Comparison of Composition and Bioactivity Between DES and Steam Distillation Extraction of Four Traditional Chinese Spice Plants

Objective This study explored the advantages of deep eutectic solvents (DES) in extracting plant volatile components. We focused on evaluating the efficacy of DES in extracting essential oils (EOs) from Cinnamomum cassia (CC), Thymus mongolicus (TM), Illicium verum (IV), and Curcuma longa (CL). This was compared to the traditional steam distillation method. Methods DES was prepared with a 1:3 ratio of 1,3-butanediol to choline chloride. Its extraction efficiency was compared to steam distillation, and EOs were analyzed using GC-MS. The antioxidant properties of the extracts were assessed using the DPPH assay, and antimicrobial activities were tested against Escherichia coli and Staphylococcus aureus . Results DES extraction enhanced the extraction rate and content of specific compounds in IVEOs and increased the abundance of compounds in CCEOs and TMEOs. The TMEOs extracted with DES exhibited the most potent antioxidant capacity, whereas the CCEOs extracted with DES demonstrated the strongest antibacterial activity. The EOs obtained through DES extraction displayed higher quality and biological activity than those obtained through steam distillation. Conclusion DES is effective for extracting EOs from aromatic plants and may result in oils with enhanced biological activities. Further optimization of the DES formulation could enhance extraction efficiency and improve oil quality.