Chemical profiling and in silico target prediction of Lippia alba leaf essential oil supported by in vitro...

Lippia alba (Mill.) N. E. Brown, an aromatic shrub belongs to the Verbenaceae family widely applied in traditional remedies and pharmaceutical applications. The current study aims to analyse the chemical composition of L. alba leaf essential oil (LALEO) using GC-MS and to assess its in vitro biological activities, including anti-oxidant, anti-inflammatory, acetylcholinesterase inhibitory, and tyrosinase inhibitory effects along with in silico molecular docking against Cox 2(Cyclooxygenase-2) and human acetylcholinesterase (AChE). The LALEO was extracted using Clevenger type apparatus. GC-MS analysis identified 26 chemical compounds, with geranial being the most abundant at 26.21%. ABTS (2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid) and DPPH (2,2-diphenyl-1-picrylhydrazyl) assays of LALEO demonstrated significant antioxidant potency, with IC₅₀ values of 10.71 μg/mL and 15.67 μg/mL, respectively. The trypsin inhibitory assay revealed strong anti-inflammatory activity IC₅₀ = 16.12 μg/mL, while the acetylcholinesterase (AChE) inhibitory assay demonstrated an IC₅₀ value of 10.07 μg/mL. The anti-tyrosinase activity yielded an IC₅₀ value of 11.22 μg/mL, outperforming the standard kojic acid (12.56 μg/mL). In silico docking revealed that among the tested constituents, only cubebol (-7.8 kcal/mol) exhibited a higher calculated binding affinity for hAChE than the standard galantamine (-7.6 kcal/mol), whereas β-myrcene (-6.7 kcal/mol) showed weaker binding affinity, indicating cubebol's targeted potential against neurodegenerative disorders linked to AChE imbalance. For COX-2, caryophyllene (-6.3 kcal/mol)) and cubebol (-6.2 kcal/mol) demonstrated comparable, though slightly lower, binding affinities relative to the standard sodium diclofenac ((-6.4 kcal/mol), highlighting their potential as preliminary computational lead hits for multi-target virtual screening. The present study suggests that LALEO has potential for further research and the development of natural medicines, after having scientific validation.