Abstract
The highly viscous neutral exopolysaccharide, produced in large amounts by Lactobacillus fermentum TDS030603 in MRS broth and in a chemically defined medium supplemented with glucose, was investigated by GLC(-EIMS) monosaccharide and methylation analysis, periodate oxidation, MALDI-TOF mass spectrometry, and 1D/2D NMR spectroscopy. The GLC(-EIMS) analyses showed that the EPS contained D-glucose and D-galactose in an averaged molar ratio of 2.6:1.0, consisting of terminal D-Glcp, 3-substituted D-Glcp, 2,3-disubstituted D-Glcp, and 6-substituted D-Galp in an averaged molar ratio of 1.3:1.0:1.1:1.1, with a trace of terminal D-Galp (0.1). Combined with the NMR data of the EPS (previously reported constituent analysis: terminal Glcp, 3-substituted Glcp, 2,3-disubstituted Glcp, and 6-substituted Galp in an averaged molar ratio of 1.2:1.1:1.0:1.1) and oligosaccharides isolated after partial acid hydrolysis, a branched tetrasaccharide repeating unit, with some heterogeneity in the side chain, having the following structure is proposed: (Equation presented) © 2013 Elsevier Ltd.
| Original language | English |
|---|---|
| Pages (from-to) | 84-90 |
| Number of pages | 7 |
| Journal | Carbohydrate Research |
| Volume | 378 |
| DOIs | |
| Publication status | Published - 30 Jan 2013 |
Keywords
- Exopolysaccharide
- Lactic acid bacteria
- Lactobacillus fermentum
- NMR spectroscopy
- Structural analysis
- exopolysaccharide
- galactose
- glucose
- article
- carbohydrate analysis
- hydrolysis
- matrix assisted laser desorption ionization time of flight mass spectrometry
- methylation
- nonhuman
- oxidation
- priority journal