Key Laboratory of Functional Dairy, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, P. R. China.
Mol Nutr Food Res. 2012 Oct;56(10):1511-9. doi: 10.1002/mnfr.201200085. Epub 2012 Aug 28.
In this study, we intend to clarify the role that milk proteins and fat may play in affecting the bioavailability and the antioxidant activity of jujube juice phenolics.
Three milk preparations-skimmed milk, milk fat, and whole milk were produced to represent milk protein, milk fat, and milk protein and fat together, respectively. The bioavailability of phenolics and the rat plasma antioxidant capacity were measured for 8 h after the consumption of jujube juice with and without milk preparations. The addition of skimmed milk to jujube juice resulted in significant changes in the plasma kinetics profile of phenolics, rather than affecting the overall absorption. Milk fat did not interact with jujube juice phenolics. However, when jujube juice was ingested with whole milk, a significant reduction of the bioavailability of phenolics and the maximum increase in plasma antioxidant capacity was observed. Moreover, a consistent increase in the median diameters of the emulsions indicated the formation of complexes of proteins, fat, and phenolics during digestion.
The present study suggests that when ingested with jujube juice, milk proteins and fat play different roles in affecting the bioavailability and the antioxidant activity of jujube juice phenolics.
本研究旨在阐明乳蛋白和乳脂在影响红枣汁酚类化合物生物利用度和抗氧化活性方面可能发挥的作用。
分别制备脱脂奶、乳脂和全脂奶三种奶品，以代表乳蛋白、乳脂和乳蛋白与乳脂的共同作用。在摄入含或不含奶品的红枣汁后 8 小时内，测定酚类化合物的生物利用度和大鼠血浆抗氧化能力。向红枣汁中添加脱脂奶会显著改变酚类化合物在血浆中的动力学特征，而不是影响整体吸收。乳脂与红枣汁中的酚类化合物没有相互作用。然而，当全脂奶与红枣汁一起摄入时，酚类化合物的生物利用度显著降低，血浆抗氧化能力的最大增加也观察到。此外，乳液的中值直径持续增加表明在消化过程中形成了蛋白质、脂肪和酚类化合物的复合物。
本研究表明，当与红枣汁一起摄入时，牛奶蛋白和脂肪在影响红枣汁酚类化合物的生物利用度和抗氧化活性方面发挥着不同的作用。
