COSMO-RS guided screening of deep eutectic solvent extraction for essential oil from Ligusticum chuanxiong: optimization, composition analysis, and acetylcholinesterase inhibitory activity.

Essential oil of Ligusticum chuanxiong (EO-LC) exhibits notable diverse biological activities, presenting considerable potential for aromatherapy and pharmaceutical applications. Deep eutectic solvents (DESs) are an effective extraction solvent for essential oils. According to thermodynamic analysis from the COSMO-RS model and subsequent experimental validation, betaine/lactic acid (2 : 1) was identified as the optimum candidate and the optimal extraction conditions were established as follows: a water content of 48%, a liquid-to-material ratio of 8.5 : 1 mL g-1, and an extraction time of 2.9 h. Compared to traditional steam distillation (0.44%), DES-based extraction significantly increased the EO-LC yield to 1.14 ± 0.07%, while simultaneously improving the chemical diversity and the relative contents of its major active constituents. Furthermore, EO-LC displayed excellent acetylcholinesterase inhibitory activity (IC50 value of 41.25 µg mL-1) through hydrogen bonding and hydrophobic interactions and van der Waals forces were identified as the primary driving forces for this efficient extraction of EO-LC. This work provides robust theoretical support for the rational design of DESs in EO-LC extraction, and offers novel insights into the efficient utilization of EO-LC.