Reviewing the Mechanisms of the Interaction of Characteristic Aroma Compounds of Longjing Tea with S-curve, Molecular Docking, and Molecular Dynamics Simulation: With a Focus on (+)-(1<i>R</i>,2<i>S</i>)-Methyl Epijasmonate and β-Ionone as Examples

The <i>S</i>-curve method, molecular docking, and molecular dynamics simulation (MDS) were used to explore the interaction between the aroma compounds of Longjing tea and receptors. The ratio of experimental and theoretical threshold (<i>D</i>) values for (+)-(1<i>R</i>,2<i>S</i>)-methyl epijasmonate and β-ionone was 0.46, indicating a synergistic effect between them. Similarly, synergistic interactions occurred between (<i>R</i>)-(+)-γ-nonanolactone and (<i>R</i>)-(+)-γ-decalactone (<i>D</i> = 0.42), 3-methylbutanal and 2-ethyl-3,5-dimethylpyrazine (<i>D</i> = 0.43). Molecular docking indicates significant changes in the affinity and stability between the binary system and individual compounds with receptors (OR52D1 and OR1A1). Through MDS analysis, it was found that the hydrophobic residues in OR52D1-β-ionone changed from Leu203, Val205, Ala206, Ala258, and Met210 to Tyr111, Ala112, Met210, Ala209, and Ala206 after addition of (+)-(1<i>R</i>,2<i>S</i>)-methyl epijasmonate. Hydrophobic interactions play an integral and important role in the formation of a stable ternary architecture between (+)-(1<i>R</i>,2<i>S</i>)-methyl epijasmonate-β-ionone and OR52D1. By calculating the binding energy of MMGBSA, it was found that the addition of (+)-(1<i>R</i>,2<i>S</i>)-methyl epijasmonate reduced the energy of the binary system from -53.58 to -58.48 kcal/mol, indicating better stability of the new system. The molecular mechanisms of interactions between the characteristic compounds of Longjing tea were revealed, thus providing theoretical support for improving the flavor of Longjing tea.