Efficient preparation method of sophora alopecuroide alkaloid
By using a very small amount of alkali solution to moisten the medicinal powder of bitter bean medicinal material and performing an organic solvent extraction, the problems of low efficiency and high cost of preparation of bitter bean alkaloids in the prior art are solved, and efficient and low-cost alkaloid extraction is achieved The effect is to achieve the goal of alkaloid content higher than 50%.
Patent Information
- Application Number
- CN202411712228.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-27
- Publication Date
- 2025-02-11
AI Technical Summary
The existing alkaloid preparation process for bitter beans has problems such as high cost, low efficiency, many extraction times and many water-soluble impurities, resulting in low extraction efficiency and purity of alkaloids.
A very small amount of alkali solution is used to moisten the bitter bean medicinal powder, and then an organic solvent that is immiscible with water is extracted in one go to obtain a bitter bean alkaloid with a content of more than 20%. Further, 4-6 organic solvent extractions were performed to achieve the goal of alkaloid content higher than 50%.
It significantly improves the extraction efficiency and purity of bitter bean alkaloids, reduces the amount of solvent and the number of extractions, reduces production costs, and improves production efficiency.
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Figure CN119405710A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of natural drug chemistry, and more particularly to a method for preparing sophora alopecuroides alkaloids. Background Art
[0002] Bitter beans ( Sophora alopecuroides L.) is a plant of the genus Sophora in the Leguminosae family, also known as sweet bean, bitter licorice, bitter bean grass, etc. It is a perennial herb. The Ningxia Hui Autonomous Region has listed bitter beans as one of the six major traditional Chinese medicines under key protection, and has been included in the National Action Plan for Modernization of Traditional Chinese Medicine Science and Technology Industry. The distribution area of bitter beans in Ningxia is about 250,000 hectares, of which 140,000 hectares are distributed in Yanchi County, accounting for 56% of the total distribution area of bitter beans in Ningxia. It is a regional medicinal plant unique to Ningxia.
[0003] Studies have shown that the root, stem, whole herb and seeds of Sophora alopecuroides can be used as medicine. They are bitter and cold in nature, and have the effects of clearing away heat and detoxifying, dispelling wind and dampness, killing insects and relieving pain. The main chemical components of Sophora alopecuroides include alkaloids, flavonoids, organic acids, amino acids and polysaccharides, among which alkaloids are the main active ingredients in Sophora alopecuroides. The total alkaloid content of Sophora alopecuroides is about 6.11%-8.03%, and the seeds contain about 8.11%. The main medicinal developments include Matrine, Oxymatrine, Sophocarpine, Oxysophocarpine, Sophoramine, Sophoridine, Lehmannine, Aloperine, etc. The main pharmacological effects of Sophora alopecuroides alkaloids include central inhibitory activity, cardiovascular positive inotropic effect, liver damage protection, immunomodulatory effect, antiviral, anti-inflammatory and anti-tumor effects. In recent years, China has developed matrine injection and matrine capsules for the treatment of hepatitis B using sophora flavescens alkaloids as raw materials, sophora flavescens hydrochloride injection for gynecological tumors with sophora flavescens as the main active ingredient, as well as kexiling tablets for the treatment of intestinal infections and gynecological external preparations developed with matrine as raw material.
[0004] The existing preparation process of bitter bean alkaloids mainly adopts the following methods: ① Reflux (or cold soaking or percolation) extraction with ethanol and aqueous solution or enzyme (cellulase) extraction → discard insoluble matter after acidification → extract with organic solvent after alkalization → collect the organic layer and concentrate to dryness. ② Soak in alkaline water and add organic solvent for reflux extraction → collect the organic solvent and concentrate it, then acidify and discard insoluble matter → extract with organic solvent after alkalization → collect the organic layer and concentrate to dryness. ③ Acid water extraction → purification with cation exchange resin or macroporous adsorption resin → collect the alkali-containing ethanol solution eluate and concentrate it to dryness. ④ Extract with alkaline ethanol and aqueous solution → evaporate the ethanol and add water and weak polar organic solvent for extraction → collect the organic solvent phase layer and concentrate it to dryness.
