青刺果粕肽饼干的品质、消化特性和降糖潜能

Quality, Digestive Properties, and Hypoglycemic Potential of Prinsepia utilis Royle Meal Peptide Biscuits

摘要:

模拟胃肠消化结合超滤制备分子量>5 ku和<5 ku的青刺果粕肽PMPa（Prinsepia utilis Royle meal peptide>5 ku）和PMPb（Prinsepia utilis Royle meal peptide<5 ku），分析它们的降糖和抗氧化活性，研究肽的添加量为0、1.25%、2.5%、5.0%和7.5%饼干的颜色和质构，模拟消化后饼干快速消化淀粉（RDS）含量、慢性消化淀粉（SDS）含量、血糖负荷（GL）以及对Ⅱ型糖尿病小鼠餐后2 h血糖水平。PMPa和PMPb的α-淀粉酶抑制率分别为62.33%和68.51%，且显著高于阿卡波糖，PMPb对白蛋白抑制率和DPPH自由基清除率均显著高于PMPa和阳性对照双氯酚酸钠、维生素E；随肽添加量的增加，饼干的亮度、硬度和咀嚼度逐渐降低，饼干消化后RDS含量减少、SDS含量增加；且添加7.5% PMPa和PMPb的饼干具有最低的血糖负荷，分别为15.57和13.79，属于中等GL食物；高比例PMP（5.0%和7.5%）替代的饼干饲喂II 型糖尿病小鼠后2 h餐后血糖（2 h Postprandial Blood Glucose, 2 h PBG）显著低于对照组。综上，PMP的添加可以改善小麦饼干的体外消特性并在一定程度上调控餐后血糖水平，其活性特征可作为天然活性食品配料应用于健康饼干。

Abstract:

Simulated gastrointestinal digestion combined with ultrafiltration was used to prepare peptides PMPa (Prinsepia utilis Royle meal peptide>5 ku) and PMPb (P. utilis Royle meal peptide<5 ku) with different molecular weights, and their hypoglycemic and antioxidant activities were analyzed. The added amounts of the studied peptides were 0%, 1.25%, 2.5%, 5.0%, and 7.5% biscuits. The color and texture of the biscuits simulate the rapidly digestible starch (RDS) content; chronically digestible starch (SDS) content; blood glucose load (GL); and 2 h postprandial blood glucose levels in type 2 diabetic mice after digestion. The α-amylase inhibition rates of PMPa and PMPb were 62.33% and 68.51%, respectively, which were significantly higher than those of acarbose. The albumin inhibition rate and 2,2-diphenyl-1-picrylhydrazyl free radical scavenging rate significantly higher for PMPb than PMPa and the positive control diclofenac sodium., vitamin E. As the amount of added peptide increased, the brightness, hardness, and chewiness of the biscuits gradually decreased, the RDS content decreased, and the SDS content increased after the biscuits were digested. Moreover, biscuits with 7.5% PMPa and PMPb added had the lowest glycemic loads of 15.57 and 13.79, respectively, which indicate that they are medium GL foods. The 2 h postprandial blood glucose concentration was significantly lower in type II diabetic mice fed biscuits with high proportions of PMP (5.0% and 7.5%) than in control mice. In summary, the addition of PMP can improve the in vitro digestion properties of wheat biscuits and regulate postprandial blood sugar levels to a certain extent. Owing to its dynamic attributes, PMP can be applied as a natural active food ingredient in nutritious biscuits.