COMPARATIVE-STUDY OF THE CHEMICAL-COMPOSITION OF WILD AND CULTIVATED BEANS (PHASEOLUS-VULGARIS)

Five wild Phaseolus vulgaris beans were compared with five cultivated Phaseolus vulgaris beans in proximate composition, total (true) protei n, amino acid composition, and toxic and antinutritional factors. The wild beans contained more protein (25.5% vs. 21.7%), ash (5.15 vs. 4.1 5%), crude fiber (7.08% vs. 5.04%) compared to cultivated beans while the former contained less fat (0.56 vs. 0.89%) and carbohydrates (61.6 4 vs. 68.05%). Sulfur amino acids were found to be limiting in both gr oups of bean as expected; however, the cultivated beans had a higher c ontent of the limiting amino acids. Therefore, the cultivated beans sh owed a better amino acid profile than the wild beans. Toxic factors we re not found in either type of bean; the determinations included sapon ins, alkaloids, and cyanogenic glycosides. The antinutritional factors investigated were hemagglutinins (lectins) and trypsin inhibitors. Th e wild beans presented a higher content of trypsin inhibitors (28 TUI per mg) and lectins (9.6) than the cultivated beans did (21 TUI per mg and 7 respectively). From the chemical point of view, domestication s eems to be positive; however, the better protein nutritive quality of the cultivated beans should be further confirmed by biological assays.