甘薯叶绿原酸的微波协同双水相提取及其抗氧化活性

采用微波辅助乙醇-磷酸氢二钾双水相的方法对甘薯叶中绿原酸进行提取,探讨了双水相体系的磷酸氢二钾用量、乙醇体积分数、液料比、提取时间和微波功率等因素对绿原酸提取的影响,并采用正交实验法进行优化。并以对照物VC作比较,通过清除DPPH·的能力对甘薯叶绿原酸粗提液抗氧化活性进行评价。实验结果表明:以40%乙醇溶液、磷酸氢二钾质量浓度100 mg/mL组合的乙醇-磷酸氢二钾双水相萃取体系,微波提取时间75 s、液料比100∶1(V/m)、微波功率为320 W等条件下,绿原酸得率可达(3.72±0.036)%。甘薯叶绿原酸粗提液清除DPPH·的能力强于对照物VC。本实验优化甘薯叶绿原酸的提取工艺参数准确可靠、稳定、可行,所提取的甘薯叶绿原酸纯度高、抗氧化活性较好,为甘薯叶的进一步资源化开发利用提供了参考。

Extraction Technology and Antioxidant Ability of Chlorogenic Acids in Sweet Potato Leaves Through Aqueous Two-phase Method Cooperated with Microwave

The chlorogenic acid were extracted from sweet potato leaves by the method of microwave assisted ethamol-dipotassium hydrogen phosphate aqueous two-phase system. The effects of factors such as the amount of dipotassium hydrogen phosphatet, the alcohol amount, the ratio of solvent and material, the extraction time and the microwave power on extraction of chlorogenic acid were investigated.Extractions were optimized by the method of orthogonal experiment. Besides, compared with the positive control VC, the antioxidant activity was evaluated by scavenging DPPH·ability of sweet potato chlorogenic acid extract. The experimental results show that: under the optimized conditions such as volume fraction of ethanol was 40%,dipotassium hydrogen phosphate concentration was 100 mg·mL-1,the ratio of solvent and material was 100 ml·g-1 ,the microwave power was 320 W,the extraction time was 75 s,the extraction rate of chlorogenic acids was 3.72 ± 0.036%.The sweet potato leaves ability of scavenging DPPH·chlorogenic acid extract is stronger than the positive control VC. The optimal parameters for the extraction process of chlorogenic acid from sweet potato leaf is accurate, stable and feasible, sweet potato chlorogenic acid good antioxidant activity, provide the technical basis for the development of the further utilization of sweet potato leaves.