High-density branched α-amylase hydrolyzates from α-glucans exhibit distinct glucose and appetite-regulatory...

This study explored a production strategy for α-amylase hydrolyzates through enzymatic synthesis and modification of carbohydrates, and evaluated their slow digestibility and positive metabolic effects in the mammalian digestive tract, particularly regarding blood glucose regulation, hormone responses, and appetite control. This material exhibited a high α-1,6 linkage ratio (17.7 ± 0.2%) and larger molecular size (0.55 × 10⁷ g mol^-1) compared to α-amylase hydrolyzates from enzymatically synthesized/modified starches and α-glucans. This unique structure enabled it to largely bypass α-amylolysis and be degraded primarily by the small intestinal α-glucosidase complex, resulting in a significantly slower hydrolysis rate to glucose, approximately 42% lower than that of the rapidly digestion control. This material suppressed the initial postprandial glucose spike by up to 65% compared to rapidly digestible control and extended the glycemic response in a mouse model, while the gradual increase in blood glucose also moderated insulin levels and prevented excessive secretion. Additionally, the prolonged glucose release throughout the small intestine stimulated ileal L-cells to significantly increase peptide tyrosine tyrosine (PYY) secretion, while long-term consumption of this material promoted anorexigenic neuropeptide, contributing to sustained appetite suppression. Consequently, the strategy of producing α-amylase hydrolyzates with significantly reduced α-1,4 linkages hold great potential as a functional ingredient for preventing metabolic disorders, such as obesity and type 2 diabetes, caused by impaired glycemic and hormonal homeostasis due to rapidly increasing glycemic responses.