Method for simultaneously extracting alkaloid and flavone from motherwort herb residues

Abstract

The invention discloses a method for simultaneously extracting alkaloid and flavone from motherwort herb residues, and belongs to the technical field of traditional Chinese medicine extraction. The method comprises the following steps: (a) taking motherwort herb residues, adding an extraction solvent for extraction, collecting an extracting solution, and filtering; (b) concentrating the supernate under reduced pressure to obtain a concentrated solution; (c) extracting the concentrated solution and an extracting solvent, and taking a lower-layer water solution; and (d) carrying out vacuum concentration on the lower-layer water liquid, and drying to obtain the motherwort herb residue extract. According to the method disclosed by the invention, not only is the waste motherwort herb residues comprehensively utilized, the waste of traditional Chinese medicine resources and the environmental pollution are reduced, but also the motherwort extract with higher alkaloid and flavone contents is obtained by using a process which is relatively simple, low in cost and suitable for industrialization.

Description

Technical Field

[0001] This invention belongs to the field of traditional Chinese medicine extraction technology, specifically relating to a method for simultaneously extracting alkaloids and flavonoids from the residue of Leonurus japonicus. Background Technology

[0002] Motherwort is a plant belonging to the Lamiaceae family. Leonurus japonicas The fresh or dried aerial parts of *Houtt.* possess the effects of promoting blood circulation and regulating menstruation, promoting diuresis and reducing swelling, and clearing heat and detoxifying. Clinically, it is often used to treat gynecological diseases such as irregular menstruation, dysmenorrhea, amenorrhea, lochia retention, postpartum pain, edema, and oliguria, and is hailed as a "good medicine for menstruation and childbirth." In addition to human medicinal use, *Leonurus japonicus* and its extracts are widely used in health foods, cosmetics, veterinary drugs, and feed additives.

[0003] Currently, over 200 kinds of medicines containing motherwort are used clinically, with an annual usage of 50,000 to 100,000 tons of the herb and 100,000 to 200,000 tons of waste residue. This waste residue is typically disposed of through landfill or incineration, not only consuming land resources but also polluting the air and water. Furthermore, the production processes for motherwort products with high usage, such as motherwort granules, capsules, extracts, and formula granules, all rely on water decoction extraction. This results in low extraction rates for less soluble and less potent components; even the transfer rate of stachydrine hydrochloride is only around 60%. Besides the alkaloids, which have been extensively studied, motherwort also contains flavonoids and terpenes. Studies have shown that motherwort flavonoids have effects such as anti-myocardial ischemia, promoting myocardial contractility, stimulating the uterus, and antibacterial activity. These are primarily fat-soluble flavonoids, which are difficult to extract effectively using only water; discarding them directly would result in a significant waste of resources.

[0004] Existing technologies mostly extract alkaloids directly from motherwort, without research on the residue. Chinese patent application CN 101244121A uses a combination of weakly acidic cation exchange resin, strongly acidic cation exchange resin, and neutral alumina to purify motherwort extract to obtain a total alkaloid extract. Chinese patent application CN104367622A uses ethanol soaking, ultrasonic washing, and resin filtration to concentrate motherwort extract, followed by elution with hydrochloric acid and activated carbon in a water bath, and then concentration to obtain motherwort alkaloids. These methods primarily target alkaloids but are not suitable for extracting and refining residual flavonoids in the residue, and are complex and unsuitable for industrial production. Summary of the Invention

[0005] Therefore, the application provides a method for simultaneously extracting alkaloids and flavones from motherwort residues, which realizes the reuse of the motherwort residues, reduces the waste of medicinal material resources and environmental pollution, and obtains the motherwort extract with high effective component content by using a simple process and low production cost, thereby providing a thought for the application of the motherwort byproducts in cosmetics, veterinary drugs or feed additives.

[0006] The object of the application is achieved by the following technical scheme. The application provides a method for simultaneously extracting alkaloids and flavones from motherwort residues, which comprises the following steps: (a) taking the motherwort residues, adding an extraction solvent to perform extraction, collecting an extraction liquid, and filtering; (b) taking the supernatant and performing vacuum concentration to obtain a concentrated liquid; (c) performing extraction on the concentrated liquid with an extraction solvent, and taking the lower aqueous liquid; and (d) performing vacuum concentration on the lower aqueous liquid, and drying to obtain a motherwort residue extract.

[0007] Specifically, the motherwort residues are the residues after the water extraction of motherwort medicinal materials.

