Bioproduction of succinic acid from potato waste. Kinetic modeling

Abstract

Succinic acid is a key chemical platform for the implementation of biorefineries and, therefore, for the development of a sustainable bioeconomy. In this work, succinic acid anaerobic production by Actinobacillus succinogenes from potato waste and glucose was carried out. Firstly, a simple kinetic model was developed to accurately predict the evolution of succinic acid, substrate, by-products, and biomass based on bottle experiments performed at different initial glucose concentrations. Secondly, experiments with an acid hydrolysate of potato waste as carbon source were performed in orbitally shaken bottles and bioreactor to compare the fermentation performance of the potato waste with the pure glucose. Using this hydrolysate, 32.2 g‧L-1 of succinic acid were obtained with a productivity of 0.64 g‧L-1‧h-1, improving SA yield by 37% compared to results with pure glucose. This is one of the highest values to date for succinic acid bioproduction from food residues (0.92 g‧ g-1). Finally, the proposed kinetic model was successfully applied to the fermentation data obtained from potato waste fermentation, being this type of models a highly valuable tool for future techno-economic analysis of the bioprocess.