1749-1757 JMB12-06015.fm

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 R 2 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 LeudekingPiret 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.