响应面法优化茶多酚乙酰化工艺条件

Optimization of Acetylation Conditions of Tea Polyphenols Using Response Surface Methodology

本实验以茶多酚改性产物对DPPH自由基抑制率为参数,结合单因素实验,利用响应面分析法建立了茶多酚乙酰化多元二次回归方程模型,优化了茶多酚乙酰化工艺条件。结果表明,茶多酚乙酰化的最优工艺条件为:料液比为1∶8.31,催化剂吡啶用量为0.32 g,在61.5℃下回流反应2.03 h,所得改性茶多酚DPPH自由基抑制率为0.9318,与模型预测结果的相对误差-0.64%,为未改性茶多酚的7.64倍。此条件下产物透光率为0.926,与未改性产品相比,脂溶性提高了4.12倍。改性茶多酚的抗氧化能力优于丁基羟基茴香醚(BHA)与特丁基对苯二酚(TBHQ)这两种常见抗氧化剂。

In this study, multiple quadratic regression equation model for the optimization of acetylation conditions of tea polyphenol was established by response surface analysis. The condition of acetylating tea polyphenol was optimized using DPPH free radical scavenging rates as index. The optimized acetylating conditions were as foUows：liquid-to-solid ratio was 8.31 ,catalyst dosage was 0.32 g and reflux reaction under 61.5 ℃ for 2.03 h. The DPPH free radical scavenging rates of the synthesized compound achieved 0. 9318 ,with RSD of -0.64% compare with the predicted value. It was 7.64 times to that of the unmodified tea polyphenol. In addition, the light transmittance of the synthesized compound was 0. 926. The lip-solubility of the synthesized compound was 4.2 times more than that of unmodified tea polyphenol. The antioxidant activity of modified tea polyphenol was better than BHA and TBHQ.