On-line cell mass monitoring of Saccharomyces cerevisiae cultivations by multi-wavelength fluorescence

Martin Brian Haack, Anna Eliasson, Lisbeth Olsson

    Research output: Contribution to journalJournal articleResearchpeer-review


    The catalyst in bioprocesses, i.e. the cell mass, is one of the most challenging and important variables to monitor in bioprocesses. In the present study, cell mass in cultivations with Saccharomyces cerevisiae was monitored on-line with a non-invasive in situ placed sensor measuring multi-wavelength culture fluorescence. The excitation wavelength ranged from 270 to 550 nm with 20 nm steps and the emission wavelength range was from 310 to 590 nm also with 20 nm steps. The obtained spectra were analysed chemometrically with the multi-way technique, parallel factor analysis (PARAFAC), resulting in a decomposition of the multivariate fluorescent landscape, whereby underlying spectra of the individual intrinsic fluorophors present in the cell mass were estimated. Furthermore, gravimetrically determined cell mass concentration was used together with the fluorescence spectra for calibration and validation of multivariate partial least squares (PLS) regression models. Both two- and three-way models were calculated, the models behaved similarly giving root mean square error of prediction (RMSEPs) of 0.20 and 0.19 g l(-1), respectively, when test set validation was used. Based on this work, it is evident that on-line monitoring of culture fluorescence can be used for estimation of the cell mass concentration during cultivations.
    Original languageEnglish
    JournalJournal of Biotechnology
    Pages (from-to)199-208
    Publication statusPublished - 2004


    Dive into the research topics of 'On-line cell mass monitoring of Saccharomyces cerevisiae cultivations by multi-wavelength fluorescence'. Together they form a unique fingerprint.

    Cite this