Ultrasound-assisted Extraction of Imperatorin and Isoimperatorin from Roots of Angelica Dahurica

Imperatorin and isoimperatorin are important components of Angelica dahurica with many beneficial functions to human health. In this study, an ultrasound-assisted extraction technique has been developed for the fast extraction of imperatorin and isoimperatorin from Angelica dahurica root. The high extraction yield of imperatorin and isoimperatorin was obtained under optimum extraction conditions: ultrasonication time 20 min, extraction temperature 30 degrees C, ultrasound power 240w, ethanol concentration 80%, and ratio of solvent volume to sample weight 12:1 (ml/g), particle size 60 meshes. Compared to heat-reflux extraction, ultrasound-assisted extraction reduced extraction time and obtained higher percentage extracted of imperatorin and isoimperatorin. Scanning electron micrographs revealed that ultrasound could result in the destruction of cell walls, which increased the mass transfer rate of the solvents into the root materials.