Fed-batch cultivation of bakers' yeast: Effect of nutrient depletion and heat stress on cell composition

Ertugay N., Hamamci H., Bayindirli A.

FOLIA MICROBIOLOGICA, vol.42, no.3, pp.214-218, 1997 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 42 Issue: 3
  • Publication Date: 1997
  • Doi Number: 10.1007/bf02818981
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.214-218
  • Middle East Technical University Affiliated: Yes


The physiology of a commercial strain of bakers' yeast was studied in terms of the cell composition under different growth conditions and of its response to stress. The study comprised fed-batch experiments since this is the system used in bakers' yeast industry. The classical fed-batch fermentation procedure was modified in that the yeast cells were continuously grown to a steady-state at a dilution rate of 0.1/h in order to achieve more or less the same initial starting point in terms of cell composition. This steady-state culture was then switched to fed-batch concomitantly with exposure to stress. The highest amount of trehalose accumulation was achieved when nutrient depletion and heat stress were applied concomitantly. The highest amount of trehalose, 12 %, was attained in cells stressed by both nitrogen depletion and heat stress. The protein content remained constant, although with some oscillations, at a value of 30 % throughout this dual stress experiment.