Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7793542 | Carbohydrate Polymers | 2014 | 8 Pages |
Abstract
An exopolysaccharide known as dextran was produced by Leuconostoc mesenteroides KIBGE-IB22 (wild) and L. mesenteroides KIBGE-IB22M20 (mutant). The structure was characterized using FTIR, 1H NMR, 13C NMR and 2D NMR spectroscopic techniques, whereas surface morphology was analyzed using SEM. A clear difference in the spectral chemical shift patterns was observed in both samples. All the spectral data indicated that the exopolysaccharide produced by KIBGE-IB22 is a mixture of two biopolymers. One was dextran in α-(1 â 6) configuration with a small proportion of α-(1 â 3) branching and the other was levan containing β-(2 â 6) fructan fructofuranosyl linkages. However, remarkably the mutant only produced dextran without any concomitant production of levan. Study suggested that the property of KIBGE-IB22M20, regarding improved production of high molecular weight dextran in a shorter period of fermentation time without any contamination of other exopolysaccharide, could be employed to make the downstream process more feasible and cost effective on large scale.
Keywords
TOCSYtwo-dimensional nuclear magnetic resonance spectroscopyNOESYHSQCLeuconostoc mesenteroidesEPS1H NMRDQF-COSY2D NMRNuclear Overhauser Effect SpectroscopYExopolysaccharidemutationMutantDextranROESY13C NMRFTIRrotating frame nuclear Overhauser effect spectroscopyproton nuclear magnetic resonance spectroscopyTotal correlation spectroscopyheteronuclear single-quantum correlation spectroscopyheteronuclear multiple-bond correlation spectroscopyHomonuclear correlation spectroscopyFourier-transform infraredLevanSEMScanning electron microscopywild typeHMBC یا Heteronuclear Multiple Bond CorrelationCOSY
Related Topics
Physical Sciences and Engineering
Chemistry
Organic Chemistry
Authors
Nadir Naveed Siddiqui, Afsheen Aman, Alba Silipo, Shah Ali Ul Qader, Antonio Molinaro,