Aerobic biodegradation of benzene, toluene and ethylbenzene in liquid medium by a bacterial consortium, isolated from non-history clay soil, and their interrelation effect

摘要

The present study was carried out in order to investigate the ability of isolated subsurface bacteria, from a non-history clay soil, to biodegrade the non-aqueous phase-liquids (NAPLs), monoaromatic hydrocarbons: benzene, toluene and ethylbenzene. First stage of the study was focussed on stand-alone biodegradation of each contaminant under described conditions. Benzene (100, 260 and 500 mg/l) exposed to isolated soil bacteria for 14 days, was biodegraded 100, 70 and 50%, respectively, ethylbenzene (100, 260 and 500 mg/l) at 85, 87 and 90%, respectively and toluene (100, 260 and 500 mg/l) revealed the lowest rate of 45, 50 and 52%. Toluene and ethylbenzene showed a direct increase in biodegradation associated with increase in their concentration. The second stage was the biodegradation of benzene, toluene and ethylbenzene admixture tall three compounds at the very same concentrations, wlv) in glucose absence and supplemented with Tween 80 (10 and 15 mg/l). The overall biodegradation improved when contaminants were mixed together. [References: 12]