The slime forming bacteria Brevundimonas vesicularis sp. was isolated from a paper mill and its EPS was produced on laboratory scale. After production, the exopolysaccharide (EPS) was purified and analysed for its purity and homogeneity, HPSEC revealed one distinct population with a molecular mass of more than 2,000 kDa. The protein content was around 9 w/w%. The sample was analysed to determine its chemical structure. The EPS was found to consist of rhamnose, glucose, galacturonic acid and glucuronic acid. Due to the presence of uronic acids the molar ratio between the four sugars found varies from 3:5:2:4 by sugar composition analyses after methanolysis to 1:1:1:1 found by NMR. A repeating unit with a molecular mass of 678 Da was confirmed by MALDI-TOF mass spectrometry after mild acid treatment. 13C and 1H hetero- and homonuclear 2D NMR spectroscopy of the native and partial hydrolysed EPS revealed a [formula: see text].
NMR, structure, structural, repeating unit, molecular, acid, protein, bacteria, uronic acid, exopolysaccharide, structure elucidation, chemical, chemical structure, sugar, production, elucidation, MALDI, Brevundimonas vesicularis, composition, content, EPS, galacturonic acid, glucose, glucuronic acid, homogeneity, methanolysis, molecular mass, population, purified, purity, rhamnose, slime, sugars, Pulp and Paper Industrym, 1H and 13C NMR analyses
NCBI PubMed ID: 12431884Journal NLM ID: 0043535Publisher: Elsevier
Correspondence: fons.voragen@chem.fdsci.wag-ur.nl
Institutions: Wageningen University, Department of Agrotechnology and Food Sciences, Laboratory of Food Chemistry, Bomenweg 2, NL-6703 HD Wageningen, The Netherlands, Wageningen NMR Centre, Laboratory of Biophysics, PO Box 8128, NL-6700 ET Wageningen, The Netherlands, VTT Biotechnology, PO Box 1500, FIN-02044 VTT Espoo, Finland
Methods: 13C NMR, 1H NMR, partial acid hydrolysis, methanolysis, HPSEC
Found