蒲公英中黄酮的响应面法优化提取和同步荧光法检测研究

Optimal Extraction of Flavonoid from Dandelion via Response Surface Method and Its Synchronous Fluorescence Method Detection

本试验应用响应面法优化超声-微波协同萃取蒲公英中黄酮的提取工艺,并建立测定黄酮含量的同步荧光法。在单因素试验结果的基础上,以提取溶剂乙醇浓度、微波功率、萃取时间和料液比为自变量,提取液的荧光强度为响应值,设计4因素3水平响应面试验,优化蒲公英中黄酮的提取工艺;单因素试验确定同步荧光法的测定条件。结果表明:1)判定系数R^(2)=0.9648,说明模型与实际结果拟合程度好,所得模型能解释96.48%的响应值改变,校正判定系数(R_(Adj)^(2)=0.9295)与预测判定系数(R_(Pred)^(2)=0.8860)接近。2)响应面法优化超声-微波协同萃取技术提取蒲公英中的黄酮,其最佳提取条件为乙醇浓度50%,微波功率250 W,萃取时间30 min,料液比1∶30(g∶mL)。3)同步荧光法的最佳测定条件为波长差值(Δλ)=55 nm,Al(NO_(3))_(3)浓度0.2%,加入pH=6的醋酸-醋酸钠缓冲液1 mL,室温条件下反应50 min。在最佳测定条件下,测得蒲公英中黄酮的含量为3.52 mg/g。由此可见,响应面法优化提取工艺能较好地用于蒲公英中黄酮的提取,同步荧光法测定黄酮含量的方法干扰少、准确度高。

This experiment was conducted to optimize the ultrasonic-microwave synergistic extraction process of flavonoids from the dandelion by the response surface method.Furthermore,a synchronous fluorescence method was established for the detection of the flavonoid content.The extraction process was optimized by response surface test of four factors and three levels based on the single factor test results.In this process,ethanol concentration,microwave power,extraction time and solid-liquid ratio were used as the independent variables,while the fluorescent intensity of extraction solution was served as the response value.The measurement conditions of synchronous fluorescence method were determined by conducting a single factor experiment.The results were summarized as follows:1)the determination coefficient R^(2)=0.9648 indicated that the model fitted well with the actual results,and the obtained model could explain the 96.48%change of the response value.The predicted determination coefficient(R_(Pred)^(2)=0.8860)was reasonable consistent with the adjusted determination coefficient(R_(Adj)^(2)=0.9295).2)The optimum extraction conditions for ethanol concentration,microwave power,extraction time and solid-liquid ratio were identified as 50%ethanol,250 W,30 min,and 1∶30(g∶mL),respectively.3)The optimum detection conditions of synchronous fluorescence method were set as that the wavelength difference value(Δλ)was 55 nm,the concentration of Al(NO_(3))_(3)was 0.2%,acetate-sodium acetate buffer solution(pH=6)was 1 mL,and reaction time was 50 min at room temperature.Under the optimum detection conditions,the content of flavonoid in dandelion was 3.52 mg/g.Therefore,the extraction process optimized by the response surface method can be used to extract the flavonoids in dandelion.Moreover,the synchronous fluorescence method possesses the advantages of low interference and high accuracy in terms of flavonoids determination.[Chinese Journal of Animal Nutrition,2023,35(2):1349-1360]