Objectives: Plant extracellular vesicles (EVs) mediate intercellular communication and carry tissue-specific metabolites, yet tissue-resolved EV metabolomics in non-model medicinal plants remains poorly explored. Hibiscus syriacus is a valuable medicinal and ornamental species rich in bioactive compounds, but the metabolic profiles of flower- and leaf-derived EVs are unknown. This study aimed to characterize tissue-specific EV metabolomes of H. syriacus and reveal their functional implications. Methods: EVs were isolated from flowers (MJH) and leaves (MJY) of H. syriacus and verified by TEM and DLS. Untargeted LC-MS/MS metabolomics was applied to profile EV metabolites. Multivariate statistics (PCA, OPLS-DA), differential metabolite screening (VIP > 1, p < 0.05), and KEGG pathway enrichment were performed. Results: MJH- and MJY-EVs exhibited typical EV morphology and high purity. In total, 3338 metabolites were identified, dominated by lipids (29.43%). Clear metabolic separation was observed between MJH- and MJY-EVs. Thirty-nine differential metabolites were identified: 31 upregulated in MJH-EVs (lipids, pentadecanoic acid) and eight in MJY-EVs (nucleotides, secondary metabolites). Glycerophospholipid metabolism was the most enriched pathway in MJH-EVs, while MJY-EVs were linked to energy and defensive metabolism. Conclusions: H. syriacus EVs display strong tissue-specific metabolic signatures. Leaf EVs prioritize lipid metabolism for photosynthetic function and stress tolerance, while flower EVs accumulate secondary and energy-related metabolites for reproduction and defense. These findings advance plant EV biology and support potential applications of H. syriacus EVs in cosmetics and agriculture.
Hu et al. (Tue,) studied this question.