Antioxidant contents and properties as quality indices of rye cultivars

Contents and properties of antioxidants in the whole grain, a fraction of pericarb with testa and endosperm with embryo of rye (Secale cereale L.) cv. Amilo, cv. Warko and cv. Dańkowskie Złote, grown in 2004, in Poland, were studied as quality indices of rye cultivars. The characteristics of rye cultivars were based on the trolox equivalent antioxidant capacity (TEAC) of the phosphate-buffered saline (PBS) and 80% methanolic extracts determined by the ABTS+ radical-scavenging method, and on superoxide dismutase-like activity (SOD) of PBS extracts. The results obtained were supported by the determination of the total phenolic compounds (TPC), total flavonoids (TF), tocopherols (T) and tocotrienols (T3), inositol phosphates (IP), reduced (GSH) and oxidized glutathione (GSSG) contents, and glutathione peroxidase activity (GPx) of the respective extracts originating from the whole grain and its morphological fractions. The reduced/oxidized glutathione status of three rye cultivars was examined as a potential index of balance between oxidative stress and antioxidant system. The results of this study suggest that the content and properties of antioxidants in pericarb with testa fraction rather than in the whole grain may serve as quality indices of rye cultivars. The determination of correlation coefficients between antioxidant properties and antioxidant content should be carried out in this respect.