title: Combined shifted-excitation Raman difference spectroscopy and support vector regression for monitoring the algal production of complex polysaccharides.
abstract: The applicability of shifted-excitation Raman difference spectroscopy (SERDS) in combination with signal regression analysis as an alternative and non-invasive approach for monitoring the cultivation of phototrophic microorganisms producing complex molecules of pharmaceutical relevance in a bioreactor is demonstrated. As a model system, the cultivation of the red unicellular algae Porphyridium purpureum is used for focusing on the segregation of sulfated exopolysaccharides (EPS) which exhibit antiviral activity. The spectroscopic results obtained by partial linear least squares regression (PLSR) and by nonlinear support vector regression (SVR) are discussed against the corresponding results from the reference analytics based on the phenol-sulfuric acid assay. The SERDS-approach turns out to have strong potential as a non-invasive tool for online-monitoring of biotechnological processes.
authors.affiliation: Institute of Engineering Thermodynamics, University of Erlangen-Nuremberg, Am Weichselgarten 9, 91058 Erlangen, Germany.
authors.forename: Kristina
authors.initials: K
authors.lastname: Noack
authors.forename: Björn
authors.initials: B
authors.lastname: Eskofier
authors.forename: Johannes
authors.initials: J
authors.lastname: Kiefer
authors.forename: Christina
authors.initials: C
authors.lastname: Dilk
authors.forename: Georg
authors.initials: G
authors.lastname: Bilow
authors.forename: Matthias
authors.initials: M
authors.lastname: Schirmer
authors.forename: Rainer
authors.initials: R
authors.lastname: Buchholz
authors.forename: Alfred
authors.initials: A
authors.lastname: Leipertz
mesh_terms: D011134:Polysaccharides / Q000096:biosynthesis / Q000737:chemistry*; D000461:Rhodophyta / Q000737:chemistry* / Q000378:metabolism; D013059:Spectrum Analysis, Raman / Q000379:methods*; D060388:Support Vector Machine
chemical_list: D011134:Polysaccharides