Modeling the kinetics of cell growth and ganoderic acid production in liquid static cultures of the medicinal mushroom Ganoderma lucidum

Abstract

The kinetics of cell growth and ganoderic acid (GA) production by liquid static culture of the medicinal mushroom Ganoderma lucidum in bioreactors was investigated. A simple unstructured kinetic model could describe this novel static culture process. Parameters in the model were determined by fitting the model with experimental data. The model well described the dynamics of cell growth, lactose consumption and GA accumulation by G. lucidum cells. Parameter sensitivity analysis indicated that the model was sensitive to changes in maximum specific growth rate ( μ m), the saturation constant ( K s), the biomass yield against lactose ( Y X / S ) and the growth-associated product formation constant ( α). The model was able to predict the static culture process of G. lucidum in various laboratory-scale multi-layer static bioreactors with working volumes from 20 mL to 7.5 L. Because there is a great need for efficient large-scale production of GA, a very useful antitumor metabolite, by the mushroom cultivation, the model identified might be useful in converting large-scale static culture processes to industrial application.