Abstract:The effects of high-energy electron beam irradiation on the physicochemical properties and anti-fatigue activity of polysaccharides from cultivated Ganodema lingzhi (GLP) were investigated. GLP was extracted using the water extraction and alcohol precipitation method, and was then purified through ion exchange chromatography and gel filtration chromatography. Different doses of high-energy electron beam irradiation were applied to the GLP, and its physicochemical properties were characterized using scanning electron microscopy and infrared spectroscopy. A weight-loaded swimming model was used to induce exercise fatigue in rats, which were then administered GLP via gavage to verify its anti-fatigue effects. The results showed that the weight-average molecular weight of GLP was 1.87 × 106 u, with an average particle size of 779.42 nm, and the anomeric carbon was in the β-configuration. As the irradiation dose increased, the molecular weight and particle size of GLP initially increased and then decreased, indicating a transition from cross-linking to depolymerization. GLP treated with 20 kGy irradiation was found to significantly increase liver glycogen content (by 31.37%) and muscle glycogen content (by 52.94%) in fatigued rats, while blood urea nitrogen content was reduced (by 41.67%) and serum lactic acid content was lowered (by 43.75%). Additionally, the irradiated GLP was shown to enhance the activity of endogenous antioxidant enzymes in rat mitochondria and reduce malondialdehyde accumulation. Compared to the positive control (rhodiola rosea glycoside), GLP treated with 20 kGy irradiation demonstrated superior anti-fatigue effects. Therefore, an appropriate dose of high-energy electron beam irradiation was deemed an ideal method for modifying GLP.