[0008] More specifically, the motherwort residues do not need special treatment or are appropriately extruded to have a water content of 40% to 60%.

[0009] Specifically, the extraction solvent for the residues is an ethanol solution with a volume fraction of 65% to 85%, so that the volume fraction of ethanol in the system after the addition of the extraction solvent is 60% to 80%.

[0010] Specifically, the extraction method is continuous countercurrent extraction, the mass / volume ratio of the material to the liquid is 6 times to 10 times, the extraction temperature is controlled to be 75 DEG C to 85 DEG C, and the extraction time is 1.5 h to 3 h.

[0011] Specifically, the volume fraction of ethanol in the concentrated liquid in step (b) is controlled to be 20% to 30%.

[0012] Specifically, the extraction solvent in step (c) is n-hexane or petroleum ether.

[0013] Specifically, the volume ratio of the concentrated liquid to the extraction solvent in step (c) is 1:1 to 1:3, and the extraction temperature is 40 DEG C to 50 DEG C.

[0014] Specifically, in step (d), the vacuum concentration is performed to the concentrated liquid to have a relative density of 1.10 to 1.15, and the drying method is spray drying; or the vacuum concentration is performed to the concentrated liquid to have a relative density of 1.35 to 1.40, and the drying method is vacuum and reduced pressure drying.

[0015] Specifically, the weight content of alkaloids in the extract in step (d) is greater than or equal to 5%, and the weight content of flavones is greater than or equal to 5%.

[0016] This invention offers the following advantages: The method is easy to operate, with a simple process route, few steps, and low production cost, making it suitable for industrial production. It can simultaneously extract multiple active ingredients, including alkaloids, flavonoids, and terpenes, from the residue of *Leonurus japonicus* (motherwort) herbs, achieving high extraction efficiency. This invention transforms *Leonurus japonicus* residue into a valuable resource, realizing the comprehensive utilization of organic waste, reducing environmental pollution, and ensuring the rational and full utilization of traditional Chinese medicine resources. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of this invention, not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention. Example 1

[0018] A method for simultaneously extracting alkaloids and flavonoids from the residue of Leonurus japonicus includes the following steps: 100 kg of Leonurus japonicus residue was placed in a continuous countercurrent extractor. The residue had a moisture content of 60%. Six times the amount of 65% ethanol was added to maintain the ethanol concentration in the system at 60%. The extract was continuously countercurrently extracted at 85°C for 1.5 h. The extract was filtered through a plate and frame filter press and then concentrated in a double-effect concentrator to a 20% ethanol content. The concentrate was then fed into an extraction tower, where hexane was introduced at a 1:1 ratio (concentrate: hexane). The extract was countercurrently extracted once at 50°C for 30 min. The aqueous phase was then fed through the bottom of the tower into a double-effect concentrator for further concentration until a relative density of 1.1 was reached. The concentrate was then spray-dried to obtain the Leonurus japonicus residue extract, which contained 5.8 wt% alkaloids and 6.3 wt% flavonoids. Example 2

[0019] A method for simultaneously extracting alkaloids and flavonoids from the residue of Leonurus japonicus includes the following steps: 100 kg of Leonurus japonicus residue (40% moisture content) was placed in a continuous countercurrent extractor. Ten times the amount of 85% ethanol was added to maintain the ethanol concentration at 80%. The extract was continuously extracted countercurrently at 75°C for 3 hours. The extract was filtered through a plate and frame filter press and then concentrated in a double-effect concentrator to a 30% ethanol content. The concentrate was then fed into an extraction tower, where hexane was introduced at a 1:3 ratio (concentrate: hexane). The extract was then subjected to one countercurrent extraction at 40°C for 30 minutes. The aqueous phase was fed through the bottom of the tower into a double-effect concentrator for further concentration until a relative density of 1.5 was reached. The concentrate was then spray-dried to obtain the Leonurus japonicus residue extract, which contained 6.1 wt% alkaloids and 6.8 wt% flavonoids.

