Extract the active ingredients of herbal medicine
The extraction, separation, and purification of active ingredients in herbal medicines have always been an important part and difficulty in herbal research. Because of the low content of active ingredients in herbal medicines; active ingredients and inactive ingredients coexist; similar structural components interfere with many, traditional extraction and separation methods Often the extraction rate is low, it is difficult to separate, and even cause pollution.
Supercritical CO2 fluid extraction
Supercritical CO2 fluid extraction technology is a high-tech material separation and purification technology with two processes of distillation and extraction that has emerged in recent years.
Supercritical CO2 fluid extraction has the characteristics of convenient operation, low energy consumption, no pollution, high separation capacity, and no solvent residues. It is widely used in medicine, food, environmental protection and other fields.
Extracting biologically active ingredients from natural animals, plants, and minerals for human health is an important part of pharmaceutical research. Most traditional extraction methods are inefficient. The application of supercritical CO2 fluid extraction is a revolution in natural medicine research.
However, CO2 is a non-polar substance with selective dissolution. Supercritical CO2 fluids are excellent for low-molecular-weight, low-polarity, lipophilic, and low-boiling components such as volatile oil, gluten, ester, lactone, distillate, epoxy compounds, etc. The solubility.
The active ingredients of most herbal medicines are compounds with more polar groups and larger molecular weights. Supercritical CO2 fluids are relatively difficult to extract large molecules and substances with more polar groups, and co-solvents need to be added to change their solubility.
The addition of co-solvent improves the selectivity and application range of the extracted components, and also improves the extraction efficiency. It is more and more widely used in herbal research. Supercritical CO2 extraction can also pre-treat herbal medicines to remove toxic or interfering components. .
Commonly used co-solvents include methanol, ethanol, acetone, ethyl acetate and so on.
The use of co-solvents in the extraction of natural active substances is just the beginning, and it needs to be widely promoted and used.
Choice of cosolvent
The choice of co-solvent must first be based on the experimental results. In the initial selection, it is necessary to understand the physical and chemical properties of the extracted substance, such as molecular structure, molecular polarity, molecular mass, and molecular volume. Choose a co-solvent that has good solubility for the extracted substance, can form an interaction force, and even can form a hydrogen bond to improve the extraction efficiency and selectivity.