Value and characterization of Cabo Verde Leguminosae plants as sources of new foods

Abstract

Legume species are important food sources to prevent starvation, under-, and malnutrition; they also play a crucial role in sustainable agriculture in the tropical dry islands of Cabo Verde. In order to improve the knowledge of the heritage of plant genetic resources in Cabo Verde, namely of the Leguminosae family, this study had three main goals: i) to provide a checklist of Leguminosae taxa used as food; ii) to investigate which legume species are consumed and traded in local markets and to compare species for their chemical composition and nutritional value; and iii) to discuss aspects concerning the agronomic value, sustainable use of legumes, and their potential contribution to food security in this archipelago. Results revealed that 15 Leguminosae species are used as food and all but one is cultivated. Five of these species are widely consumed/traded in local markets, namely: Cajanus cajan, Lablab purpureus, Phaseolus lunatus, Phaseolus vulgaris, and Vigna unguiculata. Regarding the nutritional value, Lablab purpureus, Phaseolus vulgaris and Vigna unguiculata present about 23% of protein. Cajanus cajan and Lablab purpureus showed the highest antioxidant capacities, fibre and phenolic contents; Phaseolus vulgaris showed the highest ash and moisture contents. The highest mineral content was found for the following elements and species: Cu, in Cajanus cajan; Mg, and Mn, in Lablab purpureus; K, Ca, P, and Fe in Phaseolus vulgaris; and Mg, S, and Zn in Vigna unguiculata. The role of these species as sources of nutrients for food security is highlighted, and the native ones (Lablab purpureus and Vigna unguiculata) stand-out as particularly well-adapted to the adverse climate of these islands. The present study allowed concluding that the conservation and sustainable use of these plant genetic resources can contribute to the reduction of hunger and poverty, thus meeting some challenges of the Sustainable Development Goals (zero hunger, good health and well-being and climatic action).