Nutritional and bioactive characteristics of Ayocote bean (Phaseolus coccienus L.): An underutilized legume harvested in Mexico

Nutritional composition, content of phenolic compounds and antioxidant properties of the four Mexican varieties of Ayocote beans (Phaseolus coccineus L.) were studied. Ayocote beans were found to be a promising source of proteins, carbohydrates, fibre and minerals. Sucrose (55.6-62.2 g/kg) and stachyose (24-24.4 g/kg) were considered as the major sugar and oligosaccharide, respectively. Glutamic acid was the most abundant amino acid (32.2 to 35.8 g/kg), while cysteine was present at the lowest concentration (2.3-2.4 g/100 kg). Purple variety contains the highest amount of total phenolic compounds (2075.9 mg GAE/kg), total flavonoids (1612.9 mg QE/kg) and total anthocyanins (1193.2 mg CGE/kg). This variety also exhibited the most effective antioxidant activities, which were evaluated by DPPH (17,040 mu mol TE/kg) and ORAC (51,620 mu mol TE/kg). The results obtained reveal a high potential for wider use of Ayocote bean as a remarkable source of bioactive compounds and health-promoting food. RESUMENSe estudiaron la composicion nutricional, contenido de compuestos fenolicos y propiedades antioxidantes de cuatro variedades de Ayocote (Phaseolus coccineus L.) mexicano. Dicho cultivo mostro ser una buena fuente de proteinas, carbohidratos, fibra y minerales. La sacarosa (55.6-62.2 g/kg) y estaquiosa (24-24.4 g/kg) se identificaron como los principales azucar y oligosacarido, respectivamente. En cuanto a aminoacidos, el acido glutamico (32.2-35.8 g/kg) y la cisteina (2075.9 mg GAE/kg), son el de mayor y menor abundancia, respectivamente. En la variedad morada se cuantificaron las mayores concentraciones de compuestos fenolicos totales (2075.9 mg GAE/kg), flavonoides totales (1612.9 mg QE/kg) y antocianinas totales (1193.2 mg CGE/kg), asi como presentar la mayor actividad antioxidante evaluandose por DPPH (17,040 mu mol TE/kg) y ORAC (5162 mu mol TE/kg). Los resultados obtenidos revelan un alto potencial para un uso mas amplio del frijol Ayocote como una fuente prometedora de compuestos bioactivos y alimentos que promueven la salud.