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Application of ultrasonic technology in extraction of traditional Chinese medicine components
Chinese herbal medicine contains complex components, both effective and ineffective. In order to improve the therapeutic effect of Chinese herbal medicine, it is necessary to extract its effective components. Extraction is directly related to the content of effective components in finished products and their internal quality, bed monitoring efficacy and economic benefits.
At present, the common methods for extracting the effective components of Chinese herbal medicines in actual production are impregnation (normal temperature impregnation, warm impregnation and decocting method), percolation, reflux and so on. The extraction time is long and the extraction rate is low. With the development of modern science and technology, ultrasonic technology has been widely used in the fields of industry, agriculture, medicine and health. Because this method has the advantages of simple equipment, convenient operation, short extraction time, high extraction rate, energy saving, medicinal materials saving and no need of heating, its application in the extraction of Chinese herbal medicines has been paid more and more attention. This paper summarizes the application of ultrasonic technology in the extraction of Chinese herbal medicine components and the problems that should be paid attention to in the extraction process.
Theoretical basis of 1 ultrasonic extraction of Chinese herbal medicine components
Ultrasonic wave is a kind of elastic mechanical vibration filter, which is a vibration that exceeds the hearing threshold. It produces strong vibration, high speed, strong cavitation effect and stirring effect, thus destroying the cells of plant medicinal materials and making the solvent penetrate into the cells of medicinal materials, thus accelerating the dissolution of effective components in the solvents and improving the extraction rate of effective components. At the same time, compared with the effective components extracted by conventional methods, whether the structure of effective components extracted by ultrasonic wave has changed is investigated. According to literature reports, the effective components obtained by the two methods were compared and analyzed by TLC, IR and NMR. The spectra obtained by the two methods were consistent, which indicated that ultrasonic extraction would not change the structure of effective components, shorten the extraction time and improve the extraction rate, and provided a new method for rapid and high-yield extraction of Chinese herbal medicine components.
Application of ultrasonic technology in the extraction of Chinese herbal medicine components
2. Extraction of1Saponins Saponins are usually extracted by soaking in decocting method or organic solvents, which takes a long time and has a low extraction rate. Ultrasonic technology can shorten the extraction time and improve the extraction rate. Song Xiaomei and others extracted gypenosides from Gynostemma longipedunculata. Compared with 75% ethanol reflux extraction, ultrasonic extraction for 80min for three times can obviously improve the yield of gypenosides. Shao et al. extracted codonopsis saponin from codonopsis pilosula. Compared with the conventional solvent soaking method, the extraction rate of codonopsis pilosula saponin was increased by 65438 0 times and the time was shortened by 98.6% after ultrasonic treatment for 40min. In addition, the crude product obtained by ultrasonic extraction is nearly twice as high as that obtained by conventional methods, and the purity is also high. Experts mentioned that diosgenin is a 30-minute effective component in the rhizome of Dioscorea nipponica Makino. Taking 70% ethanol soaking for 48h as the control, the extraction rate is 65,438 0.2 times and 65,438 0.34 times higher than that of the control. This technology can save 23.4% of medicinal materials. It can be seen that ultrasonic extraction of saponins has the advantages of saving time, medicine, less impurities and high extraction rate.
2.2 Extraction of Alkaloids Conventional extraction of alkaloids from Chinese herbal medicines generally takes a long time and the yield is low, but after ultrasonic treatment, better results can be obtained. Berberine was extracted from Phellodendron amurense, soaked in saturated lime water for 24 hours as a control, and extracted by 20kHz ultrasonic for 30 minutes. The extraction rate was increased by 65438 08.26% compared with the control, and the structure of berberine remained unchanged. Guo Xiaowu and others extracted berberine from Rhizoma Coptidis. The experiment proved that the ultrasonic method was superior to the soaking method, that is, the extraction rate was as high as 8. 12% after ultrasonic treatment for 30min at 20kHz. In China Pharmacopoeia (1985 edition), toxic components such as strychnine and brucine are extracted by ultrasonic technology, and it is clearly stipulated that when determining the drug content, ultrasonic treatment for 40min is equivalent to cold soaking for 24 hours. It can be seen that ultrasonic technology is simple, time-saving and has high extraction rate.
2.3 Flavonoids are usually extracted by adding water to decocting method, alkali extraction and acid precipitation, or soaking in ethanol and methanol, which is time-consuming and laborious, and the extraction rate is low, while ultrasonic extraction can improve the extraction rate and shorten the extraction time. Baicalin is the main effective component extracted from the rhizome of Scutellaria baicalensis Georgi. With water as solvent, the extraction rate of baicalin was higher than that of water decoction for 3 hours and ultrasonic extraction for 40min minutes at 20kHz, and the extraction rate of baicalin was the highest. Ultrasonic extraction of rutin from Sophora japonica for 40min. The extraction rate is 22.53%, which is 0.7 ~ 2 times of the current mass production rate of 65438. The comparative test shows that it saves 30~40% of medicinal materials and has high economic benefits.
