Preparation of Exopolysaccharide Synthesized by Lactic Acid Bacteria.

Polysaccharides produced by lactic acid bacteria are divided into two classes based on their biosynthesis and structure. Nevertheless, the procedures for isolation, purification, and chemical analysis of these polymers are very similar. This chapter introduces the techniques that are used to prepare exopolysaccharides from lactic acid bacteria; both large- and small-scale preparation methods are described. The chapter consists of three sections, covering precipitation (using ethanol or trichloroacetic acid), ion-exchange chromatography, and ultrafiltration. Technical advisory notes on the individual steps are also provided.