Abstract：
Ketogenic diet, characterized by high fat and low carbohydrate content, is gradually becoming a new perspective in the human diet; however, the mechanism of digestion of ketogenic diet remains unknown. In this study, we explored the oil-water interface to elucidate the digestion of a ketogenic diet based on typical representative medium- and long-chain triglycerides. The free fatty acids (FFAs) release indicated that glycerol trioctanoate with a shorter carbon chain (FFA = 920.55 ± 10.17 μmol) was significantly more digestible than glycerol tripalmitate (851.36 ± 9.48 μmol) and glycerol tristearate (805.81 ± 10.03 μmol). Particle size analysis revealed that the length of the carbon chain increased the size of triglycerides, resulting in a decreased contact area with lipase. The interfacial phenomenon indicated that the longer the carbon chain of triglycerides, the greater the reduction in binding capacity with salt ions in the digestive solution. Fluorescence spectroscopy analysis showed that the length of the carbon chain induced the displacement of the lipase peak, suggesting that the carbon chain length could alter the structure of lipase. Molecular dynamics simulation showed that the longer the carbon chain of triglycerides, the easier it was to loosen the structure of lipase. Bond energy analysis showed that the carbon chain length of triglycerides was positively correlated with the bond energy strength of the ester bonding. In conclusion, this study emphasizes that the ketogenic diet should primarily consist of shorter carbon chain triglycerides because carbon chain length can alter the digestion of triglycerides. This provides a new perspective on the quest for more effective ketogenic diet, in line with the current view of healthy diet.
摘要：
生酮饮食，以高脂肪和低碳水化合物含量为特征，正逐渐成为人类饮食的新视角；然而，生酮饮食的消化机制仍然未知。在这项研究中,我们探索了油-水界面，以阐明基于典型代表性的中链和长链甘油三酯的生酮饮食的消化。游离脂肪酸（FFA）的释放表明，碳链较短的三辛酸甘油酯（FFA=920.55±10.17μmol）比甘油三棕榈酸酯（851.36±9.48μmol）和甘油三硬脂酸酯（805.81±10.03μmol）明显更易消化。粒度分析表明，碳链的长度增加了甘油三酯的大小，导致与脂肪酶的接触面积减少。界面现象表明，甘油三酯的碳链越长，消化液中与盐离子的结合能力降低越大。荧光光谱分析表明，碳链的长度诱导了脂肪酶峰的置换，表明碳链长度可以改变脂肪酶的结构。分子动力学模拟表明,甘油三酯的碳链越长,更容易松开脂肪酶的结构。键能分析表明，甘油三酯的碳链长度与酯键的键能强度呈正相关。总之,这项研究强调生酮饮食应主要由较短的碳链甘油三酯组成，因为碳链长度可以改变甘油三酯的消化。这为寻求更有效的生酮饮食提供了新的视角，符合当前健康饮食的观点。
