银杏叶多糖的化学及清除羟自由基作用

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。

The study of chemical and scavenging action to hydroxyl free radical of polysaccha rides of Ginkgo biloba leaf

Objective To determine the component sugars, the molecular weight, the forms of linkage and scavenging action to hydroxyl free radical of GBL( Ginkgo biloba leaf) polysaccharide. Methods The component sugar was determined by gas chromatography analysis. Its molecular weight was measured by gel filtration. The scavenging action to hydroxyl free radical was tested by Fenton reaction contrasting with special eliminations for hydroxyl free radicals, for example, mannitol,benzoic acid. Results The polysaccharide was composed of rhamnose, arabinose, mannose and galactose. Its mean molecular weight was estimated to be The scavenging action to hydroxyl free radical was represented by the content scavenging 50% of all hydroxyl free radical The of polysaccharide, mannitol, and benzoic acid was 867,3996 and 490μg/ml. Conclusion The polysaccharide is a heteropolysaccharide, its main chain is composed of a-linkage. It has a scavenging action to hydroxyl free radical by Fenton reaction.