Applied Microbiology and Biotechnology

, Volume 65, Issue 2, pp 143–148 | Cite as

The effects of extracellular polymeric substances on the formation and stability of biogranules

  • Yong-Qiang Liu
  • Yu LiuEmail author
  • Joo-Hwa Tay


Biogranulation is a promising biotechnology developed for wastewater treatment. Biogranules exhibit a matrix microbial structure, and intensive research has shown that extracellular polymeric substances (EPS) are a major component of the biogranule matrix material in both anaerobic and aerobic granules. This paper aims to review the role of EPS in biogranulation, factors influencing EPS production, the effect of EPS on cell surface properties of biogranules, and the relationship of EPS to the structural stability of biogranules. EPS production is substantially enhanced when the microbial community is subject to stressful culture conditions, and the stimulated EPS production in the microbial matrix in turn favours the formation of anaerobic and aerobic granules. EPS can also play an essential role in maintaining the integrity and stability of spatial structure in mature biogranules. It is expected that this paper can provide deep insights into the functions of EPS in the biogranulation process.


Extracellular Polymeric Substance Sequencing Batch Reactor Granular Sludge Extracellular Polysaccharide Upflow Anaerobic Sludge Blanket 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag 2004

Authors and Affiliations

  1. 1.Division of Environmental and Water Resources Engineering, School of Civil and Environmental EngineeringNanyang Technological UniversitySingapore

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