Research survey on iridoid and phenylethanoid glycosides among seven populations of Euphrasia rostkoviana Hayne from the Alps

Phytochemistry. 2017 May;137:72-80. doi: 10.1016/j.phytochem.2017.02.013. Epub 2017 Feb 21.

Abstract

The traditional use of extracts of Euphrasia rostkoviana to relieve ocular inflammation or infections is well documented and supported by clinical studies. Various classes of chemical compounds such as iridoids, phenylethanoids, flavonoids and hydroxycinnamic acids have been reported. The present work aims to assess the chemical diversity among seven populations of Euphrasia rostkoviana found in northern Italy. A meticulous separation of components led to the isolation and structural characterization of two previously unrecorded phenylethanoids methoxycrassifolioside and deoxycrassifolioside and one previously undescribed terpene glucoside (1E,6E)-8-hydroxy-3,7-dimethyl-octa-1,6-dienyl 1-O-β-D-glucopyranoside. We have also identified known phenylethanoids and iridoids that are reported in this genus for the first time. Finally, a targeted quantitative analysis for the standardization of herbal preparations revealed that iridoids occur in all populations whereas the presence and the levels of rutin and phenylethanoids are highly variable.

Keywords: Aucubin (PubChem CID: 91458); Catalpol (PubChem CID: 91520); Citronellenyl glucoside; Crassifolioside; Crassifolioside (PubChem CID: 102193658); Ehrenoside; Ehrenoside (PubChem CID: 10259536); Euphrasia rostkoviana; Geniposidic acid (PubChem CID: 443354); Iridoids; Mussaenosidic acid (PubChem CID: 21633105); Orobanchaceae; Phenylethanoid glycosides; Rutin (PubChem CID: 5280805); Salidroside (PubChem CID: 159278); Verbascoside; Verbascoside (PubChem CID: 5281800).

MeSH terms

  • Euphrasia / chemistry*
  • Flavonoids / chemistry
  • Flavonoids / isolation & purification
  • Glucosides / chemistry
  • Glucosides / isolation & purification
  • Glycosides / chemistry*
  • Glycosides / isolation & purification
  • Iridoids / chemistry*
  • Iridoids / isolation & purification
  • Italy
  • Molecular Structure
  • Phytochemicals / chemistry
  • Phytochemicals / isolation & purification
  • Plant Components, Aerial / chemistry
  • Plant Extracts / chemistry
  • Plants, Medicinal / chemistry

Substances

  • Flavonoids
  • Glucosides
  • Glycosides
  • Iridoids
  • Phytochemicals
  • Plant Extracts