RESUMEN
Using the qualified rates of particles as the evaluation indexes, the impact tactors of one-step pelletization technology of Jiuwei Xifeng granules were selected from six factors by the Plackett-Burman experimental design and the levels of non-significant factors were identified. According to the Plackett-Burman experimental design, choosing the qualified rates of particles and angle of repose as the evaluation indexes, three levels of the three factors were selected by Box-Behnken of central composite design to optimize the experimental. The best conditions were as follows: the fluid extract was sprayed with frequency of 29 r . min-1, inlet air temperature was 90 °C, the frequency of fan was 34 Hz. Under the response surface methodology optimized scheme, the average experimental results are similar to the predicted values, and surface methodology could be used in the optimization of one-step pelletization for Chinese materia medica.