Polyphenol composition and antioxidant capacity of Epilobium species

Barbara Hevesi Tóth, Balázs Blazics, Ágnes Kéry

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44 Citations (Scopus)


Epilobium species (Onagraceae) are commonly used herbal remedies in traditional, adjuvant therapy of benignus prostate hyperplasia (BPH), however the pharmacological and clinical standardization of commercially available Epilobii herba (willow-herb) remains difficult. Willow-herb products usually consist of mixtures from various species, with different phenoloid content, often only partially identified. The present study reports comprehensive LC-MS/MS investigation on the polyphenol composition of the most common Epilobium species, emphasizing the pharmaceutical importance of a uniform standardization protocol in case of their products. The antioxidant capacity of species was evaluated by a simple spectrophotometric method, using ABTS{radical dot}+ (2,2′azinobis-(3-ethylbenzthiazoline-6-sulfonic acid)). High ratio of macrocyclic tannins, mainly oenothein B was identified in all Epilobium species examined. Flavonoid composition of Epilobium extracts showed several differences, especially comparing E. angustifolium to other species. Myricetin, quercetin, kaempferol and their various glycosides were dominant in samples, but their combination and ratio were distinctive in all cases. Epilobium extracts showed high radical-scavenger activity, comparable to that of well-known antioxidants, Trolox and ascorbic acid. Among species examined, extract of Epilobium parviflorum possessed the highest antioxidant capacity (EC50 = 1.71 ± 0.05 μg/ml).

Original languageEnglish
Pages (from-to)26-31
Number of pages6
JournalJournal of Pharmaceutical and Biomedical Analysis
Issue number1
Publication statusPublished - Jan 15 2009



  • BPH
  • Epilobium
  • Oenothein B
  • Polyphenol LC-MS/MS
  • Standardization of phytomedicines

ASJC Scopus subject areas

  • Analytical Chemistry
  • Pharmaceutical Science
  • Drug Discovery
  • Spectroscopy
  • Clinical Biochemistry

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