEX-degrading bacteria from petroleum-contaminated soil samples. We used enrichment culture techniques with mineral salt medium (MSM) supplemented with BTEX as the sole carbon source. We supplied each BTEX compound at 300 ppm to evaluate microbial degradation efficiency. After enrichment and plating, we obtained 96 bacterial isolates, of which 16 showed substantial growth in BTEX-containing MSM. We selected three fast-growing isolates, designated P, D, and F, for further biodegradation analysis. Degradation experiments were conducted for 8 days, and residual BTEX concentrations were analyzed using GC-FID. All three isolates demonstrated measurable degradation, with isolate D exhibiting the highest efficiency among individual strains. Comparison with a reference strain (Pseudomonas MTCC 102) revealed compound-specific degradation behaviour, while the developed microbial consortium showed the highest overall degradation efficiency, as evidenced by higher percentage degradation and a reduced total peak area. 16S rRNA gene sequencing identified the isolates as Acinetobacter schindleri, Pseudomonas aeruginosa, and Pseudomonas taiwanensis. These findings highlight the superiority of microbial consortia over individual strains and demonstrate their potential for bioremediation of BTEX-contaminated environments.
Keywords: BTEX; isolation; screening; biodegradation; petroleum-contaminated soil; gas chromatography
[PDF Full Text]