Meeting Abstract - Poster Presentation

Phenol profile and antioxidant activity levels of black sorghums grown in different environmental conditions
L. DYKES (1), W. L. Rooney (2), G. C. Peterson (3), L. W. Rooney (1)
(1) Texas A&M University, Dept. Soil & Crop Sciences, Cereal Quality Lab, College Station, TX, USA; (2) Texas A&M University, Dept. Soil & Crop Sciences, College Station, TX, USA; (3) Texas Agricultural Experiment Station, Lubbock, TX, USA
Cereal Foods World 52:A40

Pigmented sorghums, especially those with a black pericarp, have high levels of 3-deoxyanthocyanins. However, information on phenol profile and antioxidant activity levels of black sorghum genotypes grown in different environmental conditions is lacking. A wide variety of black sorghum lines and hybrids with or without a pigmented testa were grown in different environments and were analyzed for total phenols, condensed tannins, and antioxidant activity using the Folin-Ciocalteu, vanillin/HCl, ABTS, and DPPH assays. Phenolic profiles of the black sorghums were determined using HPLC-PDA. Total phenols, condensed tannins, and antioxidant activity levels varied among the genotypes. The 3-deoxyanthocyanins were the main flavonoids detected in black sorghums with the hybrids having the lowest levels. Small amounts of flavones, such as apigenin and luteolin, were also detected. The main phenolic acids detected were small amounts of caffeic and ferulic acids. The phenol levels and profiles of black sorghums differed significantly when the grain was grown in various environments. This study shows that the major flavonoids in black sorghums are the 3-deoxyanthocyanins and the phenol type and concentration depend on environmental conditions.