Friday, 29 July 2016

Green extraction of polyphenols from whole pomegranate fruit using cyclodextrins

Volume 214, 1 January 2017, Pages 61–66

  • a Laboratory of Chemistry – Biochemistry – Physical Chemistry of Foods, Department of Nutrition & Dietetics, Harokopion University, 70 El. Venizelou Str., Kallithea, 17671 Athens, Greece
  • b Department of Food Science and Technology, Faculty of Agriculture, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
  • c Institute of Nanoscience and Nanotechnology, NCSR “Demokritos”, Patriarchou Gregoriou and Neapoleos Str., Aghia Paraskevi, 15310 Athens, Greece


Holistic approach for the extraction of whole pomegranate polyphenols was proposed.
The solvent system of the extraction was aqueous solutions of cyclodextrins.
Complex formation of polyphenols was investigated with Nuclear Magnetic Resonance Spectroscopy.


Pomegranate is a source of bioactive phytochemicals. The objective of this study was the derivation of a sustainable method to exploit the whole fruit, both edible and non-edible parts, as a source of polyphenols. Pomegranate peel contains a 10-fold higher phenolic content than the pulp. The fruit was freeze-dried and the resulting dry matter was extracted with solid-liquid percolation equipment using non-toxic and eco-friendly extraction solvents: either deionized water or aqueous solutions of cyclodextrins. Cyclodextrins (CDs) are known molecular encapsulators and our results prove enhancement of the extraction of pomegranate polyphenols by 20%. In order to examine the formation of inclusion complexes between CD’s and polyphenols of the extract, polyphenols were isolated using solid-phase extraction. NMR studies with the purified extracts and the individual CDs confirmed inclusion complex formation in water. Pomegranate liquid extracts may be used as raw materials for several end-users in the food, cosmetic and pharmaceutical industries.

Chemical compounds studied in this article

  • Beta-cyclodextrin (PubChem CID: 6518168);
  • Hydroxypropyl-beta-cyclodextrin (PubChem CID: 44134771);
  • DPPH, free radical (PubChem CID: 2735032);
  • Trolox (PubChem CID: 40634)


  • Cyclodextrins;
  • Polyphenols;
  • Inclusion complex formation;
  • NMR spectroscopy;
  • Extraction
Corresponding author.