Specific Polymerase Chain Reaction Molecular Identification of Pheretima aspergillum (E. Perrier) / 广州中医药大学学报

ABSTRACT

Objective To screen out the polymerase chain reaction ( PCR) primers for specifically identifying Pheretima aspergillum (E. Perrier) , so as to establish a rapid and accurate method to identify the origin of Pheretima aspergillum. Methods Four kinds of earthworms recorded in pharmacopoeia and six kinds of their adulterants commonly seen in the market were collected. The 12SrRNA sequences related to earthworm were downloaded from GenBank database. PCR amplification for ten kinds of samples was performed using the universal primers, and then the products were sequenced. According to the differences between the above sequences, three pairs of specific primers in the non-conservative district were designed for identification of Pheretima aspergillum. Results High-specificity PCR amplification for Pheretima aspergillum with 12St/12Stf primer occurred when the annealing temperature was increased to 64℃, and only Pheretima aspergillum had single amplification strip, while no strips were found in the other adulterants under the same condition. The achieved specific primers could be well verified in 15 kinds of medicinal materials of earthworm purchased in the market, which had the same morphological features showed by the traditional identifying method. Conclusion With 12St/12Stf primer as a specific marker, the identifica tion of Pheretima aspergillum is rapid and accurate in related species of Pheretima aspergillum, and avoids the effect of some factors such as integrity of experimental materials and drying process.