Differentiation of cultivation sources of Ganoderma lucidum by NMR-based metabolomics approach.

ABSTRACT

INTRODUCTION: Ganoderma lucidum is a widely used and high-value medicinal natural product. Correct identification of its cultivation source is important for proper quality assurance, but is so far mostly dependent on subjective morphological examinations. OBJECTIVE: To develop an efficient way of discriminating the cultivation sources of Ganoderma lucidum, particularly those from Korea and China, the two major sources of the mushroom using NMR-based metabolomic differentiation. METHODOLOGY: Ganoderma lucidum samples were collected from Korea (26 samples) and China (20 samples), and their NMR spectra were obtained. The raw data were processed, and analysed using multivariate statistical analysis. RESULTS: Although conventional principal component analysis showed some overlaps, orthogonal projections to latent structure discriminant analysis (OPLS-DA) provided clean distinction between samples from the two countries. Contributing signals were also identified using S-plot, and further verified with independent t-test. Final validation of the model was obtained using prediction test of the unknowns, where the model predicted all of the 14 test samples correctly. Distinction between the cultivation sources within China was also established. CONCLUSION: The easiness and transferability of our NMR-based approach should contribute to addressing an important aspect of quality control process of Ganoderma lucidum. We believe the method can be easily applied to other herbal medical products.