Anti-nutrient components and metabolites with health implications in seeds of 10 common bean (Phaseolus vulgaris L. and Phaseolus lunatus L.) landraces cultivated in southern Italy

Common beans (Phaseolus vulgaris L.) provide an inexpensive food rich in macronutrients such as protein and starch, important micronutrients such as iron, and also a number of other stored bioactive compounds (phytates, polyphenols, tannins, raffinosaccharides, lectins, protease and α-amylase inhibitors, saponins, etc.) endowed with positive health implications through their antioxidant, anti-tumour or phyto-oestrogenic activity. They also produce negative dietary effects such as interference with micronutrient absorption, protein digestibility or glucose metabolism, or even direct toxic effects (lectins). Analysis of the levels of these compounds in seeds of local and underexploited common bean varieties and landraces may reveal traits of interest for promoting nutrition and preserving health, and in addition allow breeders to use them in genetic improvement programmes to modify the levels of specific compounds in new common bean varieties. In the present work, 10 bean populations belonging to 7 highly appreciated southern Italian landraces were analysed. The seeds of one of them, “Poverello di Rotonda AF”, was found to accumulate remarkable levels of 4 health-promoting components such as quercetin (24.2 μg/g), genistein (21.6 μg/g), soysapogenin B (433 μg/g) and oleanolic acid (11.9 μg/g), while “Tabacchino” contained very high amounts of iron (131 μg/g) and three health-promoting components: kaempferol (61.0 μg/g), oleanolic acid (12.3 μg/g) and condensed tannins (2.36 mg/g). A level of variation high enough to be exploited for breeding purposes was found for 7 out of 15 biochemical parameters studied.