Study of the diversity of microbial communities in a sequencing batch reactor oxic-settling-anaerobic process and its modified process

Can J Microbiol. 2016 May;62(5):411-21. doi: 10.1139/cjm-2015-0194. Epub 2016 Jan 19.

Abstract

To further reveal the mechanism of sludge reduction in the oxic-settling-anaerobic (OSA) process, the polymerase chain reaction - denaturing gradient gel electrophoresis protocol was used to study the possible difference in the microbial communities between a sequencing batch reactor (SBR)-OSA process and its modified process, by analyzing the change in the diversity of the microbial communities in each reactor of both systems. The results indicated that the structure of the microbial communities in aerobic reactors of the 2 processes was very different, but the predominant microbial populations in anaerobic reactors were similar. The predominant microbial population in the aerobic reactor of the SBR-OSA belonged to Burkholderia cepacia, class Betaproteobacteria, while those of the modified process belonged to the classes Alphaproteobacteria, Betaproteobacteria, and Gammaproteobacteria. These 3 types of microbes had a cryptic growth characteristic, which was the main cause of a greater sludge reduction efficiency achieved by the modified process.

Keywords: croissance cryptique; cryptic growth; diversity of microbial communities; diversité des communautés microbiennes; réduction des boues; sludge reduction; traitement des eaux usées; wastewater treatment.

MeSH terms

  • Anaerobiosis
  • Betaproteobacteria / isolation & purification
  • Bioreactors / microbiology*
  • Denaturing Gradient Gel Electrophoresis
  • Polymerase Chain Reaction
  • Sewage / microbiology*
  • Waste Disposal, Fluid / methods

Substances

  • Sewage