Novel method for extracting hesperidin

Abstract

The invention discloses a novel method for extracting hesperidin. The method comprises the following steps: S1, crushing an immature bitter orange raw material; s2, preparing an organic alkali solvent with the mass concentration of 60-90%; s3, mixing the immature bitter orange raw material with the organic alkali solvent, stirring, filtering and collecting filtrate; s4, recovering an organic alkali solvent from the filtrate under a negative pressure condition, taking the recovered solvent as an extraction solvent of the next batch to obtain an extract, adding clear water into the extract, and stirring and crystallizing to obtain a crystallization solution; s5, filtering and washing the crystallization liquid to obtain a water-containing hesperidin crude product; and S6, refining the water-containing hesperidin crude product to obtain a hesperidin product. According to the method, the organic alkali solvent is adopted, hesperidin is physically dissolved at the room temperature for extraction, damage to the hesperidin structure is avoided, the extraction process is simple, operation is safe, the environment is clean, the organic alkali solvent can be recycled, the manufacturing cost is reduced, and economic benefits are improved.

Description

Technical Field

[0001] The invention relates to the technical field of plant extraction, and in particular to a novel method for extracting hesperidin. Background Art

[0002] Citrus is a widely planted fruit. During the natural growth process, 80% of the young fruits fall off naturally after flowering. The fallen fruits are rich in active ingredients such as flavonoids and alkaloids, and are widely used in Chinese herbal medicines and active ingredient extraction. Fruit farmers only need to pick them up and dry them to increase their income, so the physiological fruit drop of citrus is a good resource. Hesperidin belongs to the flavonoid compounds and is widely present in plants of the genus Citrus in the Rutaceae family. The smaller the physiological fruit drop, the higher the content; the traditional extraction methods include: hot water extraction, alkaline leaching and acid precipitation, alcohol solvent extraction, etc. Among them, the hot water extraction method is simple, but the product has many impurities and low yield; alkaline leaching and acid precipitation requires a large amount of acid and alkali, and produces by-products such as halogen salts. The purity of hesperidin extracted by the alcohol solvent extraction method is relatively high, and the alcohol can be recycled and reused repeatedly, but the energy consumption cost is high.

[0003] After years of production practice, the currently commonly used hesperidin extraction technology is the chemical extraction method. The principle of this method is to use hesperidin to open the ring under inorganic alkaline conditions to form hesperidin chalcone, and this chalcone can be dissolved in water to achieve extraction. Subsequently, through a neutralization reaction under acidic conditions, the hesperidin chalcone is closed and reduced to hesperidin. However, since the process of hesperidin opening the ring to chalcone under alkaline conditions is easily damaged by oxidation, this results in the extraction conversion rate of hesperidin being generally only 70-80%, which is a low conversion rate. Summary of the invention

[0004] In view of the above problems, the present invention aims to provide a novel method for extracting hesperidin, which extracts hesperidin by dissolving it in an organic alkaline solvent, thereby avoiding damage to the structure of hesperidin, and the organic alkaline solvent can be recycled, thereby reducing the manufacturing cost.

[0005] The technical solution of the present invention is as follows:

[0006] A novel method for extracting hesperidin comprises the following steps: S1, crushing a raw material of Citrus aurantium; S2, preparing an organic alkali solvent with a mass concentration of 60-90%; S3, mixing the raw material of Citrus aurantium and the organic alkali solvent, stirring, filtering and collecting the filtrate; S4, recovering the organic alkali solvent from the filtrate under negative pressure conditions, using the recovered solvent as the next batch of extraction solvent to obtain an extract, adding clean water to the extract, stirring and crystallizing, and obtaining a crystal liquid; S5, filtering and washing the crystal liquid to obtain a crude hydrous hesperidin product; S6, refining the crude hydrous hesperidin product to obtain a hesperidin product.

[0007] Preferably, in step S1, the Fructus Aurantii Immaturus raw material is put into a crusher and crushed to a fineness of 80-120 meshes.

[0008] Preferably, in step S2, the total volume of the organic base solvent used is 15-25 times the mass of the Fructus Aurantii Immaturus raw material.

[0009] Preferably, in step S2, the organic alkaline solvent is one or more of pyridine, dimethyl sulfone, dimethylformamide, dioxane, and piperidine, which are also provided by the present invention.

[0010] Preferably, in step S2, the organic alkali solvent is a pyridine solvent with a mass concentration of 90%.

[0011] Preferably, in step S3, the Citrus aurantium raw material and the organic alkali solvent are placed in an extraction tank with a stirring function for extraction at room temperature, the stirring time is 3-5 hours, the extraction times are three times, the filtrate collected in the first two times is used to collect hesperidin, and the filtrate collected in the third time is used as the organic alkali solvent for the first extraction in the next batch.

[0012] Preferably, in step S4, the filtrate is placed in a concentration kettle to recover the extract under negative pressure conditions, the amount of clean water added is 3-5 times the amount of the extract, and the crystallization time is 3-5 hours.

