Solvent extraction is a common extraction method of traditional Chinese medicine in our factory. The key is to select the suitable solvent and extraction method. But in the process of extracting Chinese medicine, the crushing degree, extraction temperature, extraction time and equipment conditions also affect the extraction efficiency, which must be considered. The following are some elements summarized by Henan natural plant material factory, for reference only.

(1) due to the process of extraction, such as infiltration, dissolution and diffusion, the more fine the sample is crushed, the larger the surface area, the faster the leaching process, but the higher the grinding degree, the large surface area of the sample, the enhancement of the adsorption, and the velocity of the shadow filtration. In addition, the samples with more protein and polysaccharide are used for solvent extraction, and the crushing is too fine. These components dissolve too much, so that the viscosity of the extract increases and even becomes colloid, which affects the dissolution of other components. The crushing of raw materials is related to the extraction solvent and the location of plants. Generally speaking, coarse powder (20 mesh) or thin sheet can be used when water is extracted. When the organic solvent is used, the granularity can be slightly finer, so that it is better than 60 mesh. The roots and stems can be cut into thin slices or coarse flour. The whole grass, leaves, flowers and fruits should be over 20 - 40 mesh.

(2) generally speaking, the extraction temperature is low, the impurity is less, the efficiency is low, the heat is much more impurity and the efficiency is higher. Because of the increase of temperature, the speed of molecular movement is faster, the rate of penetration, dissolution and diffusion is faster, so the extraction effect is good. But the temperature should not be too high, it is easy to destroy some components, and the content of impurities is also increased, which brings difficulties to the separation and refining in the future. Generally, it is suitable for heating at about 60 C, and the maximum is not more than 100.

(3) the concentration difference solvent enters the cell, after the composition dissolves, because the concentration difference between the inside and outside cell, diffuses outward, when the inside and outside reaches a certain concentration, the diffusion stops, that is, the dynamic balance, the composition no longer leach, if the solvent is replaced, the new diffusion is started, the repeated arc can be extracted completely, so the reflux extraction method is the most. Well, the impregnation method is the most frequent

(4) the extraction time is extended with the extraction time, and the amount of extract is also increased, the opposite time is too long, the useless impurities are also soaked out. If heated by hot water, 0.5h to LH is the best, at most not more than 3h, refluxing with ethanol, 1 / u1-2h for each time, and other organic The solvent can extend a little time.