Mathematical Modelling and Scale-up of Batch Fermentation with Burkholderia cepacia B27 Using Vegetal Oil as Carbon Source to Produce Polyhydroxyalkanoates

Abstract

A mathematical model that predicts biomass growth and polyhidroxyalkanoates (PHAs) accumulation in Burkholderia cepacia B27 and its validation at pilot plant scale is presented in this work. During the fermentation process, the mutated strain was capable to produce 15 g/L of PHA and accumulate 86 % of bacteria weight as polymer, with corn oil as carbon source. Bioreactor assays were performed with a 5 L working volume, pH 7.0 and 32 °C. The model development steps were the following: 1) kinetic behavior analysis; 2) formulation of differential equations to predict kinetic behavior; 3) fitting of model parameters with Matlab® solvers, and 4) model validation with statistical and experimental tests. The experimental validation was developed under batch conditions with a work volume of 60 L, showing a good prediction of the system behavior. This model will be useful for the optimization of the feed-batch process that is the next step in the research.