[0005] The limitations of the above methods are as follows: ① The use of ethanol-water solution or enzyme extraction requires the use of organic solvents or cellulase, which increases the cost and requires repeated extraction to ensure complete extraction. ② The use of acid water will produce more water-soluble impurities, so cationic resin purification is generally required. However, because the alkaloids in bitter beans are too strongly bonded to the ion exchange resin, the alkaloids cannot be completely washed out even if they are eluted for a long time with a large amount of strongly alkaline ethanol-water solution, and the regeneration capacity of the resin is also difficult. ③ When an alkaline solution with a high liquid-to-solid ratio (the minimum ratio of bitter bean medicinal material mass to alkaline solution volume in the literature = 1:2) is used for leaching and then extracted with an organic solvent, the extraction efficiency is low due to the emulsification phenomenon at the interface between the water and organic solvent phases, the extraction time is long, and it takes many times to extract completely.
[0006] Based on the limitations of the above existing preparation process of sophora alopecuroides alkaloids, the present invention provides a method for obtaining sophora alopecuroides alkaloids with a content higher than 20% (HPLC determination) by wetting the sophora alopecuroides medicinal material powder with a very small amount of alkaline solution and then extracting it once with an organic solvent immiscible with water. The obtained alkaloid content is more than 4 times higher than that of the medicinal material powder mass and alkaline solution volume ratio of 1:2 used in the literature, and the time is shortened by more than 10 times, which greatly reduces the amount of extraction and extraction solvent and the number of extractions, and greatly improves the production efficiency on the basis of significantly reducing the cost. At the same time, continuing to use organic solvent extraction for 4 times can obtain sophora alopecuroides alkaloids with a content higher than 50% (HPLC determination). This paper aims to study a simple, efficient and low-cost extraction method for sophora alopecuroides alkaloids, in order to obtain a larger yield and lay a foundation for the industrial production of sophora alopecuroides alkaloids. Summary of the invention
[0007] In view of this, the present invention provides a method for preparing sophora alopecuroides alkaloids; In order to achieve the above object, the present invention adopts the following technical solution: A method for preparing sophora alopecuroides alkaloids, comprising the following steps: The dried bitter bean is used as the raw material, crushed into a suitable particle size, and then a very small amount of a strong alkaline solution of a suitable concentration is added and mixed well to make the medicinal powder uniformly moistened to a state where there is water but no dripping when held. After stirring and leaving for a certain period of time, a certain amount of an organic solvent immiscible with water is added for extraction, and the organic solvent is collected and concentrated to dryness to obtain the bitter bean alkaloid.
[0008] Furthermore, the grinding degree of the bitter bean is the coarsest powder (all can pass through a 10-mesh sieve but mixed with no more than 20% of powder that can pass through a 50-mesh sieve) or coarse powder (all can pass through a 24-mesh sieve but mixed with no more than 40% of powder that can pass through a 65-mesh sieve), preferably the coarsest powder.
[0009] The strong alkaline solution of suitable concentration refers to NaOH or ammonia solution with a pH value of 12-14, preferably a NaOH solution with a pH value of 14.
[0010] The ratio of the bitter bean to the NaOH solution is mass (g): volume (mL) = 4:1-3, preferably 4:1.
[0011] The stirring time is 10-30 min, preferably 30 min.
[0012] The standing time is 6-10 h, preferably 10 h.
[0013] Furthermore, in the preparation method, the organic solvent can be any one of dichloromethane, chloroform, petroleum ether, toluene, ether, or any combination thereof.
[0014] The above organic solvents are used for extraction 4-6 times to obtain the sophora alopecuroides alkaloids with a content greater than 50% (HPLC determination).
[0015] Further, the source of the sophora alopecuroides involved in the present invention is the sophora alopecuroides of the genus Sophora of the Leguminosae family ( Sophora alopecuroides L.) dry whole herb or seeds. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.
[0017] Figure 1 This is the process flow chart for the preparation of sophora alopecuroides alkaloids.
