Protocol abstract

Nature Protocols 2, 875 - 877 (2007)
Published online: 12 April 2007 | doi:10.1038/nprot.2007.102

Subject Categories: Isolation, purification and separation | Model organisms | Plant biology | Biochemistry and protein analysis

Estimation of total phenolic content and other oxidation substrates in plant tissues using Folin–Ciocalteu reagent

Elizabeth A Ainsworth1,2 & Kelly M Gillespie2

Non-structural phenolic compounds perform a variety of functions in plants, including acting as antioxidants. We describe a microplate-adapted colorimetric total phenolics assay that utilizes Folin–Ciocalteu (F–C) reagent. The F–C assay relies on the transfer of electrons in alkaline medium from phenolic compounds to phosphomolybdic/phosphotungstic acid complexes, which are determined spectroscopically at 765 nm. Although the electron transfer reaction is not specific for phenolic compounds, the extraction procedure eliminates approximately 85% of ascorbic acid and other potentially interfering compounds. This assay is performed in microcentrifuge tubes and assessed in a 96-well plate reader. At least 64 samples can be processed in 1 d.

  1. USDA ARS Photosynthesis Research Unit, Urbana, Illinois 61801, USA.
  2. Program in Physiological and Molecular Plant Biology and Institute for Genomic Biology, University of Illinois Urbana-Champaign, 147 ERML, 1201 W. Gregory Drive, Urbana, Illinois 61801, USA.

Correspondence to: Elizabeth A Ainsworth1,2 e-mail: