title: Evaluation of the energy efficiency of enzyme fermentation by mechanistic modeling.
abstract: Modeling biotechnological processes is key to obtaining increased productivity and efficiency. Particularly crucial to successful modeling of such systems is the coupling of the physical transport phenomena and the biological activity in one model. We have applied a model for the expression of cellulosic enzymes by the filamentous fungus Trichoderma reesei and found excellent agreement with experimental data. The most influential factor was demonstrated to be viscosity and its influence on mass transfer. Not surprisingly, the biological model is also shown to have high influence on the model prediction. At different rates of agitation and aeration as well as headspace pressure, we can predict the energy efficiency of oxygen transfer, a key process parameter for economical production of industrial enzymes. An inverse relationship between the productivity and energy efficiency of the process was found. This modeling approach can be used by manufacturers to evaluate the enzyme fermentation process for a range of different process conditions with regard to energy efficiency.
authors.affiliation: Department of Chemical and Biochemical Engineering, Technical University of Denmark, Building 229, DK-2800 Kgs. Lyngby, Denmark.
authors.forename: Mads O
authors.initials: MO
authors.lastname: Albaek
authors.forename: Krist V
authors.initials: KV
authors.lastname: Gernaey
authors.forename: Morten S
authors.initials: MS
authors.lastname: Hansen
authors.forename: Stuart M
authors.initials: SM
authors.lastname: Stocks
mesh_terms: D061249:Batch Cell Culture Techniques / Q000295:instrumentation / Q000379:methods*; D019149:Bioreactors; D002480:Cellulase / Q000096:biosynthesis*; D005285:Fermentation; D005656:Fungal Proteins / Q000096:biosynthesis*; D007218:Industrial Microbiology / Q000379:methods*; D008031:Lignin / Q000378:metabolism; D008954:Models, Biological; D010100:Oxygen / Q000378:metabolism; D012212:Rheology; D013816:Thermodynamics; D014242:Trichoderma / Q000201:enzymology / Q000254:growth & development / Q000378:metabolism*; D014783:Viscosity
chemical_list: D005656:Fungal Proteins; C036909:lignocellulose; D008031:Lignin; D002480:Cellulase; D010100:Oxygen