油浴模拟砂炒过程中印乌碱的结构转化途径及转化产物毒性研究

Study on structural transformation pathway of indaconitine in stir-frying with sand process and toxicity of its processing products

目的研究印乌碱在砂炒(油浴模拟)过程中的结构转化途径并比较印乌碱及其转化产物的毒性。方法采用HPLC法筛选出印乌碱发生结构转化的温度和时间参数;通过柱色谱法和NMR、MS等波谱法,分离、鉴定出印乌碱的砂炒转化产物;采用心脏毒性实验比较原型成分印乌碱及其转化产物的毒性。结果通过比较不同炮制温度、时间样品的HPLC色谱图,筛选出印乌碱在160~180℃,加热10~30 min时发生结构转化;分离、鉴定出砂炒产物mithaconitine;II导联心电图(electrocardiogram,ECG)表明,0.06mg/kg印乌碱可引起正常大鼠出现室性早搏(ventricularprematurebeat,VPB)、室性心动过速(ventricular tachyrhythmia,VT)等心律失常现象;mithaconitine在该剂量下未引起大鼠典型的心律失常ECG。结论砂炒过程中,印乌碱的C-8位脱去乙酰基,转化为14-benzoylpseudaconine;接着,14-benzoylpseudaconine的C-8位、C-15位发生脱水反应转化为mithaconitine,达到砂炒减毒的目的。

Objective To study the structural transformation pathway of indaconitine in stir-frying with sand process and compare the toxicity of indaconitine with its processing products.Methods Using high performance liquid chromatography to screen out the temperature and time parameters of the structural transformation of indaconitine.The processing products were separated by column chromatography and identified by NMR and MS.The cardiotoxicity test was chosen to compare the toxicity of indaconitine with its processing products.Results Indaconitine was converted into mithaconitine when it was heated at 160—180℃for 10—30 min.With a dose of 0.06 mg/kg,indaconitine could induce ventricular arrhythmia in rats,such as ventricular premature beat,ventricular tachycardia.However,mithaconitine had no arrhythmogenic effect at the same dosage.Conclusion The structural transformation pathway of indaconitine has been defined:deacetylating at C-8 position,generating 14-benzoylpseudaconine,and converting benzoylpseudaconine into mithaconitine by dehydration reaction at C-8 and C-15 position.Compared with indaconitine,the toxicity of mithaconitine was reduced.