RELEASE OF INTRACELLULAR β-GALACTOSIDASE FROMLACTOBACILLUS ACIDOPHILUSAND L-ASPARAGINASE FROMPECTOBACTERIUM CAROTOVORUMBY HIGH-PRESSURE HOMOGENIZATION

Operator training simulation for integrating cultivation and homogenisation in protein production

“…Furthermore, we observed decreased flow rates at higher pressure as also noted by Choonia et al [6] . Thus, a linear equation is used to describe the change of the flow rate ( F ) at different pressure ( P ): Applied model parameters are defined from own data where 45.0 L/h is the maximum flow rate without homogenisation pressure.…”

“…, Refs. [14] , [23] , [6] ) where the release of protein increases with pressure, our second simulation at 30 MPa shows less release than the data from the experimental run ( Fig. 2b ).…”

“…To train Need 3, four microorganisms of different sensitivity to cell disruption were included in the simulations. The constraints used in these simulations were based on studies showing how protein release and cell disruption depend on temperature, pressure and number of passes in the homogeniser [23] , [19] , [6] . In particular the dependence of the type of microorganism and suspension temperature was applied where the parameter K , K d and a were described as function of suspension temperature using a sigmoidal function (Supplementary data, Eqs.…”

“…It is related to the cell wall structure but might also be influenced by growth conditions, growth rate, cell concentration and the temperature of the suspension as suggested in other reports [11] , [8] , [19] . Subsequent development of this model has been done by Augenstein et al; Sauer et al; Spiden et al [1] , [24] , [19] , and Choonia et al [6] .…”

“…(7) for the specific denaturation rate they predicted the total protein yield. Moreover, Choonia et al [6] added observations of decrease of protein concentration at higher pressure and Engler and Campell [8] did observations on disruption stress effects.…”