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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 Ϯ 0.072 mgGA/100 mg, while A. hybridus was found to have the least phenolic compound concentration of 1.127 Ϯ 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

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SummaryThe phenolic compound content and profiles of three wild fruits found in Zimbabwe were tentatively identified using the traditional colorimetric methods and high-performance liquid chromatography (HPLC). The fruits assayed were: Ximenia caffra, Artobotrys brachypetalus and Syzygium cordatum. Ximenia caffra fruit peels contained the highest amounts of total phenolics amounting to 1205 lg g)1 in fresh weight, flavonols amounting to 27 lg g )1 and phenolic acids on HPLC tentative identification showed higher concentrations compared with the profiles of the other fruits. Syzygium cordatum fruit peels contained the least amounts of phenolics amounting to 20 lg g)1, flavonols amounting to 8 lg g )1 and phenolic acids' HPLC profiles showed low concentrations. Comparing the peels and pulps of all the fruits, we detected more total phenolics in the peels of X. caffra as high as 1205 lg g )1 and the pulps had 228 lg g)1, more flavonols and phenolic acids while the peels of S. cordatum fruits contained the least with a total phenolic acid content of 20 lg g )1, and had more flavonols in the pulps than the peels, 11 lg g)1 and 8 lg g)1, respectively. Ximenia caffra contained 1.2% and about 1% dry weight condensed tannins in peels and pulps, respectively. In S. cordatum we detected 0.2% and 0.3% dry weight condensed tannins in the peels and pulps, respectively.

Four wild fruits, Diospyros mespiliformis, Flacourtia indica, Uapaca kirkiana and Ziziphus mauritiana, were extracted with methanol and analysed for radical-scavenging effect of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, reducing power and anion radical effect on superoxide anion using colorimetric method. There was an increase in the radical-scavenging effect, reducing power and superoxide anion radical-scavenging effect as the concentration of sample increased. Diospyros mespiliformis had high DPPH radical-scavenging capacity. The peels of F. indica and U. kirkiana had higher DPPH radical-scavenging effects, reducing power and superoxide-scavenging effects compared with the pulp while the pulp of Z. mauritiana had high DPPH radical-scavenging effects, reducing power and superoxide-scavenging effects compared with the peel.