title: Study of the rheological properties of a fermentation broth of the fungus Beauveria bassiana in a bioreactor under different hydrodynamic conditions.
abstract: Fermentation with filamentous fungi in a bioreactor is a complex dynamic process that is affected by flow conditions and the evolution of the rheological properties of the medium. These properties are mainly affected by the biomass concentration and the morphology of the fungus. In this work, the rheological properties of a fermentation with the fungus Beauveria bassiana under different hydrodynamic conditions were studied and the rheological behavior of this broth was simulated through a mixture of carboxymethyl cellulose sodium and cellulose fibers (CMCNa-SF). The bioreactor was a 10 L CSTR tank operated at different stir velocities. Rheological results were similar at 100 and 300 rpm for both systems. However, there was a significant increase in the viscosity accompanied by a change in the consistence index, calculated according to the power law model, for both systems at 800 rpm. The systems exhibited shear-thinning behavior at all stir velocities, which was determined with the power law model. The mixing time was observed to increase as the cellulose content in the system increased and, consequently, the efficiency of mixing diminished. These results are thought to be due to the rheological and morphological similarities of the two fungal systems. These results will help in the optimization of scale-up production of these fungi.
authors.affiliation: Unit of Food and Biotechnology, Technological Institute of Durango, Av. Felipe Pescador 1830 Ote, 34080 Durango, Dgo., Mexico. diolamarina@hotmail.com
authors.forename: Diola Marina
authors.initials: DM
authors.lastname: Núñez-Ramírez
authors.forename: Luis
authors.initials: L
authors.lastname: Medina-Torres
authors.forename: José Javier
authors.initials: JJ
authors.lastname: Valencia-López
authors.forename: Fausto
authors.initials: F
authors.lastname: Calderas
authors.forename: Javier
authors.initials: J
authors.lastname: López Miranda
authors.forename: Hiram
authors.initials: H
authors.lastname: Medrano-Roldán
authors.forename: Aquiles
authors.initials: A
authors.lastname: Solís-Soto
mesh_terms: D052982:Beauveria / Q000737:chemistry / Q000254:growth & development / Q000378:metabolism*; D019149:Bioreactors / Q000382:microbiology*; D002266:Carboxymethylcellulose Sodium / Q000378:metabolism; D002482:Cellulose / Q000378:metabolism; D003470:Culture Media / Q000737:chemistry / Q000378:metabolism; D005285:Fermentation; D057446:Hydrodynamics; D007218:Industrial Microbiology / Q000295:instrumentation / Q000379:methods*; D007700:Kinetics; D012212:Rheology; D014783:Viscosity
chemical_list: D003470:Culture Media; D002482:Cellulose; D002266:Carboxymethylcellulose Sodium