紫色小白菜有机酸的提取优化及UPLC定量分析

为建立一种紫色小白菜中精准的有机酸提取及定性定量分析方法。本研究在单因素试验的基础上,采用Box-Behnken的中心组合试验设计原理,设计响应面试验优化紫色小白菜有机酸的提取工艺。结果表明,紫色小白菜有机酸提取的最优工艺参数为:乙醇浓度73%,料液比1∶21,超声时间11 min,超声温度70℃。通过超高效液相色谱法(ultra performance liquid chromatography,UPLC)对紫色小白菜叶片和叶柄部位有机酸进行定性定量分析,检测出苹果酸、柠檬酸、丙二酸、琥珀酸和酒石酸,其中苹果酸含量最高,分别为15.968、5.019 mg/g;其次为柠檬酸,分别为9.293、1.385 mg/g。定性定量结果表明,紫色小白菜叶片及叶柄部位含有丰富有机酸类物质,叶片部位苹果酸、柠檬酸、丙二酸、酒石酸含量均高于叶柄部位,而琥珀酸含量较低。

Optimization of organic acids and UPLC analysis of purple cabbage

In this study,an accurate method for the extraction,qualitative and quantitative analysis of organic acids from purple cabbage was established.On the basis of single factor test,the interaction effects of four crucial parameters were studied by central composite(Box-Behnken) and response surface methodology(RSM).The results showed that the optimum process for organ acid extraction was 73% of ethanol concentration,1∶21 of solid to liquid,11 min and 70 ℃.The organic acids in leaves and petioles of purple cabbage were qualitatively and quantitatively analyzed by UPLC.Five organic acids were detected∶malic acid,citric acid,malonic acid,succinic acid and tartaric acid.Among five organic acids,malic acid content is the highest,15.968 and 5.019 mg/g,and citric acid is the second,9.293 and 1.385 mg/g.The qualitative and quantitative results showed that the leaves and petiole of purple cabbage contained abundant organic acids, and the contents of malic acid, citric acid, malonic acid and tartaric acid in the leaves were higher than those in the petiole, while the contents of succinic acid were lower.