Oral Complex Carbohydrate Sensing

总结 碳水化合物在人类饮食中起着重要作用，其消费程度直接影响 人体健康为了控制碳水化合物的消耗，了解味觉系统是如何 回应他们。最近，我们报道说，人类可以品尝葡萄糖基寡糖， 检测不依赖于已知的甜味受体。在这些调查结果的基础上，本提案力求 建立人类可以品尝的寡糖范围，并进一步确定其结构 低聚糖的特性使其能够被人类感知。该项目有两个主要的 假设：（1）人类可以品尝各种各样的寡糖，（2）味觉检测取决于 对寡糖分子结构中单体结构单元、链 糖苷键的长度、位置和数目以及末端残基。这两个假设将被检验 通过使用一系列天然存在的、明确定义的寡糖和选定的衍生物。两个功能上 将考虑不同组的低聚糖：（a）淀粉衍生的可消化的低聚糖， 膳食能量的主要来源和（B）不被人类消化但 被认为有益于健康（例如，益生元）。认识到市售低聚糖 通过使用具有不确定轮廓的异质“鸡尾酒”，我们提出纯化或分离目标寡糖。 因此，该项目的一个重要的额外成果将是可供使用的协议， 制备用于人体测试的定义明确的天然和衍生寡糖。这些化合物 应该证明是有价值的候选配体，为未来的研究，旨在分子表征 寡糖受体。

SUMMARY Carbohydrates play a significant role in the human diet and the extent of their consumption directly impacts human health. In order to control carbohydrate consumption, it is critical to understand how the gustatory system responds to them. Recently, we reported that humans can taste glucose-based oligosaccharides and that their detection is independent of the known sweet receptor. Building upon these findings, this proposal seeks to establish the range of oligosaccharides that humans can taste and further to determine the structural characteristics of oligosaccharides that enable their perception by humans. This project has two overarching hypotheses: (1) that humans can taste a wide range of oligosaccharides, and (2) that taste detection depends on the molecular structures of oligosaccharides with respect to the types of monomer building blocks, chain length, position and number of glycosidic linkages, and terminal residues. These two hypotheses will be tested by using a range of naturally existing, well-defined oligosaccharides and selected derivatives. Two functionally different groups of oligosaccharides will be considered: (a) starch-derived digestible oligosaccharides that are primary sources of dietary energy and (b) non-starch oligosaccharides that are not digested by humans but are considered beneficial to health (e.g., prebiotics). Recognizing that commercially available oligosaccharides are heterogeneous “cocktails” with undefined profiles, we propose to purify or isolate target oligosaccharides. Accordingly, an important additional outcome of this project will be publically available protocols for the preparation of well-defined, natural and derivatized oligosaccharides for human testing. These compounds should prove to be valuable candidate ligands for future studies aimed at the molecular characterization of oligosaccharide receptor(s).