title: Industrial glucoamylase fed-batch benefits from oxygen limitation and high osmolarity.
abstract: The market for glucoamylase is large and very competitive and the production process has been optimized through several decades. So far a thorough characterization of the process has not been published, but previous academic reports suggest that the process suffers from severe byproduct formation. In this study we have carried out a thorough characterization of a process as close as possible to the industrial reality. The results show that the oxygen-limited phases of the process have the highest glucoamylase yields on carbon and that the byproducts are efficiently reused in late phases of the process. An alternative process with low glucose concentration show that high osmolarity is beneficial for the process, and we conclude that oxygen limitation, high osmolarity, and the associated byproduct metabolism are important for the efficiency of the process.
authors.affiliation: Center for Microbial Biotechnology, Department of Systems Biology, Technical University of Denmark, Søltofts Plads, Building 223, DK-2800 Kgs Lyngby, Denmark.
authors.forename: Lasse
authors.initials: L
authors.lastname: Pedersen
authors.forename: Kim
authors.initials: K
authors.lastname: Hansen
authors.forename: Jens
authors.initials: J
authors.lastname: Nielsen
authors.forename: Anna Eliasson
authors.initials: AE
authors.lastname: Lantz
authors.forename: Jette
authors.initials: J
authors.lastname: Thykaer
mesh_terms: D001234:Aspergillus niger / Q000201:enzymology* / Q000378:metabolism; D002244:Carbon / Q000378:metabolism; D003470:Culture Media / Q000737:chemistry*; D005285:Fermentation; D005087:Glucan 1,4-alpha-Glucosidase / Q000096:biosynthesis*; D005947:Glucose / Q000378:metabolism; D009994:Osmolar Concentration; D010100:Oxygen / Q000378:metabolism*
chemical_list: D003470:Culture Media; D002244:Carbon; D005087:Glucan 1,4-alpha-Glucosidase; D005947:Glucose; D010100:Oxygen