Characterization of Water-Soluble Extracellular Polysaccharide from Aeribacillus pallidus IM17

The production of the extracellular polysaccharide from the thermophilic bacterium Aeribacillus pallidus was carried out in the study. The polysaccharide was isolated and characterized by means of GC-MS, FT-IR, DSC, and XRD analyses. The rheological, foaming, and emulsifying properties of the polysaccharide were determined. Using a sucrose-rich medium, 27.1 mg dried EPS/100 mL was obtained with 94% carbohydrate and 1.5% protein. The monosaccharide profile of water-soluble EPS-IM17 was composed of rhamnose, arabinose, xylose, mannose, glucose, and galactose. The foaming capacity and stability of EPS-IM17 were 26.67% (+/- 4.71) and 40.01% (+/- 4.95), respectively, and the foaming stability was not affected by time. The emulsification index of EPS-IM17 was 64.54 (+/- 8.71) and decreased to 38.47 (+/- 10.44) after 24 h. EPS-IM17 had a crystalline structure. Solutions at different concentrations (10, 20, 40 mgmL(-1)) showed pseudoplastic behavior. In conclusion, this report could be a lead study for the use of Aeribacillus pallidus extracellular polysaccharide for different applications.