DOI: https://doi.org/10.55373/mjchem.v27i6.147

Keywords: Melicope pteleifolia; essential oil; chemical composition; enzyme inhibition; molecular docking

Abstract

Essential oil (EO) from Melicope pteleifolia leaf samples, collected from two geographically and climatically distinct regions in Vietnam, namely Quang Tri and Lam Dong provinces, exhibited different compositions and yields of 0.12 % and 0.14 % (EO1 and EO2, respectively). Gas Chromatography-Mass Spectrometry (GC-MS) analysis identified 54 compounds (94.99 %) in EO1 and 43 compounds (88.31 %) in EO2, with significant regional differences in major constituents. EO1 was rich in α-pinene (11.99 %), β-(Z)-ocimene (5.58 %), β-caryophyllene (11.15 %), and aromadendrene (6.86 %), while EO2 contained trans-α-bergamotene (22.2 %), δ-cadinene (10.88 %), and humulene epoxide II (7.47 %). Both oils demonstrated α-amylase inhibitory activity, with IC₅₀ values of 72.60 ± 2.00 μg/mL (EO1) and 73.63 ± 1.84 μg/mL (EO2), surpassing acarbose (IC₅₀ = 121.05 ± 3.96 μg/mL). However, tyrosinase inhibition activity was weak, failing to reach 50 % inhibition. Molecular docking confirmed humulene epoxide II as a key α-amylase inhibitor, with a binding energy of -8.038 kcal/mol, interacting with crucial residues. These findings highlight the potential of M. pteleifolia EO for antidiabetic applications, warranting further investigation.