Optimum extracting technology of flavonoids from radix pueraria

The multiple influence factors were investigated through the single factor for researching the extraction technology of flavonoids from radix pueraria.Four factors of quality fraction of ethanol,extraction time,liquid-solid ratio and extraction temperature were chosen to optimize with response surface methodology(RSM).A mathematical model was established and the analysis of variance was carried out.The result shows that the obtained model is significant and the optimum extraction conditions are as follows:63.9% of quality fraction of ethanol,138.0min of extraction time,11.3mL/g of liquid-solid ratio,72.9 ℃ of extraction temperature and one time extraction;when extracting the pH value of solution does not need to adjust;the recycle use of ethanol is feasible.Using the process conditions,the theoretical extraction yield of flavonoids is 1 842.6μg/g;the practical extraction yield is 1 821.3μg/g.