ABSTRACT
Objective: To optimize the technology of freeze-dried powder of various fractions from lumbricus (Pheretima) by Box-Behnken design and response surface method. Methods: Using single factor experiment with Box-Behnken response surface method, freeze-dried rate as the index, the effects of sublimation temperature, sublimation time, analytical drying temperature, and drying time on the freeze-drying process were observed; The freeze-drying process of the active components in lumbricus was optimized; Using HPLC method, the fingerprint of the sample by the optimized technology was investigated, and the similarity of fingerprint was compared with the earthworm medicine, and the optimum freeze-drying process was obtained. Results: The best freeze-drying process conditions of active components in lumbricus were as follows: frozen temperature of -26.5 ℃, precool for 4 h, sublimation drying temperature of -20 ℃, sublimation time of 7 h, analytical drying temperature of 30 ℃, analytical drying time of 3.5 h, freeze-dried rate of 96.55%, and compared with medicinal materials of amino acid, the similarities of fingerprint were both greater than 0.9. Conclusion: Box-Behnken response surface method is used for the freeze-drying process conditions of active components in the lumbricus, the optimization is feasible, the effect of model is good, and this optimization process has the feasibility.