https://doi.org/10.17113/ftb.56.03.18.5540 

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

Lei Feng^§, Yufeng Xie^§, Chenmiao Peng, Yuxiaoxue Liu and Haikuan Wang*

State Key Laboratory of Food Nutrition and Safety, College of Biotechnology, Tianjin University of Science and Technology, No. 29 of 13th Avenue, Tianjin, PR China

Article history:
Received: 28 September 2017
Accepted: 15 May 2018 

Key words:
Tartary buckwheat, fermentation, α-glucosidase inhibition, dipeptidyl peptidase IV inhibition, antidiabetic

Summary:
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 Lactobacillus plantarum TK9 and L. paracasei TK1501. The results of an orthogonal experimental design indicated that the three factors with the largest effects on the growth of L. plantarum TK9 and L. paracasei 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 10⁷ CFU/g inoculum, the Tartary buckwheat fermented by L. plantarum TK9 and L. paracasei TK1501 yielded viable probiotic counts of (2.3±0.7)·10⁹ and (3.3±0.4)·10⁹ 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 IC₅₀ of 0.51 mg/mL, was present in Tartary buckwheat fermented by L. plantarum TK9. However, Tartary buckwheat fermented by L. paracasei TK1501 had the highest dipeptidyl peptidase IV (DPP-IV) inhibition, with an IC₅₀ of 2.47 mg/mL. Therefore, fermentation by both L. plantarum TK9 and L. paracasei TK1501 has the potential to yield a product that can help regulate the levels of blood glucose as part of a diabetic diet.

*Corresponding author:  +862260601958
                                           +862260602298
                                            hkwang@aliyun.com

^§These authors contributed equally to this work