采用活性跟踪法,对生栀子(Gardenia)中的杀螨活性成分进行研究。通过对生栀子乙酸乙酯部分的萃取物进行分离和纯化,获得了2个具有较强杀螨作用的化合物Ⅰ和化合物Ⅱ。采用色谱技术鉴定其化学结构分别为京尼平苷和熊果酸。试验结果表明,京尼平苷和熊果酸可能是生栀子中重要的杀螨活性物质。这2种化合物对朱砂叶螨的触杀活性的半致浓度(LC50)值分别为2.69 mg/mL、1.81 mg/mL。并发现当2种试剂的溶液中加入等浓度等体积的KOH溶液后,半致死浓度为0.94 mg/mL和0.95 mg/mL,其杀螨活性大幅度提高。
Using the acaricidal activity to guide the isolation,the compoundsⅠandⅡ,which had the highest toxicity to Tetranychus cinnabarinus,were obtained from the ethyl acetate extracts of Gardenia jasminoides Ellis.The structure of compounds ⅠandⅡ were established as geniposide and ursolic acid by using various chromatographic techniques.The results of acaricidal activity analysis showed that geniposide and ursolic may be the principal acaricidal substance in the extracts ofGardenia jasminoidesEllis.The mean lethal concentrations(LC50) of geniposide and ursolic acid for contact toxicity were detected as 2.69 mg/mL and 1.81 mg/mL.And their contact toxicity were significantly improved when join with KOH;the mean lethal concentrations(LC50) for contact toxicity were 0.94 mg/mL and 0.95 mg/mL.