Abstract

Weissella hellenica SKkimchi3 produces the higher exopolysaccharide (EPS) on sucrose than lactose, glucose, and fructose at pH 5 and 20°C. Sucrose was exclusively used to cultivate SKkimchi3 in all experiments base on the EPS production tests. The molecular mass of EPS, as determined by gel permeation chromatography, was 203,000. 1H and 13C NMR analysis indicated that the identity of EPS may be a glucan. When EPS, starch, and cellulose was treated with α-amylase, glucoamylase, glucosidase, and cellulase, glucose was produced from starch and cellulose but was not produced from EPS. Based on HPLC analysis, elemental analysis, 1H and 13C NMR analysis, and enzymatic hydrolysis tests, EPS was estimated to be a glucan. EPS suspension was not precipitated even by centrifugation at 10,000×g for 60 min, and EPS made the fermented milk and bacterial culture viscous.

• Keywords: exopolysaccharide; β-glucan; NMR-spectroscopy; lactic acid bacteria; Weissella hellenica