Widely Targeted Metabolomic Analysis of Metabolic Differences Among Various Organs of Clematis huchouensis from the Huzhou Production Region
Background/Objectives: Clematis huchouensis Tamura, a genuine medicinal herb endemic to Huzhou, Zhejiang Province. However, its secondary metabolic profile and organ-specific distribution of bioactive constituents remain largely uncharacterized. This study aims to systematically characterize the metabolic profile of its roots, stems, and leaves, and to elucidate organ-specific accumulation patterns of pharmacologically relevant constituents, thereby providing a scientific basis for resource evaluation and quality control of this regional germplasm. Methods: A widely targeted metabolomics approach was employed to profile metabolites in the roots, stems, and leaves of C. huchouensis. Comprehensive annotation and relative quantification were performed using ultra-performance liquid chromatography–tandem mass spectrometry (UPLC-MS/MS) combined with database matching. Cluster analysis and pathway enrichment were conducted to compare metabolic profiles across organs. Results: A total of 1561 metabolites were identified, exhibiting distinct organ-specific accumulation patterns. Flavonoids, alkaloids, and most phenolic acids were predominantly enriched in the aerial parts, whereas the roots accumulated high levels of glutathione and its related peptides, reflecting their significant antioxidant activity. Amino acids displayed complementary tissue-specific distribution, with peptides enriched in leaves and sulfur-containing amino acids such as L-methionine in stems. Organ-specific metabolic differences were significantly associated with pathways including flavonoid biosynthesis and linoleic acid metabolism. Notably, numerous pharmacologically active compounds, such as hispidulin, diosmetin, trigonelline, colchicoside, and oleanolic acid-3-O-xylosyl(1→3)glucuronide—exhibited marked tissue-selective accumulation. Conclusions: This first metabolomic study of C. huchouensis reveals organ-specific accumulation of bioactive compounds, providing a metabolic foundation for its quality control and rational utilization.