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Isolation of alkali‐tolerant benzene‐degrading bacteria from a contaminated aquifer
Author(s) -
Fahy A.,
Ball A.S.,
Lethbridge G.,
Timmis K.N.,
McGenity T.J.
Publication year - 2008
Publication title -
letters in applied microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.698
H-Index - 110
eISSN - 1472-765X
pISSN - 0266-8254
DOI - 10.1111/j.1472-765x.2008.02386.x
Subject(s) - benzene , btex , ethylbenzene , environmental chemistry , chemistry , toluene , microbacterium , bioremediation , rhodococcus , cometabolism , biodegradation , bacteria , pseudomonas , microbiology and biotechnology , organic chemistry , biology , enzyme , genetics
Aims: To isolate benzene‐degrading strains from neutral and alkaline groundwaters contaminated by benzene, toluene, ethylbenzene, xylenes (BTEX) from the SIReN aquifer, UK, and to test their effective pH range and ability to degrade TEX. Methods and Results: The 14 isolates studied had an optimum pH for growth of 8, and could degrade benzene to below detection level (1 μ g l −1 ). Five Rhodococcus erythropolis strains were able to metabolize benzene up to pH 9, two distinct R. erythropolis strains to pH 10, and one Arthrobacter strain to pH 8·5. These Actinobacteria also degraded benzene at least down to pH 5·5. Six other isolates, a Hydrogenophaga and five Pseudomonas strains, had a narrower pH tolerance for benzene degradation (pH 6 to 8·5), and could metabolize toluene; in addition, the Hydrogenophaga and two Pseudomonas strains utilized o‐ , m‐ or p‐ xylenes. None of these strains degraded ethylbenzene. Conclusions: Phylogenetically distinct isolates, able to degrade BTX compounds, were obtained, and some degraded benzene at high pH. Significance and Impact of the Study: High pH has previously been found to inhibit in situ degradation of benzene, a widespread, carcinogenic groundwater contaminant. These benzene‐degrading organisms therefore have potential applications in the remediation or natural attenuation of alkaline waters.