探究灰树花子实体多糖（GFP）的结构特性，同时考察其对小鼠运动耐力的影响，为后续灰树花多糖的深入研究提供参考。通过超声波、水提醇沉法获得灰树花粗多糖，采用DE-52纤维素柱和Sephadex G-100进行分离纯化，在扫描电镜下观察多糖的形貌特征，高效凝胶渗透色谱分析多糖的分子量，红外光谱分析多糖糖苷键构型，高效液相色谱测定多糖的单糖组成。构建小鼠力竭游泳和转棒疲劳实验模型，通过测定小鼠体内肝糖原（Hepatic Glycogen，HG）、肌糖原（Muscle Glycogen，MG）及血清生化指标，考察多糖对小鼠运动耐力的作用。结果表明，GFP纯化后分离得到3个多糖组分，GFP-A1的占比最大，得率为62.98%，其重均分子量为18 374 u，异头碳为α构型，由鼠李糖、葡萄糖、半乳糖、岩藻糖组成，摩尔比为1:10.52:11.38:18.67。小鼠的动物实验结果显示，与CK组相比，GFP-A1低、中、高剂量组的小鼠力竭游泳时间和转棒疲劳时间均显著提高（P<0.05），HG、MG含量和超氧化物歧化酶（Superoxide Dismutase，SOD）活性同样显著增加（P<0.05），血乳酸（Blood Lactic Acid，BLA）、血尿素氮（Blood Urea Ntrogen，BUN）、丙二醛（Malondialdehyde，MDA）含量则显著降低（P<0.05），表明GFP-A1可以显著提高小鼠的运动耐力，且呈剂量依赖关系。结果表明，从灰树花子实体中提取的GFP-A1具有明显提高小鼠运动耐力的作用，该研究为灰树花多糖在运动食品领域上的开发应用提供了理论依据，具有广阔的应用前景。

The structural characteristics of polysaccharides from Grifola frondosa (GFP) and their effects on exercise endurance in a mouse model were assessed. The crude polysaccharides of G. frondosa were obtained by ultrasound-assisted aqueous extraction followed by ethanol precipitation. The crude polysaccharides were separated with a DE-52 column and purified using a Sephadex G-100 column. Thereafter, scanning electron microscopy was employed to evaluate the morphological characteristics of GFP. Meanwhile, molecular weight of GFP was analyzed by HPGPC, and the glycosidic bond configuration was determined by infrared spectroscopy. Finally, the monosaccharide composition was determined by HPLC. A mouse model for exhaustive swimming and rotarod fatigue was established. The hepatic glycogen (HG), muscle glycogen (MG), and serum biochemical indices of the mice were evaluated to assess the effects of GFP on exercise endurance. Three polysaccharide components were separated following GFP purification; GFP-A1 was most abundant with a 62.98% yield. GFP-A1 had an average molecular weight of 18 374 u, and anomeric carbon was in α configuration. Moreover, it comprised rhamnose, glucose, galactose, and fucose at a molar ratio of 1:10.52:11.38:18.67. The mouse model revealed that compared with the CK group, the groups treated with low-, medium-, or high-dose GFP-A1 exhibited significantly longer exercise in the exhaustive swimming and rotarod fatigue tests (P<0.05). Meanwhile, the HG and MG contents, as well as the SOD activity were markedly increased in the GFP-A1-treated groups (P<0.05), whereas the blood lactic acid, blood urea nitrogen, and serum malondialdehyde levels were significantly reduced (P<0.05). These results indicate that GFP-A1 can significantly improve the exercise endurance of mice in a dose-dependent manner. Hence, this study provides a theoretical basis for the development and application of Grifola frondose-derived polysaccharides, which are believed to have broad application potential in sports nutrition.

河南省科技支撑项目（2018-ZZJH-170）；河南省中医药科学研究专项课题（20-21ZY2148）