Deep Eutectic Solvents Mediated Optimized Extraction of Lavender Essential Oil: Efficient Camphor Reduction and...

This study developed an eco-friendly extraction method for lavender essential oil (LEO) using customized deep eutectic solvents (DES), with choline chloride-lactic acid (DES3) showing optimal performance. Response surface methodology (RSM) identified the optimal extraction parameters as follows: extraction time of 147 min, DES concentration of 42%, and solid-to-liquid ratio of 1:11. Under these conditions, the LEO yield reached 5.11% ± 0.13%, significantly higher than that obtained using pure water. GC-MS analysis indicated that in LEO extracted with DES3, camphor content decreased from 15.2% to 5.69%. In contrast, the levels of linalool and eucalyptol increased markedly. The reduction in ketone content, coupled with substantial enrichment in alcohols and esters, contributed to a notable enhancement in overall LEO quality. Through molecular docking, the interaction mechanisms between DES3 and key LEO components were elucidated. FT-IR spectroscopy was utilized to characterize the formation of hydrogen bonds and the variations of functional groups within DES3. SEM confirmed DES3 disrupted lavender cell walls to fully release aromatic substances and retain volatiles. Pharmacological evaluation verified that optimized LEO exerted potent anti-inflammatory effects by suppressing xylene-triggered ear swelling and inflammatory infiltration in mice. DES-mediated extraction enables targeted component regulation for high-quality LEO, offering a green strategy for sustainable fragrance-pharmaceutical development.