Preparation method of honeysuckle flower extract with high chlorogenic acid content

Abstract

The invention provides a preparation method of a honeysuckle flower extract with high chlorogenic acid content, and belongs to the technical field of traditional Chinese medicine preparations, the preparation method comprises the following steps: taking a honeysuckle flower medicinal material, carrying out water extraction, concentrating the obtained extracting solution, adding an alcohol-water mixture, carrying out alcohol precipitation, filtering, directly adding lime milk into the filtrate, and carrying out alkali regulation to obtain the honeysuckle flower extract with high chlorogenic acid content. And sequentially carrying out acid regulation, filtration, neutralization, filtration and drying on the obtained precipitate to obtain the honeysuckle flower extract with high chlorogenic acid content. Alcohol precipitation is added before lime milk alkali adjustment is carried out on the concentrated extracting solution, impurities in a system are removed, meanwhile, chlorogenic acid components are protected through an alcoholic solution, damage of lime milk to the chlorogenic acid components in the alkali adjustment process is reduced, and the purity of the chlorogenic acid components is improved. The chlorogenic acid content and the chlorogenic acid transfer rate in the finally prepared honeysuckle flower extract are effectively improved.

Description

Technical Field

[0001] This invention relates to the field of traditional Chinese medicine preparation, and in particular to a method for preparing a honeysuckle extract with high chlorogenic acid content. Background Technology

[0002] Honeysuckle, as defined in the 2020 edition of the Chinese Pharmacopoeia, refers to the dried flower buds or newly opened flowers of *Lonicera japonica* Thunb., a plant belonging to the genus *Lonicera* in the family Caprifoliaceae. It is harvested and dried before flowering in early summer. Honeysuckle possesses properties such as clearing heat and detoxifying, and relieving exterior syndromes with its cooling and pungent properties. It also exhibits good antibacterial and anti-inflammatory effects. Its main components are chlorogenic acid and osmanthus extract. Honeysuckle extract is used in suppositories, lotions, injections, tablets, and capsules.

[0003] In products such as Yinhuang pills, Yinhuang tablets, Yinhuang granules, Yinhuang injection, Yinzhihuang injection, and Yinzhihuang capsules, honeysuckle extract is generally prepared by decocting with water, concentrating under reduced pressure, and drying, or by decocting with water, concentrating under reduced pressure, adjusting pH, and then concentrating and drying. Honeysuckle extracts prepared using these methods tend to have relatively high levels of impurities and low chlorogenic acid content, which cannot meet the production requirements of some current products.

[0004] "Comparative Study on Chlorogenic Acid from Different Extraction Methods of Honeysuckle", Lin Dan et al., Research and Development of Natural Products, 2003, 15(2), 124-126. This paper compares the preparation methods of honeysuckle extract (including water extraction, water extraction and alcohol precipitation, enzymatic hydrolysis, alcohol extraction, etc.) and their technical effects. The chlorogenic acid content in the honeysuckle extract obtained is not higher than 15.28%, the obtained extract is dark in color, and the clarity is low after reconstitution.

[0005] "Process Reform for the Preparation of Honeysuckle Extract for Injection", Chen Yan et al., Chinese Patent Medicine, 2006 (Issue 12), 1816-18174. This paper compares the preparation of honeysuckle extract using lime sulfur method, ethyl acetate extraction method, gelatin detanning + ethyl acetate extraction method, and ethyl acetate extraction + ultrafiltration method. It concludes that ethyl acetate extraction method can obtain extracts with high chlorogenic acid content. However, this process requires the use of ethyl acetate extraction, and the solvent residue in the obtained honeysuckle extract has a safety impact on product quality.

[0006] Chinese invention patent application CN 108785358A discloses a method for obtaining honeysuckle extract with an organic acid content (the sum of chlorogenic acid, isochlorogenic acid A, and isochlorogenic acid C) >30% using water extraction, concentration, acid precipitation, and drying. However, the medicinal materials used in its preparation need to be pulverized before extraction, and the slow pulverization process and extraction liquid release process restrict industrial production. Furthermore, the extract is pH adjusted with acetic acid and kept at a constant temperature, and chlorogenic acid, the main component of honeysuckle extract, is easily degraded when stored above 60°C. In this invention, temperature control is only involved in the extraction and drying processes, and the drying temperature is controlled below 60°C.

