石斛干品基因组DNA的提取与RAPD分析

市场中药干品的药性差异一直是影响中药标准化的瓶颈，而检测技术相对落后是导致这一现象的主要原因。DNA分子水平检测的困难是药材干品的基因组DNA难以提取。本文以铁皮石斛(Dendrobium candidum)干茎为材料，采用了四种方法从干品石斛中提取基因组DNA。结果表明，采用改良的CTAB法可从石斛干品尤其是干茎皮中提取质量较高的基因组DNA，其分子量大于23kb，以此DNA为模板进行不同引物的PCR扩增可获得清晰的RAPD条带。该研究初步建立了石斛干品合适的RAPD技术体系。

Genomic DNA Extraction and RAPD Analysis from Aired-dried Stem of Dendrobium candidum

The pharmic difference of air-dried Chinese herbs on the market is the bottleneck for Chinese medicine standardization, which arises from relative lag assay. The genomic assay based on DNA is blocked by the difficulty of genomic DNA extraction from air-dried Chinese herbs materials. In this study, four different methods were used for genomic DNA extraction from air-dried Dendrobium candidum stem respectively. The most effective method is improved CTAB protocol, which is also applied for extraction of the genomic DNA from air-dried D. candidum stem coat. The high quality DNA was shown up to 23 kb on agrose gel electrophoresis obviously from air-dried D. candidum stem coat. Using this genomic DNA as a template by PCR with various random primers, the several RAPD bands were displayed clearly. The establishmet of fast extraction of high-quality genomic DNA from D. candidum and RAPD reactive condition will facilitate the standard assay for precious Chinese medicine D. candidum.