[0013] Preferably, in step S6, the refining of the aqueous hesperidin crude product comprises the following steps: adding a refining solvent into a refining kettle, stirring, then adding the aqueous hesperidin crude product, when the liquid in the refining kettle is in a suspension, adding a sodium hydroxide solution until the aqueous hesperidin crude product is completely dissolved, adding diatomaceous earth to obtain a dissolving solution, filtering and washing the dissolving solution, collecting the filtrate, adding glacial acetic acid to the filtrate to neutralize the solution to a pH value of 5-9, crystallizing, filtering the precipitated crystals, washing with water, and drying to obtain the hesperidin product.

[0014] Preferably, the amount of the refining solvent is 8-15 times the mass of the crude hydrous hesperidin, the amount of diatomaceous earth is 5% of the mass of the added Fructus Aurantii Immaturus raw material, and the crystallization time is 3-5 hours.

[0015] Preferably, the refining solvent is an aqueous solution or an ethanol solution with a mass concentration of 60-90%.

[0016] The beneficial effects of the present invention are:

[0017] The present invention uses an organic alkaline solvent to extract hesperidin. The extraction method is physical extraction, which is more environmentally friendly and the organic alkaline solvent can be recycled. There is no need to add a large amount of acid and alkali, which reduces the impact on the environment. At the same time, since the extraction process is mild, the loss of hesperidin due to oxidation or other chemical reactions is avoided, so that the extraction conversion rate of hesperidin is higher, the purity of the product is significantly improved, and ultimately higher economic benefits are achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The present invention is a flowchart of a method for extracting hesperidin according to an embodiment of the present invention. DETAILED DESCRIPTION

[0019] The present invention is further described below in conjunction with examples, but it is not intended to limit the scope of the present invention, and is only illustrative. It should be noted that, in the absence of conflict, the embodiments in this application and the technical features in the embodiments can be combined with each other. It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meanings as those of ordinary skill in the art to which this application belongs. The experimental methods used in the following examples are conventional methods unless otherwise specified. Materials, reagents, etc. used in the following examples, unless otherwise specified, can all be obtained from commercial sources.

[0020] The raw material of Citrus aurantium used in the following examples was produced in Meishan, Sichuan, the variety was Citrus aurantium, and the hesperidin content was 26.5%.

[0021] Example 1

[0022] A hesperidin, which is extracted by the following steps:

[0023] (1) Raw material crushing: 500 kg of Citrus aurantium raw material was put into a crusher and crushed into a fineness of 100 mesh.

[0024] (2) Solvent preparation: Prepare pyridine with a mass concentration of 80% as the solvent.

[0025] (3) Extraction: The extraction device uses an extraction tank with a stirring function; in the first extraction, 2500L of solvent is pumped into the extraction tank, stirring is started, and then the crushed Citrus aurantium raw material is added, stirred at room temperature for 5 hours, and filtrate A is collected by filtration; in the second extraction, 2000L of solvent is pumped into the extraction tank, stirring is started, stirred at room temperature for 4 hours, and filtrate B is collected by filtration; in the third extraction, 2000L of solvent is pumped into the extraction tank, stirring is started, stirred at room temperature for 4 hours, and filtrate C is collected by filtration. A total of three extractions were performed, and the filtrate A and filtrate B collected in the first two extractions were used to collect hesperidin, and the filtrate C collected in the third extraction was used as the solvent for the first extraction in the next batch.

[0026] (4) Solvent recovery and crystallization: The filtrate A and the filtrate B are subjected to solvent recovery treatment in a concentration kettle under negative pressure conditions, and the recovered solvent is directly used as the extraction solvent for the next batch; the extract in the concentration kettle is added with 2500 L of clean water to stir and crystallize, and the crystallization time is 3 hours to obtain a crystal liquid.

[0027] (5) Collecting crude product: The crystallized liquid was filtered through a plate and frame filter and washed with clean water to obtain a total of 320 kg of crude hydrous hesperidin.

[0028] (6) Water refining: Add 2500 L of clean water into the refining kettle, start stirring and add the crude hydrous hesperidin. When the liquid in the refining kettle is in a suspension, slowly add sodium hydroxide solution until the crude hydrous hesperidin is completely dissolved. Then add 25 kg of diatomaceous earth to obtain a solution. The solution is filtered and washed, and the filtrate is placed in a crystallization kettle. Glacial acetic acid is added to the crystallization kettle to neutralize the solution to a pH value of 7.5. Crystallize for 3 hours, filter, wash with water, and dry to obtain 126.8 kg of hesperidin product.

[0029] Example 2

[0030] A hesperidin, which is extracted by the following steps:

[0031] (1) Crushing of raw material of Citrus aurantium: 500 kg of raw material of Citrus aurantium was put into a crusher and crushed into a fineness of 100 mesh.

[0032] (2) Solvent preparation: Prepare pyridine with a mass concentration of 70% as the solvent.

