Phenolic-rich extracts from toasted white and tannin sorghum flours have distinct profiles influencing their antioxidant, antiproliferative, anti-adhesive, anti-invasive, and antimalarial activities.

ABSTRACT

Sorghum is a gluten-free cereal commonly used in foods, and its consumption has been associated with the prevention of human chronic conditions such as obesity and cancer, due to the presence of dietary fiber and phenolic compounds. This study aimed to evaluate, for the first time, the antiproliferative, antioxidant, anti-adhesion, anti-invasion, and antimalarial activities of phenolic extracts from toasted white and tannin sorghum flours to understand how different phenolic profiles contribute to sorghum biological activities. Water and 70 % ethanol/water (v/v), eco-friendly solvents, were used to obtain the phenolic extracts of toasted sorghum flours, and their phenolic profile was analyzed by UPLC-MSE. One hundred forty-five (145) phenolic compounds were identified, with 23 compounds common to all extracts. The solvent type affected the phenolic composition, with aqueous extract of both white sorghum (WSA) and tannin sorghum (TSA) containing mainly phenolic acids. White sorghum (WSE) and tannin sorghum (TSE) ethanolic extracts exhibited a higher abundance of flavonoids. WSE demonstrated the lowest IC50 on EA.hy926 (IC50 = 46.6 µg/mL) and A549 cancer cells (IC50 = 33.1 µg/mL), while TSE showed the lowest IC50 (IC50 = 70.8 µg/mL) on HCT-8 cells (human colon carcinoma). Aqueous extracts also demonstrated interesting results, similar to TSE, showing selectivity for cancer cells at higher IC50 concentrations. All sorghum extracts also reduced the adhesion and invasion of HCT-8 cells, suggesting antimetastatic potential. WSE, rich in phenolic acids and flavonoids, exhibited greater toxicity to both the W2 (chloroquine-resistant) and 3D7 (chloroquine-sensitive) strains of Plasmodium falciparum (IC50 = 8 µg GAE/mL and 22.9 µg GAE/mL, respectively). These findings underscore the potential health benefits of toasted sorghum flours, suggesting diverse applications in the food industry as a functional ingredient or even as an antioxidant supplement. Moreover, it is suggested that, besides the phenolic concentration, the phenolic profile is important to understand the health benefits of sorghum flours.