Agitation effects on submerged growth and product formation of Aspergillus niger

• Published in: Bioprocess and biosystems engineering Vol. 26; no. 5; pp. 315 - 323
• Main Authors: Kelly, Sven, Grimm, Luis H, Hengstler, Jan, Schultheis, Ellen, Krull, Rainer, Hempel, Dietmar C
• Format: Journal Article
• Language: English
• Published: Germany Springer Nature B.V 01.10.2004
• Subjects: Aspergillus niger; Aspergillus niger - cytology; Aspergillus niger - physiology; Bioreactors; Bioreactors - microbiology; Cell Culture Techniques - methods; Cell Proliferation; Computer Simulation; Energy dissipation; Fungal Proteins - biosynthesis; Glucose - metabolism; Mechanotransduction, Cellular - physiology; Microfluidics - methods; Models, Biological; Motion; Physical Stimulation - methods
• ISSN: 1615-7591; 1615-7605
• DOI: 10.1007/s00449-004-0368-y

Product formation of mycelial organisms, like Aspergillus niger, is intimately connected with their morphology. Pellet morphology is often requested for product formation. Therefore, it is important to reveal the influence of the hydrodynamic conditions on the morphological development. In the present study, pellet morphology and glucoamylase formation were studied under different agitation intensities of A. niger AB1.13. For pellet formation inside the bioreactor, without the use of precultures, it is necessary to work at low energy dissipation rates. Biomass growth and glucoamylase activity were correlated with energy dissipation. Furthermore, product yield was analysed in dependence of pellet size and concentration. The present work shows that simple equations based on Monod-kinetics can describe growth and product formation, in general, also in mycelian organisms. All measured morphological data, like pellet concentration, as well as glucoamylase formation, strongly depend on the hydrodynamic conditions.