Elucidating the characteristic pleasant aroma profile and underlying molecular sensory mechanisms in vine tea (Ampelopsis grossedentata) cells: a novel supplementary resource for substitute tea.

Vine tea (Ampelopsis grossedentata), a traditional Chinese substitute tea, possesses various notable bioactivities. However, its market scalability is constrained by limited cultivation area and a long growth cycle. Vine tea cell fermentation offers a promising alternative to traditional cultivation for rapidly generating this plant resource. Interestingly, the cultured cells exhibit a distinctive pleasant fruity and floral aroma, a trait absent in their intact plant. To further develop and utilize this novel resource, this study investigated the composition and perceptual mechanisms of the pleasant aroma in vine tea cells. Firstly, fermentation kinetics analysis suggested that vine tea cells grew rapidly, achieving a maximum specific growth rate of 0.44/day. Secondly, comprehensive two-dimensional gas chromatography-mass spectrometry (GC × GC-MS) analysis identified 203 volatiles in the cells, including alcohols, aldehydes, organic acids, esters, ketones, and hydrocarbons. Among them, 72 bioactive volatiles were predicted via network pharmacology to interact with 25 pleasure-released targets. Molecular docking simulations further demonstrated stable binding interactions between these compounds and both pleasure-related and olfactory targets. Meanwhile, quantum chemical calculations indicated that the electronic properties of representative volatiles (e.g., 2-phenylethanol, ethyl benzoate, and methyl benzoate) favored their stable binding with target proteins. Finally, reconstitution experiments using standard compounds confirmed these representative volatiles as pleasant aroma compounds. Therefore, the diversity of volatiles in vine tea cells and their potential interactions with pleasure-related and olfactory targets collectively contribute to the cells' distinctive pleasant aroma. These findings offer theoretical basis for utilizing the cells as a novel supplementary resource to produce high-quality vine tea products.