苍耳子药材及其混伪品ITS2序列鉴定研究

摘要

Objective: To identify Xanthii Fructus and secure its quality and safety in medication. Methods: Total ge-nomic DNA was extracted from Xanthii Fructus and its adulterants. ITS2 sequences were amplified, and purified PCR products were sequenced. Sequence assembly and consensus sequence generation were performed using the CodonCode Aligner V 4.2. The Kimura 2-Parameter (K2P) distances were calculated using MEGA 5.0. The neigh-bor-joining (NJ) phylogenetic trees were constructed. Results: The intraspecific genetic distances of Xanthii Fructus were 0. The interspecific genetic distances between Xanthii Fructus and its adulterants were ranged from 0.009 to 0.542. The NJ tree showed that Xanthii Fructus could differ from its adulterants obviously. Conclusion: ITS2 can be used to identify Xanthii Fructus from its adulterants effectively, and our study further confirmed the effectiveness of ITS2 to identify traditional Chinese medicinal materials.%目的：应用 ITS2序列快速并准确地鉴定中药材苍耳子，为其药材质量、用药安全提供保障。方法：提取苍耳子药材及其混伪品的基因组DNA、扩增 ITS2序列并测序，采用软件CodonCode Aligner V 4.2对测序峰图进行校对拼接，并对峰图进行质量控制。应用MEGA 5.0软件计算种内种间 Kimura 2-parameter （K2P）遗传距离,构建邻接（NJ）系统聚类树。结果：苍耳子药材基原物种种内 K2P 遗传距离为0，药材基原物种与其他混伪品的 K2P遗传距离分布于0.009~0.542；NJ树结果显示苍耳子药材与其混伪品均可明显区分。结论：ITS2序列适用于中药材苍耳子及其混伪品鉴别，进一步验证了DNA条形码技术鉴定中药材的有效性。