Department of Food Biochemistry and Analysis, Poznan University of Life Sciences, Wojska Polskiego 28, 60-637 Poznan, Poland.
Food Chem. 2014 Jan 15;143:418-26. doi: 10.1016/j.foodchem.2013.08.015. Epub 2013 Aug 11.
This study describes in vitro digestion of lupin seed globulins by pancreatin, trypsin and chymotrypsin. Lupin seed globulins turned out to be almost totally susceptible to chymotrypsin digestion. When panceratin or trypsin were used for digestion of lupin seed globulins, γ-conglutin appeared to be resistant to proteolysis. Different fluorescence spectroscopic methods such as fluorescence anisotropy, fluorescence lifetimes and fluorescence quenching measurements were used for detailed characterisation of this phenomenon. A potential reason for γ-conglutin insensitivity to digestion may be related to the fact that lysine, as well as arginine, are positively charged at cell physiological pH. Simultaneously, flavonoids at this pH are partially ionised, which may lead to the occurrence of ionic interactions between these molecules at pH 7.5. The confirmation of this explanation may be the fact that γ-conglutin and vitexin form a static complex, which was observed using fluorescence quenching measurements.
本研究描述了胰蛋白酶、胰蛋白酶和糜蛋白酶对羽扇豆球蛋白的体外消化。羽扇豆球蛋白几乎完全易受糜蛋白酶消化。当使用胰蛋白酶或胰蛋白酶消化羽扇豆球蛋白时，γ-伴大豆球蛋白似乎对蛋白水解具有抗性。荧光各向异性、荧光寿命和荧光猝灭测量等不同荧光光谱方法用于详细表征这一现象。γ-伴大豆球蛋白对消化不敏感的一个潜在原因可能与赖氨酸以及精氨酸在细胞生理 pH 值下带正电荷有关。同时，黄酮类化合物在该 pH 值下部分离子化，这可能导致这些分子在 pH 值为 7.5 时发生离子相互作用。对这一解释的确认可能是 γ-伴大豆球蛋白和牡荆素形成了一个静态复合物，这一点可以通过荧光猝灭测量观察到。
