目的:研究瓜蒌多糖的分子量分布、单糖组成、抗氧化活性以及心脏保护活性。方法:采用不同浓度的乙醇(0%、10%、20%、40%、60%、80%)沉淀得到不同相对分子质量的瓜蒌多糖A、B10、B20、B40、B60、B80;采用1-苯基-3-甲基-5-吡唑啉酮(PMP)衍生化方法测定其单糖组成;通过DPPH?清除率、还原力、羟基自由基清除率测定瓜蒌多糖体外抗氧化活性;采用斑马鱼模型检测瓜蒌多糖的心脏保护活性。结果:A、B10、B20、B40、B60、B80清除DPPH?的IC_(50)分别为0.691、0.721、0.442、0.455、0.185、0.686 mg/m L,清除羟基自由基的IC_(50)分别为0.432、0.361、0.371、0.392、0.341、0.440 mg/m L,不同分子量多糖均具有较好的抗氧化活性;A、B10、B60样品具有斑马鱼心脏保护活性。结论:B60单糖组成明显不同于其他多糖,抗氧化活性最强、斑马鱼心脏保护活性最高且持续性最强,是瓜蒌发挥其抗心律失常活性的主要部位。 Objective: To study the molecular weight distribution, monosaccharide composition, antioxidant activity and cardioprotective activity of polysaccharides from Melon. Methods: The polysaccharides A, B10, B20, B40, B60 and B80 with different molecular weights were precipitated by different concentrations of ethanol (0%, 10%, 20%, 40%, 60%, 80% -Phenyl-3-methyl-5-pyrazolone (PMP) derivatization was used to determine the monosaccharide composition. The in vitro antioxidant activities of polysaccharides were determined by DPPH? Scavenging ability, reducing power and hydroxyl radical scavenging activity. The zebrafish model was used to test the cardioprotective activity of polysaccharides from Melon. Results: The IC50 of DPPH? Scavenging by A, B10, B20, B40, B60 and B80 were 0.691,0.721,0.442,0.455,0.185,0.686 mg / m L, respectively. The IC50 of hydroxyl radical scavenging was 0.432,0.361,0.371,0.392,0.341,0.440 mg / m L, different molecular weight polysaccharides have good antioxidant activity; A, B10, B60 samples have zebrafish cardioprotective activity. CONCLUSION: The B60 monosaccharide composition is obviously different from other polysaccharides and has the strongest antioxidant activity. The zebrafish has the highest cardioprotective activity and the strongest persistence. It is the main part of the melon that exerts its anti-arrhythmic activity.