Physical Properties and Antioxidant Activity of Polysaccharide from Nitraria roborowskii Kom Fruit

Crude Nitrarial roborowskii Kom fruit polysaccharide (CNRFP) was separated from Xinjiang wild Nitrarial roborowskii Kom fruit by water extraction and ethanol precipitation, and monosaccharide composition, physical properties and antioxidant activities of CNRFP were studied. The results showed that Nitrarial roborowskii Kom polysaccharide was mainly composed of glucose, arabinose, galactose, galacturonic acid, glucuronic acid, mannose, etc. The mass ratio of monosaccharides was glucose:arabinose:galactose = 5.43:2.98:1.94. CNRFP had good thermal stability in the temperature range of 25~125 °C, and the solution of the polysaccharides from nitraria macrocarpa was a pseudoplastic fluid with shear thinning and good moisture retention. When the concentration of polysaccharide was 5%, the foaming rate and emulsifying rate were 42.16% and 65.29%, respectively. The free radical scavenging ability and total reduction ability of polysaccharides from Nitrarial roborowskii Kom increased with the increase of concentration. The IC₅₀ values of CNRFP for scavenging DPPH, ABTS and hydroxyl radicals were 1.14, 0.54 and 1.11 mg/mL, respectively, and the antioxidant activity was good. The results provide a theoretical basis for the application of Nitrarial roborowskii Kom polysaccharides in food additives, pharmaceutical and materials science industries.