中文摘要：

以不同溶剂和方法对核桃叶进行了抗植物病毒物质的提取和活性测定。结果表明：提取物的抗病毒活性因提取溶剂和提取方法的不同而异。以体积分数95％乙醇为提取溶剂，冷浸提取物在质量浓度10g／L时，对烟草花叶病毒（TMV）的抑制率最高，为100％。采用冷浸提取时，核桃叶中抗TMV活性物质提取的优化条件是：以体积分数95％乙醇为提取溶剂，料液比1：10（g：mL），提取18h，得率21．42％。质量浓度5g／L的提取物对TMV侵染心叶烟的抑制率为100％。该提取物的乙酸乙酯萃取物经多次层析分离和纯化得到黄酮类化合物A，质量浓度0．5g／L的化合物A对TMV侵染心叶烟的抑制率达85．55％，说明化合物A是乙酸乙酯萃取物中的主要抗病毒活性成分之一。

英文摘要：

Antiviral substances of walnut （Juglans regia L. ） leaves were extracted by different solvents and methods, and their antiviral activities were determined. The results showed that antiviral activity is dissimilar based on extracts from walnut leaves with different solvent and methods. For cold-leached extract with 95 % ethanol, when concentration inoculated is 10 g/L, inhibition rate on tobacco mosaic virus（TMV） of the extract was the best, 100 % ; optimum extraction condition of this extract is： 95 % ethanol as solvent, ratio of material to solvent 1 ： 10, soaking time 18 h, extraction rate 21.42 %. The inhibition rate of the extract on TMV infecting Nicotiana glutinosa is 100 % when concentration inoculated is 5 g/L. Besides,an antiviral flavonoid A was isolated from ethyl acetate extract through column chromatography, thin layer chromatography and recrystallization. When its concentration inoculated is 0.5 g/L, inhibition rate of this compound on TMV infecting N. glutinosa is 85.55 %. The result indicated that compound A is one of the main antiviral components in ethyl acetate extract.