Molecules (Mar 2019)

Liquid Phase and Microwave-Assisted Extractions for Multicomponent Phenolic Pattern Determination of Five Romanian <i>Galium</i> Species Coupled with Bioassays

  • Andrei Mocan,
  • Alina Diuzheva,
  • Sabin Bădărău,
  • Cadmiel Moldovan,
  • Vasil Andruch,
  • Simone Carradori,
  • Cristina Campestre,
  • Angela Tartaglia,
  • Marta De Simone,
  • Dan Vodnar,
  • Matteo Tiecco,
  • Raimondo Germani,
  • Gianina Crișan,
  • Marcello Locatelli

DOI
https://doi.org/10.3390/molecules24071226
Journal volume & issue
Vol. 24, no. 7
p. 1226

Abstract

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Background: Galium is a plant rich in iridoid glycosides, flavonoids, anthraquinones, and small amounts of essential oils and vitamin C. Recent works showed the antibacterial, antifungal, antiparasitic, and antioxidant activity of this plant genus. Methods: For the determination of the multicomponent phenolic pattern, liquid phase microextraction procedures were applied, combined with HPLC-PDA instrument configuration in five Galium species aerial parts (G. verum, G. album, G. rivale, G. pseudoaristatum, and G. purpureum). Dispersive Liquid–Liquid MicroExtraction (DLLME) with NaCl and NAtural Deep Eutectic Solvent (NADES) medium and Ultrasound-Assisted (UA)-DLLME with β-cyclodextrin medium were optimized. Results: The optimal DLLME conditions were found to be: 10 mg of the sample, 10% NaCl, 15% NADES or 1% β-cyclodextrin as extraction solvent—400 μL of ethyl acetate as dispersive solvent—300 μL of ethanol, vortex time—30 s, extraction time—1 min, centrifugation at 12000× g for 5 min. Conclusions: These results were compared with microwave-assisted extraction procedures. G. purpureum and G. verum extracts showed the highest total phenolic and flavonoid content, respectively. The most potent extract in terms of antioxidant capacity was obtained from G. purpureum, whereas the extract obtained from G. album exhibited the strongest inhibitory effect against tyrosinase.

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