Laekeman G M, Mertens J, Totté J, Bult H, Vlietinck A J, Herman A G
J Nat Prod. 1983 Mar-Apr;46(2):161-9. doi: 10.1021/np50026a003.
Vernolepin, a sesquiterpene lactone, was isolated from the dried fruit of Vernonia amygdalina Del. The different steps used during the extraction were: continuous extraction with chloroform, partition of the chloroform-extract between pertroleum ether and 10% aqueous methanol, column chromatography of the methanol extract, isolation of the active fractions by pharmacological and chemical characterization. Vernolepine was obtained as colorless prisms and identified by melting point, uv, ir, 1H nmr, optical rotation, and mass spectrometry. The total content of the dried fruit was 0.09% vernolepin. The first pharmacological characterization of vernolepin revealed: (1) a competitive antagonism against histamine in guinea pig ileum (pA2 = 5.61; 15 min incubation); (2) a biphasic enhancement/inhibition of coaxial stimulation of guinea pig ileum; (3) an antiaggregating and disaggregating activity against rabbit platelet aggregation induced by arachidonic acid (1 X 10(-4) g/ml; 3.3 X 10(-4)M) or ADP (4 X 10(-6) g/ml; 1 X 10(-5)M) without inhibition of cyclo-oxygenase or lipoxygenase. All these reactions were time dependent and occurred at concentrations of 5 X 10(-6) to 1 X 10(-5) g/ml vernolepin (1.8 to 3.5 X 10(-5)M).
斑鸠菊苦素是一种倍半萜内酯，从扁桃斑鸠菊的干燥果实中分离得到。提取过程中采用的不同步骤包括：用氯仿连续萃取，将氯仿提取物在石油醚和10%甲醇水溶液之间进行分配，对甲醇提取物进行柱色谱分析，通过药理和化学表征分离活性组分。斑鸠菊苦素呈无色棱柱体，通过熔点、紫外光谱、红外光谱、核磁共振氢谱、旋光度和质谱进行鉴定。干燥果实中斑鸠菊苦素的总含量为0.09%。斑鸠菊苦素的首次药理表征显示：（1）对豚鼠回肠中的组胺具有竞争性拮抗作用（pA2 = 5.61；孵育15分钟）；（2）对豚鼠回肠的同轴刺激具有双相增强/抑制作用；（3）对花生四烯酸（1×10(-4) g/ml；3.3×10(-4)M）或ADP（4×10(-6) g/ml；1×10(-5)M）诱导的兔血小板聚集具有抗聚集和解聚活性，且不抑制环氧化酶或脂氧合酶。所有这些反应均具有时间依赖性，且在斑鸠菊苦素浓度为5×10(-6)至1×10(-5) g/ml（1.8至3.5×10(-5)M）时发生。
