Optimization of the process of extracting essential oil of rosemary by hydro distillation with different auxiliary methods

This study investigated the anti-inflammatory active components of rosemary essential oil (RME) through in vitro assays on RAW264.7 cells and optimized the extraction process using the content of these components and the extraction yield as evaluation criteria. RME was subjected to molecular distillation, and the composition of each fraction was analyzed by GC-MS. The cytotoxicity of the fractions was evaluated in an LPS-induced inflammation model using the MTT assay. Anti-inflammatory activities were assessed by measuring TNF-α and IL-1β levels, and the primary anti-inflammatory components were identified via OPLS analysis. The results indicated that α-pinene, 1,8-cineole, and D-camphor were the primary contributors to RME's anti-inflammatory effects. A comparison of ultrasound microwave, and enzyme-assisted hydro distillation methods revealed enzyme-assisted hydro distillation, as the optimal technique. The optimal extraction parameters were 0.50% enzyme concentration, 88 min of enzyme incubation, and 53 °C enzyme temperature. This optimized process is stable, reliable, and reproducible, providing a robust foundation for industrial-scale production and further development of RME as a medicinal resource. • Exploring the main anti-inflammatory components of rosemary essential oil using molecular distillation technology. • Maximizing the extraction efficiency of rosemary essential oil through EHD extraction. • Establishing an extraction kinetics model to compare the kinetic differences in extraction rates. • Multi-index comprehensive evaluation of rosemary essential oil extraction.