Evaluation of adsorbents for separation and purification of paclitaxel from plant cell cultures

In this study, we evaluated the efficiency of different adsorbents for the removal of plant-derived impurities during the pre-purification of paclitaxel from plant cell cultures. Using the synthetic adsorbents sylopute and active clay and their major components SiO2 and MgO, we performed adsorbent treatment and analyzed the paclitaxel precipitates recovered from hexane precipitation. When SiO2 was used, the highest purity (∼58.1%) and yield (∼91.5%) of paclitaxel were obtained. We also determined differences in the effectiveness of the adsorbent treatment according to changes in the surface area, pore volume and pore diameter of SiO2. Adsorbent treatment was more effective when pore diameter was larger (silica I [2.19 nm] < silica II [4.92 nm] < silica III [9.07 nm]). The highest purity (∼74.3%) and yield (∼92.9%) of paclitaxel were obtained when silica III was used in the adsorbent treatment. Pore diameter had a greater effect on the removal of plant-derived impurities during the pre-purification of paclitaxel compared with surface area and pore volume. This result could be confirmed by HPLC analysis of the absorbent after treatment and TGA of the organic substances that were bonded to the adsorbent.

► Various adsorbents are evaluated for purifying paclitaxel.
► SiO2 give the highest paclitaxel yield and purity.
► Pore diameter had a great effect on the removal of impurities.
► Adsorbent treatment can dramatically reduce the cost of separation/purification.