Panax notoginseng , a traditional Chinese medicinal herb, holds significant historical and clinical value due to its ability to promote blood circulation, alleviate blood stasis, and provide neuroprotective effects. The primary bioactive constituents of this herb are P. notoginseng saponins (PNS). However, the mechanisms underlying the biosynthesis and regulation of PNS remain inadequately understood. The contents of notoginsenoside R1, ginsenosides Rg1, Re, Rb1, and Rd in P. notoginseng roots were determined using high-performance liquid chromatography. The protein composition of P. notoginseng roots was digested and labeled by tandem mass tags, and high pH reverse phase separation, analyzed using low pH nano high performance liquid chromatography-mass spectrometry (pH nano-HPLC-MS/MS) analysis system. Key protein data and regulatory pathways in the roots of P. notoginseng were analyzed to identify the essential enzymes and their corresponding genes involved in ginsenoside synthesis. A total of 7,578 proteins were identified, among which 252 differentially expressed proteins (DEPs) were characterized. Specifically, 155 were found to be downregulated, while 93 were upregulated in the comparison of high to low (H/L) ginsenoside content. The DEPs were primarily associated with biological processes, molecular functions, and cellular components, as classified by Gene Ontology. Additionally, Kyoto encyclopedia of genes and genomes pathway enrichment analysis revealed a significant involvement of the ribosomal pathway. Notably, 19 enzymes identified among the DEPs are linked to ginsenoside biosynthesis. This study analyzed the differences in the content of five major ginsenosides in P. notoginseng roots and identified the key proteins (enzymes) involved in regulating ginsenoside synthesis. The findings highlight the regulatory roles of the cytochrome P450 ( CYP450 ) and UDP-glycosyltransferase ( UGT ) enzyme families in the biosynthetic pathways of secondary metabolites, providing valuable insights into the biosynthesis of the active medicinal components in P. notoginseng . • The triterpenoid saponins are the primary bioactive compounds of Panax notoginseng. • Proteomics reveals the biosynthetic pathway of triterpenoid saponins in Panax notoginseng. • Candidate cytochrome P450 is involved in ginsenoside synthesis in Panax notoginseng.
Liang et al. (2026) studied this question.