Identification of toxic plants from poisonous samples using massively parallel sequencing

Some toxic plants have strong morphological similarities to edible wild plants. Therefore, poisoning often occurs due to the accidental ingestion. It is important to identify the poisonous plant among the mixture of edible plants, even if the samples have been digested. In this study, we developed a method for genus or species identification in mixed samples using massively parallel sequencing (MPS). We developed and optimized a MPS analysis method for trnL and rbcL region used in plant species identification. We analyzed mixed samples, cooked materials, and simulated gastric contents. Initially, DNA from poisonous plants (Veratrum album and Colchicum autumnale) and edible plants (H. sieboldiana) was mixed in various ratios and analyzed by MPS. Next, we prepared cooked materials and simulated gastric contents of V. album, C. autumnale, and H. sieboldiana and analyzed by MPS. We were able to detect both poisonous plant DNA and edible plant DNA mixed in equal amounts. In cooked or simulated gastric acid contents, poisonous plants were also detected. It suggested that our method can also be used to identify sample species from cooked materials and simulated gastric contents. These results indicate that MPS techniques are useful for the forensic analysis of plant materials.