Growth kinetic parameters and biosynthesis of polyhydroxybutyrate in Cupriavidus necator DSMZ 545 on selected substrates

Abstract

Kinetic model for Cupriavidus necator in batch culture using glucose, fructose and molasses as carbon sources was obtained. The experimental data was also fitted with the modified logistic equation that can provide adequate description for PHB synthesized by C. necator. The lineweaver-Burk plot defined biokinetic coefficients which were described by a simplified Monod?s rate model. The specific growth rates, ?max and the Monod constants, Ks, for various substrates such as glucose, fructose and molasses were 0.18, 1.25, 0.42 h-1 and 107.53, 30.342, 188.16 g/l, respectively. The kinetic constants were evaluated on the basis of non-linear regression were solved using MATLAB software. A good agreement was found between the experimental and the predicted values, which indicated that the model with differential equations would describe fermentation process for the PHB formation.