Purification and characterization of a highly viscous polysaccharide produced by Paenibacillus strain. (April 2018) - Xu, Haiyang
Graphical abstract: Highlights: Structure of a 7.3 × 10 6 Da polysaccharide produced by Paenibacillus strain was determined. The purified polysaccharide PA showed anti-shear, thermo- and saline-tolerant abilities. PA is a potential additive for rheological modification, such as thickening and stabilizing. Abstract: The linear, 7.3 × 10 6 Da polysaccharide (PA) was purified from the extracellular polymeric product of Paenibacillus mucilaginosus WL412. Rheological results revealed that PA solution was typical shear-thinning fluid and it was more viscous than xanthan gum solution under the same conditions. Besides, PA formed a weak gel-like structure and the anti-shear, heat-resistant, and saline tolerant abilities were preferable to xanthan gum in the testing temperature range of 10–85 °C on the basis of thixotropy and oscillation analyses. Afterwards, the chemical structure of PA was elucidated by means of methylation-GC/MS, and 1D- and 2D-NMR spectra. PA consisted of three types of glycosides, namely mannoside, glucoside, and galactoside with molar ratio of 1.89:2.11:1.00. Besides, an acetyl group existed in every repeating unit. The possible structure of PA was identified as →4)α-Glc(1 → 2)α-Man(1 → 3)β-Glc(1 → 3)α-Man(6-Ac)(1 → 3)β-Gal(1→. These results indicate that PA is a potential additive for rheological modification, such as thickener and stabilizer.