阅读说明：本技术 一种从***中提取纯化***二酚的方法 (Method for extracting and purifying cannabidiol from cannabis sativa ) 是由 田汉玉 郑明辉 郑植标 罗飞 叶彬 康浦 于 2020-03-20 设计创作，主要内容包括：本发明公开了一种从大麻中提取纯化大麻二酚的方法,属于化工提取纯化领域,包括以下步骤：将大麻花叶收割、烘干并粉碎,得到净材待用；采用乙醇溶液对净材进行连续逆流提取,得到粗提液；浓缩粗提液,并冬化除杂,得冬化混合液；将冬化混合液过滤后,升温至130-150℃脱羧1-2h,得脱羧液；脱羧液用乙醇溶液进行柱层析除杂,并用乙醇溶液洗脱,得洗脱液；浓缩洗脱液,得浸膏；浸膏用溶剂过饱和溶解后降温至-30℃至-10℃,得结晶物；将结晶物用溶剂冲洗沥干,并烘干干燥,得大麻二酚干粉,该方法脱羧程度彻底、大麻二酚纯度高,几乎不含四氢大麻酚(THC)。(The invention discloses a method for extracting and purifying cannabidiol from cannabis sativa, which belongs to the field of chemical extraction and purification and comprises the following steps: harvesting, drying and crushing hemp flowers and leaves to obtain a clean material for later use; carrying out continuous countercurrent extraction on the clean material by adopting an ethanol solution to obtain a crude extract; concentrating the crude extract, and removing impurities by winterization to obtain winterization mixed solution; filtering the winterization mixed solution, heating to 130-150 ℃ for decarboxylation for 1-2h to obtain decarboxylation solution; purifying the decarboxylated solution by using an ethanol solution for column chromatography, and eluting by using the ethanol solution to obtain an eluent; concentrating the eluent to obtain an extract; dissolving the extract with solvent, and cooling to-30 deg.C to-10 deg.C to obtain crystal; washing the crystal with solvent, draining, drying to obtain dry cannabidiol powder with high decarboxylation degree and high cannabidiol purity and containing almost no Tetrahydrocannabinol (THC).)

1. A method for extracting purified cannabidiol from cannabis sativa, comprising the steps of:

(1) harvesting, drying and crushing hemp flowers and leaves to obtain a clean material for later use;

(2) carrying out continuous countercurrent extraction on the clean material by adopting an ethanol solution to obtain a crude extract;

(3) concentrating the crude extract, and winterizing to remove impurities to obtain winterized mixed liquor;

(4) after filtering the winterization mixed solution, heating to 130-150 ℃ for decarboxylation for 1-2h to obtain decarboxylation solution;

(5) performing column chromatography impurity removal on the decarboxylated solution by using an ethanol solution, and eluting by using the ethanol solution to obtain an eluent;

(6) concentrating the eluent to obtain an extract;

(7) the extract is supersaturated and dissolved by a solvent, and then cooled to-30 ℃ to-10 ℃ to obtain a crystal;

(8) and washing the crystal with a solvent, draining, drying and drying to obtain the cannabidiol dry powder.

2. The method of claim 1, wherein the harvesting, drying and pulverizing of cannabis sativa flower and leaf in step (1) comprises drying cannabis sativa flower and leaf to a moisture content of less than 5% at a temperature of 80-150 ℃ and pulverizing cannabis sativa flower and leaf to 20-80 mesh.

3. The method of claim 1, wherein the ethanol solution concentration in step (2) is 60% -95%, the ratio of ethanol solution to net material is 4-20:1, the extraction temperature is 20-40 ℃, and the extraction time is 30-120 min.

4. The method for extracting cannabidiol from cannabis sativa as claimed in claim 1, wherein the winterization temperature in step (3) is-80 ℃ to-20 ℃ and the winterization time is 5-20 h.

5. The method of claim 1, wherein the column chromatography of step (5) uses packing materials comprising one or more of macroporous resin, forward chromatography packing silica gel, and reverse chromatography packing silica gel.

6. The method of claim 5, wherein the macroporous resin comprises one or more of NM200, D101, SD300, DM11, AB-8, DM130, HPD-703, LSA-7, XDA-8.

7. The method of claim 1, wherein the concentration in step (3) and step (6) is carried out by vacuum cryoconcentration, wherein the concentration temperature in step (3) is 50-70 ℃ and the concentration temperature in step (6) is 60-70 ℃.

8. The method of claim 1, wherein the solvent concentration in step (7) is 60% -95%.

9. The method of claim 1, wherein the drying step (8) comprises vacuum belt drying, vacuum oven drying, and vacuum double cone drying at 40-65 deg.C for 1-3 h.