[0018] Figure 2 The HPLC chart of the test solution of Sophora alopecuroides, including 1-cytisine, 2-oxymatrine, 3-oxysophoridine, 4-matrine, and 5-sophorocarpine. DETAILED DESCRIPTION
[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Example 1
[0020] Take the crushed Sophora alopecuroides, weigh 3 portions of about 80 g each, place them in extraction containers, add 20 mL of NaOH solution with pH=10, pH=12, and pH=14, mix well and place at room temperature for 8 h. Then add 600 mL of dichloromethane, mix well, stir for 10 min, let stand for 30 min, filter, and concentrate the filtrate under reduced pressure to obtain crude alkaloids of Sophora alopecuroides. Weigh them, the masses are 2.09 g, 2.27 g, and 2.99 g, respectively. The total content of 5 alkaloids, including oxymatrine, matrine, sophorocarpine, cytisine, and oxysophoridine, in each crude Sophora alopecuroides alkaloids was determined by high performance liquid chromatography, and the percentages were 11.2%, 10.5%, and 22.7%, respectively. The results show that the quality and content of alkaloids obtained by extracting Sophora alopecuroides from NaOH solution with pH=14 are the highest. Example 2
[0021] Take the crushed Sophora alopecuroides, weigh 3 portions of about 80 g each, place them in extraction containers, add 20 mL, 40 mL and 60 mL of pH=12 NaOH solution, mix well and place at room temperature for 8 h. Then add 600 mL of dichloromethane, mix well, stir for 10 min, let stand for 30 min, filter, and concentrate under reduced pressure to obtain crude Sophora alopecuroides alkaloids, with masses of 2.52 g, 2.30 g and 1.67 g respectively. The total contents of oxymatrine, matrine, sophorocarpine, cytisine and oxysophoridine in the crude Sophora alopecuroides alkaloids were determined by high performance liquid chromatography, and the total contents were 12.6%, 3.1% and 2.7% respectively. The results showed that the mass and content of the obtained alkaloids were the highest when the volume ratio of Sophora alopecuroides to NaOH solution was 4:1. Example 3
[0022] Take the crushed Sophora alopecuroides, weigh 3 portions of about 80 g each, place them in extraction containers, add 20 mL of NaOH solution with pH=12, mix well and place at room temperature for 8 h. Then add 600 mL of dichloromethane, mix well, stir for 10 min, 20 min, and 30 min respectively, then stand for 30 min, filter, and concentrate the filtrate under reduced pressure to obtain crude Sophora alopecuroides alkaloids, with masses of 2.55 g, 2.81 g, and 2.54 g, respectively. The total contents of oxymatrine, matrine, sophorocarpine, cytisine, and oxysophoridine in the crude Sophora alopecuroides alkaloids were determined by HPLC, and the total contents were 6.3%, 5.8%, and 9.2%, respectively. The results showed that the content of alkaloids obtained from Sophora alopecuroides was the highest when the stirring time was 30 min. Example 4
[0023] Take 3 portions of bitter bean medicinal materials and grind them into the coarsest powder (all can pass through the 10 mesh sieve but mixed with powder that can pass through the 50 mesh sieve of no more than 20%), coarse powder (all can pass through the 24 mesh sieve but mixed with powder that can pass through the 65 mesh sieve of no more than 40%) and medium powder (all can pass through the 65 mesh sieve but mixed with powder that can pass through the 80 mesh sieve of no more than 60%). Take the bitter bean medicinal materials that are grinded into the coarsest powder, coarse powder and medium powder, weigh about 80 g each, put them in extraction containers, add 20 mL of pH=12 NaOH solution, mix well and leave at room temperature for 8 hours. Then add 600 mL of dichloromethane to each, mix well, stir for 10 minutes, let stand for 30 minutes, filter, and concentrate the filtrate under reduced pressure to obtain the crude bitter bean alkaloids, with masses of 3.26 g, 3.42 g and 2.30 g respectively. The total contents of oxymatrine, matrine, sophoracarpine, cytisine and oxysophoridine in crude alkaloids of Sophora alopecuroides were 6.5%, 6.1% and 19.9% respectively by HPLC. The results showed that the content of alkaloids was the highest when Sophora alopecuroides was crushed into the coarsest powder. Example 5
