摘要: |
Pinkwater, a hazardous wastewater containing 2,4,6-trinitrotoluene (TNT), is produced during munition production or demilitarization operations. Anaerobic bioreactors are under investigation as an alternative to activated carbon for treating pinkwater. This research studied the microbial community structure of an anaerobic bioreactor treating a synthetic feed containing ethanol and TNT. Samples from the reactor were taken weekly, ribonucleic acid (RNA) was extracted and membrane hybridizations were performed using ologonucleotide probes specific for the domains Bacteria and Archaea. The bacterial and archaeal ribosomal RNA (rRNA) were similar between the two reactors, but, after doubling the TNT loading, the archaeal rRNA decreased and the bacterial rRNA increased. In response to the increased TNT loading, the alpha-Proteobacteria increased to 60 percent of the bacterial rRNA, but remained unchanged in the control reactor. In the control reactor, the Methanosarcinales accounted for about 80 percent of the archaeal rRNA, while, in the +TNT reactor, they decreased from about 50 percent to 20 percent after increasing the TNT loading. The Methanomicrobiales accounted for about 80 percent of the Archaea, while they were barely detectable in the control reactor. The findings indicate that TNT significantly affects the bacterial and archaeal community structure. Several strategies are suggested for assessing and optimizing anaerobic bioreactors treating pinkwater. |