Production of D-galacturonic acid from agricultural residues with Aspergillus niger in a stirred-tank reactor

**Production of D-galacturonic acid from agricultural residues with Aspergillus niger in a stirred-tank reactor**

Dominik Schäfer, doctoral thesis Technical University of Munich, 2022

The pectinolytic activities of different Aspergillus niger strains were characterized in controlled stirred-tank bioreactors in a comparative study. Suitable reaction conditions for hydrolysis of pectin-rich extracted sugar beet press pulp were identified using the enzyme mix produced by Aspergillus niger. A subsequent process integration of enzyme production with Aspergillus niger and hydrolysis of extracted sugar beet press pulp in a stirred-tank bioreactor enabled efficient production of D-galacturonic acid.

Publications

Knesebeck M, Schäfer D, Schmitz K, Rüllke M, Benz JP, Weuster-Botz D (2023): Enzymatic one-pot hydrolysis of extracted sugar beet press pulp after solid-state fermentation with an engineered Aspergillus niger strain. Fermentation 9: 582.
Wagner J, Schäfer D, von den Eichen N, Haimerl C, Harth S, Oreb M, Benz JP, Weuster-Botz D (2021): D-galacturonic acid reduction by S. cerevisiae for L-galactonate production from extracted sugar beet press pulp hydrolysate. Appl Microbiol Biotechnol 105: 5795–5807.
Schäfer D, Schmitz K, Weuster-Botz D, Benz JP (2020): Comparative evaluation of Aspergillus niger strains for endogenous pectin depolymerization capacity and suitability for D-galacturonic acid production. Bioproc Biosys Eng 43: 1549–1560.