Abstract: Epidemiological data suggest that consumption of whole-grain and bran may help to prevent cardiovascular diseases, diabetes and certain forms of cancer. The beneficial health effects are usually attributed to the presence of dietary fibre and bioactive secondary metabolites, including phenolic acids. Wheat is an important component of the human diet and may be a significant source of phenolic antioxidants. To date, few studies have investigated the effect of various agricultural practices on levels of secondary metabolites in crops. The aim of this work was to determine the phenolic acid content in four winter wheat cultivars, grown using conventional and organic agricultural practices. Five phenolic acids were detected by HPLC analyses. Ferulic acid was the predominant phenolic acid in the grain of all tested wheat varieties. The remaining phenolic acids, i.e. sinapic acid, p-coumaric acid, vanillic acid, and p-hydroxybenzoic acid, were present in considerably lower amounts. Significant differences among cultivars in concentration of particular phenolic acids, as well as in the total phenolic acid content were observed. The effect of various agricultural practices on phenolic acid levels in wheat grains was also analysed. Organically grown plants are usually considered to contain more secondary metabolites. In this study, however, organic agriculture did not lead to a significant increase in phenolic acids. Only a small, statistically irrelevant trend towards higher levels of phenolic acids in organic wheat samples was demonstrated.
Reference: Zuchowski, J. et. al. (2009). Phenolic acid content of organic and conventionally grown winter wheat. Cereal Research Communications 37(2): 189-197. Available online at: http://dx.doi.org/10.1556/CRC.37.2009.2.5