大果白刺多糖的物理特性及抗氧化活性研究

吴潇霞; 陈楠; 白冰瑶; 张丽; 陈计峦; 宋丽军

doi:10.13386/j.issn1002-0306.2021040312

大果白刺多糖的物理特性及抗氧化活性研究

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

摘要

摘要: 以新疆野生大果白刺果实为原料，采用水提醇沉法分离大果白刺粗多糖（CNRFP），并对其单糖组成、物理特性和抗氧化活性进行研究。结果表明，大果白刺多糖主要由葡萄糖、阿拉伯糖、半乳糖、半乳糖醛酸、葡萄糖醛酸、甘露糖等组成，单糖组成质量比为葡萄糖:阿拉伯糖:半乳糖=5.43:2.98:1.94。大果白刺多糖在25~125 ℃范围内具有良好的热稳定性；大果白刺多糖溶液是具有剪切变薄的假塑性流体，且有良好的保湿性。此外，还具有良好的发泡能力和乳化能力，当大果白刺多糖浓度为5%时，其发泡率和乳化率分别是42.16%和65.29%。大果白刺多糖对自由基清除能力和总还原能力均随浓度增大而增大。CNRFP的清除DPPH、ABTS和羟基自由基半数清除率浓度（IC₅₀）值分别为是1.14、0.54和1.11 mg/mL，抗氧化活性良好。研究结果为大果白刺多糖在食品添加剂、制药和材料科学行业中的应用提供理论依据。

Abstract: 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.