Bioactive components, enzymes inhibitory and antioxidant activities of biofortified yellow maize (Zea mays L.) and cowpea (Vigna unguiculata L. Walp) composite biscuits

Abstract

This study evaluated the bioactive components, enzymes inhibitory and antioxidant activities of biofortified yellow maize (YM) and cowpea (CP) composite biscuits. Composites of YM and CP, mixed at the ratios of 100:0 (YM); 75:25 (YMCP-1); 50:50 (YMCP-2); 25:75 (YMCP-3) and 0:100 (CP), were used to bake composite biscuits designated YM-B, YMCP-1B, YMCP-2B, YMCP-3B and CP-B, respectively. Refined wheat flour (WT) served as the control biscuit (WT-B). The bioactive components (total carotenoids, total phenolics, tannins, total flavonoids and total saponins), enzymes (pancreatic lipase, α-amylase, α-glucosidase) inhibitory and antioxidant (ABTS*+, DPPH* scavenging and reducing power) activities of the flours and biscuits were determined. Total carotenoids content increased significantly (p < 0.05) with increasing proportion of YM, while total phenolics, tannins, total flavonoids and saponins contents, enzymes inhibitory and antioxidant activities increased with increasing proportion of CP in the composite flours and biscuits. Among the composite biscuits, YMCP-3B had the strongest (p < 0.05) enzymes inhibitory and antioxidant activities. The composite biscuits, especially YMCP-3B, may serve as functional biscuits for retarding the rate of fatty acids and glucose formation, and mitigating oxidative stress, which represent a clinical strategy for managing obesity and type 2 diabetes.