Variations in the molecular weight (MW) of polysaccharides may lead to different pharmacological functions. Hierarchical alcohol precipitation is presently the most popular method of separating polysaccharides. However, as polysaccharide molecules in solution becomes dehydrated in ethanol, the conformation transforms and becomes assembled via intramolecular hydrogen bonding, which can complicate studies on the biological activities of polysaccharides. This work developed an integrated tandem hybrid membrane technology (ITHMT) to separate polysaccharides extracted from Lycium barbarum L. into fractions. The polysaccharide fractions LBP1, LBP2, LBP3, and LBP4 were separated using ITHMT. Preliminary structural analysis including homogeneity, molecular weight, monosaccharide composition, scanning electron microscopy and thermogravimetric analysis were investigated. Both LBP3 and LBP4 had symmetrical single peaks and were considered as one homogeneous polysaccharide. A lower MW cut-off for membrane elements was associated with increased polysaccharide homogeneity. LBP1∼LBP4 were found to be heteropolysaccharides and comprised rhamnose, galactose, glucose, mannose, and galacturonic acid with different molar ratios and MW. The MW of LBP1∼LBP4 were 225.6 kDa, 140.2 kDa, 65.0 kDa, and 38.3 kDa, respectively. Four polysaccharide fractions had unique morphologies, good thermal stabilities and different antioxidant effects. The LBP4 fraction exerted significant antioxidant effects against superoxide anion radicals and ferric-reducing antioxidant effect in vitro, as well as superoxide anion radicals in vivo, indicated L. barbarum polysaccharides with different molecular weight did had different antioxidant activity. All polysaccharides reduced the levels of superoxide anions in mitochondria but could not scavenge cytoplasmic H₂O₂, indicating that the antioxidant capacity of L. barbarum polysaccharides is achieved through the removal of superoxide anions from intracellular mitochondria.

多糖分子量（MW）的变化可能导致不同的药理功能。分级醇沉淀法是目前分离多糖的最流行方法。然而，由于溶液中的多糖分子在乙醇中脱水，其构象通过分子内氢键转变并组装，这会使对多糖生物学活性的研究复杂化。这项工作开发了一种集成的串联杂交膜技术（ITHMT）来分离从枸杞中提取的多糖L.分成几部分。使用ITHMT分离多糖级分LBP1，LBP2，LBP3和LBP4。初步研究了结构的均一性，分子量，单糖组成，扫描电镜和热重分析。LBP3和LBP4均具有对称的单峰，被认为是一种均质多糖。膜元件的较低的MW截止值与增加的多糖均质性相关。发现LBP1〜LBP4是杂多糖，包括鼠李糖，半乳糖，葡萄糖，甘露糖和半乳糖醛酸，具有不同的摩尔比和分子量。LBP1〜LBP4的MW分别为225.6kDa，140.2kDa，65.0kDa和38.3kDa。四种多糖级分具有独特的形态，良好的热稳定性和不同的抗氧化作用。在体外以及体内的超氧阴离子自由基表明，不同分子量的枸杞多糖确实具有不同的抗氧化活性。所有多糖均能降低线粒体中超氧阴离子的含量，但不能清除细胞质中的H ₂ O ₂，表明通过去除细胞内线粒体中的超氧阴离子可以达到枸杞多糖的抗氧化能力。