Preparation of polysaccharides from Osmunda japonica (Thunb) with the potential of food additives: Structural features and functional properties

Abstract

Osmunda japonica (Thunb) is a plant with high nutritional and medicinal value. In this study, microwave-assisted extraction method was used to extract crude polysaccharides (OCPs) and pure polysaccharides (OPPs) from the tender stems and leaves of Osmunda japonica (Thunb). The yields were 22.08 ± 0.52% and 4.51 ± 0.31%, respectively. Structural analysis using (FT-IR) revealed that the OCP fraction mainly contained β-pyranose, while the OPP fraction mainly contained α-pyranose. In combination with the results of XRD analysis, all the samples exhibited an amorphous noncrystalline structure and the absence of triple-helix formation during the purification process. Functional property analysis showed that the OCPs had better water- and oil-holding capacity and emulsifying properties than those of the other fractions, and the OPPs had good foaming properties. Osmunda japonica (Thunb) polysaccharides could be used as natural additives in the fields of medicine, cosmetics, and food. Practical applications The addition of polysaccharides usually changes the food matrix, causing changes in rheological properties, which increases water retention and gel formation, resulting the thickening of the food matrix. However, there are very few data on the functional properties of the polysaccharides from Osmunda japonica (Thunb), so it is imperative to evaluate the basic functional properties of polysaccharides. The structure of plant polysaccharides was closely related to its functional properties, so the functional properties of crude polysaccharides and pure polysaccharide products obtained during the extraction and purification process were further investigated. It is expected that its functional properties will emerge in the fields of natural functional food additives, medical and health products, and increase economic benefits for the Osmunda japonica (Thunb) industry.