Traditional Chinese Medicine (TCM) Extracts

Solvent extraction of TCM extracts is a method based on the solubility of various components in herbal medicines in specific solvents. By selecting solvents that have high solubility for the active ingredients and low solubility for unwanted components, the effective constituents are dissolved and separated from the herbal matrix.

When a solvent is added to the raw herbal material (which should be appropriately ground), it gradually penetrates the cell walls through diffusion and infiltration, entering the cells and dissolving the soluble substances. This creates a concentration gradient between the inside and outside of the cells. As a result, the concentrated solution inside the cells continuously diffuses outward, while fresh solvent continues to enter the cells. This process is repeated until a dynamic equilibrium is reached between the intracellular and extracellular solutions. The saturated solution is then filtered off, and fresh solvent is added multiple times to ensure complete or near‑complete extraction of the desired components.

The preparation of TCM extracts typically involves various solvents and extraction methods to maximize the recovery of active ingredients. The commonly used solvents and extraction methods include the following:

Common Solvents:

1.Water

2.Ethanol

3.Methanol

4.Acetone

5.Ethyl Acetate

Common Extraction Methods:

1.Water Extraction

2.Alcohol Extraction

3.Ultrasonic‑Assisted Extraction

4.Cold Maceration

5.Reflux Extraction

6.Supercritical Fluid Extraction

7.Percolation