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 µg g−1 dry weight (DW)], β-cryptoxanthin (1.3–8.8 µg g−1 DW) and β-carotene (1.3–8.0 µg g−1 DW). The ranges of vitamin E compounds identified in provitamin A carotenoids biofortified maize were α-tocopherol (3.4–34.3 µg g−1 DW), γ-tocopherol (5.9–54.4 µg g−1 DW), α-tocotrienol (2.6–19.5 µg g−1 DW) and γ-tocotrienol (45.4 µg g−1 DW). The ranges of phenolic compounds were γ-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 α-tocopherol and cis isomers of β-carotene (P < 0.01). Tocotrienols were correlated with α-tocopherol and γ-oryzanol (P < 0.01). CONCLUSION: Genotype was significant in determining the variation in β-cryptoxanthin, β-carotene, α-tocopherol and γ-tocopherol contents (P < 0.01). A genotype × environment interaction was observed for γ-tocopherol content (P < 0.01). © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry