Optimized Protocol for Production and Extraction of Colanic Acid from E. coli Culture

Abstract

Objective: Colanic acid (CA) is a promising and actively studied polysaccharide, which geroprotective and stimulating properties have already been described in animal models. Different protocols are used to isolate and purify CA in research, some of which may result in contamination with proteins, DNA, and other polysaccharides. Methods: In order to effectively further investigate the biological properties of CA, we developed 5 protocols for CA isolation, differed in cultivation condition, protein precipitation, and polysaccharide precipitants. Results and Discussion: We found that the most suitable protocol for CA isolation includes protein removal with trichloroacetic acid and polysaccharide precipitation with ethanol (95%, 3 volumes). Conclusions: Such a simple protocol will serve to standardize CA studies and can be applied to obtain large volumes of polysaccharide.