Fatty Acids in Dry Beans (Phaseolus vulgaris L.): A Contribution to Their Analysis and the Characterization of a Diversity Panel.

Dry bean (Phaseolus vulgaris L.) is a crop of high nutritional interest widespread throughout the world. This research had two objectives. On the one hand, the development and validation of an analytical method to quantify fatty acids in dry beans based on the extraction and derivatization in a single step and later quantification by gas chromatography. On the other, its application to characterize the fatty acid content in a diversity panel consisting of 172 lines. The method was successfully validated in terms of accuracy, precision and robustness. Among the 14 fatty acids that constitute the fatty acid profile of dry bean, the most quantitatively important were linolenic acid, the major fatty acid in all cases, with an average value of 6.7 mg/g, followed by linoleic acid (3.9 mg/g), palmitic acid (2.9 mg/g) and oleic acid (1.5 mg/g). The concentrations of fatty acids in dry bean were influenced by the gene pool, with the Mesoamerican gene pool showing a higher content of palmitic, stearic, linoleic and linolenic acids and the Andean gene pool a higher level of cis-vaccenic acid. Also, the expression of fatty acid content showed high heritability. The information generated constitutes a robust database of interest in food technology, nutrition and breeding programs.

Phenolic Content and Antioxidant Activity in Seeds of Common Bean (Phaseolus vulgaris L.).

Dry bean (Phaseolus vulgaris L.) is one of the most important pulses consumed in the world. Total phenolic content, total flavonoid content, total monomeric anthocyanin content and antioxidant capacity were determined, using ferric reducing antioxidant power and free radical scavenging activity, in 255 lines grown under the same environmental conditions. For all parameters analysed, there was a wide range of variability, with differences always above one order of magnitude. Phenolic compounds in beans with coloured coats were found to be more efficient antioxidants than those with completely white coats, and samples with more strongly coloured coats (red, cream, black, pink and brown) showed the highest antioxidant capacities. Based on the strong correlation detected between the variables, total phenolic content can be considered an appropriate indicator of antioxidant activity. The results provide a robust database for selecting those lines of greater functional and nutritional interest in terms of cultivation for direct consumption, for inclusions in food formulations or for use in future breeding programs.

Characterization of extractable phenolic profile of common bean seeds (Phaseolus vulgaris L.) in a Spanish diversity panel.

Phenolic compounds are important bioactive compounds in common bean (Phaseolus vulgaris L.). The aim of this work was the characterization of extractable phenolic profile (corresponding to 12 hydroxycinnamic acids and derivatives, 13 anthocyanins and 15 flavonols) in a bean diversity panel constituted by 220 lines, all grown under the same environmental conditions. Hydroxycinnamic derivatives were detected in all samples, while anthocyanins and flavonols were not detected in samples with completely white seed coats. In general, lines with black seeds showed higher contents of anthocyanins, followed by some red-seeded lines, while notable levels of flavonols were detected in market classes, including those with yellow, pink, and cream seed coats. However, a clear relationship between phenolic composition and seed phenotype could not be established, indicating the great influence of the genotype. This wide variability in the phenolic profiles analyzed is of particular interest for further breeding trials and the selection of varieties on the basis of this group of compounds.