[0007] Chinese invention patent CN114601857B proposes to obtain honeysuckle extract with a chlorogenic acid content of not less than 26% by means of alcohol extraction, concentration, chloroform extraction and drying. The refining process uses chloroform extraction. Chloroform is volatile and belongs to Group 2B of carcinogens published by the International Agency for Research on Cancer of the World Health Organization. It is also listed in the list of toxic and harmful water pollutants and the list of key new pollutants under control. The use of chloroform in the production of honeysuckle extract increases the production process supervision costs of industrial production enterprises and the health hazards to employees.

[0008] Chinese invention patent application CN104418742A describes a process involving water extraction, membrane separation, nanofiltration concentration, macroporous resin adsorption and elution, and polyamide refining to obtain a honeysuckle extract with a chlorogenic acid purity of over 98%. Although the obtained chlorogenic acid has a high purity, the process is complex, the production cycle is long, and the maintenance costs of the membranes, nanofiltration, macroporous resins, and polyamides used are relatively high.

[0009] Chinese invention patent application No. 115957248A (hereinafter referred to as the reference document) describes a method for collecting chlorogenic acid through acid extraction, lime milk alkali conditioning, and acid conditioning again. The precipitate generated during the acid conditioning process undergoes a second acid dissolution and neutralization, and the chlorogenic acid in the filtrate is further extracted by adsorption and elution using macroporous resin. While this method can further improve the chlorogenic acid transfer rate, its overall process is complex, has a long production cycle, and incurs high maintenance costs for macroporous resins. Furthermore, the significant decomposition of chlorogenic acid during the acid extraction and alkali conditioning processes limits the potential for further improvement in the chlorogenic acid transfer rate. Summary of the Invention

[0010] To address the above problems, this invention provides a method for preparing honeysuckle extract with high chlorogenic acid content.

[0011] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0012] A method for preparing a honeysuckle extract with high chlorogenic acid content, wherein the method involves extracting honeysuckle medicinal material with water, concentrating the resulting extract, adding an alcohol-water mixture for alcohol precipitation, filtering, directly adding lime milk to the filtrate for alkali adjustment, and subjecting the resulting precipitate to acid adjustment, filtration, neutralization, filtration, and drying in sequence to obtain the honeysuckle extract with high chlorogenic acid content.

[0013] Furthermore, during the alcohol precipitation process, the alcohol content of the system obtained after adding the alcohol-water mixture is 70-90%.

[0014] Furthermore, lime milk is a turbid liquid prepared by dispersing a combination of calcium chloride and hydroxide, calcium oxide, calcium hydroxide, or quicklime in water, with a concentration of 10–40 wt%.

[0015] Furthermore, the alcohol-water mixture is an aqueous solution of ethanol with a concentration of 85-95%.

[0016] Furthermore, the specific steps of the preparation method are as follows:

[0017] S1. Take honeysuckle medicinal material, add water and decoct, concentrate the extract, add alcohol-water mixture for alcohol precipitation, filter, and obtain filtrate;

[0018] S2. While stirring, add lime milk to the filtrate to adjust the pH to alkaline, and separate the precipitate;

[0019] S3. Take the precipitate and add it to a hydrophilic solvent to disperse it. Then, add an acid solution while stirring to adjust the pH value to acidic. Filter the solution, adjust the pH value of the filtrate to neutral again, filter, concentrate, and dry to obtain the honeysuckle extract with high chlorogenic acid content.

[0020] Furthermore, in step S3, the hydrophilic solvent is water, ethanol, an aqueous solution of ethanol, methanol, or an aqueous solution of methanol.

[0021] Furthermore, in step S2, the alkaline pH value is 10-12;

[0022] In step S3, the acidic pH value is 2-5, and the neutral pH value is 6-8.

[0023] Furthermore, in step S3, the acid solution is an aqueous solution of sulfuric acid with a concentration of 30-80 wt%.

[0024] Furthermore, in step S1, the concentration is achieved through membrane filtration concentration.

[0025] In step S3, the concentration is achieved through membrane filtration concentration.

[0026] Furthermore, in step S1, the decoction is performed 1 to 5 times, and the amount of water added is 5 to 30 times the weight of the honeysuckle medicinal material.

