comparative phytochemical, nutritional and antimicrobial screening of the seed, leaf and root of vigna subterranea.

Vigna subterranea, a legume regarded as a ‘super food’ in nigeria has been grossly understudied and underutilised and this study investigated the constituents of the various parts of this plant for possible utilization. the seed, leaf and root of the plant were analyzed to assay the phytochemical constituents using standard gravimetric methods, nutritional and amino acid constituents using both gravimetric and spectroscopic as well as the antimicrobial activities using agar well diffusion method. the quantitative phytochemical analysis showed high percentage content of alkaloids (0.34 ±0.02), flavonoids (0.373 ± 0.01) and tannins (0.327±0.013) on the leaf followed by the root with the highest saponins content (0.433 ± 0.02). steroids were found in moderate quantities on all tested parts. the nutritional analysis showed high protein content on all the parts. the leaf had the highest vitamin c content (6.453mg/100g) while vitamin b3 was found to be highest in the seeds(2.123mg/100g) the total essential amino acids (g/100g) in seed, leaf and root were 42.44, 39.85, and 30.82 respectively, while total non-essential amino acids (g/100g) were 50.05, 46.84, and 38.25 respectively. the antimicrobial analysis showed n-hexane extract of the root having the highest activity against pseudomonas aeruginosa (24 ± 1.41 mm zone of inhibition). the minimum inhibitory concentration (mic) for n-hexane extract was 100 mg/l while the minimum bacterial concentration (mbc) was 200 mg/l. indicates a good antimicrobial agent. the leaf and root of vigna subterranea can no longer be regarded as post -harvest wastes but potential sources of drugs and nutrients.