摘要
目的利用ITS2条形码鉴别两面针药材及其混伪品,为两面针药材鉴定提供新方法。方法采用PCR法扩增ITS2(转录第二间隔区)序列,双向测序后运用CodonCode Aligner、MEGA软件进行数据处理,构建系统聚类树(NJ树)。结果两面针药材及其混伪品基因组DNA降解明显,但不影响ITS2条形码的PCR扩增和测序,ITS2条形码序列分析表明种内与种间遗传距离具有较大差异,基于ITS2条形码构建NJ树可鉴别两面针药材及其混伪品。结论 ITS2条形码适用于两面针药材及其混伪品的鉴别,为两面针药材快速、准确鉴定提供新方法;为两面针基原研究提供重要的分子鉴定证据;同时为DNA条形码技术应用于其他根、茎类中药材的鉴定提供了示范作用。
Objective ITS2 barcoding was used to discriminate Zanthoxyli Radix and its adulterants to ensure the quality and clinical safety of this Chinese materia medica. Methods The internal transcribed spacer 2 （ITS2） regions were amplified and sequenced bi-directionally. Then the obtained sequences were assembled using the CodonCode Aligner. The ITS2 regions were obtained using the hidden Markov model （HMM）-based annotation methods. The genetic distances of the ITS2 regions were computed in accordance with the kimura 2-parameter （K2P） model and Neighbor-joining （NJ） phylogenetic trees were constructed using MEGA5.0. Results The length of ITS2 sequences of the plants in Zanthoxyli Radix and its adulterants were between 224 and 227 bp. Their mean intraspecific genetic distance （K2P distance） was lower than their mean interspecific genetic distance with the adulterants. The NJ trees showed that the roots of Zanthoxyli Radix could be easily distinguished from its adulterants. Conclusion ITS2 barcode could be used to identify the roots of Zanthoxyli Radix and its adulterants effectively, and provide the important molecular evidence for the authentication of germplasm resources.
出处
《中草药》
CAS
CSCD
北大核心
2013年第15期2150-2154,共5页
Chinese Traditional and Herbal Drugs
基金
广东省教育部产学研结合项目(2009B090300202)
