Rapid Analysis of Phenolic Acid, Flavonoids and Sterols in Commercial Extracts of Taraxacum officinale Web. ex Wigg. Leaves and Roots using UPLC-UV-ELSD/MS

B Avula; YH Wang; CS Rumalla; TJ Smillie; DE Webster; CH Kim; E Bejar; IA Khan

doi:10.1055/s-0031-1273602

Planta Medica, Table of Contents

Rapid Analysis of Phenolic Acid, Flavonoids and Sterols in Commercial Extracts of Taraxacum officinale Web. ex Wigg. Leaves and Roots using UPLC-UV-ELSD/MS

B Avula ¹, YH Wang ¹, CS Rumalla ¹, TJ Smillie ¹, DE Webster ³, CH Kim ³, E Bejar ³, IA Khan ¹^,²^,⁴

¹National Center for Natural Products Research, School of Pharmacy, The University of Mississippi, MS 38677, USA
²Department of Pharmacognosy, School of Pharmacy, The University of Mississippi, University, MS 38677, USA
³Global Science, Product Safety and Compliance, Herbalife International of America, Torrance, CA 90502, USA
⁴Department of Pharmacognosy, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia

Abstract

Dandelion (Taraxacum officinale Web. Ex Wigg) is widely used in Asia, Europe, and North America as a botanical supplement to help support digestive and liver health as well as the elimination of excess water. The roots are primarily used for gastrointestinal health and biliary function, while the leaves are used to support kidney and diuretic functions [1]. A new rapid Ultraperformance Liquid Chromatography (UPLC-UV-ELSD/MS) method was developed for simultaneous analysis of four phenolic acids (chlorogenic acid, caffeic acid, chicoric acid, 3, 5 dicaffeoylquinic acid), one flavonoid glycoside (luteolin-7-O-glucoside) and one triterpene (taraxasterol) in commercial extracts of dandelion leaves and roots. The chromatographic separation using UPLC was achieved by a reversed phase (RP-18) column and a water/acetonitrile gradient containing 0.05% formic acid as the mobile phase. Compounds were detected with photo diode array (PDA) combined with evaporative light scattering detector (ELSD) and MS detection. LC-MS coupled with electrospray ionization (ESI) was used for the identification of six compounds in commercial dandelion samples. This method involved the use of the [M+Na]⁺, [M+H]⁺ and [M-H]^- ions for five compounds in the positive and negative ion mode with selected ion monitoring (SIR). Hydroxycinnamic acid derivatives, in particular caffeic acid esters such as chlorogenic, dicaffeoyltartaric (chicoric) acid and monocaffeoyltartaric acids are more abundant phenolic compounds in leaves compared to roots. The compound correlating with the largest peak in both roots and leaves is chicoric acid. Therefore, the combined use of UPLC with both PDA and ELSD allows for simultaneous fast analysis of phenolic acids, flavonoids and triterpenes from dandelion, which can be used for quality control of T. officinale to distinguish roots from leaves, as well as to identify possible adulterants.

Fig.1 UPLC-PDA-ELSD chromatograms of standard mix (A), leaves (B) and root (C) samples of T. officinale using PDA at 350nm and ELS detectors (1) chlorogenic acid, (2) caffeic acid, (3) luteolin-7-O-glucoside, (4) 3,5 dicaffeoylquinic acid, (5) chicoric acid, (6) taraxasterol

Acknowledgements: This research is supported in part by Global Science, Product Safety and Compliance, Herbalife International of America, Torrance, CA 90502, USA, and the United States Department of Agriculture, Agricultural Research Service, Specific Cooperative Agreement No. 58–6408–2-0009 and the authors would like to thank Annette Ford for the extractions of plant samples.

References: [1] Abascal K, Yarnell E, (2009) Integrative Med, 8(2): 35–38.