Optimization of microwave-assisted extraction of phenolic compounds from Inula britannica L. using the Box-Behnken design

A closed-vessel microwave-assisted extraction (MAE) of phenolic compounds from the aerial parts of Inula britannica L. using single-factor experiments and the Box-Behnken design with four independent variables (liquid-to-solid ratio, ethanol concentration, extraction time, and temperature) was investigated. The ANOVA results showed that the obtained model was significant at a 95 % confidence level. The extraction parameters for the maximal total phenolic content (46.19 mg GAE/g DM) were determined to be 15.13 ml/g liquid-to-solid ratio, 55.95 % EtOH, 73.74 ℃C, and 5.73 min. Compared with classical maceration, the proposed MAE of phenolic compounds from I. britannica saves a lot of time and gives a high extraction yield. (author)