Structure of an Extracellular Polysaccharide from a Strain of Lactic Acid Bacteria

Abstract A new extracellular polysaccharide (EPS‐I) isolated and purified from Z 222 , a strain of Lactic acid bacteria has been investigated. Sugar composition analysis, methylation analysis and 1 H NMR and 13 C NMR spectroscopy reveal that the EPS‐I is composed of a pentasaccharide repeating unit. The sequence of sugar residue was determined by using two‐dimensional NMR spectroscopy, including heteronuclear multiple‐bond correlation (HMBC) and nuclear overhauser effect spectroscopy (NOESY).