Applied Microbiology and Biotechnology

, Volume 77, Issue 3, pp 605–612

Enzyme activities in activated sludge flocs

  • Guang-Hui Yu
  • Pin-Jing He
  • Li-Ming Shao
  • Duu-Jong Lee
Biotechnologically Relevant Enzymes and Proteins

DOI: 10.1007/s00253-007-1204-5

Cite this article as:
Yu, GH., He, PJ., Shao, LM. et al. Appl Microbiol Biotechnol (2007) 77: 605. doi:10.1007/s00253-007-1204-5

Abstract

This study quantified the activities of enzymes in extracellular polymeric substances (EPS) and in pellets. Seven commonly adopted extraction schemes were utilized to extract from aerobic flocs the contained EPS, which were further categorized into loosely bound (LB) and tightly bound (TB) fractions. Ultrasonication effectively extracted the EPS from sludge flocs. Enzyme assay tests showed that the protease activity was localized mainly on the pellets, α-amylase and α-glucosidase activities were largely bound with LB-EPS, and few protease, α-amylase, or α-glucosidase activities were associated with the TB-EPS fraction. There exists no correlation between the biochemical compositions of EPS and the distribution of enzyme activities in the sludge matrix. The 44–65% of α-amylase and 59–100% of α-glucosidase activities noted with the LB-EPS indicate heterogeneous hydrolysis patterns in the sludge flocs with proteins and carbohydrates.

Keywords

Enzymatic distribution Enzymes Extracellular polymeric substances Extraction process Infrared spectra Sludge 

Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  • Guang-Hui Yu
    • 1
  • Pin-Jing He
    • 1
  • Li-Ming Shao
    • 1
  • Duu-Jong Lee
    • 2
  1. 1.State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze River Water Environment, College of Environmental Science and EngineeringTongji UniversityShanghaiPeople’s Republic of China
  2. 2.Department of Chemical EngineeringNational Taiwan UniversityTaipeiTaiwan