NMR spectroscopic analysis of exopolysaccharides produced by Leuconostoc citreum and Weissella confusa.

Dextrans are the main exopolysaccharides produced by Leuconostoc species. Other dextran-producing lactic acid bacteria include Streptococci, Lactobacilli, and Weissella species. Commercial production and structural analysis has focused mainly on dextrans from Leuconostoc species, particularly on Leuconostoc mesenteroides strains. In this study, we used NMR spectroscopy techniques to analyze the structures of dextrans produced by Leuconostoc citreum E497 and Weissella confusa E392. The dextrans were compared to that of L. mesenteroides B512F produced under the same conditions. Generally, W. confusa E392 showed better growth and produced more EPS than did L. citreum E497 and L. mesenteroides B512F. Both L. citreum E497 and W. confusa E392 produced a class 1 dextran. Dextran from L. citreum E497 contained about 11% alpha-(1-->2) and about 3.5% alpha-(1-->3)-linked branches whereas dextran from W. confusa E392 was linear with only a few (2.7%) alpha-(1-->3)-linked branches. Dextran from W. confusa E392 was found to be more linear than that of L. mesenteroides B512F, which, according to the present study, contained about 4.1% alpha-(1-->3)-linked branches. Functionality, whether physiological or technological, depends on the structure of the polysaccharide. Dextran from L. citreum E497 may be useful as a source of prebiotic gluco-oligosaccharides with alpha-(1-->2)-linked branches, whereas W. confusa E392 could be a suitable alternative to widely used L. mesenteroides B512F in the production of linear dextran.

[1]  S. A. Meyer,et al.  Facilitated isolation, purification, and analysis of glucuronoxylomannan of Cryptococcus neoformans , 1991, Infection and immunity.

[2]  L De Vuyst,et al.  Heteropolysaccharides from lactic acid bacteria. , 1999, FEMS microbiology reviews.

[3]  F. R. Seymour,et al.  Correlation of the structure of dextrans to their 1H-n.m.r. Spectra , 1979 .

[4]  Anna Sundheq,et al.  Determination of hemicelluloses and pectins in wood and pulp fibres by acid methanolysis and gas chromatography , 1996 .

[5]  G. Bodenhausen,et al.  Natural abundance nitrogen-15 NMR by enhanced heteronuclear spectroscopy , 1980 .

[6]  P. Würtz,et al.  H2BC: a new technique for NMR analysis of complex carbohydrates. , 2006, Carbohydrate research.

[7]  M. Williamson,et al.  NMR studies of dextran oligomer interactions with model polyphenols , 1995 .

[8]  T. Leathers,et al.  A method for surveying and classifying Leuconostoc spp. glucansucrases according to strain-dependent acceptor product patterns , 2005, Journal of Industrial Microbiology and Biotechnology.

[9]  Wolfgang Bermel,et al.  Gradient selection in inverse heteronuclear correlation spectroscopy , 1993 .

[10]  N. Nyberg,et al.  Heteronuclear two-bond correlation: suppressing heteronuclear three-bond or higher NMR correlations while enhancing two-bond correlations even for vanishing 2J(CH). , 2005, Journal of the American Chemical Society.

[11]  S. Bozonnet,et al.  Homopolysaccharides from lactic acid bacteria , 2001 .

[12]  Mikihiko Kobayashi,et al.  Structures of three α-d-(1→2)-branched oligosaccharides isolated from Leuconostoc mesenteroides NRRL B-1299 dextran , 1984 .

[13]  P. Monsan,et al.  Degradation and fermentation of alpha-gluco-oligosaccharides by bacterial strains from human colon: in vitro and in vivo studies in gnotobiotic rats. , 1995, The Journal of applied bacteriology.

[14]  Wim Soetaert,et al.  Leuconostoc dextransucrase and dextran: production, properties and applications , 2005 .

[15]  C. Ch,et al.  Glucooligosaccharides from Leuconostoc mesenteroides B-742 (ATCC 13146): a potential prebiotic. , 2002 .

[16]  P. Monsan,et al.  Glucansucrases: molecular engineering and oligosaccharide synthesis , 2000 .