[0024] Take the crushed Sophora alopecuroides, weigh 3 portions of about 80 g each, place them in extraction containers, add 20 mL of pH=12 NaOH solution, mix well and place at room temperature for 6 h, 8 h and 10 h respectively. Then add 600 mL of dichloromethane, mix well, stir for 10 min and then place for 30 min, filter, and concentrate the filtrate under reduced pressure to obtain crude Sophora alopecuroides alkaloids, with masses of 2.50 g, 2.56 g and 2.31 g respectively. The total contents of oxymatrine, matrine, sophorocarpine, cytisine and oxysophoridine in the crude Sophora alopecuroides alkaloids were determined by HPLC, and the total contents were 5.3%, 2.6% and 6.6% respectively. The results showed that the content of alkaloids obtained when Sophora alopecuroides was soaked in NaOH solution for 10 h was the highest. Example 6
[0025] Take the crushed Sophora alopecuroides, weigh about 80 g of one portion, put it in an extraction container, add 20 mL of NaOH solution with pH=14, mix well and leave at room temperature for 10 h. Then add 600 mL of dichloromethane, mix well, stir for 10 min and let stand for 30 min, filter, and concentrate the filtrate under reduced pressure to obtain concentrated solution 1, and recover dichloromethane; add the recovered dichloromethane to the residue of Sophora alopecuroides, stir for 10 min and let stand for 30 min, filter, and concentrate the filtrate under reduced pressure to obtain concentrated solution 2, and recover dichloromethane; repeat the above steps 4 times, combine the 6 concentrated solutions, evaporate to dryness, and obtain Sophora alopecuroides alkaloids. The total content of 5 alkaloids, including oxymatrine, matrine, sophoracarpine, cytisine, and oxysophoridine, is greater than 50% by HPLC.
[0026] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.
[0027] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. A method for preparing alopecuroid alkaloids, comprising the following steps: The dried bitter bean is used as the raw material, crushed into a suitable particle size, and then a very small amount of a strong alkaline solution of a suitable concentration is added and mixed well to make the medicinal powder uniformly moistened to a state where there is water but no dripping when held. After stirring and leaving for a certain period of time, a certain amount of an organic solvent immiscible with water is added for extraction, and the organic solvent is collected and concentrated to dryness to obtain the bitter bean alkaloid.
2. The method for preparing a sophora alopecuroid alkaloid according to claim 1, characterized in that: The source of the sophora alopecuroides is the sophora alopecuroides plant of the genus Sophora in the Leguminosae family ( Sophora alopecuroides L.) dry whole herb or seeds.
3. The method for preparing a sophora alopecuroid alkaloid according to claim 1, characterized in that: The grinding degree of the bitter bean is the coarsest powder (all can pass through a 10-mesh sieve but mixed with no more than 20% of powder that can pass through a 50-mesh sieve) or coarse powder (all can pass through a 24-mesh sieve but mixed with no more than 40% of powder that can pass through a 65-mesh sieve), preferably the coarsest powder.
4. The method for preparing a sophora alopecuroid alkaloid according to claim 1, characterized in that: The strong alkaline solution of suitable concentration refers to NaOH or ammonia solution with a pH value of 12-14, preferably a NaOH solution with a pH value of 14.
5. The method for preparing a sophora alopecuroid alkaloid according to claim 1, characterized in that: The ratio of dried bitter beans to NaOH solution is mass (g): volume (mL) = 4:1-3, preferably 4:
1.
6. The method for preparing a sophora alopecuroid alkaloid according to claim 1, characterized in that: The stirring time is 10-30 min, preferably 30 min.
7. The method for preparing a sophora alopecuroid alkaloid according to claim 1, characterized in that: The standing time is 6-10 h, preferably 10 h.
8. The method for preparing a sophora alopecuroid alkaloid according to claim 1, characterized in that: The organic solvent may be any one of dichloromethane, chloroform, ethyl acetate, petroleum ether, toluene, ether, or any combination thereof.
9. The method for preparing a sophora alopecuroid alkaloid according to claim 1, characterized in that: The sophora alopecuroides alkaloids with a content greater than 50% (HPLC determination) can be obtained by extracting with an organic solvent 4-6 times.