【摘要】 目的 测定银杏叶多糖的组成、分子量、甙键类型及其对羟自由基的清除作用。方法 利用气相色谱法测定多糖组成；凝胶过滤法测定分子量；红外光谱法测定甙键类型。以·OH清除剂(甘露醇、苯甲酸)为对照，应用Fenton反应检测多糖对·OH的清除作用。结果 该多糖是由鼠李糖、阿拉伯糖、甘露糖、半乳糖组成，平均分子量为1..04×10６。红外光谱在835cm－１处有吸收。对·OH的清除作用达50%所需药物量以EC５０表示。多糖、甘露醇、苯甲酸的EC５０依次为867、3996和490μg/ml。结论 银杏叶多糖是以α甙键连接而成的杂多糖，该多糖对Fenton体系产生的·OH自由基有清除作用。更多还原

【Abstract】 Objective\ To determine the component sugars,the molecu lar weight,the forms of linkage and scavenging action to hydroxyl free radical o f GBL(Ginkgo biloba leaf) polysaccharide.Methods\ The co mponent sugar was determined by gas chromatography analysis.Its molecular weight was measured by gel filtration.The scavenging action to hydroxyl free radical w as tested by Fenton reaction contrasting with special eliminations for hydroxyl free radicals,for example, mannitol,benzoic acid.Results\ The polysa c charide was composed of rhamnose,arabinose,mannose and galactose.Its mean molecu lar weight was estimated to be 1.04×１０６.The scavenging action to hydroxyl free radical was represented by the content scavenging 50% of all hydroxyl free radical(EC５０).The EC５０ of polysaccharide,mannitol,and benzoic ac id was 867,3996 and 490μg/ml.Conclusion\ The polysaccharide is a he teropolysaccharide,its main chain is composed of αlinkage.It has a scavenging action to hydroxyl free radical by Fenton reaction.\=更多还原