A Novel Antidiabetic Food Produced Solid-State Fermentation of Tartary Buckwheat by TK9 and TK1501.

Diabetes is a chronic metabolic disease characterized by hyperglycaemia and a number of potential complications that significantly reduce the patient's quality of life. In this study, we produced an antidiabetic functional food from Tartary buckwheat fermented by TK9 and TK1501. The results of an orthogonal experimental design indicated that the three factors with the largest effects on the growth of TK9 and TK1501 in solid-state fermentation (SSF) were in the order: water ratio>inoculum size>time of fermentation. Under the optimal fermentation conditions comprising a 1:1.5 water ratio, 24 h of SSF and a 10 CFU/g inoculum, the Tartary buckwheat fermented by TK9 and TK1501 yielded viable probiotic counts of (2.3±0.7)·10 and (3.3±0.4)·10 CFU/g, respectively. The nutritional potential, as well as antioxidant and antidiabetic properties of ethanolic extracts from fermented Tartary buckwheat were investigated. The highest α-glucosidase inhibitory activity, with an IC of 0.51 mg/mL, was present in Tartary buckwheat fermented by TK9. However, Tartary buckwheat fermented by TK1501 had the highest dipeptidyl peptidase IV (DPP-IV) inhibition, with an IC of 2.47 mg/mL. Therefore, fermentation by both TK9 and TK1501 has the potential to yield a product that can help regulate the levels of blood glucose as part of a diabetic diet.