News

The extraction method of puerarin, the technological process of its extraction is as follows:

Pueraria root pulverization→water decoction→water extract→ethanol precipitation→alcoholic extract→polyamide column chromatography→water elution→concentration→standing for crystallization→crude product→refining→drying→puerarin fine product.

Cleaning and crushing refers to the removal of debris from raw materials, processing and crushing;

The water decocting process refers to decocting the kudzu root with water for 2-4 times, and concentrating the decoction liquid to a thick paste;

Ethanol precipitation refers to adding ethanol to the water extract to make the alcohol content reach 70-80%, heating to slight boiling, stirring, placing, filtering, recovering ethanol, and concentrating to obtain alcohol extract;

The adsorbent used in column chromatography is polyamide;

Water elution means that the elution solvent of polyamide column chromatography is water or hot water or water with a pH of 2-8 or water containing ethanol;

The process flow of column chromatography-water elution-concentration-placed for crystallization-crude product means that the polyamide column chromatography is a continuous chromatography of several columns. It is to add the prepared alcohol extract to the head end of a group of chromatographic columns connected by pipes, elute with water, carry out continuous chromatography through thin-layer detection, and collect the eluent at the end. After concentration, place crystallization to obtain puerarin crude product;

The requirements for column chromatography in the extraction of crude puerarin are that the polyamide used for chromatography is 14-200 mesh. The ratio of total dosage to crude drug amount is 1:1-1:3, the ratio of column diameter to height is 1:2-1:10, and the number of chromatographic columns is 2-8;

Refining means that the obtained crude product can be processed by one of the following three methods to obtain the puerarin fine product:

After dissolving the crude product, perform polyamide column chromatography again. The elution solvent is deionized water or distilled water. Select and collect the eluent, concentrate and place it for crystallization, filter the crystals, and dry to obtain the puerarin fine product. The polyamide used for refining is 60-200 mesh, the ratio of the total amount to the crude product is 5:1-20:1, the column diameter-height ratio is 1:2-1-10, and the number of chromatographic columns commonly used is 1-3 ;

The crude puerarin is heated and dissolved in an appropriate amount of water, placed for crystallization, and the crystals are collected by filtration. After repeated recrystallization for 1-5 times, drying is performed to obtain the fine puerarin;

The dried puerarin crude product is heated and dissolved in an ethanol-containing aqueous solution, filtered, placed for crystallization, filtered to collect the crystals, and dried to obtain the puerarin fine product.

Drying refers to the drying of puerarin in addition to general drying methods, there are freeze drying, spray drying and microwave drying.