Insecticidal activity and active components of alcohol extract from Juglans mandshurica Maxim leaves
核桃楸叶乙醇提取物杀虫活性及活性成分

The insecticidal active components in Juglans mandshurica Maxim leaves were extracted by conventional method. The alcohol extract and its chloroform-extraction phase showed insecticidal activities in contact toxicity and stomach toxicity against Lymantria dispar L. and Mamestra brassicae L. larvae. When the concentration of the extract was above 10 g x L(-1), the corrected mortality was higher than 50% 5 days after applying the extract. Alcohol extract had higher insecticidal activities than its chloroform-extraction phase. The GC-MS analysis on the active components in the chloroform-extraction phase showed that the main component was juglone (5-hydroxy-1,4-naphthalenedione), and the others were 2,2'-methylenebis-6-(1,1-dimethylethyl)-4-methyl-diphenol and 2-methoxy-4-vinylphenol.