Deep eutectic solvent-assisted magnetic nanoparticle extraction of curdione from Curcuma wenyujin for analytical and bioactivity evaluation.

To improve the extraction efficiency of hydrophobic bioactive compounds and reduce organic solvent consumption, a deep eutectic solvent-assisted magnetic nanoparticle (DES-MNPs) extraction method was developed for the determination of curdione in Curcuma wenyujin. Ethylene glycol/choline chloride (EG/ChCl) was employed as a hydrogen-bond-rich extraction medium, while dispersed magnetic nanoparticles were introduced to enhance mass transfer and enable rapid magnetic separation. Key extraction parameters were optimized using single-factor experiments combined with a Box-Behnken response surface design. Under the optimized conditions, the curdione concentration reached 0.125 mg/mL, representing a slightly higher yield (11.6%) compared with conventional ultrasound-assisted extraction using 70% ethanol. The improved extraction performance was attributed to the favorable solvation capability of the DES and the enhanced dispersion and mass transfer provided by the magnetic nanoparticles. The applicability of the developed method was further demonstrated through the bioactivity evaluation of the obtained extract, including antibacterial, anti-inflammatory, and antioxidant activities. Overall, this study presents an efficient and environmentally benign sample preparation strategy for the extraction and analysis of hydrophobic natural products from complex plant matrices.