DETERMINATION OF PHENOLICS, FLAVONOIDS AND ANTHOCYANINS IN PIGMENTED AND NON-PIGMENTED MAIZE (Zea mays L.) IN BANGLADESH

Abstract

Maize is one of the most diverse grain crops and most widely cultivated cereals in the world. Multicolored maize such as yellow, white, red, and purple maize are produced across the Bangladesh. The present study was conducted to observe the amounts of pigments responsible for pericarp color such as phenolics, flavonoids and anthocyanin in six different colored maize varieties using UV-spectrophotometer as a tool. The research was carried out during the time form December 2020 to March 2021 at the Biochemistry laboratory of Department of Biochemistry, and Agro-Environmental Chemistry Laboratory of Department of Agricultural Chemistry, Sher-e-Bangla Agricultural University, Dhaka. In the study, the contents of methanol soluble or free phenolics, acidic methanol soluble or bound phenolics were determined in the whole kernels of six different pigmented and non-pigmented maize such as-yellow maize, red maize, white maize, purple maize, mixed colored maize, deep red maize. In this study, it was observed that the SAU purple maize was rich in phenolics content. It contained 105.82 ± 8.3 mg FAE/100 g sample free phenolics; 165.05 ± 7.5 mg FAE/100 g sample of bound phenolics and 270.87 ± 15.80 mg FAE/100 g sample of total phenolics. SAU purple maize contained the highest flavonoids (76.49 ± 9.5 mg CE/100 g dry weight) and as well as anthocyanins (68.58 ± 5.3 C3G equv./100 f of dry weight sample) among the pigmented and non-pigmented maize varieties. On the other hand, white maize a non-pigmented maize performed the lowest amount of phenolics and flavonoid content. White maize had the amount of 30.55 ± 1.61 mg FAE /100 g of flour in free phenolics, 46.85 ± 4.4 mg FAE /100 g of flour in bound phenolics, and 77.40 ± 5.7 mg FAE /100g of total phenolics content. Total flavonoids content in white maize was 8.82 mg CE /100 g sample dry basis. Yellow maize performed the lowest for total anthocyanin contents 4.7 ± 1.1 mg C3G/100g of sample dry basis. Percentage contribution of insoluble phenolics to total phenolics, and flavonoids to insoluble phenolics was great in the SAU purple maize. Overall, pigmented maize varieties are rich in health beneficial phytochemicals. SAU purple maize showed the great promise for its future usage as human food or as food ingredients. Use of such colored maize in food preparation could add additional immunity to its consumers.