Mathematical modeling of the biotechnological production of xylitol from hydrolysates of agro-industrial waste

Abstract

Xylitol is widely used in the pharmaceutical and food industries since it has cariogenic properties and low caloric value compared to sucrose. In recent decades, its demand has increased, which has motivated the generation of alternatives for its production. The biotechnological route is an attractive alternative since in addition to reducing production costs, it uses lignocellulosic hydrolysates from agro-industrial residues as raw material. However, due to the inherent variability in the composition of the waste, the implementation of the process is not a simple task, i. e., the determination of the operating conditions that maximize production yield requires a broad experimental design. In this sense, mathematical modeling can help reduce experimental work, and allows for predicting and evaluating the dynamic behavior of key variables, making it a useful tool for the implementation of process optimization and control schemes. Therefore, the objective of this work is to propose a generalized mathematical model that can be adapted to different study cases (i.e., different substrates and microorganism strains), operating conditions, and fermenter configuration. The results show high determination coefficients R2 > 0.90 for each case study, indicating that the proposed model is easily adaptable to different substrates and operating conditions. In addition, the model allows the incorporation of different effects such as pH, temperature, and agitation.