in this study, lactic acid production by repeated batch fermentation using cell entrapped methods was compared. barium alginate beads, agar gel and polyurethane foam cubes were employed as carriers to immobilize lactobacillus casei subsp. casei for the purpose of l (+)-lactic acid production. increasing concentrations of lactic acid during fermentation were better tolerated by barium alginate e...

In this study, lactic acid production by repeated batch fermentation using cell entrapped methods was compared. Barium alginate beads, agar gel and polyurethane foam cubes were employed as carriers to immobilize Lactobacillus casei subsp. casei for the purpose of L (+)-lactic acid production. Increasing concentrations of lactic acid during fermentation were better tolerated by barium alginate e...

Batch-to-batch iterative learning control of a fed-batch fermentation process using batchwise linearised models identified from process operation data is presented in this paper. Due to model-plant mismatches and the present of unknown disturbances, off-line calculated control policy may not be optimal when implemented to the real process. The repetitive nature of batch process allows informati...

The main aim of this work is the development of mathematical models of aerobic batch fermentations for its use in estimation and control algorithms. Most batch fermentation models are empirical and simple, and do not provide interrelationships between state variables and measurements. In this work such interrelationships are obtained from mass and energy balances of the fermentation components....

By applying a fed-batch strategy, production of Penicillium occitanis mannanases could be almost doubled as compared to a batch cultivation on acacia seeds (76 versus 41 U/mL). Also, a 10-fold increase of enzyme activities was observed from shake flask fermentation to the fed-batch fermentation. These production levels were 3-fold higher than those obtained on coconut meal. The high mannanase p...

Industrial fermentation systems are often operated in fed-batch mode [1], however this mode of operation can make planning and scheduling challenging due to batch-to-batch variation. There is natural variability in the length of the batch phase due to biological variations, in addition to batch-to-batch variations in initial process conditions from raw materials [2]. These affect the reproducib...

A mathematical model was developed to describe batch and continuous fermentation of glucose to organic acids with Clostridium tyrobutyricum. A modified Monod equation was used to describe cell growth, and a Luedeking-Piret equation was used to describe the production of butyric and acetic acids. Using the batch fermentation equations, models predicting butyric acid selectivity for continuous fe...

Fermentation of sugar by Saccharomyces cerevisiae, for production of ethanol in an immobilized cell reactor (ICR) was successfully carried out to improve the performance of the fermentation process. The fermentation set-up was comprised of a column packed with beads of immobilized cells. The immobilization of S. cerevisiae was simply performed by the enriched cells cultured media harvested at e...

Menaquinone-7 was produced by fermentation mainly using Bacillus subtilis species. Due to the low concentration of menaquinone-7 in fermentation processes and the associated expense of recovering the menaquinone-7, it was desirable to improve the fermentation concentration. The aim of this study was to determine the effect of fed-batch glycerol addition in the production of menaquinone-7 during...

Based on the widely accepted mathematical model of fermentation kinetics, an analytical solution is deduced in this paper. To describe the feature of batch fermentation, the parameters of the fermentation kinetics in the analytical solution (i.e., mumax, Ks, beta, YG, YP, and m) are estimated at one strike with POWELL optimization algorithm coded in FORTRAN-77. The experimental data in the exam...