Antinutritional factors in legumes of the Sonoran Desert

Abstract

Ten samples of legumes indigenous to the Sonoran Desert were analyzed for antinutritional factors: flatulent oligosaccharides, trypsin inhibitors, lectins, phytic acid and cyanogenic glycosides. These samples represented the following species: Phaseolus acutifolius var. latifolius. Phaseolus vulgaris, Lysiloma watsonii and Parkinsonia aculeata. The raffinose and stachyose contents of the beans ranged from 0.00–3.57 percent and 0.00–5.45 percent respectively. The trypsin inhibitor (TI) activities ranged from 2.3–60.4 TIU/mg; heat treatment decreased TI activity from 0–97 percent. Phytic acid ranged from 0.48–1.02 percent. Cyanogenic glycosides were not detected in any of the samples. Lectin extracts from all of the legume samples agglutinated rabbit, hamster and bovine red blood cells. Reduction of hemagglutinating activity upon heat treatment ranged from 0–100 percent.