南极磷虾蛋白体外消化产物特性及其成骨活性分析

Characterization and Proosteogenic Effect of in Vitro Digestion Products of Antarctic Krill Protein

本研究以南极磷虾蛋白为研究对象,探究其在模拟胃肠消化过程中蛋白质水解度、肽得率、消化率和水解氨基酸含量的变化,并在此基础上,评价最佳消化时间下不同质量浓度消化产物上清液的体外成骨活性。结果表明,南极磷虾蛋白经模拟胃肠消化后,上清液中蛋白质水解度、肽得率、消化率、水解氨基酸含量显著上升,并在肠液消化120 min时达到平衡,此时水解度为42.67%、肽得率为35.30%、消化率为82.21%。利用小鼠MC3T3-E1成骨细胞模型对不同消化时间点的南极磷虾蛋白消化产物上清液进行体外成骨活性评价,发现不同时间点的南极磷虾蛋白消化产物上清液均具有一定的促成骨细胞增殖活性,且肠液消化120 min产物促成骨细胞增殖活性最好。同时,通过活/死细胞染色、碱性磷酸酶活性和茜素红染色实验验证了南极磷虾蛋白肠液120 min消化产物上清液具有良好的细胞相容性,并通过增强碱性磷酸酶活性和细胞内钙元素的沉积促进成骨细胞分化与矿化,从而调节成骨细胞成骨活性。本研究结果可为南极磷虾蛋白的高值化应用提供理论依据。

This study examined changes in the degree of hydrolysis,peptide yield,digestibility,and hydrolyzed amino acid content during the simulated gastrointestinal digestion of Antarctic krill protein.Furthermore,the in vitro proosteogenic activity of different concentrations of the lyophilized residue from the supernatant of the digestion product at the optimal digestion time was evaluated.The results showed that the hydrolysis degree,peptide yield,digestibility,and hydrolyzed amino acid content in the supernatant from Antarctic krill protein digestion increased significantly with digestion time,reaching an equilibrium after 120 min of intestinal digestion,with a hydrolysis degree of 42.67%,a peptide yield of 35.30%and a digestibility of 82.21%.The supernatants at all digestion time points enhanced the osteogenic activity of mouse MC3T3-E1 osteoblasts,the one obtained after 120 min of intestinal digestion being the most effective.Living/dead cell staining,alkaline phosphatase(ALP)activity assay and alizarin red staining confirmed that the supernatant from intestinal digestion for 120 min had good cellular compatibility,promoted osteoblast differentiation and mineralization and consequently regulated its osteogenic activity by enhancing ALP activity and intracellular calcium deposition.The results of this study provide a theoretical basis for the high-value application of Antarctic krill protein.