[17]  M. Collins,et al.  Taxonomic studies on some leuconostoc-like organisms from fermented sausages: description of a new genus Weissella for the Leuconostoc paramesenteroides group of species. , 1993, The Journal of applied bacteriology.

[18]  M. M. Bradford.  A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. , 1976, Analytical biochemistry.

[19]  I. Maddox,et al.  Exopolysaccharides from lactic acid bacteria: perspectives and challenges. , 2003, Trends in biotechnology.

[20]  A. Gil-Serrano,et al.  Structural analysis of the exopolysaccharides produced by Lactobacillus spp. G-77. , 1998, Carbohydrate research.

[21]  M. Rance,et al.  Sensitivity improvement in isotropic mixing (TOCSY) experiments , 1990 .

[22]  G. Gibson,et al.  In vitro fermentability of dextran, oligodextran and maltodextrin by human gut bacteria , 2000, British Journal of Nutrition.

[23]  P. Vandamme,et al.  Taxonomic study of Weissella confusa and description of Weissella cibaria sp. nov., detected in food and clinical samples. , 2002, International journal of systematic and evolutionary microbiology.

[24]  H. M. Tsuchiya,et al.  Characterization and Classification of Dextrans from Ninety-six Strains of Bacteria1b , 1954 .

[25]  E. J. Bourne,et al.  Studies on dextrans and dextranases. XI. The structure of a dextran elaborated by Leuconostoc mesenteroides NRRL B-1299. , 1974, Carbohydrate research.

[26]  T. Heinze,et al.  Functional Polymers Based on Dextran , 2006 .

[27]  Young-Min Kim,et al.  Dextran molecular size and degree of branching as a function of sucrose concentration, pH, and temperature of reaction of Leuconostoc mesenteroides B-512FMCM dextransucrase. , 2003, Carbohydrate research.

[28]  E. Chen,et al.  Structural analysis of leuconostoc dextrans containing 3-O-α-d-glucosylated α-d-glucosyl residues in both linear-chain and branch-point positions, or only in branch-point positions, by methylation and by 13C-N.M.R. spectroscopy , 1979 .

[29]  E. Chen,et al.  Structural analysis of dextrans containing 2-O-α-d-glucosylated α-d-glucopyranosyl residues at the branch points, by use of 13C-nuclear magnetic resonance spectroscopy and gas-liquid chromatography-mass spectrometry☆ , 1979 .

[30]  C. Andrieux,et al.  Compared effects of three oligosaccharides on metabolism of intestinal microflora in rats inoculated with a human faecal flora , 1997, British Journal of Nutrition.

[31]  Harjinder Singh,et al.  Evaluation and modification of existing methods for the quantification of exopolysaccharides in milk-based media , 2005 .

[32]  H. Mark,et al.  Encyclopedia of polymer science and engineering , 1985 .

[33]  P. Ruas-Madiedo,et al.  Invited review: methods for the screening, isolation, and characterization of exopolysaccharides produced by lactic acid bacteria. , 2005, Journal of dairy science.

[34]  S. Le Borgne,et al.  Characterization of a cell-associated inulosucrase from a novel source: A Leuconostoc citreum strain isolated from Pozol, a fermented corn beverage of Mayan origin , 2002, Journal of Industrial Microbiology and Biotechnology.

[35]  R. England,et al.  Methylation analyses of NRRL dextrans by capillary gas-liquid chromatography , 1986 .

[36]  E. J. Bourne,et al.  Studies on dextrans and dextranases. X. Types and percentages of secondary linkages in the dextrans elaborated by Leuconostoc mesenteroides NRRL B-1299. , 1972, Carbohydrate research.

[37]  G. J. Walker,et al.  Dextran structural details from high-field proton NMR spectroscopy , 1990 .

[38]  F. R. Seymour,et al.  Determination of the structure of dextran by 13C-nuclear magnetic resonance spectroscopy. , 1976, Carbohydrate research.

[39]  G. Wider.  Technical aspects of NMR Spectroscopy with biological macromolecules and studies of hydration in solution , 1998 .