Nutraceutical components, antioxidant activity and color of eleven varieties of prickly pear (<i>Opuntia</i> sp.)

Abstract

In Mexico, there are 50 recorded varieties of the prickly pear fruit. National production covers only the white-pulp fruit, but other red varieties have export potential; however, their nutraceutical properties are unknown. The pulp and peel (underutilized tissue) of the pigmented fruits of the genus Opuntia sp. are marketed on a limited basis. They represent an alternative source of stable pigments (betalains), which are associated with antioxidant properties, for the agroindustry. The objective was to assess the content of nutraceutical components, antioxidant activity, and peel and pulp color of 11 varieties of the prickly pear fruit that are marketed on a small scale. Statistical analysis revealed that Roja Villanueva peel had the highest betalain content (39.97 mg 100 g-1 FW). Alteña Blanca peel demonstrated the highest concentration of phenolic compounds (618.39 mg GAE 100 g-1 FW), whereas Alteña Roja had the highest ascorbic acid content (37.14 mg AAE 100 g-1 FW). The greatest nutraceutical potential was observed in the pulp of the non-marketed Tzaponopal Rojo variety of the species O. robusta var. larreyi, due to the high antioxidant activity (0.0183 mg mL-1), as well as the darkest color (‹ hue value, 12.31) and the lowest lightness (‹ luminosity, 19.31), which coincides with the highest betalain concentration.