Metabolic fingerprinting for discrimination of DNA-authenticated Atractylodes plants using ¹H NMR spectroscopy

Identifying different species of the genus Atractylodes which are commonly used in Chinese and Japanese traditional medicine, using chromatographic approaches can be difficult. ¹H NMR metabolic profiling of DNA-authenticated, archived rhizomes of the genus Atractylodes was performed for genetic and chemical evaluation. The ITS region of the nuclear rDNA was sequenced for five species, A. japonica, A. macrocephala, A. lancea, A. chinensis, and A. koreana. Our samples had nucleotide sequences as previously reported, except that part of the A. lancea cultivated in Japan had a type 5, hybrid DNA sequence. Principal component analysis (PCA) using ¹H NMR spectra of extracts with two solvent systems (CD₃OD, CDCl₃) was performed. When CDCl₃ extracts were utilized, the chemometric analysis enabled the identification and classification of Atractylodes species according to their composition of major sesquiterpene compounds. The ¹H NMR spectra using CD₃OD contained confounding sugar peaks. PCA removal of these peaks gave the same result as that obtained using CDCl₃ and allowed species distinction. Such chemometric methods with multivariate analysis of NMR spectra will be useful for the discrimination of plant species, without specifying the index components and quantitative analysis on multi-components.