title: Non-invasive online detection of microbial lysine formation in stirred tank bioreactors by using calorespirometry.
abstract: Non-invasive methods for online monitoring of biotechnological processes without compromising the integrity of the reactor system are very important to generate continuous data. Even though calorimetry has been used in conventional biochemical analysis for decades, it has not yet been specifically applied for online detection of product formation at technical scale. Thus, this article demonstrates a calorespirometric method for online detection of microbial lysine formation in stirred tank bioreactors. The respective heat generation of two bacterial strains, Corynebacterium glutamicum ATCC 13032 (wild-type) and C. glutamicum DM1730 (lysine producer), was compared with the O2 -consumption in order to determine whether lysine was formed. As validation of the proposed calorespirometric method, the online results agreed well with the offline measured data. This study has proven that calorespirometry is a viable non-invasive technique to detect product formation at any time point.
authors.affiliation: RWTH Aachen, AVT-Biochemical Engineering, Worringer Weg, 52074 Aachen, Germany.
authors.forename: Lars
authors.initials: L
authors.lastname: Regestein
authors.forename: Thomas
authors.initials: T
authors.lastname: Maskow
authors.forename: Andreas
authors.initials: A
authors.lastname: Tack
authors.forename: Ingo
authors.initials: I
authors.lastname: Knabben
authors.forename: Martin
authors.initials: M
authors.lastname: Wunderlich
authors.forename: Johannes
authors.initials: J
authors.lastname: Lerchner
authors.forename: Jochen
authors.initials: J
authors.lastname: Büchs
mesh_terms: D018533:Biomass; D019149:Bioreactors / Q000382:microbiology*; D001709:Biotechnology / Q000295:instrumentation* / Q000379:methods*; D002151:Calorimetry / Q000379:methods*; D048230:Corynebacterium glutamicum / Q000737:chemistry* / Q000378:metabolism; D005285:Fermentation; D008239:Lysine / Q000032:analysis* / Q000378:metabolism; D015203:Reproducibility of Results
chemical_list: D008239:Lysine