In vitro α-amylase and α-glucosidase inhibitory activities, antioxidant activity, in vivo glycemic response and nutritional quality of dough meals from Dioscorea alata and Vernonia amygdalina

In all age groups globally, diabetes is a metabolic disease that is associated with oxidative stress caused by reactive free radicals in the human system. In folklore medicine, plants based diets such as unripe plantain, and water yam are used in management of diabetes. Hence, this study aimed to determine the antioxidant, alpha-amylase and alpha-glucosidase activities, glycemic index, blood glucose concentration and sensory attributes of dough meals developed from flour blends of unripe plantain, water yam and bitter leaf. A remarkable free radical scavenging activity and ferric ion reducing power was observed as the supplementation increased with water yam. The inhibition of alpha-amylase and alpha-glucosidase activities by the dough meal was dependent on the percentage inclusion of water yam and this indicates the antihyperglycemic potential of the dough meal. The glycemic index of rat fed with the dough meal was significantly low at 40% water yam supplementation compared to 100% unripe plantain dough meal. Hence, the study provides a rationale that dough meal from unripe plantain; water yam and bitter leaf have the potential to be used as functional foods to alleviate postprandial hyperglycemia.