Optimization of shikonin homogenate extraction from Arnebia euchroma using response surface methodology

An efficient homogenate extraction technique was employed for extracting shikonin from Arnebia euchroma. The homogenate extraction procedure was optimized and compared with other conventional extraction techniques. The proposed method gave the best result with the highest extraction efficiency in the shortest extraction time. Based on single-factor experiments, a three-factor-three-level experimental design has been developed by Box-Behnken design. The optimal conditions were 78% ethanol as solvent, homogenate extraction time of 4.2 min, 10.3 liquid to solid ratio and two extraction cycles. Moreover, the proposed method was validated by stability, repeatability and recovery experiments. The developed homogenate extraction method provided a good alternative for the extraction of shikonin from A. euchroma. The results indicated that the proposed homogenate extraction was a convenient, rapid and efficient sample preparation technique and was environmental friendly. Furthermore, homogenate extraction has superiority in the extraction of thermally sensitive compounds from plant matrices.