Abstract: Objectives: To find out the best type of macroporous resin and determine the optimal process conditions for separation and purification of total saponins from Rhizoma Polygonati Odorati. Methods: The best type of macroporous adsorption resin for total saponins was determined by static adsorption and desorption experiments. Based on one-factor-at-a-time experiments, a four-factor, three-level orthogonal array design was employed for the optimization of four process parameters for improved adsorption and desorption rates. Results: LSA-33 macroporous resin was found to be the best resin among 6 types of macroporous resin tested. The best purification conditions for total saponins were determined as follows: crude extract from Rhizoma Polygonati Odorati (pH 6－7) was adsorbed for 4 h and then desorbed with 95% ethanol at a solvent-to-solid ratio of 37.5:1 (mL/g) for 2 h. As a result, the content of total saponins in the crude extract was increased to 41.75% from 12.28%. Conclusion: LSA-33 macroporous resin is effective in purifying total saponins from Rhizoma Polygonati Odorati with the advantages of easy operation, high safety and low cost and thus will have high application value.

Key words: Rhizoma Polygonati Odorati, total saponins, macroporous resin, purification