Abstract：
In the current study, how pectin retards the digestibility of wheat gluten was investigated using a static in vitro gastric-duodenal model. The degree of protein hydrolysis was estimated using the o-phthaldialdehyde method, while the in vitro digestograms were mathematically fitted using a single first-order kinetics model. Peptides\' profile, free amino acids compositions, gluten-pectin interactions and their effects on enzymatic activities of proteolytic enzymes as well as on the gluten secondary structures under digestive conditions were studied using combined techniques. Results showed that pectin could retard gluten digestibility through 1). preferential absorption to insoluble gluten aggregates by electrostatic interactions; 2). increasing the helix and reducing the β-sheet content of the solubilized gluten protein fractions in terms of their secondary molecular structures; 3). reducing pepsin activity by forming negatively charged pectin-gluten mixtures which then interacted with the positively charged pepsin molecules. The deeper insight into gluten-pectin interactions and their influences on gluten digestibility under gastrointestinal conditions provides important clues for developing effective forms of dietary fiber to improve the nutritional benefits of plant protein in individuals.
摘要：
在目前的研究中,使用静态体外胃十二指肠模型研究了果胶如何延缓小麦面筋的消化率。使用邻苯二醛方法估计蛋白质水解程度，而体外消化图使用单个一阶动力学模型进行数学拟合。肽简介，游离氨基酸成分，使用组合技术研究了谷蛋白-果胶相互作用及其对蛋白水解酶的酶活性以及在消化条件下对谷蛋白二级结构的影响。结果表明，果胶可以通过1）延缓面筋的消化率。通过静电相互作用优先吸收不溶性面筋聚集体；2）。就其二级分子结构而言，增加螺旋并减少溶解的谷蛋白级分的β-折叠含量；3）。通过形成带负电荷的果胶-面筋混合物，然后与带正电荷的胃蛋白酶分子相互作用来降低胃蛋白酶活性。更深入地了解谷蛋白-果胶相互作用及其在胃肠道条件下对谷蛋白消化率的影响，为开发有效形式的膳食纤维以改善个体植物蛋白的营养益处提供了重要线索。
