A DNA microarray for the authentication of toxic traditional Chinese medicinal plants

A silicon-based DNA microarray was designed and fabricated for the identification of toxic traditional Chinese medicinal plants. Species-specific oligonucleoticle probes were derived from the 5S ribosomal RNA gene of Aconitum carmichaeli, A. kusnezoffi, Alocasia macrorrhiza, Croton tiglium, Datura inoxia, D. metel, D. tatula, Dysosma pleiantha, Dy. versipellis, Euphorbia kansui, Hyoscyamus niger, Pinellia cordato, P. pedatisecta, A ternata, Rhododendron molle, Strychnos nux-vomica, Typhonium divaricatum and T. giganteum and the leucine transfer RNA gene of Aconitum pendulum and Stellera chamaejasme. The probes were immobilized via dithiol linkage on a silicon chip. Genomic target sequences were amplified and fluorescently labeled by asymmetric polymerase chain reaction. Multiple toxic plant species were identified by parallel genotyping. Chip-based authentication of medicinal plants may be useful as inexpensive and rapid tool for quality control and safety monitoring of herbal pharmaceuticals and neutraceuticals.