遺伝子解析による奈良県産キハダの種鑑別

抄録

Phellodendron amurense Ruprecht or Phellodendron chinense Schneider (Rutaceae) is a deciduous tree of the Rutaceae family. Phellodendron bark without the periderm is used as a crude drug. Because the domestically used amount of Phellodendron bark is large, Japan’s self-sufficiency rate is only 1.1%. For this study, DNA sequences of rbcL, trnH-psbA, trnL, trnL-trnF, and ITS regions were found for the leaves of Phellodendron amurense and Phellodendron chinense, Phellodendron bark produced in Nara Prefecture, outside of Nara Prefecture, and in China. After the sequences were compared using BLAST search, a phylogenetic tree was constructed using the neighbor-joining method. Findings from both sequence comparison and phylogenetic analysis showed that all the regions could be differentiated up to the genus Phellodendron. Through interspecific comparison, single nucleotide variants were identified in three regions using the sequence comparison. Two regions were used in the phylogenetic analysis to differentiate P. amurense from P. chinense, thereby confirming that the subject specimens from Nara Prefecture and other prefectures are P. amurense. The combination of sequencing of multiple regions and the phylogenetic analysis of the two regions found in this study proved to be effective for identifying P. amurense.