2018 Volume 87 Issue 1 Pages 76-82
Aconite(Aconitum japonicum Thunberg) is a perennial Ranunculaceae species, which contains aconitine alkaloids especially in its tuberous root, and is used as a medicinal crop. The ingredient content is important as a material for Chinese medicine. In this study, we analyzed the relationship between the size of the tuberous root and the percentage ingredient contents. The percentage total alkaloid content of the tuberous root decreased with the increase in dry weight of the tuberous root and stayed constant at a dry weight exceeding 35g. In the field experiments, total alkaloid, mesaconitine, hypaconitine and aconitine contents were determined in the tuberous roots according to size: large (>30 mm), medium (>20 mm) and small (<20 mm). The tuberous root size showed a significantly negative correlation with the percentage ingredient content of the tuberous root. Thus, it is concluded that the cultivation technology to produce a larger tuberous root is effective to control the percentage ingredient content. However, cultivation conditions and their interaction with tuberous root size also had significant effects on the percentage ingredient content. In the tuberous root, we found that the percentage aconitine alkaloid content was high in both apical and basal parts, especially in the apical part with buds. This may be why the percentage content of ingredients is lower in larger tuberous roots. When the ingredient content needs to be analyzed for a large number of samples with different genotypes or under different cultivation conditions, each tuberous root should be divided longitudinally so each sample has both apical and basal parts.
