Unique phenolic constituent in Cimicifuga dahurica (Turcz.) Maxim. through Box-Behnken design and response surface methodology.

Cimicifuga dahurica (Turcz.) Maxim. exerts significant antioxidative due to its high phenolic constituent content. In this study, the extraction condition of the phenolic constituents and antioxidant effect was optimized by the Box-Behnken design and response surface methodology. Eleven main bioactive analytes of Cimicifuga dahurica (Turcz.) Maxim. were simultaneously quantified by high-performance capillary electrophoresis with diode-array detector to assess the effect of extraction technology. The optimal extraction parameters were determined as: the concentration of ethanol 56.21%, liquid/solid ratio 14.65:1, and extraction time 1.64 h for 2.67 times. According to the results, a maximal value of total phenolic acids (3.67 mg/g) was obtained. Meanwhile, the influence of different extraction technology on antioxidant activities were evaluated by 1,1-diphenyl-2-picrylhydrazyl, 2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulfonate), ferric reducing antioxidant power and hydroxyl radical scavenging method. The results presented here showed that the content of phenolic acid and antioxidant effect was much higher than the European Pharmacopoeia. Altogether, this method successfully applied response surface methodology to optimize the Cimicifuga dahurica (Turcz.) Maxim. extract with high antioxidant activities.