中药提取过程的动力学

KINETIC MODEL FOR EXTRACTION PROCESS OF CHINESE TRADITIONAL MEDICINE

目的 为中药提取工艺设计提供理论依据。方法 基于Fick扩散第二定律 ,建立中药提取过程的动力学方程 ,并以实验对其进行检验。结果 中药提取过程的动力学服从一级动力学方程 ,甘草、五味子、麦冬中有效成分以及丹参中丹参酮的提取等实验结果与动力学方程能较好地吻合 ,乙醇提取丹参酮的过程为内扩散控制的 ,其提取表观活化能为 2 0 2 6kJ·mol- 1 。结论 建立的中药提取过程的动力学方程是可靠的。

AIM To present a theory bases for Chinese traditional medicine extraction process. METHODS A kinetic equation for Chinese traditional medicine extraction process was presented based on Fick's second law of diffusion. Experiments for extracting tanshinone from Salvia miltiorrhiza Bge with ethanol under different particle sizes and temperatures were studied. In addition, the data of extraction process of three kinds of herbs, including Glycyrrhiza uralensis Fisch, Schisandra chinesis and Ophiopogon japonicus (Thunb.) Ker-Gawl were introduced to evaluate the kinetic equation. RESULTS The kinetic of Chinese traditional medicine extraction process agreed with the first-order rate equation. Experiment data of active components extracted from the herbs above could perfectly match with the kinetic equation. The rate-determining step for extracting tanshinone from Salvia miltiorrhiza Bge was the diffusion of tanshinone through the herb particles. The apparent activation energy for tanshinone diffusion process was 20.26 kJ·mol -1 . CONCLUSION The relation between the concentration of active component and extraction time, size of herb particles and temperature could be got from this kinetic equation. The extraction process of other herbs besides the above could be described by this equation.