Phytochemical and Nutraceutical Profiles of Blue Maize (Zea Mays) Hybrids Evaluated in Two Locations-Edición Única

Abstract

Recent years have seen an increased interest in blue maize (Zea mays) due to its proven nutraceutical properties. In recent times blue maize hybrids have been developed through a landrace starting point and by genetic improvement. These hybrids are being evaluated for their environmental stability and agronomic profile. With this objective, 25 promising hybrid blue maize crosses were selected from the improvement program at INIFAP-Bajío and planted in 2 contrasting environments located in the Bajío area and Morelia. The objective of this work was to evaluate the phytochemical and nutraceutical profiles of these hybrids and to select those with the best features. An initial bulk analysis was elaborated to elucidate any significant differences between both locations. Free and bound phenolic acids were evaluated using the Folin-Ciocalteu method as were their antioxidant capacity using the Oxygen Radical Absorbance Capacity (ORAC) method. Bound ferulic acid content was determined by High Pressure Liquid Chromatography (HPLC) and total monomeric anthocyanin content was determined by the pH differential method. Soluble carbohydrates, protein methods and biophysical properties like kernel color and endosperm texture were also determined. The results indicate a significant difference among the 25 genotypes evaluated. With a number of genotypes having free and bound phenolic acids content higher than those previously reported; their respective antioxidant capacities also showed high levels. Bound phenolic acid showed a significant difference between environments whereas anthocyanins were not affected by the environment. Soluble carbohydrate and soluble protein determination confirmed that white maize conversion retains key phytochemical properties. Results show a surprising correlation between chroma and anthocyanin content as well as for other kernel color measurements. Overall, the 25 hybrid blue maize genotypes evaluated were little influenced by the environment and retained high levels of health promoting phytochemicals and nutraceutical activity. A number of genotypes exhibited high phytochemical and nutraceutical profiles that can be used as a basis for crop improvement in further studies involving breeding blue maize. Especially genotype 22 which showed stability among regions and across most phytochemical traits, having high anthocyanin content, ferulic acid and antioxidant capacity.