荷叶多酚提取优化及其清除DPPH·自由基的研究

优化荷叶多酚提取工艺提高荷叶资源利用。在单因素实验的基础上,采用响应面分析法对提取时间、液料比、提取温度和pH等提取条件进行了优化。结果表明,45%乙醇溶剂提取荷叶多酚较好;曲面回归方程拟合性好;优化工艺为:乙醇浓度45%,提取时间35·3min,液料比64·6mL/g、提取温度52·3℃、pH4·7,荷叶多酚得率为19·83mg/g·干粉。荷叶多酚提取物清除DPPH·的IC50为125μg/mL。 

Optimization of extraction process of polyphenols from lotus leaf and its DPPH radical scavenging activity

Optimization of extraction conditions for the polyphenols yield from Lotus Leaf can make full use its polyphenols resource. Based on single-factor experiment results, effects of extraction time, ratio of solvent to material,extraction temperature and solvent pH on polyphenols yield were analyzed with response surface method (RSM).The results showed that the optimum conditions of polyphenols extraction were:ethanol concentration of 45%, extraction time of 35.3min, extraction temperature of 52.3℃, ratio of solvent to material of 64.6mL/g ·dry basic and that the polyphenols yield was up to 19.83mg/g· dry basic, and these predicted values were also verified by validation experiments.The extract exhibited scavenging potential with IC_(50) value of 125μg/mL for DPPH.