中华蟾蜍DNA条形码鉴定

Identification of Bufo gargarizans and Its Adulterants by DNA Barcoding Technique

目的:通过DNA条形码研究鉴别中药材中华蟾蜍Bufo gargarizans Cantor及其混伪品的可行性。方法:从Gen Bank下载了6种蟾蜍属Bufo、2种林蛙属Rana、1种侧褶蛙属Pelophylax和1种小鲵属Hynobius的COI线粒体基因DNA序列。用Clustal X 1.81和Bio Edit软件分别对序列进行比对和编辑。利用MEGA 4.0软件按照Kimura双参数法计算种内和种间的遗传距离。用贝叶斯法和简约法构建系统发育树对中华蟾蜍进行鉴定。结果:构建的系统发育树表明,中华蟾蜍的所有样本聚类为一个单系,能很好地与其他混伪品区分。结论:COI条形码DNA序列能够对中药中华蟾蜍进行准确鉴定。

Objective： To study the feasibility of using DNA barcoding technique to identify Bufo gargarizans and its adulterants based on COI gene. Methods： Sequences of partial mitochondfial DNA from cytochrome oxidase subunit I （COI） gene of 6 species from Bufo, 2 species from Rana, 1 species from Pelophylax, and 1 species from Hynobius were downloaded from the GenBank data library. The COl sequences were aligned and edited using ClustalX 1.81 and BioEdit 7. 0. 9.0 software, respectively. The interspecific and intraspecific genetic distances of different sequences were calculated by Kimura double parameter method using software MEGA 4. 0. Based on all the aligned and edited COI sequences, the phylogenetic analyses were conducted using Bayesian inference（BI） and maximum parsimony（MP） to identify B. gargarizans and adulterant. Results： COI sequence haplotypes of different samples of B. gargarizans were gathered together, formed its own monophyly, and distinguished from its adulterants by BI and MP trees. Conclusion： The COI sequence is ideal DNA barcode to identify B. gargarizans and its adulterants correctly.