In this work, kinetic analysis of the fermentation process controlled
by constant temperatures showed that relatively high
temperature at the earlier stage of fermentation was advantageous
for cell growth and glucose consumption (cell growth stage).
However, amoderate low temperature could enhance the ARA production
(ARA producing stage). This phenomenon indicated that
the suitable temperatures for cell growth and ARA accumulation
were different, and the single temperature control experiments
could only accommodate one set of conditions suitable for either
cell growth or product formation. Itwasbeneficial to control culture
temperature in ARA fermentation, then a two stage temperatureshift
strategy was proposed in this work.
This study demonstrated that ARA production could be considerably
improved by using the proposed temperature-shift
strategy. It was particularly attractive for large scale ARA fermentation
because temperature was a convenient control variable
and easily manipulated. This was another example showing the
advantage of two-stage control strategy in terms of microbial
physiology