[0020] Example 3 A method for simultaneously extracting alkaloids and flavonoids from the residue of Leonurus japonicus includes the following steps: 100 kg of Leonurus japonicus residue (50% moisture content) was placed in a continuous countercurrent extractor. Eight times the amount of 75% ethanol was added to maintain the ethanol concentration at 70%. The extract was continuously extracted countercurrently at 82°C for 3 hours. The extract was filtered through a plate and frame filter press and then concentrated in a double-effect concentrator to a 25% ethanol content. The concentrate was then fed into an extraction tower, where hexane was introduced at a 1:2 ratio (concentrate: hexane). The mixture was extracted countercurrently once at 40°C for 30 minutes. The aqueous phase was then fed to a double-effect concentrator at the bottom of the tower for further concentration until a relative density of 1.3 was reached. The concentrate was then spray-dried to obtain the Leonurus japonicus residue extract, which contained 6.3 wt% alkaloids and 7.1 wt% flavonoids. Example 4

[0021] A method for simultaneously extracting alkaloids and flavonoids from the residue of Leonurus japonicus includes the following steps: 100 kg of Leonurus japonicus residue (50% moisture content) was placed in a continuous countercurrent extractor. Eight times the volume of 75% ethanol was added to maintain the ethanol concentration at 70%. The extract was continuously extracted countercurrently at 82°C for 3 hours. The extract was filtered through a plate and frame filter press and then concentrated in a double-effect concentrator to a 25% ethanol content. The concentrate was then fed into an extraction tower, where petroleum ether was introduced at a 1:3 ratio (concentrate:petroleum ether). The extract was then subjected to one countercurrent extraction at 50°C for 30 minutes. The aqueous phase was fed through the bottom of the tower into a double-effect concentrator for further concentration until a relative density of 1.38 was reached. The concentrate was then dried under vacuum to obtain the Leonurus japonicus residue extract, which contained 6.1 wt% alkaloids and 6.7 wt% flavonoids.

Claims

1. A method for simultaneously extracting alkaloids and flavonoids from the residue of Leonurus japonicus, characterized in that, The process includes the following steps: (a) taking the residue of Leonurus japonicus, adding an extraction solvent to extract it, collecting the extract and filtering it; (b) taking the supernatant and concentrating it under reduced pressure to obtain a concentrated solution; (c) extracting the concentrated solution with an extraction solvent and taking the lower aqueous layer; (d) concentrating the lower aqueous layer under reduced pressure and drying it to obtain the Leonurus japonicus residue extract.

2. The method for simultaneously extracting alkaloids and flavonoids from the residue of Leonurus japonicus according to claim 1, characterized in that, The motherwort residue is the residue after the motherwort herb has been extracted with water.

3. The method for simultaneously extracting alkaloids and flavonoids from the residue of Leonurus japonicus according to claim 2, characterized in that, The residue of motherwort does not require special treatment or proper squeezing to keep the moisture content between 40% and 60%.

4. The method for simultaneously extracting alkaloids and flavonoids from the residue of Leonurus japonicus according to claim 1, characterized in that, The extraction solvent is an ethanol solution with a volume fraction of 65% to 85%, and after adding the extraction solvent, the volume fraction of ethanol in the system is 60% to 80%.

5. The method for simultaneously extracting alkaloids and flavonoids from the residue of Leonurus japonicus according to claim 1, characterized in that, The extraction method is continuous countercurrent extraction, the material-to-liquid mass-to-volume ratio is 6 to 10, the extraction temperature is controlled at 75℃ to 85℃, and the extraction time is 1.5 h to 3 h.

6. The method for simultaneously extracting alkaloids and flavonoids from the residue of Leonurus japonicus according to claim 1, characterized in that, The volume fraction of ethanol in the concentrate in step (b) is controlled at 20% to 30%.

7. The method for simultaneously extracting alkaloids and flavonoids from the residue of Leonurus japonicus according to claim 1, characterized in that, The extraction solvent in step (c) is n-hexane or petroleum ether.

8. The method for simultaneously extracting alkaloids and flavonoids from the residue of Leonurus japonicus according to claim 1, characterized in that, Step (c) Concentrate: The volume ratio of the extraction solvent is 1:1 to 1:3, and the extraction temperature is 40℃ to 50℃.

9. The method for simultaneously extracting alkaloids and flavonoids from the residue of Leonurus japonicus according to claim 1, characterized in that, In step (d), the concentration is carried out under reduced pressure until the relative density of the concentrate is 1.10 to 1.15, and the drying method is spray drying; or the concentration is carried out until the relative density of the concentrate is 1.35 to 1.40, and the drying method is vacuum drying.

10. The method for simultaneously extracting alkaloids and flavonoids from Leonurus japonicus residue according to claim 1, characterized in that, The extract described in step (d) contains ≥5% by weight of alkaloids and ≥5% by weight of flavonoids.