通过计算方法预测甜菊糖苷的甜味和苦味

Prediction of Sweetness and Bitterness of the Steviol Glycosides by Computational Approach

摘要:

通过计算模拟软件，对一系列甜菊糖苷与人体味觉受体间的相互作用进行了研究。建立了人体甜味受体（hT1R2，hT1R3）和苦味受体（hT2R4）的同源模型，通过Ramachandran图和其他质量参数来验证模型的可靠性。将味觉受体模型与天然甜菊糖苷分子进行对接，分析了对接过程中的能量变化和相互作用，发现对接结果与甜菊糖苷的甜味与苦味明显相关，可通过该计算方法来预测甜菊糖苷的风味。此外，味觉受体的空间位阻是导致甜菊糖苷C-13和C-19位上的葡萄糖基数量改变对其风味造成不同影响的主要原因。预测了数种改性甜菊糖苷的风味并挑选出可能的优质甜味剂。

Abstract:

This study investigated the interaction between a series of steviol glycosides(SG) and human taste receptors with computational simulation. Firstly，the homology models of human sweet taste receptors hT1R2/hT1R3 and bitter taste receptor hT2R4 were built. Ramachandran plot and several quality factors were used to check the model quality. Then molecule docking studies between taste receptors and a group of natural SG were performed. The interaction energy and patterns of the docking procession were analyzed. It was found that the docking results of SG were obviously correlated with their sweetness and bitterness. So the probable flavor of other SG could be predicted by the computational approach. In addition，the sweetness and bitterness of SG showed different trends with the change in amount of glucose residues at the C-13 and C-19 positions，which appeared to be caused by the unique structure of the taste receptors. Finally，the study predicted the flavor of several modified SG and subsequently suggested possible potent sweeteners.