Estimation of total phenolic content and other oxidation substrates in plant tissues using Folin-Ciocalteu reagent.
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.
Ainsworth
Elizabeth A
EA
USDA ARS Photosynthesis Research Unit, Urbana, Illinois 61801, USA. ainswort@uiuc.edu
Gillespie
Kelly M
KM
D003124:Colorimetry / Q000379:methods*; D007202:Indicators and Reagents; D008982:Molybdenum; D010084:Oxidation-Reduction; D010636:Phenols / Q000032:analysis* / Q000378:metabolism; D010944:Plants / Q000737:chemistry / Q000378:metabolism*; D013057:Spectrum Analysis / Q000379:methods; D017973:Tungsten Compounds
C029556:Folin's phenol reagent; D007202:Indicators and Reagents; D010636:Phenols; D017973:Tungsten Compounds; D008982:Molybdenum