Flavor and bioactive compound profiling of sea buckthorn leaf tea: Characterization of key bitter constituents and prediction of their anti‐type 2 diabetes activity

BACKGROUND Sea buckthorn leaves possess significant nutritional and medicinal properties but suffer from poor consumer acceptance as a result of their pronounced bitterness and astringency. However, these aversive bitter constituents often correspond to valuable bioactive compounds. The present study aimed to investigate how fermentation modulates the flavor profile of sea buckthorn leaf tea (SBLT) and to explore the potential anti‐diabetic bioactivities of its core bitter components. RESULTS Sensory and chromatographic analyses revealed that fermentation significantly altered the chemical composition of SBLT. Fermentation shifted the aroma from fresh and grassy to a complex profile of roasted, caramel and woody notes. Nineteen key aroma compounds were identified, with 2‐ethyl‐3,5‐dimethylpyrazine and 2‐furylmethanol serving as representative markers. Crucially, fermentation mitigated bitterness and astringency primarily through the hydrolysis of flavonoid glycosides into aglycones. Thirteen core constituents were found to be highly correlated with bitterness, including epicatechin and procyanidin B2. Molecular docking confirmed that these bitter‐tasting molecules exhibit high binding affinities (up to −8.5 kcal mol −1 ) with bitter receptors TAS2R14 and TAS2R39. Network pharmacology further demonstrated that these bitter compounds synergistically target 874 type 2 diabetes mellitus (T2DM)‐related nodes, primarily modulating the phosphoinositide 3‐kinase‐Akt and tumor necrosis factor signaling pathways through core targets such as AKT1, interleukin‐6 and GAPDH. CONCLUSION Fermentation is an effective processing strategy that enhances the sensory quality of SBLT by reducing bitterness and enriching roasted aromas. The multi‐target network analysis underscores that these bitter constituents act as key anti‐inflammatory and glucose‐regulating agents, providing a strong theoretical basis for SBLT as a functional dietary intervention for T2DM.