title: Ionic liquids based simultaneous ultrasonic and microwave assisted extraction of phenolic compounds from burdock leaves.
abstract: The ionic liquids based simultaneous ultrasonic and microwave assisted extraction (IL-UMAE) technique was first proposed and applied to isolate compounds. The ionic liquids comprising a range of four anions, five 1-alkyl-3-methylimidazolium derivatives were designed and prepared. The results suggested that varying the anion and cation both had apparent effects on the extraction of phenolics. The results also showed that irradiation power, time and solid-liquid ratio significantly affected the yields. The yields of caffeic acid and quercetin obtained by IL-UMAE were higher than those by regular UMAE. Compared with conventional heat-reflux extraction (HRE), the proposed approach exhibited higher efficiency (8-17% enhanced) and shorter extraction time (from 5h to 30s). The results indicated ILUMAE to be a fast and efficient extraction technique. Moreover, the proposed method was validated by the reproducibility and recovery experiments. The ILUMAE method provided good recoveries (from 96.1% to 105.3%) with RSD lower than 5.2%, which indicated that the proposed method was credible. Based on the designable nature of ionic liquids, and the rapid and highly efficient performance of the proposed approach, ILUMAE provided a new alternative for preparation of various useful substances from solid samples.
authors.affiliation: State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, PR China. louzaixiang@126.com
authors.forename: Zaixiang
authors.initials: Z
authors.lastname: Lou
authors.forename: Hongxin
authors.initials: H
authors.lastname: Wang
authors.forename: Song
authors.initials: S
authors.lastname: Zhu
authors.forename: Shangwei
authors.initials: S
authors.lastname: Chen
authors.forename: Ming
authors.initials: M
authors.lastname: Zhang
authors.forename: Zhouping
authors.initials: Z
authors.lastname: Wang
mesh_terms: D031170:Arctium / Q000737:chemistry*; D002109:Caffeic Acids / Q000737:chemistry / Q000302:isolation & purification; D052578:Ionic Liquids / Q000737:chemistry*; D008872:Microwaves; D010636:Phenols / Q000737:chemistry* / Q000302:isolation & purification; D018515:Plant Leaves / Q000737:chemistry; D011794:Quercetin / Q000737:chemistry / Q000302:isolation & purification; D013010:Sonication; D013997:Time Factors
chemical_list: D002109:Caffeic Acids; D052578:Ionic Liquids; D010636:Phenols; D011794:Quercetin; C040048:caffeic acid