荠菜总黄酮质量分数测定及超声提取工艺优化

采用UV法测定总黄酮的质量分数，通过超声辅助法进行提取，以铝盐显色法测定样品吸光度，以芦丁为标准溶液计算荠菜中总黄酮的质量分数.在单因素试验基础上，对影响因素提取温度、乙醇体积分数、超声提取时间、液料比进行正交试验，确定其最佳工艺条件.结果表明，不同来源荠菜中总黄酮质量分数为0.49%~3.83%.其中不同部位总黄酮质量分数花果中最高，其次是叶和茎；栽培品种较野生品种总黄酮质量分数高，变异小.荠菜总黄酮的最佳提取工艺条件是，提取温度65 ℃，乙醇体积分数50%，超声时间40 min，液料比（mL∶g）25∶1.该条件下荠菜总黄酮提取率达到89.26%.

Content Determination and Ultrasonic Extraction Techniques of Total Flavonoids fromCapsellae Bursa-Pastoris(L.)

UV spectrophotometry for determination of total flavonoids was used.Via ultrasonic extraction technique,using NaNO3-Al(NO3) to detect the absorbance of samples and taking lutin as comparison,the contents of total flavonoids were determined.On the basis of single factor experiments,the orthogonal experiment was used in the optimization of technological parameters:extracting temperature,ethanol concentration,extracting time,the ratio of solvent to raw materials.The result showed that the contents of total flavonoids in different kinds of Capsella bursa-pastoris L. were from 0.49% to 3.83%.The contents of total flavonoids in flowers & fruits were the highest，and then in leaves and stems.The contents of total flavonoids in cultivated varireties were higher than those in wile varireties.The optimum extraction conditions were as follows：temperature at 65 ℃,50% ethanol concentration,ultrasonic extraction for 40 min,and the 25∶1 ratio of solvent to raw materials.In these conditions,the total flavonoids extraction rate was 89.26%.