China's vast, complex geographical environment and the changing climate conditions make the species diversity in China, especially those with special oil, flavors and fragrances of the medical and health effects of pigment, is rich in natural resources.

Though it is an ideal way of using CO2 supercritical fluid extraction to get the active substances in the natural products because of its heat-sensitive, only under the ultrahigh pressure can run. Extremely high pressure limits to enlarge the effective volume of the device. At the same time, higher equipment manufacturing and running costs restrict the technique and its application in the production of effective components of natural products.

Sub-critical extraction of lipid-soluble substances patent technology is the "Torch plan" of the State Science and Technology Commission, is the "Pilot project on science and technology" of the State Development Planning Commission, and also the "Science and technology demonstration program" of the state economic and trade commission. It is widely applied in special cooking oil, plant protein, fine chemical, natural pigment, medicine and food industries, successively built more than 40 engineering projects in domestic.