10. The method of claim 1, wherein the solvent used in the steps (7) and (8) comprises one of ethanol or n-hexane.

Technical Field

The invention belongs to the field of chemical extraction and purification, and particularly relates to a method for extracting and purifying cannabidiol from cannabis sativa.

Background

Cannabis is, named Cannabis plant of Cannabis family, Cannabis genus, also named hemp, China hemp, Cannabis sativa L, Chinese mugwort, and Corchorus olitorius L, and has important agricultural and medicinal value. Cannabis sativa contains a toxic component tetrahydrocannabinol which causes hallucination and can be used as a drug, and the seed is prohibited for a long time.

Because of the extremely high economic and medicinal values of the hemp, the raw material hemp specially used for industrial application is called industrial hemp for short, the tetrahydrocannabinol content in the hemp flowers and leaves in the growth period is less than three thousandth, and the hemp has no value of extracting toxic component tetrahydrocannabinol or can be directly taken as drugs for smoking, and can be legally planted in a large scale and industrially exploited and utilized.

The cannabidiol component contained in the cannabis is a phenolic compound which is not separated from other animals and plants at present, and the cannabidiol is a non-addictive component and has high medicinal value. The research shows that if cannabidiol is reasonably applied to medicine, the cannabidiol has the functions of resisting epilepsy, resisting psychosis, resisting depression, relieving pain, relieving nausea caused by cancer chemotherapy, treating asthma and the like. In recent years, scientists also find that cannabidiol is a powerful antioxidant, has the function of blocking the adverse effect of certain drugs on human nerves, and has a series of physiological activity functions of blocking breast cancer metastasis, resisting rheumatoid arthritis, resisting insomnia and the like.

In the process of separating and purifying cannabis, 86 cannabinol compounds are separated from cannabis plants, wherein tetrahydrocannabinol, cannabinol and cannabidiol account for the main proportion, and the tetrahydrocannabinol is the main addictive component in cannabis, can cause hallucinations and addiction, and is a substance which is known to determine the properties of cannabis narcotics, so that the cannabis is classified as 'narcotic' or 'narcotic' by the convention of the United nations and laws of many countries. Internationally, a marijuana variety having a tetrahydrocannabinol content of less than 0.3% is defined as "industrial marijuana" which does not have a drug utilization value, and a marijuana variety having a tetrahydrocannabinol content of more than 0.3% is defined as "drug marijuana". The cannabis which is allowed to be planted in China at present basically belongs to industrial cannabis. In the cannabinoids, tetrahydrocannabinol and cannabidiol are relatively high in content and are isomers of each other. This also makes it difficult to completely distinguish tetrahydrocannabinol from cannabidiol and completely remove tetrahydrocannabinol from the cannabidiol product using conventional methods. Therefore, in order to obtain high-purity cannabidiol, the common extraction methods include carbon dioxide supercritical extraction, nitrogen supercritical extraction, organic solvent extraction and the like, and the extraction is carried out by combining heating or ultrasonic and other operations for mixed extraction, but the common extraction methods are not high in cannabidiol purity of the final product due to the complex cannabidiol components, many similar polar components and further deepened about research for improving the extraction purity of cannabidiol.

The invention patent 'a method for extracting cannabidiol from industrial cannabis sativa leaves' (patent application number: 201610674119.6) discloses a process for preparing cannabidiol by using industrial cannabis sativa as a raw material, and the method can reduce waste of the cannabis sativa and simplify the process flow, but still has the following 3 problems: the product is impure due to incomplete decarboxylation of the raw materials, the equipment volume is large, the investment is large, the occupied area is large, the efficiency is low, and the cost is high; the extraction method is a static clearance mode, has low efficiency and is difficult to realize large-scale production; tetrahydrocannabinol is completely different from cannabidiol and it is difficult to completely remove tetrahydrocannabinol from cannabidiol products.

Therefore, there is an urgent need to develop a method for extracting cannabidiol with high purity by complete decarboxylation.

Disclosure of Invention

The invention provides a method for extracting and purifying cannabidiol from cannabis sativa, which has the advantages of thorough decarboxylation degree and high cannabidiol purity.

