Effect of sprouting on the concentration of phenolic acids and antioxidative capacity in wheat cultivars (<em>Triticum aestivum</em> ssp. <em>aestivum</em> L.) in dependency of nitrogen fertilization


  • N. Engert
  • A. John
  • W. Henning
  • B. Honermeier


The study was conducted to analyze the effects of sprouting on content and composition of phenolic acids (PA) and antioxidative capacity by the Folin-Ciocalteu (total phenolic content (TPC)) and ORAC (Oxygen Radical Absorbance Capacity) assay depending on nitrogen application and cultivar. Three wheat cultivars (cv. Tommi, cv. Privileg and cv. Estevan) were treated with two different nitrogen (N) levels (N1 without N and N2 with 150 kg N/ha). Three fractions of the grinded wheat caryopses (free, free-insoluble and bound phenolic acids) were extracted. Mean values for total phenolic acids (TPA) ranged between 498.1 and 1726.2 μg GAE/g with signifi cant differences for the cultivars in not sprouted samples. Nitrogen fertilization showed signifi cant differences with lower TPA contents for not fertilized grain. Even the interaction cultivar x nitrogen was signifi cant for not sprouted grain. The statistical analysis of sprouting time did not show effects on TPA values after 24 h and 48 h of sprouting. In the present study no significant influence of cultivar or nitrogen application was identified for TPC and ORAC values. In contrary to that, the effects of sprouting time on the antioxidative capacity by Folin-Ciocalteu and ORAC were significant. After 48 h of sprouting the values of TPC (2575.6 μg GAE/g) and ORAC (32.6 μmol TE/g) were significantly higher than for not sprouted wheat samples (TPC: 2054.8 μg GAE/g, ORAC: 28.2 μmol TE/g). The longer the sprouting time was, the higher the antioxidative capacity of free phenolic acids, indicating that more free phenolic acids were released and other phytochemicals might have been present after sprouting. Since there are only little information about the effect of sprouting time on phenolic acids and antioxidative capacity in dependence on nitrogen application further studies need to be conducted.