title: Ultrasonic extraction and separation of anthraquinones from Rheum palmatum L.
abstract: The ultrasonic nebulization extraction (UNE) was developed and applied to extract anthraquinones (emodin, aloe-emodin and rhein) from Rheum palmatum L. Several parameters of UNE, including type of extraction solvent, concentration of extraction solvent, volume of extraction solvent, extraction time and ultrasonic power, were studied and the optimized parameters were selected. The operation conditions of micellar electrokinetic capillary chromatography (MEKC) were also studied. Under the selected conditions, contents of emodin, aloe-emodin and rhein obtained from different cultivated areas of R. palmatum L. were 1.08-2.04 mg/g, 0.65-1.16 mg/g and 0.70-2.90 mg/g, respectively. The relative standard deviations (RSDs) for emodin, aloe-emodin and rhein were 1.3-2.4%, 1.9-4.7% and 1.3-3.9%, respectively. Compared with maceration extraction (ME), reflux extraction (RE), stirring extraction (SE) and ultrasonic extraction (UE), the proposed method was more efficient, faster and easier to be operated and lower equipment costs and lower extraction temperature were required. The results indicated that UNE was a good alternative method for extracting anthraquinones from R. palmatum L. Compared with traditional extractions, the proposed extraction has a potential in on-line sampling, especially when the gas is used as the carrier of sample.
authors.affiliation: College of Chemistry, Jilin University, Changchun 130012, PR China.
authors.forename: Lu
authors.initials: L
authors.lastname: Wang
authors.forename: Dan
authors.initials: D
authors.lastname: Li
authors.forename: Changli
authors.initials: C
authors.lastname: Bao
authors.forename: Jingyan
authors.initials: J
authors.lastname: You
authors.forename: Ziming
authors.initials: Z
authors.lastname: Wang
authors.forename: Yuhua
authors.initials: Y
authors.lastname: Shi
authors.forename: Hanqi
authors.initials: H
authors.lastname: Zhang
mesh_terms: D000880:Anthraquinones / Q000302:isolation & purification*; D020374:Chromatography, Micellar Electrokinetic Capillary; D004591:Electrophoresis, Polyacrylamide Gel; D012250:Rheum / Q000737:chemistry*; D012997:Solvents; D014465:Ultrasonics
chemical_list: D000880:Anthraquinones; D012997:Solvents