Spatial metabolomics reveals potential biomarkers for red secretory
cavities in Atractylodes lancea natural accessions
Abstract
Atractylodes lancea, known as Cangzhu in Chinese ,
has been widely used in the traditional Chinese medicine (TCM). The
colour of secretory cavity (SC) at Atractylodis Rhizoma (AR) differs
greatly among geographic origins and cinnabar-like red SCs of AR is
considered of high quality in TCM. However, chemical basis underlying
this colour variation across natural accessions and within plant tissues
are largely unknown, impeding implications of efficacy of cinnabar-like
spots for Cangzhu in TCM. Here, we carried out laser capture
microdissection (LCM) based metabolomics on three A. lancea
natural accessions with distinct AR colour patterns. Multivariate
statistics across various SC types identified three polyacetylenes
significantly associated with the red SCs of AR. Mass spectrometry
imaging (MSI) further indicated that they are likely the causal
compounds underlying the cinnabar-like colour of SCs in A.
lancea. We thus provide a clear example of using spatial metabolomics
to reveal key metabolite markers associated with important
pharmaceutical properties by using very limited number of natural
accessions in a non-model plant. It will further guide the elucidation
of biosynthetic pathways for polyacetylenes in herbaceous plant A.
lancea.