Ionic liquid-aqueous solution ultrasonic-assisted extraction of camptothecin and 10-hydroxycamptothecin from Camptotheca acuminata samara

In this paper, ionic liquid-aqueous solution ultrasonic-assisted extraction (ILUAE) has been successfully applied in extracting camptothecin and 10-hydroxycamptothecin from Camptotheca acuminata samara. The ionic liquids with different cations and anions have been investigated, and 0.75 M 1-octyl-3-methylimidazolium bromide was selected as solvent. In addition, the ultrasonic parameters including ultrasonic power, time for ultrasonic treatment and solid–liquid ratio have been optimized by Response Surface Methodology. Compared with conventional solvent extraction, ILUAE exhibited higher efficiency (camptothecin increased by 13.96% and 10-hydroxycamptothecin increased by 24.04%, respectively) and shorter extraction time (decreased from 6 h to 1.75 h for extracting three times), which indicated that ILUAE was an efficient, rapid and simple sample preparation technique.