蛹虫草子实体抗氧化多糖的分离纯化及结构表征

王雅楠; 钱心燚; 雍一丹; 吴萌萌; 李意豪; 陈宇航; 尼再中; 李璐璐; 陈安徽; 张朋; 耿颖; 邵颖

doi:10.13386/j.issn1002-0306.2024070386

蛹虫草子实体抗氧化多糖的分离纯化及结构表征

Isolation, Purification, and Structural Characterization of Antioxidant Polysaccharides Isolated From the Fruiting Bodies of Cordyceps militaris

摘要

摘要: 本研究以蛹虫草子实体为原料，采用热水浸提法提取蛹虫草子实体粗多糖，然后使用不同体积分数（30%、40%、50%、60%、70%、80%和90%）乙醇分级沉淀得到分级粗多糖Y-1、Y-2、Y-3、Y-4、Y-5、Y-6和Y-7。筛选抗氧化活性最强的分级粗多糖，经DEAE-52纤维素离子交换层析及Sephadex G-150葡聚糖凝胶层析分离纯化后筛选抗氧化活性最强的均一多糖。采用高效凝胶色谱法、气相色谱法及红外光谱法对均一多糖的分子量、单糖组成及官能团等结构表征进行鉴定，并评价其体内抗氧化活性。结果发现，分级多糖Y-4的抗氧化活性最强，其经DEAE-52纤维素离子交换层析及Sephadex G-150葡聚糖凝胶层析分离纯化后得到了抗氧化活性最强的均一多糖STP-4。STP-4是由阿拉伯糖、甘露糖和葡萄糖等聚合而成的α-构型低聚糖，分子量约为1434 Da，具有O-H、C-H、COOH、C=O和C-O-C等官能团结构。另外，STP-4可以显著降低过氧化损伤小鼠血清丙二醛（Malondialdehyde, MDA）含量（P<0.01），提高超氧化物歧化酶（Superoxide dismutase, SOD）（P<0.01）和谷胱甘肽过氧化物酶（Glutathione peroxidase, GSH-Px）活性（P<0.05）。本研究为蛹虫草资源的深度开发和抗氧化活性研究提供了理论基础。

Abstract: In the present study, the fruiting bodies of Cordyceps militaris were used as raw materials to extract the crude polysaccharides Y-1, Y-2, Y-3, Y-4, Y-5, Y-6 and Y-7, which fractional precipitation using the ethanol with different volume fractions of 30%, 40%, 50%, 60%, 70%, 80% and 90%. The graded crude polysaccharide with the strongest antioxidant activity was selected to separate and purify the homogeneous polysaccharide with the strongest by DEAE-52 cellulose ion exchange chromatography and Sephadex G-150 gel chromatography. High performance gel chromatography, gas chromatography and infrared spectroscopy were used to identify the molecular weight, monosaccharide composition and functional groups of the homogeneous polysaccharide, and evaluate its antioxidant activity in vivo. The results showed that the graded polysaccharide Y-4 with the strongest antioxidant activity was isolated and purified by DEAE-52 cellulose ion exchange chromatography and Sephadex G-150 gel chromatography, and obtained a homogeneous polysaccharide STP-4 with the strongest antioxidant activity. STP-4 is an α-type configuration oligosaccharide composed of arabinose, mannose, and glucose, with a molecular weight of approximately 1434 Da. It has the functional groups such as O-H, C-H, -C≡C, C=O, and C-O-C. In addition, STP-4 can significantly reduce the malondialdehyde (MDA) content (P<0.01), increase the superoxide dismutase (SOD) activity (P<0.01), and the glutathione peroxidase (GSH-Px) activity (P<0.05) in the serum of mice with oxidative damage. This study provides a theoretical basis for the in-depth development and antioxidant activity research of Cordyceps militaris resources.