2.4 Anthraquinone derivatives extracted from plants are complex in morphology. In the same Chinese herbal medicine, there are often free forms and combined forms. Generally, ethanol or dilute alkaline aqueous solution is used for extraction, which destroys the effective components and affects the extraction rate. Compared with the traditional strong cooking method, the extraction rate of anthraquinone from rhubarb by ultrasonic extraction for 65438±00min is higher than that by decocting for 3 hours. At the same time, the ultrasonic extraction method with frequency of 20kHz has the highest extraction rate. In the extraction process of Compound Shouwu Oral Liquid, Polygonum Multiflori Radix, Radix et Rhizoma Rhei and Senna Leaves containing a large amount of anthraquinone derivatives were extracted by ultrasonic wave, which prevented the anthraquinone glycosides from destroying the effective components due to long-term decoction.
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First, the principle of ultrasonic extraction of Chinese herbal medicine
Cavitation effect of ultrasonic wave.
The application of ultrasonic technology in extraction and homogenization is based on Huygens wave theory and the unique "cavitation effect" of ultrasonic wave propagation in liquid continuous medium.
Result.
The principle of (1) Huygens wave points out that when a wave (including the vibration of super source and wave source) propagates in a continuous medium, it will cause dielectric particles on its wave front.
Every point the wave source reaches in the medium will cause the vibration of adjacent particles and become a new wave source. The fluctuation caused by this wave source makes it on the propagation path.
Each particle will gain acceleration and kinetic energy. Ultrasonic wave can make the acceleration of medium particles reach more than 1000 times of gravity. Unde that action of ultrasonic waves,
Tens of thousands of high-frequency oscillations per second and huge speed and kinetic energy greater than 100m per second act on solution molecules, which quickly activate solution molecules.
(2) Ultrasonic wave has a unique "cavitation effect" in liquid medium, which constantly produces numerous microcavities with internal pressure of thousands of atmospheres and constantly "explodes".
Strong micro shock waves are generated, which act on solid-liquid or liquid-liquid molecules, so that the air in the medium is "bombarded" to escape, and the rupture and deformation of medium cells are accelerated.
The substance in the medium molecule escapes.
(3) Mechanical vibration, micro-jet and micro-acoustic flow caused by the physical characteristics of ultrasonic wave propagation in the medium all promote the expansion of effective components in the solution.
Spread out.
2. Advantages of ultrasonic extraction
(1) Ultrasonic extraction efficiency is high. Ultrasonic wave has unique extreme physical characteristics, which can promote the wall breaking or deformation of plant tissues and make the effective components of traditional Chinese medicine more fully extracted.
Compared with the traditional process, the extraction rate is significantly improved by 50-500%.
(2) The ultrasonic extraction time is short. Ultrasound-enhanced extraction of traditional Chinese medicine usually takes 24-40 minutes to obtain the best extraction rate, and its extraction time is longer than that of traditional technology.
The method is shortened by more than 2/3, and the processing capacity of medicinal materials is large.
(3) The ultrasonic extraction temperature is low. The optimum temperature for ultrasonic extraction of Chinese herbal medicines is 40-60 degrees Celsius, so there is no need to equip a boiler to provide steam heating.
Is beneficial to saving energy and improving environmental pollution. More importantly, it has a protective effect on the effective components that are unstable and easy to hydrolyze or oxidize when heated.
(4) Ultrasonic extraction has wide adaptability. Ultrasonic extraction of Chinese herbal medicine is not limited by the nature and molecular weight of Chinese herbal medicine, and is suitable for most kinds.
Extraction of medicinal materials and various components.
(5) The liquid medicine extracted by ultrasonic wave has few impurities, and the effective components are easy to separate and purify.
(7) Ultrasonic extraction is simple and easy, and the equipment maintenance is convenient.
3. Ultrasonic enhanced extraction.
(1) solid-liquid extraction
Solid-liquid extraction is usually called extraction, that is, extracting useful components from materials with appropriate solvents. The traditional process method is to add them by heat treatment or mechanical stirring.
Strengthen the process. It has been found that the application of power ultrasound can significantly strengthen and improve the extraction process. The disturbance effect of ultrasonic wave increases the penetration of solvent into extracted cells,
The mass transfer process is strengthened; Another function of ultrasound is that the strong shear force generated by ultrasonic cavitation can rupture the cell wall of the medium, making it easy for cells to release the contents. exceed
Ultrasonic-enhanced solid-liquid extraction is the main reason for effective mass transfer and cell rupture, which surpasses any feasible technology in the past and obtains efficient extraction. exceed
Acoustic extraction is more effective than thermal extraction in resident institutions, and the extraction time is shortened. Most substances are extracted within 10 minutes before processing.
(2) liquid-liquid extraction
Liquid-liquid extraction involves the mass transfer process between two immiscible organic phases and water phase. The interface effect caused by ultrasonic cavitation increases.
The interface area of two phases is increased, and the turbulence effect caused by shock wave during cavitation collapse eliminates the blockage of the boundary of two-phase effect, thus improving the liquid-liquid extraction speed. correct
Ultrasonic wave plays an important role in liquid-liquid extraction system with controlled mass transfer rate.