title: Improving the monitoring of methanol concentration during high cell density fermentation of Pichia pastoris.
abstract: The Pichia pastoris expression system is widely used for the production of recombinant proteins. A simple and efficient experimental set-up allowing on-line monitoring of the methanol concentration during the fermentation of P. pastoris based on the detection of the methanol vapor concentration in the exhaust air from fermenter by a tin dioxide (SnO2) semiconductor sensor is described. An experimental procedure to allow precise calibration of the system and to reduce methanol sensor's interferences (>95% reduction) are also presented and discussed. Accuracy and measurement error were estimated about 0.05 g x l(-1) and 6%, respectively. The efficient monitoring of methanol will help to advanced control of recombinant protein production and process optimization.
authors.affiliation: Departament d'Enginyeria Química ETSE, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain.
authors.forename: R
authors.initials: R
authors.lastname: Ramon
authors.forename: J X
authors.initials: JX
authors.lastname: Feliu
authors.forename: O
authors.initials: O
authors.lastname: Cos
authors.forename: J L
authors.initials: JL
authors.lastname: Montesinos
authors.forename: F X
authors.initials: FX
authors.lastname: Berthet
authors.forename: F
authors.initials: F
authors.lastname: Valero
mesh_terms: D019149:Bioreactors / Q000382:microbiology*; D002452:Cell Count / Q000295:instrumentation / Q000379:methods; D018929:Cell Culture Techniques / Q000295:instrumentation* / Q000379:methods; D049109:Cell Proliferation; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005246:Feedback / Q000502:physiology; D005285:Fermentation / Q000502:physiology; D005434:Flow Cytometry / Q000295:instrumentation* / Q000379:methods; D017022:Flow Injection Analysis / Q000295:instrumentation* / Q000379:methods; D008049:Lipase / Q000096:biosynthesis / Q000235:genetics; D000432:Methanol / Q000032:analysis / Q000378:metabolism*; D010843:Pichia / Q000502:physiology*; D011994:Recombinant Proteins / Q000096:biosynthesis; D012233:Rhizopus / Q000201:enzymology / Q000235:genetics; D014159:Transducers
chemical_list: D011994:Recombinant Proteins; D008049:Lipase; D000432:Methanol