This article uses in the supercritical CO2 extract Asiatic plantain the ursolic acid. The supercritical CO2 extract take CO2 as the supercritical fluid (SpercriticalFluid,SCF）Because the SCF physical property like density, the viscosity, the diffusivity all enter along with it are situated between this material between the liquid and the gas. Supercritical fluid diffusion coefficient compared to its liquid state when senior general near 100 times, the viscosity and the gas are similar, when is lower than its liquid state greatly the viscosity, this causes the supercritical fluid to be able to look like the gas equally to have the characteristic which but the traversing very thin pipeline flows high speed. Therefore SCF has at the same time the liquid and the gas double gradings, the diffusion coefficient is big, the viscosity is small, the permeability is good. The supercritical CO2 solvation ability and the liquid are very close, have the superior mass transfer performance and dissolving capacity, compares with the traditional liquid solvent, is a more ideal solvent. The experiment proved the supercritical CO2 extract craft the application is enhances the product rate and the quality effective way. Or joins through the control pressure and the temperature change leads by the hand methods and so on medicinal preparation to be possible to cause the supercritical fluid solvation ability to change in the very wide scope, achieves the extract ursolic acid in some scope the goal. Uses the orthogonal cut-and-try method research Asiatic plantain for this this article to plant the ursolic acid the extraction craft.
