Basics of the black box model
Technology for Biobased Products
Sef Heijnen, Department of Biotechnology, Faculty of Applied Sciences
Process reac on for 1 mol PDO
qNH
+ qO qCO qH O qH + qQ
qs µ +
+
42 2 2
*C6 H12O6 + * NH4 + *O2 + *C1H1.8O0.5N0.2 +1*C3H8O2 + *CO2 + * H2O + * H + (heat)
qp qp qp qp qp qp
qp qp
Biomass PDO
q rate values are needed
What determines q rates?
cvitamins
Temperature
cNH4
pH
cCO2
ctrace metals
cs Pressure
cO2
, cO2, cCO2, cNH4, cvitamins, ctrace metals, etc...
)
cs
qi = func on of (
T, P, pH,
Very complicated kine cs func on for qi
Trick: single nutrient limi ng nutrient medium
cvitamins
cNH4
cCO2
ctrace metals
Limiting concentration
cs
cO2
, cO2, cCO2, cNH4, cvitamins, ctrace metals, etc...
cs
qi = func on of ( )
qi only depends on cs (at constant pH, T and pressure)
Intracellular pseudo steady state: Flux coupling
Product qp(cs)
Substrate
Biomass ź(cs)
Black Box
CO2 qCO2(cs)
qi(cs) (i = O2, H2O, etc)
" Short passage me (<1 minute)
" Low intracellular metabolite concentra on (10 2  10 6 M)
See you in the next unit!