In order to solve the technical problems, the technical scheme adopted by the invention is a method for extracting and purifying cannabidiol from cannabis sativa, which comprises the following steps:

(1) harvesting, drying and crushing hemp flowers and leaves to obtain a clean material for later use;

(2) carrying out continuous countercurrent extraction on the clean material by adopting an ethanol solution to obtain a crude extract;

(3) concentrating the crude extract, and winterizing to remove impurities to obtain winterized mixed liquor;

(4) after filtering the winterization mixed solution, heating to 130-150 ℃ for decarboxylation for 1-2h to obtain decarboxylation solution;

(5) performing column chromatography impurity removal on the decarboxylated solution by using an ethanol solution, and eluting by using the ethanol solution to obtain an eluent;

(6) concentrating the eluent to obtain an extract;

(7) the extract is supersaturated and dissolved by a solvent, and then cooled to-30 ℃ to-10 ℃ to obtain a crystal;

(8) and washing the crystal with a solvent, draining, drying and drying to obtain the cannabidiol dry powder.

Preferably, the hemp flower and leaf is harvested, dried and crushed in the step (1), wherein the drying is carried out at the temperature of 80-150 ℃ until the water content of the hemp flower and leaf is below 5%, and the hemp flower and leaf is crushed to 20-80 meshes.

Preferably, in the step (2), the concentration of the ethanol solution is 60-95%, the feeding ratio of the ethanol solution to the net material is 4-20:1, the extraction temperature is 20-25 ℃, and the extraction time is 30-120 minutes.

Preferably, the winterization temperature in the step (3) is-80 ℃ to-20 ℃, and the winterization time is 5-20 h.

Preferably, the column chromatography in step (5) uses packing comprising one or more of macroporous resin, forward chromatography packing silica gel and reverse chromatography packing silica gel.

Preferably, the macroporous resin comprises one or more of NM200, D101, SD300, DM11, AB-8, DM130, HPD-703, LSA-7, XDA-8.

Preferably, the concentration method in the step (3) and the step (6) is vacuum low-temperature concentration, the concentration temperature in the step (3) is 50-70 ℃, and the concentration temperature in the step (6) is 60-70 ℃.

Preferably, the concentration of the solvent in the step (7) is 60-95%.

Preferably, the drying mode in the step (8) comprises vacuum belt drying, a vacuum oven and vacuum double-cone drying, wherein the drying temperature is 40-65 ℃, and the drying time is 1-3 h.

Preferably, the solvent used in the step (7) and the step (8) comprises one of ethanol or n-hexane.

The beneficial effect of this scheme does:

1. compared with the decarboxylation of the raw material before the extraction operation, the decarboxylation method has the advantages of small equipment, low operation cost, easy control, thorough decarboxylation and less time consumption;

2. the method adopts continuous countercurrent extraction, the material and the solvent are always in a flowing state in the equipment, a certain concentration gradient is always kept, the effective components are easy to separate out, the extraction rate is higher than that of the traditional static clearance extraction, and the method is suitable for industrial large-scale production;

3. the invention adopts the collection of macroporous resin and chromatographic packing, has better separation effect, can obtain cannabidiol monomers with higher content, does not contain tetrahydrocannabinol in the cannabidiol finished product, and has high purity;

4. the method has the advantages that solvents such as petroleum ether, n-hexane and dichloromethane with high cannabidiol solubility in the prior art are abandoned, ethanol with relatively low solubility is used as an extraction solvent, and an improved extraction process is combined, so that the purity of cannabidiol is improved, tetrahydrocannabinol which is a psychotoxic component in a finished product is removed, the safety of the product is guaranteed, the influence on the environment, operators and product solvent residues is reduced by using a reagent, and the environmental pollution and the injury to personnel caused in the column chromatography process are reduced;

5. the filler of the chromatographic column can be repeatedly used, the overall production cost is reduced, and the pollution of the filler waste to the environment is reduced.

Drawings

FIG. 1 is a high performance liquid chromatogram of a raw material extract according to the present invention;

FIG. 2 is a high performance liquid chromatogram of a standard cannabidiol, tetrahydrocannabinol, cannabinol, cannabigerol mixture sample of the present invention;

FIG. 3 is a high performance liquid chromatogram of cannabidiol prepared in example 1 of the present invention;

FIG. 4 is a high performance liquid chromatogram of cannabidiol prepared in example 2 of the present invention;

FIG. 5 is a high performance liquid chromatogram of cannabidiol prepared in example 3 of the present invention;

FIG. 6 shows the results of testing cannabidiol prepared in examples 1-3.

Detailed Description

The present invention is described in detail below by way of examples, it should be noted that the following examples are only for illustrating the present invention and should not be construed as limiting the scope of the present invention, and that the non-essential modifications and adjustments made by those skilled in the art according to the above disclosure still belong to the scope of the present invention.