[0027] The beneficial effects of the method for preparing honeysuckle extract with high chlorogenic acid content of the present invention are as follows:

[0028] This invention adds alcohol precipitation before alkali conditioning with lime milk to the concentrated extract, which removes impurities from the system and protects the chlorogenic acid component with the alcohol solution. This reduces the damage of lime milk to chlorogenic acid components during alkali conditioning and effectively improves the chlorogenic acid content and chlorogenic acid transfer rate in the final honeysuckle extract.

[0029] This invention avoids the destruction of chlorogenic acid during the extraction process by controlling the ethanol content, thus effectively preserving the chlorogenic acid components in honeysuckle extract.

[0030] This invention effectively protects the transformation of chlorogenic acid components in an alkaline environment (lime milk pH adjustment process) by adding alcohol precipitation to the concentrated extract. Compared with the honeysuckle extract preparation process without alcohol precipitation protection, the chlorogenic acid transfer rate can reach more than 30% while slightly increasing the yield of the paste powder.

[0031] This invention is simple to operate, and no other organic solvents other than alcohol solvents are involved. It has relatively low requirements for production equipment and relatively reduces management costs in terms of production safety, environmental safety, and enterprise process supervision.

[0032] This invention uses membrane filtration for concentration, avoiding the destruction of chlorogenic acid caused by traditional heating and solvent evaporation methods, and further preserves the chlorogenic acid components in honeysuckle extract;

[0033] This invention effectively controls the chlorogenic acid content to above 25%, which reduces impurities in honeysuckle extract to a certain extent. It can also meet the production needs of some pharmaceutical products. Moreover, the production process is relatively simple and the production cycle is short, making it suitable for large-scale industrial production. Detailed Implementation

[0034] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0035] Example 1: A method for preparing a honeysuckle extract with high chlorogenic acid content

[0036] This embodiment describes a method for preparing a honeysuckle extract with high chlorogenic acid content. The specific preparation process includes the following steps:

[0037] S1. Weigh 150g of cleaned honeysuckle, add 15 times and 5 times the amount of water to decoct twice, combine the extracts, concentrate to 300mL by membrane filtration, add 95% ethanol until the alcohol content of the obtained system is 80% (the volume of the system is about 1900mL), filter, and obtain filtrate with a volume of about 1800mL.

[0038] S2. Add 20wt% lime milk (i.e., turbid calcium oxide water solution with a concentration of 20wt%) to the filtrate while stirring, adjust the pH value to 11.9, and then separate the precipitate by centrifugation to obtain 223.50g.

[0039] S3. Add all the precipitate to 670.5 mL of ethanol, stir to disperse into a suspension, then add 50 wt% sulfuric acid aqueous solution to adjust the pH to 3.0 while stirring, filter, and adjust the pH of the filtrate to 6.9 again with 20 wt% sodium hydroxide aqueous solution, filter, concentrate by membrane filtration, and dry to obtain 21.37 g of honeysuckle extract with 27.20% chlorogenic acid content, yield of 14.25%, and chlorogenic acid transfer rate of 35.29%.

[0040] In this invention, the chlorogenic acid transfer rate is the same as the chlorogenic acid extraction rate in the reference document.

[0041] Examples 2-5: Preparation methods of honeysuckle extracts with high chlorogenic acid content

[0042] Examples 2-5 are methods for preparing honeysuckle extract with high chlorogenic acid content. Their steps are basically the same as in Example 1, differing only in the amount of raw materials and process parameters. See Table 1 for details.

[0043] Table 1. Summary of process parameters in Examples 2-5

[0044]

[0045] The contents of other parts of Examples 2 to 5 are the same as those of Example 1, and will not be repeated here.

[0046] Comparative Examples 1-8

[0047] Comparative Examples 1-8 are comparative experiments on the preparation methods of honeysuckle extract with high chlorogenic acid content in Example 1, and the same batch of honeysuckle as in Example 1 is used as raw material, as detailed below:

[0048] The steps for Comparative Example 1 are as follows:

[0049] S1. Weigh 150g of cleaned honeysuckle, add 15 times and 5 times the amount of water to decoct twice, combine the extracts and concentrate them to 300mL by membrane filtration. Add 20wt% lime milk (calcium oxide aqueous suspension) directly to the concentrate without alcohol precipitation, adjust the pH to 11.9, and then centrifuge to obtain 251.8g of precipitate.

