Chemical composition and in silico evaluation of Acacia auriculiformis stem bark essential oil for multi-target pesticidal activity

Due to the increasing demand for environment-friendly pesticidal agents, there is growing interest in chemicals from plant origin. The current study aims at the assessment of chemical composition and pesticidal potential of Acacia auriculiformis ( A. auriculiformis ) stem bark essential oil using an integrated in silico approach. Gas chromatography–mass spectrometry (GC–MS) analysis of the volatile oil revealed the presence of 22 compounds. Citronellal (36.88%) and cephrol (12.42%) were major compounds. The screening for pesticide-likeness complied with Tice criteria. Further prediction of activity spectra for substances (PASS) identified seventeen compounds with significant acetylcholinesterase (AChE) inhibitory potential (Pa > 0.5). Environmental assessment indicated low mammalian toxicity and mostly high biodegradability. Humulene was determined to possess the lowest energy gap value, 6.271 eV, from Density Functional Theory (DFT). Its softness value (0.318 eV⁻¹) showed charge transfer tendecy. The molecular docking results showed high docking score values of humulene and menthoglycol across various targets. Humulene demonstrated the highest binding affinity for AChE (−8.3 kcal/mol; Ki = 0.8 μM) and ecdysone receptor (−8.8 kcal/mol; Ki = 0.3 μM) while menthoglycol had the highest binding affinity toward juvenile hormone-binding protein (−7.7 kcal/mol; Ki = 2.3 μM). These values were more negative than the reference compound dichlorvos (-5.3 to -5.6 kcal/mol). The 3D structures were found to be stable based on simulation studies. Experimental studies are required to confirm the potential of A. auriculiformis essential oil as an eco-friendly alternative to synthetic pesticides.