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tannins and phytic acid) reduce the bioavailability of Ca, Fe, and Zn (Frossard et al., 2000). In common bean (Phaseolus vulgaris L.), some nutritional traitsDuring the past 25 yr, substantial progress has been such as proteins and mineral content are lower in the cultivated form as compared with the wild counterpart. To assess the feasibility of made on the clinical, biochemical, and immunological wild bean as the putative source of desirable traits such as minerals aspects of the role of Zn in humans (Ganapathy and or tannins, this study was performed to identify quantitative trait loci Volpe, 1999). Extensive research has shown that Zn is (QTL) associated with seed mass, Ca, Fe, Zn, and tannin content in involved in a myriad of critical reactions in the human bean seed. Two-hundred-ninety-one amplified fragment length polybody and is associated with cellular growth and repair, morphism (AFLP) markers were scored in 120 F 2:3 segregating individappetite, behavior, and susceptibility to infection. Reuals derived from a cross between cultivated 'Bayo Baranda' and cent studies have identified Zn deficiencies in children wild common bean accession G-22837. Seed weight and minerals and who consume diets high in cereals (Ranum, 1999). tannin contents were quantified on the seed harvested from the 120 individual plants. Significant transgressive segregation was observed Moreover, it is recognized that a nutritional deficiency among the F 2:3 individuals for some characteristics. A total of 57 AFLP in Zn is common throughout the world, including the markers were distributed among five linkage groups with a coverage USA. (Ganapathy and Volpe, 1999). of 497 centiMorgans (cM). Five putative QTL were significantly asso-Plant breeding has been mainly focused on increasing ciated with seed mass, two with Ca, two with Fe, one with Zn, and yield and disease resistance in crops, but not at improvfour with tannin content in the seed. These QTL explained ≈42, 25, ing the micronutrient concentration in grain (Frossard 25, 15, and 42% of the phenotypic variance, respectively. Due to et al., 2000). Developing cultivars with higher capacity known environmental effect on most nutritional traits, the use of QTL to accumulate Ca, Fe, and Zn could contribute signifiwith larger effects could be used to screen segregating populations cantly to the improvement of the micronutrient status that include wild genotypes, wild populations, and ancestral landraces from the region where outstanding wild populations are identified.

Xoconostle cv. Cuaresmeño (Opuntia matudae) has attracted domestic and international industry attention; however, variations of composition from xoconostle structures have not been evaluated. Industries discard the pulp (endocarp) and peel (pericarp) as wastes and utilize the skin (mesocarp), which is the edible portion. The physicochemical, nutritional, and functional characterization of structures from xoconostle pear from 3 major sites of production in Mexico were assessed. Skin yield ranged from 58% to 64% and was higher to that of peel (22% to 24%) and pulp (12% to 18%) yields. pH, degrees Brix, and acidity were similar among xoconostle structures. Total fiber showed by peel (18.23% to 20.37%) was 2-fold higher than that of skin. Protein and ether extract were higher in xoconostle pulp compared to that showed by peel and skin. Iron content of xoconostle peel (6 to 9.6 mg/100 g, DWB) was higher to that of skin and pulp and prickly pear pulp. Soluble phenols of peel (840 to 863 mg GAE/100 g, DWB) were almost similar to that of skin (919 to 986 mg GAE/100 g, dry weigh basis); meanwhile, ascorbic acid concentration of skin was 2-fold higher compared to that of peel. The phenolic fraction of xoconostle structures consisted of gallic, vanillic, and 4-hydroxybenzoic acids; catechin, epicatechin, and vanillin were also identified by high-performance liquid chromatography-didoe array detection (HPLC-DAD). Xoconostle peel showed higher antioxidant activity (TEAC) compared to that of skin (2-fold) and pulp (6-fold) of commonly consumed fruits and vegetables. The potential of xoconostle peel and pulp for the production of feed or food is promissory. Practical Application: Outstanding nutritional and functional properties of xoconostle cv. Cuaresmeño fruits are demonstrated. Increased consumption could contribute positively to improve the diet of rural and urban consumers. The high fiber, mineral, and antioxidant components of xoconostle peel and pulp suggest that these fruit structures, which are currently discarded as waste, have promissory use as feed or food by industry.

Trypsin inhibitors (TI), tannins, and lectins appear to have a role in preventing chronic diseases in humans. The genetic variability of these traits in common bean needs to be ascertained in order to increase levels through breeding. The variability of TI, tannin, and lectins was determined in five bean cultivars grown at five locations in Mexico. TI and tannins contents in colored beans that belong to the Jalisco race were higher (11.1-11.9 trypsin units inhibited (TUI)/mg and 29.0-38.1 mg catechin equivalent (CE)/g, respectively) than cultivars of the Durango race (7.9-8.3 TUI/mg and 16.8-19.9 CE/mg, respectively). Bayo Victoria, a Durango race cultivar, had three times more lectins than levels reported for soybean. Cultivar influenced TI and tannins contents (p < 0.001), whereas site affected lectins (p < 0.001). An increase in levels of TI and tannins could be enhanced through breeding.