Analysis of theaflavins and thearubigins from black tea extract by MALDI-TOF mass spectrometry

J Agric Food Chem. 2004 May 5;52(9):2455-61. doi: 10.1021/jf035427e.


Black tea contains two major groups of pigments, theaflavins (TFs) and thearubigins (TRs). TFs contain a bis-flavan substituted 1,2-dihydroxy-3,4-benzotropolone moiety. Unlike the TFs, TRs have not yet been characterized. The chemical structure of the TRs remains a mystery. The present paper reports our effort to study the structure of TFs and TRs using delayed pulsed ion extraction of ions generated via the matrix-assisted laser desorption ionization (MALDI) technique, on line with a Linear time-of-flight (TOF) mass spectrometer. Spectra of standard TFs show not only pseudomolecular ions but also ions resulting from fragmentation. The analysis of MALDI-TOF spectra of black tea fractions shows the structure of some TRs, which are similar to those of TFs because the same loss of mass is observed.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Biflavonoids / analysis*
  • Biflavonoids / chemistry
  • Camellia sinensis / chemistry*
  • Catechin / analogs & derivatives*
  • Catechin / analysis*
  • Catechin / chemistry
  • Fermentation
  • Molecular Structure
  • Phenols / analysis*
  • Phenols / chemistry
  • Plant Extracts / chemistry*
  • Plant Leaves / chemistry*
  • Polyphenols
  • Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization*


  • Biflavonoids
  • Phenols
  • Plant Extracts
  • Polyphenols
  • thearubigin
  • theaflavin
  • Catechin