title: Determination of the esculetin contents of medicinal plants by liquid chromatography-tandem mass spectrometry.
abstract: We developed a LC-MS/MS method for the determination of esculetin contents in medicinal plants. The analysis was performed using multiple reaction monitoring in negative mode, and an XBridge™ C(18) column (2.1 × 100 mm, 3.5 µm) was used. Methanol and 0.1% formic acid were used for gradient analysis. The calibration curve showed good linearity (r(2)  > 0.9993). The limits of detection and quantitation were 0.02 and 0.07 ng/mL, respectively. The intra-day and inter-day precisions were 1.5-6.8 and 2.0-5.3%, respectively, and the accuracy was 102.0-110.2%. The contents of esculetin in 35 different plants were determined, and Fraxini Cortex showed the highest content of esculetin (761-5475 mg/kg). In Mori Folium and Artemisiae Capillaris Herba, 5.2-21.5 and 7.0-17.6 mg/kg of esculetin were found, respectively. In other medicinal plants, no esculetin was detected, or it was present at a concentration less than 10 mg/kg. The analysis method appears to be simple, sensitive and reproducible. Contrary to expectations based on traditional medical knowledge, although Artemisiae Capillaris Herba contains a large amount of esculetin, it appears from this study that Fraxini Cortex contains a greater amount. The pharmacological effects of esculetin isolated from medicinal plants should be investigated as part of new medicines development.
authors.affiliation: Department of Veterinary Pharmacology and Toxicology, College of Veterinary Medicine, Konkuk University, 1 Hwayang-dong, Gwangjin-gu, Seoul, Republic of Korea.
authors.forename: Eun-Sun
authors.initials: ES
authors.lastname: Yun
authors.forename: Sung-Kyu
authors.initials: SK
authors.lastname: Park
authors.forename: Bog-Soon
authors.initials: BS
authors.lastname: Kim
authors.forename: Young-Zoo
authors.initials: YZ
authors.lastname: Chae
authors.forename: Soo-Min
authors.initials: SM
authors.lastname: Cho
authors.forename: Hee
authors.initials: H
authors.lastname: Yi
authors.forename: Hee-Jung
authors.initials: HJ
authors.lastname: Cho
authors.forename: Ho-Chul
authors.initials: HC
authors.lastname: Shin
mesh_terms: D019306:Artemisia / Q000737:chemistry; D002853:Chromatography, Liquid / Q000379:methods*; D031661:Fraxinus / Q000737:chemistry; D016014:Linear Models; D010936:Plant Extracts / Q000737:chemistry*; D010946:Plants, Medicinal / Q000737:chemistry*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D053719:Tandem Mass Spectrometry / Q000379:methods*; D014468:Umbelliferones / Q000032:analysis* / Q000737:chemistry
chemical_list: D010936:Plant Extracts; D014468:Umbelliferones; C007628:esculetin