[0050] S2. Add all the precipitate to 755.4 mL of ethanol, stir to disperse into a suspension, then add 50 wt% sulfuric acid aqueous solution to adjust the pH to 3.0 while stirring, filter, and adjust the pH of the filtrate to 6.9 again with 20 wt% sodium hydroxide aqueous solution, filter, concentrate by membrane filtration, and dry to obtain 13.50 g of honeysuckle extract with a chlorogenic acid content of 19.90%, a yield of 9.00%, and a chlorogenic acid transfer rate of 16.31%.

[0051] The steps for Comparative Example 2 are as follows:

[0052] S1. Weigh 150g of cleaned honeysuckle, add 15 times and 5 times the amount of water to decoct twice, combine the extracts and concentrate directly under reduced pressure to 300mL. Without alcohol precipitation, add 20wt% lime milk (calcium oxide aqueous suspension) to the concentrate while stirring, adjust the pH to 11.9, and then centrifuge to separate 270.3g of precipitate.

[0053] S2. Add all the precipitate to 810.9 mL of ethanol, stir to disperse into a suspension, then add 50 wt% sulfuric acid aqueous solution to adjust the pH to 3.0 while stirring, filter, and adjust the pH of the filtrate to 6.9 again with 20 wt% sodium hydroxide aqueous solution, filter, concentrate the filtrate under reduced pressure, and dry to obtain 14.3 g of honeysuckle extract with a chlorogenic acid content of 17.80%, a yield of 9.53%, and a chlorogenic acid transfer rate of 15.45%.

[0054] The steps for Comparative Example 3 are as follows:

[0055] S1. Weigh 150g of cleaned honeysuckle, decoct twice with 15 times and 5 times the amount of water respectively, combine the extracts and concentrate them to 300mL by membrane filtration, then add 95% ethanol to the system until the alcohol content is 80% (the volume of the system is about 1900mL), filter, concentrate the filtrate under low temperature and reduced pressure (45℃) until there is no alcohol taste, then add water again to the volume of about 1800mL to obtain solution A;

[0056] S2. 20wt% lime milk (calcium oxide aqueous suspension) was added to solution A under stirring to adjust the pH value to 11.9, and then the precipitate of 251.7g was separated by centrifugation.

[0057] S3. Add all the precipitate to 755.1 mL of ethanol, stir to disperse into a suspension, then add 50 wt% sulfuric acid aqueous solution to adjust the pH to 3.0 while stirring, filter, and adjust the pH of the filtrate to 6.9 again with 20 wt% sodium hydroxide aqueous solution, filter, concentrate by membrane filtration, and dry to obtain 11.32 g of honeysuckle extract with 19.70% chlorogenic acid content, yield 7.55%, and chlorogenic acid transfer rate 13.54%.

[0058] The steps for Comparative Example 4 are as follows:

[0059] S1. Weigh 150g of cleaned honeysuckle, decoct twice with 15 times and 5 times the amount of water respectively, combine the extracts and concentrate them to 300mL by membrane filtration, then add 95% ethanol until the alcohol content of the obtained system is 80% (the volume of the system is about 1900mL), filter, and concentrate the filtrate under low temperature and reduced pressure (45℃) until there is no alcohol taste, to obtain solution A;

[0060] S2. Add 20wt% lime milk (calcium oxide aqueous suspension) directly to solution A while stirring, adjust the pH value to 11.9, and then separate the precipitate by centrifugation to obtain 252.3g.

[0061] S3. Add all the precipitate to 756.9 mL of ethanol, stir to disperse into a suspension, then add 50 wt% sulfuric acid aqueous solution to adjust the pH to 3.0 while stirring, filter, and adjust the pH of the filtrate to 6.9 again with 20 wt% sodium hydroxide aqueous solution, filter, concentrate by membrane filtration, and dry to obtain 12.50 g of honeysuckle extract with 22.30% chlorogenic acid content, yield 8.33%, and chlorogenic acid transfer rate 16.92%.

[0062] The steps in Comparative Example 5 are as follows:

[0063] S1. Weigh 150g of cleaned honeysuckle, decoct twice with 15 times and 5 times the amount of water respectively, combine the extracts and concentrate them to 300mL by membrane filtration, then add 95% ethanol to make the alcohol content of the obtained system 80% (the volume of the system is about 1900mL), filter, concentrate the filtrate under low temperature and reduced pressure (45℃) until there is no alcohol taste, then add 95% ethanol and water again to adjust to the alcohol content 80% and the volume of about 1800mL to obtain solution A;

[0064] S2. 20wt% lime milk (calcium oxide aqueous suspension) was added to solution A under stirring to adjust the pH value to 11.9, and then the precipitate was separated by centrifugation, yielding 222.3g.