According to an exemplary embodiment of the present invention, there is provided a method for extracting purified cannabidiol from cannabis, the method comprising the steps of:

(1) harvesting, drying and crushing hemp flowers and leaves to obtain a clean material for later use; the invention adopts the flower and leaf powder of industrial hemp as raw materials, and the raw materials can be directly purchased commercially or obtained from industrial hemp plants through the steps of drying, grinding, sieving and the like. In some embodiments, the over-sized particles of the powder having an average particle size of 20-80 mesh are not easily extracted, are too fine to increase the load on the subsequent filtration section, and are dried for storage and to increase the extraction yield.

(2) Carrying out continuous countercurrent extraction on the clean material by adopting an ethanol solution to obtain a crude extract; in some embodiments, the concentration of the ethanol solution is 60-95%, the feeding ratio of the ethanol solution to the net material is 4-20, the mass ratio of the solvent amount to the material is indicated, the extraction temperature is 20-40 ℃, the extraction time is 30-120 minutes, the extraction is completed, the extract is collected, the parameters of related substances of the high performance liquid chromatography are obtained as shown in figure 1, then the high performance liquid chromatography detection is carried out on a standard product as shown in figure 2, the peak time and the concentration corresponding to each component can be obtained, the reference is made for the subsequent determination of the content and the concentration of the cannabidiol, the equipment used in the continuous countercurrent extraction is a continuous countercurrent extraction unit with the model number of ND50-1000, the ethanol solution is an extraction solvent, the safety of the product is guaranteed, and the used reagent reduces the influence on the environment, operators and the residual product solvent, and reduces the environmental pollution caused in the column chromatography process, injury to personnel.

(3) Concentrating the crude extractive solution, performing winterization and impurity removal to obtain winterization mixed solution, freezing the concentrated solution for winterization and impurity removal, wherein in some embodiments, the concentration method is vacuum low-temperature concentration, the concentration temperature is 50-70 ℃, the winterization temperature is-80 ℃ to-20 ℃, the winterization time is 5-20h, impurities can be separated out during winterization, namely freezing, and the winterization mixed solution is filtered and impurity removed to obtain winterization clear solution.

(4) And filtering the winterization mixed solution, heating to 130-150 ℃ for decarboxylation for 1-2h to obtain a decarboxylation solution, wherein the decarboxylation step can convert the cannabidiolic acid in the extracting solution into cannabidiol, so that the cannabidiol yield is increased. The time and temperature of decarboxylation need to be selected to obtain a material suitable for subsequent processing. Excessive temperatures can cause some active substances to decompose, evaporate, and even carbonize; the decarboxylation operation is moved backwards, compared with the decarboxylation of the raw materials before the extraction operation, the method has the advantages of small equipment, low operation cost, easy control, thorough decarboxylation and less time consumption;

(5) performing column chromatography impurity removal on the decarboxylated solution by using an ethanol solution, and eluting by using the ethanol solution to obtain an eluent; the elution step is as follows: washing with 30-70% ethanol to remove impurities, eluting with 50-90% ethanol to obtain target product, and eluting with 90-95% ethanol to regenerate column. Collecting eluate, vacuum concentrating to obtain extract, and subjecting the extract to reverse chromatographic column C18, wherein the eluting step comprises washing with 30% ethanol to remove impurities, eluting with 70% ethanol to obtain target product, and regenerating the column with 95% ethanol; the filler used in the column chromatography comprises one or more of macroporous resin, forward chromatography filler silica gel and reverse chromatography filler silica gel, wherein the macroporous resin comprises one or more of NM200, D101, SD300, DM11, AB-8, DM130, HPD-703, LSA-7 and XDA-8, and the gradient elution step not only ensures that the target product has high partial purity, but also ensures that the chromatography column is continuously regenerated and can be recycled.

(6) Concentrating the eluent to obtain an extract, wherein the concentration method is vacuum low-temperature concentration, the concentration temperature is 60-70 ℃, and the solid content of the extract is 10% -15%;

(7) the extract is supersaturated and dissolved by a solvent, and then cooled to-30 ℃ to-10 ℃ to obtain a crystal, wherein the concentration of the solvent is 60-95%;

(8) and washing the crystal with a solvent, draining, drying and drying to obtain the cannabidiol dry powder, wherein the drying mode comprises vacuum belt drying, a vacuum oven and vacuum double-cone drying, the drying temperature is 40-65 ℃, and the drying time is 1-3 h.

Hereinafter, the technical solution of the present invention will be specifically described by some embodiments and drawings, but these embodiments are merely illustrative and should not be construed as limiting the present invention.