Maya Luis E, Scanlon Martin G
Department of Food and Human Nutritional Sciences, University of Manitoba, Winnipeg, MB, R3T 2N2, Canada.
Curr Res Food Sci. 2020 Nov 25;3:296-303. doi: 10.1016/j.crfs.2020.11.003. eCollection 2020 Nov.
The thermodynamic properties of bioactive peptides provide insights into their functional behavior and their biological efficacy. We conducted precise analyses of the density, the ultrasonic velocity and the relative attenuation of serial dilutions of three commercial dairy peptides prepared by enzymatic methods. From these we determined the partial specific volume and the partial specific adiabatic compressibility coefficient for the peptides. At concentrations greater than ~2.5 mg mL, the apparent values for specific volume and adiabatic compressibility were constant, differing between the three peptides at ±3% for specific volume and ±70% for compressibility. Both specific volume and adiabatic compressibility were highly dependent on concentration, indicating the importance of precise low concentration measurements to obtain correct values for these thermodynamic parameters. From these parameters it was apparent that restructuring of water molecules around the peptides (and their associated counterions) led to compact solutes that were also incompressible. These thermodynamic analyses are critical for understanding how the properties and the beneficial effects of bioactive peptides are influenced by their chemical environment.
生物活性肽的热力学性质有助于深入了解其功能行为和生物学功效。我们对通过酶法制备的三种商业乳源肽的系列稀释液的密度、超声速度和相对衰减进行了精确分析。由此我们确定了肽的偏比容和偏比绝热压缩系数。在浓度大于约2.5 mg/mL时，比容和绝热压缩率的表观值是恒定的，三种肽之间的差异为：比容±3%，压缩率±70%。比容和绝热压缩率都高度依赖于浓度，这表明精确测量低浓度对于获得这些热力学参数的正确值很重要。从这些参数可以明显看出，肽（及其相关抗衡离子）周围水分子的重组导致了致密且不可压缩的溶质。这些热力学分析对于理解生物活性肽的性质和有益效果如何受到其化学环境的影响至关重要。