[0065] S3. Add all the precipitate to 666.9 mL of ethanol, stir to disperse into a suspension, then add 50 wt% sulfuric acid aqueous solution to adjust the pH to 3.0 while stirring, filter, and adjust the pH of the filtrate to 6.9 again with 20 wt% sodium hydroxide aqueous solution, filter, concentrate by membrane filtration, and dry to obtain 21.14 g of honeysuckle extract with 25.88% chlorogenic acid content, yield of 14.09%, and chlorogenic acid transfer rate of 33.22%.

[0066] The steps for Comparative Example 6 are as follows:

[0067] S1. Weigh 150g of cleaned honeysuckle, add 15 times and 5 times the amount of water to decoct twice, combine the extracts, concentrate under low temperature and reduced pressure (45℃) to 300mL, then add 95% ethanol to the system until the alcohol content is 80% (the volume of the system is about 1900mL), filter to obtain filtrate, the volume of filtrate is about 1800mL.

[0068] S2. Add 20wt% lime milk (calcium oxide aqueous suspension) to the filtrate while stirring, adjust the pH value to 11.9, and then separate the precipitate by centrifugation to obtain 223.10g.

[0069] S3. Add all the precipitate to 669.3 mL of ethanol, stir to disperse into a suspension, then add 50 wt% sulfuric acid aqueous solution to adjust the pH to 3.0 while stirring, filter, and adjust the pH of the filtrate to 6.9 again with 20 wt% sodium hydroxide aqueous solution, filter, concentrate under low temperature and reduced pressure (45℃), dry, and obtain 20.98 g of honeysuckle extract, with a chlorogenic acid content of 25.12%, a yield of 13.99%, and a chlorogenic acid transfer rate of 32.00%.

[0070] The steps for Comparative Example 7 are as follows:

[0071] Weigh 150g of cleaned honeysuckle, decoct twice with 15 times and 5 times the amount of water respectively, combine the extracts and concentrate them to 300mL by membrane filtration, then add 95% ethanol to make the alcohol content of the resulting system 80% (the volume of the system is about 1900mL), filter, concentrate the filtrate under low temperature and reduced pressure (45℃) until there is no alcohol taste, then add 95% ethanol and water again to adjust to make the alcohol content 50% and the volume about 635mL to obtain solution A;

[0072] 20wt% lime milk (calcium oxide aqueous suspension) was added to solution A while stirring to adjust the pH to 11.9, and then the precipitate was separated by centrifugation, yielding 232.7g.

[0073] All the precipitate was added to 698.1 mL of ethanol and stirred to disperse it into a suspension. Then, while stirring, 50 wt% sulfuric acid aqueous solution was added to adjust the pH to 3.0. The mixture was filtered, and the pH of the filtrate was adjusted again to 6.9 with 20 wt% sodium hydroxide aqueous solution. The mixture was filtered, concentrated by membrane filtration, and dried to obtain 17.87 g of honeysuckle extract with a chlorogenic acid content of 23.52%, a yield of 11.91%, and a chlorogenic acid transfer rate of 25.52%.

[0074] The steps for Comparative Example 8 are as follows:

[0075] Weigh 150g of cleaned honeysuckle, decoct twice with 15 times and 5 times the amount of water respectively, combine the extracts and concentrate them to 300mL by membrane filtration, then add 95% ethanol to make the alcohol content of the resulting system 50% (the volume of the system is about 630mL), filter, concentrate the filtrate under low temperature and reduced pressure (45℃) until there is no alcohol taste, then add 95% ethanol and water again to adjust to make the alcohol content 50% and the volume about 950mL to obtain solution A;

[0076] 20wt% lime milk (calcium oxide aqueous suspension) was added to solution A under stirring to adjust the pH to 11.9, and then the precipitate was separated by centrifugation, yielding 242.3g.

[0077] All the precipitate was added to 726.9 mL of ethanol and stirred to disperse it into a suspension. Then, while stirring, 50 wt% sulfuric acid aqueous solution was added to adjust the pH to 3.0. The mixture was filtered, and the pH of the filtrate was adjusted again to 6.9 with 20 wt% sodium hydroxide aqueous solution. The mixture was filtered, concentrated by membrane filtration, and dried to obtain 16.38 g of honeysuckle extract with a chlorogenic acid content of 21.30%, a yield of 10.92%, and a chlorogenic acid transfer rate of 21.18%.

