A holistic visualization for quality of Chinese materia medica: Structural and metabolic visualization by magnetic resonance imaging

Abstract

The quality of Chinese materia medica (CMM) is a challenging and focused topic in the modernization of traditional Chinese medicine (TCM). A profound comprehension of the morphology, structure, active constituents, and dynamic changes during the whole process of CMM growth is essential, which needs highly precise contemporary techniques for in-depth elucidation. Magnetic resonance imaging (MRI) is a cutting-edge tool integrating the benefits of both nuclear magnetic resonance (NMR) spectroscopy and imaging technology. With real-time, non-destructive, and in situ detection capabilities, MRI has been previously used for monitoring internal and external structures of plants alongside compounds during physiological processes in vivo. Here, factors involved in the holistic quality evaluation of CMMs were investigated. Given the applications of MRI in various plants, several representative CMMs were used as examples to demonstrate a methodology of quality visualization by MRI, embodying holistically monitoring the real-time macroscopic morphology, mesoscopic structure, and microscopic metabolites non-destructively in situ. Taken together, the review not only presents a pioneering application mode for utilizing MRI for CMM quality visualization but also holds promise for advancing the quality control and evaluation of CMMs.

Keywords: Chinese materia medica; Magnetic resonance imaging; Quality; Structure and metabolites; Visualization.

Graphical abstract

Fig. 1

The holistic visualization of Dendrobium huoshanense (D. huoshanense). (A) The high-resolution three dimensions projection view of the whole plant D. huoshanense by magnetic resonance imaging (MRI). (B, C) Metabolic profiling in stem (red) (B) and root (blue) (C) of D. huoshanense by magnetic resonance spectroscopy.

Fig. 2

The simultaneous visualization of structure and metabolite profiles of Dendrobium huoshanense (D. huoshanense). (A) Three dimensions flash magnetic resonance imaging (MRI) with 40-μm isotropic ultra-high resolutions. The arrows point to tiny bubbles inside the roots. (B) Internal images of a very dry capsule of D. huoshanense acquired by MRI in axial slices and coronal slices. (C) Chemical structure of differential chemical constituents in stem and root of D. huoshanense. (D) Distribution of chemical constituents in roots of D. huoshanense and its similar species Dendrobiummoniliforme (D.moniliforme).

Fig. 3

Differences of Salvia miltiorrhiza during sweating processing revealed by magnetic resonance imaging (MRI). (A, B) Axial (A) and sagittal (B) images of the root before sweating processing. (C, D) Axial (C) and sagittal (D) images of the root after sweating processing.