Negative pressure cavitation fractional precipitation for the purification of paclitaxel from Taxus chinensis

摘要

Abstract The precipitation efficiency of paclitaxel from Taxus chinensis was remarkably improved through negative pressure cavitation fractional precipitation. When paclitaxel was precipitated under a negative pressure of ?200 mmHg, almost all of the paclitaxel (<97) could be recovered in a short operation time (1 min). The precipitation rate constant was calculated using the JMAK equation for kinetic analysis. The rate constant in the case of negative pressure (?50 to ?200 mmHg) cavitation fractional precipitation increased by 2.147–6.046 times compared to fractional precipitation without negative pressure. The change of activation energy by the negative pressure (?50 to?200 mmHg) was also calculated using the Arrhenius equation. The activation energy changes were ?1,767 to ?4,161 J/mol, implying that the activation energy could be reduced by introducing negative pressure, resulting in an increased precipitation rate. In addition, the application of negative pressure reduced the size of the precipitate by 3.3 times and increased the diffusion coefficient of paclitaxel by 4.4 times.