3种巯基蛋白酶对去磷酸化牛乳β-酪蛋白和茶黄素复合膜的清除

Effectiveness of Three Kinds of Cysteine Proteases on Dephosphorylated Bovine β-casein/theaflavin Complex Film Removal.

目的:采用茶黄素(theaflavin,TF)和去磷酸化牛β-酪蛋白(dephosphorylated bovineβ-casein,Dβ-CN)在芯片表面形成蛋白质/色素复合膜的模型,评估3种巯基蛋白酶(cysteine proteases,CPs),木瓜蛋白酶、菠萝蛋白酶和无花果蛋白酶,对Dβ-CN/TF复合膜的清除作用。方法:在消散石英晶体微天平(quartz crystal microbalance with dissipation,QCM-D)上建立Dβ-CN/TF复合膜,Boltzman方程评估3种CPs水解复合膜的效率,水解前后膜变化通过原子力显微镜(atomic force microscopy,AFM)和接触角表征。结果:3种CPs水解复合膜的效率由大到小依次为无花果蛋白酶、木瓜蛋白酶、菠萝蛋白酶(P<0.05)。AFM图和接触角表征结果证实,CPs能够有效地清除结合在Dβ-CN表面的TF。结论:CPs具有在牙色渍清除中潜在的应用价值。在开发口腔保健产品中该类酶值得进一步研究。

Objective： To employ a model of protein/pigment complex film using theaflavin （TF） and dephospho- rylated bovine 13--casein （D^--CN） on a sensor surface to assess the efficacy of three kinds of cysteine proteases （CPs） including papain, stem bromelain, and ficin on removing Dβ--CN/TF. Methods： Di3--CN/TF complex film was built by using a quartz crystal microbalance with dissipation （QCM D）. The efficacies of CPs were assessed by Boltzman equation. The surface details before and after hydrolysis were detected by atomic force microscopy images and contact angles. Results： The efficacy order of CPs on hydrolyzing protein/pigment complex film was ficin ~ pa- pain ~ bromelain （P^0.05）. The results from atomic force microscopy images, and contact angles demonstrated that TF bound on the D^--CN was effectively removed by the CPs. Conclusion： This study indicates the potential application of the CPs for tooth stain removal and suggests that these enzymes are worthy of further investigation for use in oral healthcare.