Archives of Microbiology

, Volume 107, Issue 1, pp 41–47

A method for the regulation of microbial population density during continuous culture at high growth rates

  • Glenn A. Martin
  • Walter P. Hempfling

DOI: 10.1007/BF00427865

Cite this article as:
Martin, G.A. & Hempfling, W.P. Arch. Microbiol. (1976) 107: 41. doi:10.1007/BF00427865


A method for the continuous culture of microorganisms is described which employs growth-dependent pH changes to control the rate of addition of fresh medium to a culture vessel. The apparatus (the “phauxostat”) supports, at constant pH, longterm continuous culture at rates near or at the maximum of which the organisms are capable. The buffering capacity of the inflowing medium determines the steady-state population density of the culture, but the rate of growth is independent of the buffering capacity. The fundamental theory of operation is tested and some basic parameters of growth are estimated using Escherichia coli B growing continuously in media containing glucose, glycerol or DL-lactate.

Key words

Escherichia coli BContinuous culture“Phauxostat”Growth rate

Copyright information

© Springer-Verlag 1976

Authors and Affiliations

  • Glenn A. Martin
    • 1
  • Walter P. Hempfling
    • 1
  1. 1.Department of BiologyUniversity of Rochester, River StationRochesterUSA