An Alternative Approach for Oscillatory Behaviour Control in a Nonlinear Bioprocess

Oscillatory behaviour control in a continuous culture under double-substrate limitation

“…On the other hand, it should be mentioned that the growth of microorganisms in the presence of two sources of substrates is a quite complex process, as the available substrates can be utilized according to various consumption patterns. The presence of several limiting substrates can also affect the dynamical properties of continuous culture processes [9,10,17,25,36,52,53]. Egli [20] presented a thorough study of the possible consumption patterns in the presence of several available substrates.…”

“…Their results have shown that the change of carbon source (in their case galactose was replaced by glucose) prolonged the period of oscillations, but the case of using a mixture of these substrates was not investigated. The problem of using an additional substrate was also discussed in [52] for the classical chemostat model with variable yield coefficient and in [53] for the continuous fermentation process with a product inhibition model, where the mixture of two substrates was continuously fed into the reactor vessel. In both cases, the numerical results have shown that an appropriate proportion of both substrates in the mixture allowed for induction or elimination of the oscillatory behaviour.…”

“…In both cases, the numerical results have shown that an appropriate proportion of both substrates in the mixture allowed for induction or elimination of the oscillatory behaviour. However, the results presented in [52] were obtained based on the assumption that both substrates were utilized simultaneously, while in fermentation processes, a diauxic growth pattern is frequently observed as well [20]. In turn, the results presented in [53] were obtained assuming that the growth of microorganisms is inhibited by high product (ethanol) concentrations and only the diauxic growth pattern was taken into account.…”