Abstract：
Advanced glycation end products (AGEs), a heterogeneous compound existed in processed foods, are related to chronic diseases when they are accumulated excessively in human organs. Protein-bound Nε-(carboxymethyl) lysine (CML) as a typical AGE, is widely determined to evaluate AGEs level in foods and in vivo. This study investigated the intestinal absorption of three protein-bound CML originated from main food raw materials (soybean, wheat and peanut). After in vitro gastrointestinal digestion, the three protein-bound CML digests were ultrafiltered and divided into four fractions: less than 1 kDa, between 1 and 3 kDa, between 3 and 5 kDa, greater than 5 kDa. Caco-2 cell monolayer model was further used to evaluate the intestinal absorption of these components. Results showed that the absorption rates of soybean protein isolate (SPI)-, glutenin (Glu)-, peanut protein isolate (PPI)-bound CML were 30.18%, 31.57% and 29.5%, respectively. The absorption rates of components with MW less than 5 kDa accounted for 19.91% (SPI-bound CML), 22.59% (Glu-bound CML), 23.64% (PPI-bound CML), respectively, and these samples were absorbed by paracellular route, transcytosis route and active route via PepT-1. Taken together, these findings demonstrated that all three protein-bound CML digests with different MW can be absorbed in diverse absorption pathways by Caco-2 cell monolayer model. This research provided a theoretical basis for scientific evaluation of digestion and absorption of AGEs in food.
摘要：
晚期糖基化终产物（AGEs），加工食品中存在一种异质化合物，当它们在人体器官中过度积累时，与慢性病有关。蛋白质结合的Nε-（羧甲基）赖氨酸（CML）作为典型的AGE，被广泛确定用于评估食物和体内的AGEs水平。本研究调查了三种主要食品原料（大豆，小麦和花生）。体外胃肠消化后，将三个蛋白质结合的CML消化物超滤并分为四个部分：小于1kDa，在1和3kDa之间，在3到5kDa之间，大于5kDa。进一步使用Caco-2细胞单层模型来评估这些组分的肠吸收。结果表明,大豆分离蛋白(SPI)的吸收率,谷蛋白（Glu）-，花生分离蛋白（PPI）结合CML为30.18%，31.57%和29.5%，分别。MW小于5kDa的组分的吸收率占19.91％（SPI结合的CML），22.59%（Glu结合CML），23.64%（PPI绑定CML），分别,这些样本通过细胞旁途径吸收，通过PepT-1的胞吞途径和活性途径。一起来看,这些发现表明，通过Caco-2细胞单层模型，具有不同MW的所有三种蛋白质结合的CML消化物可以在不同的吸收途径中吸收。本研究为科学评价食品中AGEs的消化吸收提供了理论依据。
