目的 建立南大青叶马蓝Baphicacanthus cusia的分子鉴别方法。方法 分析36批马蓝及其混伪品的ITS2和psbA-trnH基因序列信息，根据关键差异位点建立相应的聚合酶链式反应法-限制性片段长度多态性分析（polymerase chain reaction-restriction fragment length polymorphism，PCR-RFLP）鉴别方法，并考察该方法的专属性和耐用性。结果 马蓝的psbA-trnH基因序列与其混伪品的无明显位点差异，ITS2基因序列具有明显的种间差异，其中1个关键差异位点可被限制性内切酶Sma I识别和酶切，以此建立的PCR-RFLP鉴别方法符合《中国药典》2020年版四部中专属性和耐用性的要求。结论 建立了有效鉴别南大青叶的PCR-RFLP方法，且该方法适用于基原物种为马蓝的其他中药材鉴别。

Objective To establish a molecular identification method for leaves of Baphicacanthus cusia. Method The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) identification method was established on sequencing the ITS2 and psbA-trnH with DNA bacording technique from ChP. 2020 Volume Ⅳ, analyzing the variation site of 36 batches leaves of B. cusia and its adulterants, and verifying the specificity and durability. Result There was significant interspecific difference in ITS2 and no available variation site in psbA-trnH of B. cusia and its adulterants. The PCR-RFLP method with recognizing the critical site in ITS2 and digesting the amplicifition product of B. cusia by restriction enzyme Sma I was established and verified. Conclusion The PCR-RFLP method based on ITS2 DNA barcode can effectively identify B. cusia and its adulterants.

R282.12

广州市科技计划项目（20212210005）；广州市市场监督管理局科技项目