[Editorial view of China Pharmaceutical network] plant extract refers to the product formed by applying modern extraction and separation technology to obtain and concentrate one or more components from fruits, medicinal and edible plants, Chinese herbal medicines and other raw materials. These products are widely used in pharmaceutical raw materials, health products, cosmetics, food additives and other fields. As a deep-processing product of Chinese herbal medicines, plant extraction basically has the characteristics of raw materials and Chinese herbal medicines. In addition, it is easy to control the quality and has advantages in material transportation and application. It is easy to be accepted by the international market and has a broad prospect.
(Picture source of plant extract: Baidu pictures)
China is a big exporter of plant extracts. It is understood that 80% of the plant extracts in the market are exported. However, due to the processing links, quality and quality of the extracts, China does not have the say in international pricing. According to authoritative data, since the first quarter of 2017, China's export volume of plant extracts has reached more than 300 million US dollars, and its growth has driven the overall export volume of traditional Chinese medicine up.
It is worth mentioning that China's plant extraction industry has developed rapidly, and its concept and content are not limited to using traditional Chinese herbal medicines as raw materials. At present, the plant extraction industry has formed a modern industry with Chinese herbal extracts as the core and containing useful plant extracts from all over the world, serving human health and generating good economic benefits. However, due to the complex chemical composition of traditional Chinese medicine, the extraction and separation process of traditional Chinese medicine is complicated, the separation efficiency is low, the cost is high, the environmental pollution is serious and the labor intensity is high. Therefore, it is urgent to develop new processing and extraction equipment.
The author understands that the current mainstream equipment for traditional Chinese medicine extraction includes leaching tank, multi-functional extraction tank, dynamic extraction tank and hot reflux extraction and concentration unit. The equipment structure and operation method are basically the same as the single tank equipment for oil extraction. The author understands that with the development of extraction technology, supercritical fluid extraction, ultrasonic enhanced extraction, microwave extraction and other process equipment have been launched in recent years.
(Source of pictures of equipment workshop: Baidu pictures)
According to experts in the industry, the advantages of carbon dioxide supercritical extraction are strong selectivity and high purity of the extract. It is suitable for extracting lipophilic substances with known chemical structure and small molecular weight from solid materials. The disadvantages are high operating pressure, large energy consumption and high manufacturing cost when the equipment is enlarged. It is not suitable to extract mixtures with unknown components and substances with low solubility in carbon dioxide.
Ultrasonic enhanced extraction can use the energy of ultrasonic vibration to strengthen the diffusion process, so that the solvent is easy to immerse into the solid, and the solid solute is easy to diffuse from the solid interior to the solid-liquid interface, thus accelerating the extraction process. However, due to the limitation of ultrasonic power, the economy of large-scale production is not good, and the safety of high-power ultrasonic also needs to be verified.
Microwave extraction is to use the effect of microwave on polar molecules to heat the solvent and medicinal materials, so as to break the cell wall and accelerate the extraction. However, microwave extraction is also limited by the power of microwave generation, and there are some engineering problems in enlarging the production scale.
The process equipment mentioned above are all single tank and batch extraction equipment. The overall advantages are flexible production arrangement, suitable for small batch and multi variety plant extraction, and low investment in small-scale production. The disadvantages are low overall efficiency and high production cost. Some newly developed extraction processes have technical problems when they are scaled up. Therefore, they need to be further upgraded in the future to jump out of the single tank extraction mode.
With the continuous growth of the export volume of plant extracts in China, the United States and other countries pay more attention to plant extracts, and the quality supervision is more and more strict. It is understood that high efficiency, energy saving and green have become the future trend of the extraction equipment industry. When China's extraction equipment manufacturing enterprises usher in a broad market, they also need to seize these three "future keys" to solve new process problems and create extraction equipment suitable for the needs of the industry, so as to help plant extracts better go abroad.(source: China Pharmaceutical network)