Genetic variation of carotenoids, vitamin E and phenolic compounds in Provitamin A biofortified maize

BACKGROUND: Biofortified maize is not only a good vehicle for provitamin A carotenoids for vitamin A deficient populations in developing countries but also a source of vitamin E, tocochromanols and phenolic compounds, which have antioxidant properties. Using high-performance liquid chromatography and a total antioxidant performance assay, the present study analyzed the antioxidant variation and antioxidant activity of 36 provitamin A improved maize hybrids and one common yellow maize hybrid. RESULTS: The ranges of major carotenoids in provitamin A carotenoids biofortified maize were zeaxanthin [1.2-13.2 mu g g(-1) dry weight (DW)], beta-cryptoxanthin (1.3-8.8 mu g g(-1) DW) and beta-carotene (1.3-8.0 mu g g(-1) DW). The ranges of vitamin E compounds identified in provitamin A carotenoids biofortified maize were alpha-tocopherol (3.4-34.3 mu g g(-1) DW), gamma-tocopherol (5.9-54.4 mu g g(-1) DW), alpha-tocotrienol (2.6-19.5 mu g g(-1) DW) and gamma-tocotrienol (45.4 mu g g(-1) DW). The ranges of phenolic compounds were gamma-oryzanol (0.0-0.8 mg g(-1) DW), ferulic acid (0.4-3.6 mg g(-1) DW) and p-coumaric acid (0.1-0.45 mg g(-1) DW). There was significant correlation between alpha-tocopherol and cis isomers of beta-carotene (P < 0.01). Tocotrienols were correlated with alpha-tocopherol and gamma-oryzanol (P < 0.01). CONCLUSION: Genotype was significant in determining the variation in beta-cryptoxanthin, beta arotene, alpha-tocopherol and gamma-tocopherol contents (P < 0.01). A genotype x environment interaction was observed for gamma-tocopherol content (P < 0.01). (c) 2016 Society of Chemical Industry. (C) 2016 Society of Chemical Industry.