Heterologous Flocculation of Escherichia Coli and Yeast

  • R. G. Protheroe
  • R. H. Cumming
  • A. J. Matchett


Mixed cell suspensions of Escherichia coli and Saccharomyces sp. spontaneously flocculated to an extent dependent upon environmental ionic strength. When separately suspended, the bacteria or yeast maintained theirmono dispersity over the range of ionic strengths in vestigated Maximal expression offlocculation was observed at an ionic strength of 0.0 15 sodium chloride and above.At ionic strengths of zero and 0.0015, mixed cell populations did not flocculate.Eventual floesize distribution swere a function of the initial concentrations of each species.Flocculation persisted irrespective of the presence of nutrient broth growth medium.


Ionic Strength Floc Size Cell Size Distribution Mixed Suspension Floc Formation 
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.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    .Wang, D.I.C., Separation for Biotechology. In Separations for Biotechnology, ed. M.S. Verall and M.J. Hudson, Ellis Horwood, 1987, pp30–48.Google Scholar
  2. 2.
    .Vincent, B., The Effect of Adsorbed polymers on dispersion stability. Advances in Colloid and Interface Science, 1974, 4, 193–277.CrossRefGoogle Scholar
  3. 3.
    .Verway, E.J.W., and Overbeek, J.Th.G, Theory of stability of lyophobic colloids. Elsevier, Amsterdam, 1948.Google Scholar
  4. 4.
    .Shaw, D.J., in Introduction to Colloid and Surface Chemistry. Butter worths, London, 1980.Google Scholar
  5. 5.
    .Visser, J., Adhesion of colloidal particles. Surface and Colloid Science, 1976, 8, pp3–84.Google Scholar
  6. 6.
    James., The electrical properties and Topochemistry of Bacterial Cells. Adv Colloid Interface Science, 1982, 15, pp171–221.Google Scholar
  7. 7.
    .Vrij, A., Polymers at interfaces and the interactions in colloidal dispersions. Pure and applied chemistry, 1976, 48, 471–483.CrossRefGoogle Scholar
  8. 8.
    Vincent, B., Young, C.A. and Tadros, Th, F.T., Equilibrium aspects of heterologous flocculation in mixed sterically stabilised dispersions. Faraday Discussions of the Chemical Society,Google Scholar

Copyright information

© SCI 1990

Authors and Affiliations

  • R. G. Protheroe
    • 1
  • R. H. Cumming
    • 1
  • A. J. Matchett
    • 1
  1. 1.North East Biotechnology Centre, Department of Chemical EngineeringTeesside PolytechnicMiddlesbrough, ClevelandEngland

Personalised recommendations