[0078] By comparing Example 1 and Comparative Examples 1-8, it can be seen that in the preparation of honeysuckle extract in this invention, the concentrated extract is subjected to alcohol precipitation, and the filtrate with a certain alcohol content is alkali-adjusted using lime milk. The precipitate is then placed in ethanol for acid adjustment and filtration, followed by neutralization filtration. Throughout the preparation process, a certain alcohol content is maintained in the system. In particular, the alkali adjustment using lime milk effectively ensures that chlorogenic acid is not destroyed during the extraction process, thereby improving the chlorogenic acid content and chlorogenic acid transfer rate in the final honeysuckle extract.

[0079] Among them, comparative examples 3, 5 and 7 show that changing the alcohol content during the alkali conditioning process significantly affects the chlorogenic acid content and chlorogenic acid transfer rate in honeysuckle extract. This indicates that ethanol in the system can protect chlorogenic acid from being destroyed during the alkali conditioning process, and its ethanol content has a significant impact on the chlorogenic acid content and chlorogenic acid transfer rate in the prepared honeysuckle extract.

[0080] Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

Claims

1. A method for preparing a honeysuckle extract with a high chlorogenic acid content, characterized in that: The preparation method comprises the following steps: extracting honeysuckle medicinal materials with water, concentrating the obtained extract, adding an alcohol-water mixture for alcohol precipitation, filtering, directly adding lime milk to the filtrate for alkaline adjustment, and sequentially acid-adjusting, filtering, neutralizing, filtering, and drying the obtained precipitate to obtain the honeysuckle extract with a high chlorogenic acid content.

2. The method for preparing the honeysuckle extract with high chlorogenic acid content according to claim 1, characterized in that: During the alcohol precipitation process, the alcohol content of the system obtained after adding the alcohol-water mixture is 70-90%.

3. The method for preparing the honeysuckle extract with high chlorogenic acid content according to claim 1 or 2, characterized in that: Lime milk is a turbid liquid prepared by dispersing a combination of calcium chloride and hydroxide, calcium oxide, calcium hydroxide or quicklime in water, with a concentration of 10 to 40 wt%.

4. The method for preparing the honeysuckle extract with high chlorogenic acid content according to claim 1 or 2, characterized in that: The alcohol-water mixture is an ethanol-water solution with a concentration of 85-95%.

5. The method for preparing the honeysuckle extract with high chlorogenic acid content according to claim 1 or 2, characterized in that: The specific steps of the preparation method are as follows: S1. Take honeysuckle medicinal materials and boil them in water. After the extract is concentrated, add an alcohol-water mixture to precipitate with alcohol, filter, and obtain a filtrate; S2, adding lime milk to the filtrate to adjust the pH value to alkaline, and separating the precipitate; S3. Take the precipitate and add it to a hydrophilic solvent for dispersion, then add an acid solution to adjust the pH value to acidic, filter, adjust the pH value of the filtrate to neutral again, filter, concentrate, and dry to obtain the honeysuckle extract with a high chlorogenic acid content.

6. The method for preparing the honeysuckle extract with high chlorogenic acid content according to claim 5, characterized in that: In step S3, the hydrophilic solvent is water, ethanol, ethanol aqueous solution, methanol or methanol aqueous solution.

7. The method for preparing the honeysuckle extract with high chlorogenic acid content according to claim 5, characterized in that: In step S2, the alkaline pH value is 10 to 12; In step S3, the acidic pH value is 2-5, and the neutral pH value is 6-8.

8. The method for preparing the honeysuckle extract with high chlorogenic acid content according to claim 5, characterized in that: In step S3, the acid solution is a sulfuric acid aqueous solution with a concentration of 30-80 wt%.

9. The method for preparing the honeysuckle extract with high chlorogenic acid content according to claim 5, characterized in that: In step S1, the concentration is membrane filtration concentration; In step S3, the concentration is membrane filtration concentration.

10. The method for preparing the honeysuckle extract with high chlorogenic acid content according to claim 5, characterized in that: In step S1, the number of decoctions is 1 to 5 times, and the amount of water added is 5 to 30 times the weight of the honeysuckle medicinal material.

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