Effect of carbon to nitrogen ratio on the composition of microbial extracellular polymers in activated sludge

Durmaz B., Sanin F.

WATER SCIENCE AND TECHNOLOGY, vol.44, pp.221-229, 2001 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 44
  • Publication Date: 2001
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.221-229
  • Keywords: activated sludge, carbohydrates, C/N ratio, extracellular polymers, proteins, EXTRACTION, BACTERIA, BIOFLOCCULATION, POLYSACCHARIDE, AGGREGATION, PROTEIN
  • Middle East Technical University Affiliated: Yes


Effect of carbon to nitrogen ratio (C/N) on the sludge extracellular polymer composition is studied in synthetically fed semi-continuous reactors with 8 days of sludge age. Results show that C/N ratio influences the relative distribution of polymer carbohydrate and protein. At low C/N ratio of 5, polymer extracts have high protein and low carbohydrate content. As the C/N ratio is increased to 17.5 and then to 40, carbohydrate concentration increases sharply and protein concentration decreases.