Comparison of microbial community composition and activity in sulfate‐reducing batch systems remediating mine drainage

Abstract

Five microbial inocula were evaluated in batch tests for the ability to remediate mine drainage (MD). Dairy manure (DM), anaerobic digester sludge, substrate from the Luttrell (LUTR) and Peerless Jenny King (PJK) sulfate-reducing permeable reactive zones (SR-PRZs) and material from an MD-treatment column that had been inoculated with material from a previous MD-treatment column were compared in terms of sulfate and metal removal and pH neutralization. The microbial communities were characterized at 0, 2, 4, 9, and 14 weeks using denaturing gradient gel electrophoresis and quantitative polymerase chain reaction to quantify all bacteria and the sulfate-reducing bacteria of the genus Desulfovibrio. The cultures inoculated with the LUTR, PJK, and DM materials demonstrated significantly higher rates of sulfate and metal removal, and contained all the microorganisms associated with the desired functions of SR-PRZs (i.e., polysaccharide degradation, fermentation, and sulfate reduction) as well as a relatively high proportion of Desulfovibrio spp. These results demonstrate that inoculum influences performance and also provide insights into key aspects of inoculum composition that impact performance. This is the first systematic biomolecular examination of the relationship between microbial community composition and MD remediation capabilities.

Effect of COD:SO4 2− Ratio, HRT and Linoleic Acid Concentration on Mesophilic Sulfate Reduction: Reactor Performance and Microbial Population Dynamics

“…The presence of Clostridium sp. and species belonging to Bacteroidetes is consistent with the findings from other studies, where these species were observed under SO4 2− reducing conditions and capable of producing a mixture of VFAs from solid organic substrates and sugar beet molasses [39,40]. In the current study, acetate, propionate and formate which constituted approximately 30% to 40% of the initial COD fed to the reactors were observed in cultures fed 0.5 g·L…”

Detection and Quantification of Functional Genes of Cellulose- Degrading, Fermentative, and Sulfate-Reducing Bacteria and Methanogenic Archaea

“…This observation is supported by several other 16S rRNA gene surveys of similar systems (26,29,36,38). This indicates that for every 100 clones screened, only 2 are likely to represent sulfate reducers.…”

“…In addition, methanogens can also utilize some of the fermentation products. In many cases, functionally important members, such as SRB, are present only as a small fraction of the community (36,38), making them difficult to detect by use of 16S rRNA gene-targeted fingerprinting methods. Furthermore, the phylogenetic diversity of cellulose degraders, fermenters, and SRB prevents their quantification using a small number of 16S rRNA gene-targeted probes.…”

Decline in Performance of Biochemical Reactors for Sulphate Removal from Mine-Influenced Water is Accompanied by Changes in Organic Matter Characteristics and Microbial Population Composition

“…Previous studies used molecular methods to identify sulphate-reducing and organic matter degrading taxonomic groups in BCRs [22,43]. These previous methods were insufficient to capture the diversity of microbial species expected in anaerobic, organic-rich biomes.…”