Structure of the cell wall polysaccharides of probiotic bifidobacteria Bifidobacteriumbifidum BIM B-465.

The composition and structure of cell wall polysaccharides of a biotechnologically promising probiotic strain of bifidobacteria Bifidobacteriumbifidum BIM B-465 were established by monosaccharide and methylation analyses along with 2D (1)H-(1)H homonuclear and (1)H-(13)C heteronuclear correlation NMR spectroscopy. The major polysaccharide represents a branched glucogalactan consisting of heptasaccharide repeating units having the following structure: -->6)-alpha-D-Glcp-(1-->3)-beta-D-Galf-(1-->3)-alpha-D-Glcp-(1-->2)-beta-D-Galf-(1-->3)-alpha-D-Galp-(1-->3)-alpha-D-Glcp-(1--> [structure: see the text]. The second isolated polysaccharide is a branched glucan with the main chain of (1-->6)-linked alpha-d-glucopyranose residues, approximately 60% of which are 2-substituted with a single alpha-d-glucopyranosyl group. This polysaccharide is a characteristic of various microorganisms, including some lactobacteria studied earlier.