Structure of the exopolysaccharide produced by Lactococcus lactis subspecies cremoris H414 grown in a defined medium or skimmed milk

Abstract

The structure of the exopolysaccharide of Lactococcus lactis subsp. cremoris H414, isolated from a defined medium or skimmed milk, was established by linkage analysis on the native polysaccharide, and by characterisation of oligosaccharide fragments, obtained by Smith degradation and partial acid hydrolysis, using methylation analysis, FABMS, EIMS, and 1H-NMR spectroscopy. The polysaccharide has the branched-pentasaccharide repeating unit: ->4)-beta-D-Galp-(1->3)-beta-D-Galp-(1->4)-[beta-D-Galp-(1->3)-beta-D-Galp-(1->3)-alpha-D-Galp-(1->.