Mixture design approach for the compositional optimization of cereal grain and legume toward improved biological activity

Abstract

Whole grain and legume are increasingly recommended as part of a healthy diet due to their beneficial properties. Blending these seeds can enhance their overall bioactivity. However, optimal mixing ratios remain to be determined. This study aimed to determine the optimal blend ratio of cereal grain and legume with enhanced biological activity using a mixture design approach. Three seed cultivars–sorghum (cv. Goeunchal), Italian millet (cv. Samdachal), and black soybean (cv. Soman)–were selected for their distinct compositional characteristics and potential lipase inhibitory activities. An optimal mixture was identified through response surface modeling, targeting maximized lipase inhibitory activity, along with improved antioxidant activity and extraction yield, and was validated by experimental confirmation. Compositional analyses revealed that Soman was rich in constituent amino acids and omega-3 fatty acids, Samdachal exhibited favorable lipid indices with low atherogenicity and thrombogenicity, and Goeunchal demonstrated superior protein efficiency and antioxidant potential. The optimized blend (64.415 % Goeunchal, 18.535 % Samdachal, and 17.050 % soman) exhibited a harmonized nutritional profile, with balanced amino acid composition and improved lipid quality. Compared to Samdachal, the optimized blend exhibited 26.39- and 1.45-fold higher DPPH radical scavenging and lipase inhibitory activities, respectively. These findings demonstrate that mixture design optimization can effectively integrate the complementary traits of individual seeds and produce a functionally enhanced seed blend with potential applications in health-promoting food applications.