BIOPRODUCTION OF PROPIONIC ACID USING RENEWABLE SUBSTRATES

This work explores the production of propionic acid (PA) via microbial fermentation using Acidipropionibacterium acidipropionici DSM 4900 and renewable substrates (xylose and glycerol). Shake flask and bioreactor experiments were conducted with different substrate ratios to optimize process productivity and efficiency. The most promising condition was a fed-batch with glycerol, reaching a total PA concentration of 24.5 g/L, productivity of 0.18 g/L·h, yield of 0.57 g/g, and bioconversion efficiency of 71%. The use of low-cost, renewable carbon sources highlights the potential of the process for sustainable biorefinery applications, aligned with the circular economy principles.