苜蓿异黄酮纯化工艺研究

Purification of isoflavonoids extracted from alfalfa

通过静态吸附、解吸实验及静态吸附动力学实验,确定了采用大孔吸附树脂HPH480对苜蓿异黄酮进行纯化。动态吸附实验结果表明,对于苜蓿异黄酮,较好的动态吸附条件为,上样液浓度0.6～1.2mg/mL,上样液pH为5,径高比为1∶20,预吸附4h,流速2mL/min,上样液温度40℃,采用80%乙醇60℃洗脱,流速为1.0mL/min,洗脱剂用量为4BV,在此条件下得到的苜蓿异黄酮纯度可在10%以上,较粗提物可提高3倍以上。采用树脂吸附法与溶剂萃取法联用对异黄酮进行精制以乙酸乙酯表现较好,可使紫花苜蓿异黄酮提取物纯度达到13.69%。

The macroporous absorption resin HPH480 was selected as exclusive separation resin of isoflavone extracted from alfalfa. The results showed： the appropriate dynamic adsorption conditions for purification of isoflavonoids extracted from alfalfa are 0.6-1.2mg/mL of sample concentration, pH 5, 1：20 of diameter to height ratio,4h of pre-absorption,2mL/min of flow rate,40℃ of loading temperature,70% ethanol of elution solvent,60℃ of elution temperature,1.0mL/min of elution rate and 4BV of the elution solvent volume. Under these conditions,the purity of isoflavone in alfalfa extracts could reach to 10% which was about 3 times of the crude extracts. Macroporous absorption resin method was combined with solvent extraction method to refine isoflavones, it was shown that acetic ether extraction had better performance. It increased the purity of isoflavonoids extracts up to 13.69%.