Optimization of microwave-assisted extraction of triterpenoids from Gynura procumbens by response surface methodology

To optimize technological parameters for mircrowave-assisted extraction yield of total triterpenoids from Gynura procumbens. The experiments investigated the effects of extraction,such as ethanol concentration,extraction time,microwave power,temperature,and ratio of solid to liquid. Further,the experiments were optimized using a Box-Behnken method of test design and response surface methodology on the basis of the single factor experiment. When the ethanol concentration was 90% and microwave power was 600 W,the optimal extraction conditions were as follows:extraction time was 8.6 min,temperature was 57.7 ℃ and ratio of solid to liquid was 1∶33 g/m L. Under these conditions,the extraction yield of total triterpenoids from Gynura procumbens was up to 2.13%,which was well matched with predicted yield 2.14%.