Organ-Resolved Metabolomics of Cibotium barometz Reveals Rhizome-Specific Terpenoid Lactones and Phenolic-Rich Non-Officinal Organs

Background: Cibotium barometz (L.) J. Sm. is a medicinal fern whose rhizome is the sole officinal part, while roots, stems, leaves and young shoots are discarded as agricultural residues. The chemical rationale for this restriction, and the value of the discarded organs, remain undefined. Materials and methods: Here, untargeted LC–MS/MS metabolomics (UHPLC–Orbitrap) of methanol/acetonitrile/water extracts was applied to five organs of C. barometz (three pooled biological replicates per organ), annotating 2765 polar-to-moderately-polar metabolites. Results: Organ identity dominated the metabolic architecture of the sampled population: the first two principal components separated all five organs, with leaf and root as the two mutually opposed metabolic extremes and stem, young shoot and rhizome forming a contiguous module. Exploratory pairwise OPLS-DA combined with FDR-controlled univariate criteria yielded 193–1223 differentially accumulated metabolites per comparison, and tissue-specificity analysis assigned 2031 metabolites (73.45%) predominantly to a single organ. Discussion: Metabolite accumulation patterns along the phenylpropanoid–flavonoid pathway was spatially partitioned, with flavan-3-ols and isoflavones accumulating in root, flavone/flavonol glycosides in leaf and predominantly hydroxycinnamic acids in rhizome and young shoot. Of 22 previously reported or candidate quality control constituents, putatively annotated terpenoid lactones were detected almost exclusively in the rhizome, whereas several phenolics showed markedly higher relative abundance in root or leaf. Conclusions: These relative-abundance data indicate that the non-officinal organs are chemically complementary potential resources; absolute quantification, bioactivity and safety evaluation are prerequisites before any medicinal valorisation.