Bacterial community dynamics in an anaerobic plug-flow type bioreactor treating swine manure

• Published in: Water research (Oxford) Vol. 43; no. 1; pp. 21 - 32
• Main Authors: Roy, Caroline S., Talbot, Guylaine, Topp, Edward, Beaulieu, Carole, Palin, Marie-France, Massé, Daniel I.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 2009; Elsevier
• Subjects: Aerobiosis; Amplicon length heterogeneity PCR (LH-PCR); Anaerobic bioreactor; anaerobic digesters; Animals; Applied sciences; bacteria; Bacteria - metabolism; Bacterial community; Biodiversity; Bioreactors; Cluster Analysis; community structure; DNA, Ribosomal - genetics; equipment performance; Exact sciences and technology; Fatty Acids, Volatile - analysis; Manure; microbial genetics; Multivariate analysis; Other industrial wastes. Sewage sludge; Phylogeny; pig manure; Pollution; Polymerase Chain Reaction; ribosomal DNA; Ribosomal RNA; species diversity; Sus scrofa; Swine manure; Wastes; wastewater treatment; Water treatment and pollution; Anaerobic bioreactor; Multivariate analysis; Swine manure; Ribosomal RNA; Amplicon length heterogeneity PCR (LH-PCR); Bacterial community; Biological purification; LH-PCR; Anaerobe; Swine; Methanogenesis; Bacteria; Agricultural waste; Reactor; Ungulata; Community structure; Farmyard manure; Plug flow; Hydrolysis; Polymerase chain reaction; Amplicon length heterogeneity PCR; Vertebrata; Bioreactor; Mammalia; Acidogenesis; Surveillance; Artiodactyla; Animal waste
• ISSN: 0043-1354; 1879-2448
• DOI: 10.1016/j.watres.2008.09.034

A plug-flow type anaerobic reactor consisting of eight sequential compartments was used to study shifts in a bacterial community adapted to degrade swine manure at 25 °C. The investigation was carried out during the first 6 months of reactor operation. The reactor successfully separated the hydrolysis/acidogenesis stage from the methanogenesis stage. Bacterial 16S rDNA- and rRNA-based fingerprints obtained through amplicon length heterogeneity PCR (LH-PCR) were analyzed with a view to characterizing the bacterial community structure and the metabolically active community, respectively. Multivariate statistical tools showed that the rDNA-based fingerprints described a more temporal than compartmentalized distribution of similar bacterial communities. By contrast, the rRNA-based multivariate analyses described a distribution that was linked more to reactor performance parameters, especially during short time periods. Diversity indices calculated from fingerprint data were used to assess overall diversity shifts. The decrease in rRNA-based diversity observed through the reactor compartments was greater than the decrease in rDNA-based diversity. This finding indicates that the analysis of metabolically active bacteria diversity was more discriminative than the analysis based on the mere presence of bacteria. The observed decrease in diversity suggests that the bacterial community became specialized in degrading less diversified substrates through the compartments. All these findings suggest that rRNA-based analyses are more appropriate for monitoring reactor performance.