Abstract:
The demand and application of functional foods and nutraceuticals as substitutes for synthetic drugs (in the management of diseases, such as type-2 diabetes) has been on the increase in recent years. This study aimed at evaluating the nutritional and phytochemical composition, antioxidant, glycemic response and antidiabetic potential of bread developed from bambara groundnut, orange peel and wheat flour in vitro and in vivo. Bambara groundnuts flour (BGF) and orange peel flour (OPF) were blend together in varying ratios with whole wheat flour (WWF) to obtain the following composite breads: LC (100% WWF without OPF); 0BG (100% WWF+OPF); 10BG (10% BGF+90% WWF); 20BG (20% BGF+ 80% WWF); 25BG (25% BGF+75%WWF); 30BG (30% BGF+70% WWF); 50BG (50% BGF+50% WWF); 75BG (75% BGF+25% WWF); 100BG (100% BGF+0% WWF) and commercial bread sample (CC) was used as control sample. Proximate analysis showed increased total ash, crude fat, fibre and protein, and energy value as well as decreased moisture and carbohydrate contents with increasing bambara groundnut flour content of the composite bread. Similar trends were also observed for minerals and phytochemical compositions. Sensory evaluation of the composite bread samples showed less preference to the CC in aroma, taste and general acceptability due to familiarity of panellist with CC. Antioxidant properties were also observed to increase in the order of percentage of bambara groundnut flour. Furthermore, the composite breads significantly (p<0.05) inhibited key enzymes linked to type-2 diabetes in vitro compared to CC. Interestingly, feeding of diabetic rats with composite bread significantly (p<0.05) reduced elevated blood glucose level, α-amylase and α-glucosidase activities, dyslipidaemia and liver and renal enzymes, and also improved the antioxidant status when compared to CC. All results were observed to be concentration dependent on the percentage inclusion of bambara groundnut in bread composite. These results suggest bambara groundnut could be a good constituent of bread production. In conclusion, the present study observed and seek to recommend developed bread samples, especially those with higher level of bambara groundnut contents, as dietary intervention for type-2 diabetes and its complications management
