采用控温搅拌法制备直链淀粉-槲皮素复合物,评价其热稳定性.基于分子动力学模拟方法,研究直链淀粉与槲皮素之间的相互作用.结果表明:在单因素试验基础上,经响应面法优化得到最佳工艺参数为温度50 ℃、时间2.0 h、质量比(mg/mg)17∶1,该条件下获得槲皮素包合率为(90.8±1.4)％,与预测值91.34％较接近.在60 ℃下评价槲皮素的损失率,结果表明复合物在42 d后的损失率为83.3％,明显低于槲皮素标准品,能够有效延长槲皮素的保存时间.傅里叶红外光谱分析显示槲皮素—C=C、苯环官能团特征峰在经直链淀粉包合后减弱或消失,表明槲皮素可能进入直链淀粉空腔内.通过分子动力学模拟分析直链淀粉在加入槲皮素前后均方根偏差(Root mean square deviation,RMSD)、均方根波动(Root mean square fluctuation,RMSF)、回转半径(Radius of gyration,Rg)、氢键数、溶液可及表面积(Solvent accessible surface area,SASA)等指标随时间的变化,结果表明直链淀粉的包合作用能够增强槲皮素的稳定性.相比单一直链淀粉,复合物在模拟过程中的轨迹变化波动较小.
Preparation,Stability and Molecular Dynamics Simulation of Amylose Quercetin Complex
A temperature controlled stirring method was used to prepare linear starch quercetin complex and evaluate its thermal stability,and further study the interaction between linear starch and quercetin based on molecular dynamics simulation methods.The results showed that,on the basis of single factor analysis,the optimal process parameters optimized by response surface methodology were temperature 50 ℃,time 2.0 hours,and mass ratio(mg/mg)17∶1.Under these conditions,the quercetion inclusion rate was(90.8±1.4)％,which was close to the predicted value 91.34％.The loss rate of quercetin was evaluated at 60 ℃,and the results showed that the loss rate of the complex after 42 days was 83.3％,significantly lower than that of the quercetin standard,which can effectively prolong the storage time of quercetin.Fourier transform infrared spectroscopy analysis shows that the characteristic peak of-C=C,the benzene ring functional group of quercetin weakens or disappears after being encapsulated by linear starch,indicating that quercetin may enter the cavity of linear starch.Through molecular dynamics simulation analysis,the root mean square deviation(RMSD),root mean square fluctuation(RMSF),radius of gyration(Rg),hydrogen bond number,and soluble accessible surface area(SASA)of linear starch were analyzed before and after the addition of quercetin.The results indicated that the inclusion effect of amylose can enhance the stability of quercetin,compared with linear starch,the trajectory changes of the complex during the simulation process were relatively small.
万方数据
维普
