Lactoglobulin is an important component of milk protein, which has a high nutritional value. However, it is susceptible to high temperatures, leading to a decline in dairy product quality. In order to evaluate the effect of different temperatures on lactoglobulin, molecular dynamics simulation was used to simulate and analyze the structural changes of lactoglobulin treated at different temperatures (25, 45, 70, 100 and 120 ℃) for 100 ns. Results showed that lactoglobulin was stable at 25 and 45 ℃; when the temperature increased to 70 ℃, the root mean square deviation, the root mean square fluctuation, the radius of gyration and the hydrophobic area solvent accessible surface area of lactoglobulin were significantly increased. These values reached a maximum level of 0.65, 0.99, 1.65 nm and 45 nm2, respectively, at 120 ℃. At 120 ℃, the number of hydrogen bonds inside lactoglobulin was significantly reduced, and the distance of salt bridge Glu45-Lys70 and Glu89-Lys60 was increased by 8Å and 16Å, respectively. The above results indicate that lactoglobulin begins to denature at temperatures above 70°C and more denaturation occurs with the increasing temperatures. This study demonstrates the influence of five different temperatures on the structure of lactoglobulin at the atomic level. It obtains detailed information on its structural changes, which provides a theoretical reference for selecting a suitable temperature in the production process of dairy products.
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