A comparative study of eubacterial communities by PCR-DGGE fingerprints in anoxic and aerobic biotrickling filters used for biogas desulfurization

Biological desulfurization has proven to be a process that is technically and economically feasible on using biotrickling filters that can be performed under aerobic and anoxic conditions. However, microbial communities are different mainly due to the use of different final electron acceptors. The analysis of microbial communities in these systems has not been addressed with regard to the anoxic process. The aim of the work reported here was to analyse the eubacterial community in the two types of bioreactor along the packed bed and during the operation time. The analysis was carried out using the 16S PCR-DGGE molecular fingerprint technique. The microbial profile analysis in the aerobic bioreactor revealed that the community was more diverse and stratified compared to those obtained in the two anoxic bioreactors, influenced by environmental factors. The main OTU involved in this process is genus Thiobacillus, although different species were detected depending on each operational condition.