Shannon Applied Biotechnology Centre, Institute of Technology Tralee, Tralee, Ireland.
Marigot Ltd., Carrigaline, Ireland.
J Nutr Sci. 2021 Jan 12;10:e5. doi: 10.1017/jns.2020.56. eCollection 2021.
Type II diabetes is considered the most common metabolic disorder in the developed world and currently affects about one in ten globally. A therapeutic target for the management of type II diabetes is the inhibition of α- glucosidase, an essential enzyme located at the brush border of the small intestinal epithelium. The inhibition of α-glucosidase results in reduced digestion of carbohydrates and a decrease in postprandial blood glucose. Although pharmaceutical synthetic inhibitors are available, these are usually associated with significant gastrointestinal side effects. In the present study, the impact of inhibitors derived from edible brown algae is being investigated and compared for their effect on glycaemic control. Carbohydrate- and polyphenolic-enriched extracts derived from , and were characterised and screened for their inhibitory effects on maltase and sucrase enzymes. Furthermore, enzyme kinetics and the mechanism of inhibition of maltase and sucrase were determined using linear and nonlinear regression methods. All tested extracts showed a dose-dependent inhibitory effect of α-glucosidase with IC values ranging from 0⋅26 to 0⋅47 mg/ml for maltase; however, the only extract that was able to inhibit sucrase activity was , with an IC value of 0⋅83 mg/ml. The present study demonstrates the mechanisms in which different brown seaweed extracts with varying composition and molecular weight distribution differentially inhibit α-glucosidase activities. The data highlight that all brown seaweed extracts are not equal in the inhibition of carbohydrate digestive enzymes involved in postprandial glycaemia.
2 型糖尿病被认为是发达世界最常见的代谢紊乱疾病，目前全球约有十分之一的人受到影响。2 型糖尿病管理的治疗靶点是抑制位于小肠上皮刷状缘的必需酶α-葡萄糖苷酶。α-葡萄糖苷酶的抑制作用导致碳水化合物消化减少，餐后血糖降低。虽然有药用合成抑制剂，但这些抑制剂通常与严重的胃肠道副作用有关。在本研究中，正在研究来自食用褐藻的抑制剂的影响，并比较它们对血糖控制的影响。从 、 和 中提取的富含碳水化合物和多酚的提取物进行了表征，并筛选其对麦芽糖酶和蔗糖酶的抑制作用。此外，使用线性和非线性回归方法确定了麦芽糖酶和蔗糖酶的酶动力学和抑制机制。所有测试的提取物均表现出对α-葡萄糖苷酶的剂量依赖性抑制作用，麦芽糖酶的 IC 值范围为 0.26 至 0.47 mg/ml；然而，唯一能够抑制蔗糖酶活性的提取物是 ，其 IC 值为 0.83 mg/ml。本研究表明，具有不同组成和分子量分布的不同褐藻提取物通过不同的机制抑制α-葡萄糖苷酶活性。数据表明，并非所有褐藻提取物在抑制与餐后血糖有关的碳水化合物消化酶方面都是平等的。
