TOTAL ANTHOCYANINS AND COLOR PARAMETERS IN PURPLE CORN INBRED LINES

Abstract

Purple corn (Zea mays L.) contains natural pigments of the anthocyanin type. These pigments have bioactive properties that may be used in the nutraceutical, food and textile industries. Before affirming that maize is an important source of this flavonoid, it is necessary to assess its productive potential and to direct plant breeding efforts towards increasing total concentration in grains and other storage structures. In the pigmented maize breeding program at Colegio de Postgraduados, during the Spring-Summer 2015 crop season, 124 S₂ inbred lines were selected and most were classified on a color scale as intense purple and reddish-purple. Total anthocyanin content (TAC) in the whole grain, pericarp and aleurone, as well as color in the HunterLab scale were also determined to assess their anthocyanins productive potential, to characterize them by their color parameters, to identify the grain structure with the highest TAC, and to select elite inbred lines that might be used in the breeding program. On average, the inbred lines had 0.085, 0.959 and 0.031 g of TAC 100 g^-1 in the whole grain, pericarp and aleurone, respectively; TAC was higher in pericarp than in the whole grain and aleurone. Mean color values in grain were 10.5, 3.3, 2.2 and 39.9º for L, a, b and hue angle, respectively. These values indicate red to dark yellow colors, which were not related to the color scale (blue, red, purple and their variants) nonetheless, they are quantitative parameters of color. According to their chroma value (4.1), grain color was of low saturation (dull color). In general, the lines showed high productive potential of anthocyanins; nevertheless, only 25 % of them were considered as elite lines, and the ten lines with the highest productive potential were: 118, 122, 198, 121, 120, 117, 147, 161, 123 and 124.