Inhibitory potential of prickly pears and their isolated bioactives against digestive enzymes linked to type 2 diabetes and inflammatory response

BACKGROUND Prickly pears are potential candidates for the development of low-cost functional foods because they grow with low water requirements in arid regions of the world. They are sources of betalains and phenolic compounds, which have been reported to contribute to human health. The study of the biological activity of different varieties and of their isolated bioactive constitutes is fundamental in the design of functional foods. In this context, our objective is the assessment of the ability of Spanish and Mexican prickly-pear cultivars to inhibit enzymes related to type 2 diabetes and the inflammatory response, and the contribution of their bioactive compounds to their nutra-pharmaceutical potential. RESULTS Prickly pear peels presented the highest antioxidant activity due to their high isorhamnetin glycoside content. Isorhamnetin glycosides showed significantly higher antioxidant and anti-inflammatory activity than aglycone, particularly isorhamnetin glucosyl-rhamnosyl-pentoside (IG2), which also reported antihyperglycemic activity. Morada, Vigor, and Sanguinos whole fruits exhibited moderate alpha-amylase inhibition and higher alpha-glucosidase inhibition, which is ideal for lowering glucose absorption in hyperglycemia management. Sanguinos peels presented the highest anti-inflammatory activity because of their high indicaxanthin content and isorhamnetin glycoside profile. CONCLUSIONS In the design of prickly pear functional foods, technological processing should prioritize the retention or concentration of these bioactive compounds to preserve (or increase) their natural antioxidant, antihyperglycemic and anti-inflammatory activity. Peels of red and orange varieties should be further evaluated for antioxidant and anti-inflammatory purposes while whole fruits of red and purple varieties could be considered possible candidates for hyperglycemia management. (c) 2019 Society of Chemical Industry