An extensive investigation was carried out to describe the
kinetics of cell growth, substrate consumption, and
product formation in the batch fermentation using starch
as substrate. Evaluation of intrinsic kinetic parameters
was carried out using a best-fit unstructured model. A
nonlinear regression technique was applied for computational
purpose. The Andrew’s model showed a comparatively
better R2 value among all tested models. The values of
specific growth rate (μmax), saturation constant (KS),
inhibition constant (KI), and YX/S were found to be 0.109 h-1,
11.1 g/l, 0.012 g/l, and 1.003, respectively. The Leudeking-
Piret model was used to study the product formation
kinetics and the process was found to be growth-associated.
The growth-associated constant (α) for protease production
was sensitive to substrate concentration. Its value was
fairly constant up to a substrate concentration of 30.8 g/l,
and then decreased.

Keywords: Cell growth, Fermentation, Kinetics, Modeling, Simulation