外界多因素对茶黄素类单体稳定性的影响

Variable stability of theaflavins monomers under different conditions

为提高茶黄素类(TFs)单体的应用效果,确定最佳的应用条件,需要了解茶黄素类单体的稳定性。实验采用茶黄素类各单体的标准品在不同外界条件下,通过HPLC法测定吸收峰面积值(响应值mAU)来判断茶黄素类单体的稳定性。结果表明:茶黄素类单体水溶液在50℃以上加热30 min不稳定;在酸性环境中较稳定,而在碱性环境中具有不稳定性;在有Fe存在的环境下不稳定;在超声中总体稳定;在冰箱(4℃)放置时缓慢分解,其中茶黄素(TF)单体比较稳定。结论为茶黄素在水溶液中不稳定,温度、碱性、Fe会明显影响茶黄素的稳定性,超声对其稳定性基本不影响,冰箱中放置缓慢分解,不宜长期处于水溶液体系中。

Understanding the stability of theaflavin monomers under different conditions is important to the practical and effective application of these molecules. In this study, the stability of theaflavins in different conditions was assessed using HPLC absorption peak area(mAU). Theaflavins were stable in ultrasound and acidic solutions. In contrast, theaflavins were unstable at temperatures above 50 ℃,in alkaline solutions, and in the presence of iron ions(Fe). Theaflavins slowly decomposed under refrigerated conditions(4 ℃).