Use of Innovative (Micro)Extraction Techniques to Characterise Harpagophytum procumbens Root and its Commercial Food Supplements

Phytochem Anal. 2018 May;29(3):233-241. doi: 10.1002/pca.2737. Epub 2017 Nov 16.


Introduction: For the determination of harpagoside and the wide phenolic pattern in Harpagophytum procumbens root and its commercial food supplements, dispersive liquid-liquid microextraction (DLLME), ultrasound-assisted DLLME (UA-DLLME), and sugaring-out liquid-liquid extraction (SULLE) were tested and compared.

Objectives: In order to optimise the extraction efficiency, DLLME and UA-DLLME were performed in different solvents (water and aqueous solutions of glucose, β-cyclodextrin, (2-hydroxypropyl)-β-cyclodextrin, sodium chloride, natural deep eutectic solvent, and ionic liquid).

Material and methods: The plant material was ground and sieved to obtain a uniform granulometry before extraction. Commercial food supplements, containing H. procumbens are commercially available in Italy.

Results: The most effective sodium chloride-aided-DLLME was then optimised and applied for analyses followed by HPLC-PDA. For comparison, microwave-assisted extraction was performed using the same solvents and the best results were obtained using 1% of β-cyclodextrin or 15% of sodium chloride.

Conclusion: All commercial samples respected the European Pharmacopoeia monograph for this plant material, showing a harpagoside content ≥ 1.2%. Copyright © 2017 John Wiley & Sons, Ltd.

Keywords: DLLME; Harpagophytum procumbens; IL; MAE; NADES.

Publication types

  • Comparative Study

MeSH terms

  • 2-Hydroxypropyl-beta-cyclodextrin / chemistry
  • Chromatography, High Pressure Liquid / methods
  • Dietary Supplements / analysis*
  • Glucose / chemistry
  • Glycosides / analysis*
  • Harpagophytum / chemistry*
  • Italy
  • Limit of Detection
  • Liquid Phase Microextraction / methods*
  • Microwaves
  • Phenols / analysis*
  • Plant Roots / chemistry*
  • Pyrans / analysis*
  • Sodium Chloride / chemistry
  • Solvents / chemistry
  • Water / chemistry


  • Glycosides
  • Phenols
  • Pyrans
  • Solvents
  • Water
  • 2-Hydroxypropyl-beta-cyclodextrin
  • Sodium Chloride
  • harpagoside
  • Glucose