Plant extract is botanical science and technology and the main raw material for botanical preparations. At present, there are many methods commonly used for extracting plant extracts. This article describes 5 different extraction methods.
1. Solvent Extraction Method
The solvent extraction method uses solvent to extract active ingredients from solid raw materials. It uses the principle of "similar polarity and compatibility", according to the difference in solubility of various components, selects the solvent with high solubility for the extracted components and low solubility for impurities, and dissolves the extracted components from plants according to the principle of "concentration difference" out of the way.
During the extraction process, the concentration of the solvent, the ratio of solid to liquid, the extraction temperature, and the extraction time will directly affect the extraction rate of the active ingredients. Experiments show that the solvent extraction method can save the extraction time.
2. Ultrasonic extraction method
The principle of ultrasonic extraction is mainly a physical process. Using ultrasonic cavitation to accelerate the leaching of plant active ingredients.
Advantages: The extraction time is short, the extraction method is simple, the extraction rate is high, the extraction temperature is low, and the destruction of the active ingredients by high temperature and high pressure is avoided.
Disadvantages: high container requirements, noise, equipment amplification and other issues.
3. Supercritical fluid extraction
The extraction and separation are carried out with supercritical fluids instead of conventional organic solvents. Commonly used in volatile components, fat-soluble substances, highly heat-sensitive substances and valuable medicinal materials.
Supercritical fluid extraction (SFE) is a relatively new extraction and separation technology. Its principle is to replace conventional organic solvents with supercritical fluids for extraction and separation. Commonly used in volatile components, fat-soluble substances, highly heat-sensitive substances and valuable medicinal materials.
The extraction method has the advantages of not easy inactivation of active components, high product quality, and simultaneous completion of the extraction and separation process.
Disadvantages: high-voltage equipment, large one-time investment, and high operating costs.
4. Microwave-assisted extraction
Microwave.assisted extraction (MAE) is a new technology that uses microwave energy to improve extraction efficiency. There are differences in the ability of substances to absorb microwaves in the microwave field, and some components can be selectively heated and extracted.
The extraction speed of this extraction method is much faster than the traditional method. Avoid destruction and degradation of valuable components while reducing extraction time. For liquid extraction systems, the solvent species is required to be polar. Non-polar solvents are not sensitive to the action of microwaves.
5. Enzyme extraction method
A method of using cellulase, pectinase, protease, etc. to destroy the cell wall of plants to promote the dissolution and separation of plant active ingredients to the greatest extent. In this extraction method, the choice of the enzyme, enzyme concentration, pH value, enzymatic hydrolysis temperature, and enzymatic hydrolysis time will affect the extraction rate of plant extracts.
Although many extraction methods exist, supercritical fluid extraction, microwave-assisted extraction, etc. are now widely used as new extraction techniques.