Thermal and molecular characteristics of novel water-soluble polysaccharide from the Pteridium aquilinum and Dryopteris filix-mas

Novel water-soluble complex polysaccharides (CPS) were obtained from Pteridium aquilinum and Dryopteris filix-mas. The yield of CPS was determined to be 4.161%-5.677%. As a result of the physicochemical composition, the CPS contained 12.10–13.65% moisture, 1.983–2.686% protein, 0.123–0.916% lipids and 12.06–21.52% ash. In HPLC analysis, sugar components of the samples (glucose+fructose+saccharose+maltose+lactose) ranged between 35.85–40.98%. Peaks of the fingerprint region specific for polysaccharides were identified during FT-IR analysis. DSC analysis showed that the glassy transition temperature of the DFR sample was higher than in the other three samples. A double cold crystallization peak was detected in all samples. During TGA analysis, the CPS samples exhibited a small amount of mass loss (1.2–1.85%) between 0 and 100 °C, and the DTGmax.p1 region continued up to 215–230 °C. These findings indicate that the four types of polysaccharides have excellent thermal stability (up to 230 °C) and are applicable to high-temperature food processing.