Characterization of a new acidic heteropolysaccharide produced by a native isolate of Lactobacillus sp. CFR-2180

Polysaccharides are being used in food and allied industries as texture improving
agents, stabilizers, for the preparation of the edible films etc. Plant and seaweed derived
polysaccharides suffer lack of assured supply and variations in quality. Microbial
exopolysaccharides (EPS) provide a valid alternative. An EPS producing lactic acid
bacterium was isolated from cabbage and identified as Lactobacillus sp. CFR-2180.
Production of 22 g/L of EPS in 24 h at 30°C was noticed. The EPS had 65% total
carbohydrates, 0.7% protein, 10% uronic acid and 2.0% moisture. Analysis by gas
chromatography revealed that the EPS is a heteropolysaccharide with the presence of
mannose, galactose and glucose in a ratio of 1:7:5, respectively. Gel permeation
chromatography and HPLC analysis of the EPS indicated presence of multiple peaks with
molecular weight ranging from 1.8 x 104 to 2.5 x 106 Da., confirming the heterogeneity
of the EPS. The results of the preliminary characterization of the EPS indicated that it is a
new EPS that has not been reported earlier.