Capillary zone electrophoresis method for determination of bitter (alpha- and beta-) acids in hop (Humulus lupulus L.) cone extracts

Adv Med Sci. 2009;54(1):41-6. doi: 10.2478/v10039-009-0020-9.

Abstract

Purpose: Humulus lupulus (H. lupulus), more commonly known as hop, is a member of the Cannabaceae family with male and female flowers on separate plants. It is native in Europe including Lithuania, Asia and North America. Hop has been recognized as a medicinal plant for centuries, nevertheless different medicinal activities of hop are currently investigated and discovered. An important class of hop compounds is the hop acids, which are classified as alpha-acids and beta-acids. Different varieties of hops vary in amount and composition of hop acids.

Methods: Simple capillary zone electrophoresis method has been optimized and applied for the analysis of hop acids in hop cone extracts.

Results: With this method the analysis takes ca. 10 min. Repeatability for migration times and peak areas expressed as relative standard deviation were up to 0.21% and 5.96%, respectively.

Conclusions: Comparative results of capillary zone electrophoretic analysis of extracts of different hop varieties and conductometric titration, as a standard method for determination of alpha-acids, are presented. Both methods provide consistent results, however capillary zone electrophoresis is capable of separating co- form of humulones from other forms.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cyclohexenes / analysis*
  • Cyclohexenes / isolation & purification
  • Electrophoresis, Capillary / methods*
  • Flowers / chemistry*
  • Humulus / chemistry*
  • Plant Extracts / chemistry*
  • Reproducibility of Results
  • Species Specificity
  • Spectrophotometry, Ultraviolet
  • Terpenes / analysis*
  • Terpenes / isolation & purification

Substances

  • Cyclohexenes
  • Plant Extracts
  • Terpenes
  • lupulon
  • humulon