基于膜技术的灵芝粗多糖分级分离及抗氧化活性比较

本文主要研究膜分离技术对灵芝粗多糖分级分离效果及其抗氧化活性的影响。以灵芝子实体为原料，通过热水浸提后用100、10和1 kDa超滤膜多级组合对灵芝粗多糖进行分级分离，分别记为GLP100、GLP10和GLP1。比较3种不同孔径膜对灵芝粗多糖的分级效果、理化性质和抗氧化活性的差异。傅里叶红外变换光谱分析结果证明3种多糖样品均具有典型的β-型糖苷键吸收峰，刚果红与圆二色谱分析证明了3种粗多糖是具有螺旋结构的多糖，且GLP100和GLP10是具有三螺旋结构的多糖。SEM结果表明三种多糖颗粒大小明显不同，进一步验证了不同膜是可以对灵芝粗多糖进行分级。还原力、OH自由基、2, 2’-联氮双（3-乙基苯并噻唑啉-6-磺酸）二铵盐阳离子自由基（ABTS自由基）和1, 1-二苯基-2-三硝基苯肼自由基（DPPH自由基）清除结果表明，3种粗多糖样品均具有一定的抗氧化能力，但存在些许差异。其中三种多糖还原力十分接近，GLP100的OH和DPPH自由基清除能力好于其他两种多糖, GLP1的ABTS自由基清除能力比其他两种多糖效果更好。实验结果表明，膜分离技术可以有效地对灵芝多糖进行分级。

Fractionation and Antioxidant of Crude Polysaccharide from Ganoderma lucidum Based on Membrane Technology

Effects of membrane technology on the separation of crude polysaccharides from Ganoderma lucidum and its antioxidant activity had been studied. Fruiting body of Ganoderma lucidumwas leached by hot water, 100, 10 and 1 kDa ultrafiltration membrane were used to classify these crude polysaccharides recorded as GLP100, GLP10 and GLP1. Physicochemical properties and antioxidant activity of crude polysaccharides were compared. It had been demonstrated that three polysaccharides all have typical β-glucosidic bond absorption peaks by FTIR analysis. Congo red and circular dichroism analysis showed that the three crude polysaccharides were helix polysaccharides, GLP100 and GLP10 were triple helix polysaccharides. Results of SEM showed that the sizes of the three polysaccharides were different, which further verified that the different membranes could be used to grade the Ganoderma lucidum polysaccharides. All the three crude polysaccharides showed certain antioxidant capacity but some differences by reducing power, OH, 2, 2'-diazobis(3-ethylbenzothiazolin-6-sulfonic acid) diammonium salt cationic radical, 1, 1-diphenyl-2-trinitrobenzene hydrazine free radical scavenging. Among them, the reducing power of GLP100 was very close, and the scavenging ability of OH, ABTS and DPPH free radicals of GLP100 was better than that of the other two polysaccharides, The ABTS radical scavenging ability of GLP1 was better than the other two polysaccharides. Results showed that multistage membrane separation technology could effectively classify the polysaccharides of Ganoderma lucidum.