PHENOLIC COMPOUND CONTENT, PROFILES AND ANTIOXIDANT ACTIVITIES OF AMARANTHUS HYBRIDUS (PIGWEED), BRACHIARIA BRIZANTHA (UPRIGHT BRACHIARIA) AND PANICUM MAXIMUM (GUINEA GRASS)

Amaranthus hybridus, Brachiaria brizantha and Panicum maximum are wild cereal grains that have been consumed mainly in times of drought especially in the Manicaland Province, which is the worst-hit province in Zimbabwe whenever there are droughts. Methanolic extract solutions were prepared from sun-dried A. hybridus, B. brizantha and P. maximum grains. We studied the phenolic compound content and antioxidant properties including high-performance liquid chromatography, 1-diphenyl-2-pierylhydrazyl radical scavenging and reducing power. B. brizantha was found to contain the highest phenolic compound concentration of 3.180 ± 0.072 mgGA/100 mg, while A. hybridus was found to have the least phenolic compound concentration of 1.127 ± 0.133 mgGA/100 mg. The grains were found to contain caffeic acid, ferulic acid, p-coumaric acid, p-hydroxybenzoic acid and protocatechuic acid. P. maximum had the highest DPPH scavenging capacity and the highest reducing power as well. A. hybridus had the least reducing power and required 20.33 mg of sample equivalent per milliliter to reduce Fe 3+ to Fe 2+ .