[0033] (3) Extraction: The extraction device uses an extraction tank with a stirring function; in the first extraction, 2500L of solvent is pumped into the extraction tank, stirring is started, and then the crushed Citrus aurantium raw material is added, stirred at room temperature for 5 hours, and filtrate A is collected by filtration; in the second extraction, 2500L of solvent is pumped into the extraction tank, stirring is started, stirred at room temperature for 4 hours, and filtrate B is collected by filtration; in the third extraction, 2500L of solvent is pumped into the extraction tank, stirring is started, stirred at room temperature for 4 hours, and filtrate C is collected by filtration. A total of three extractions were performed, and the filtrate A and filtrate B collected in the first two extractions were used to collect hesperidin, and the filtrate C collected in the third extraction was used as the solvent for the first extraction in the next batch.

[0034] (4) Solvent recovery and crystallization: The filtrate A and the filtrate B are subjected to solvent recovery treatment in a concentration kettle under negative pressure conditions, and the recovered solvent is directly used as the extraction solvent for the next batch; the extract in the concentration kettle is added with 2500 L of clean water to stir and crystallize, and the crystallization time is 3 hours to obtain a crystal liquid.

[0035] (5) Collecting crude product: The crystallized liquid was filtered through a plate and frame filter and washed with clean water to obtain 345 kg of crude hydrous hesperidin.

[0036] (6) Alcohol refining: Add 3000 L of 70% ethanol solution into the refining kettle, start stirring and add the crude hydrous hesperidin. When the liquid in the refining kettle is in a suspension, slowly add sodium hydroxide solution until the crude hydrous hesperidin is completely dissolved, then add 25 kg of diatomaceous earth to obtain a solution, filter and wash the solution, and put the filtrate into a crystallization kettle. Add glacial acetic acid to the crystallization kettle to neutralize the solution to a pH of 7. Crystallize for 3 hours, filter, wash with water, and dry to obtain 126.5 kg of hesperidin product.

[0037] Example 3

[0038] The difference from Example 2 is that step (6) adopts water refining, and 3000 L of clean water is added to the refining kettle to obtain 339 kg of crude aqueous hesperidin and 127.2 kg of hesperidin product.

[0039] Example 4

[0040] A hesperidin, which is extracted by the following steps:

[0041] (1) Crushing of raw material of Citrus aurantium: 500 kg of raw material of Citrus aurantium was put into a crusher and crushed into a fineness of 100 mesh.

[0042] (2) Solvent preparation: Prepare pyridine with a mass concentration of 90% as the solvent.

[0043] (3) Extraction: The extraction device uses an extraction tank with a stirring function; in the first extraction, 2500L of solvent is pumped into the extraction tank, stirring is started, and then the crushed Citrus aurantium raw material is added, stirred at room temperature for 5 hours, and filtrate A is collected by filtration; in the second extraction, 2000L of solvent is pumped into the extraction tank, stirring is started, stirred at room temperature for 4 hours, and filtrate B is collected by filtration; in the third extraction, 2000L of solvent is pumped into the extraction tank, stirring is started, stirred at room temperature for 4 hours, and filtrate C is collected by filtration. A total of three extractions were performed, and the filtrate A and filtrate B collected in the first two extractions were used to collect hesperidin, and the filtrate C collected in the third extraction was used as the solvent for the first extraction in the next batch.

[0044] (4) Solvent recovery and crystallization: The filtrate A and the filtrate B are subjected to solvent recovery treatment in a concentration kettle under negative pressure conditions, and the recovered solvent is directly used as the extraction solvent for the next batch; the extract in the concentration kettle is added with 2500 L of clean water to stir and crystallize, and the crystallization time is 3 hours to obtain a crystal liquid.

[0045] (5) Collecting crude product: The crystallized liquid was filtered through a plate and frame filter and washed with clean water to obtain 305 kg of crude hydrous hesperidin.

[0046] (6) Water refining: Add 2500 L of clean water into the refining kettle, start stirring and add the crude hydrous hesperidin. When the liquid in the refining kettle is in a suspension, slowly add sodium hydroxide solution until the crude hydrous hesperidin is completely dissolved. Then add 25 kg of diatomaceous earth to obtain a solution. The solution is filtered and washed, and the filtrate is placed in a crystallization kettle. Glacial acetic acid is added to the crystallization kettle to neutralize the solution to a pH value of 8.0. Crystallize for 3 hours, filter, wash with water, and dry to obtain 127.1 kg of hesperidin product.

[0047] Example 5

[0048] Different from Example 1, in step (2) of this example, dioxane is used as the solvent, 303 kg of crude aqueous hesperidin is obtained in step (5), and 122.7 kg of hesperidin product is obtained in step (6).

[0049] Example 6

[0050] Different from Example 1, dimethylformamide is used as solvent in step (2) of this example, 318 kg of crude aqueous hesperidin is obtained in step (5), and 122.4 kg of hesperidin product is obtained in step (6).

[0051] Example 7

[0052] Different from Example 1, in step (2) of this example, dimethyl sulfone is used as the solvent, 315 kg of crude aqueous hesperidin is obtained in step (5), and 123.2 kg of hesperidin product is obtained in step (6).

[0053] Example 8

[0054] Different from Example 1, piperidine is used as the solvent in step (2) of this example, 311 kg of crude aqueous hesperidin is obtained in step (5), and 122.2 kg of hesperidin product is obtained in step (6).

[0055] Comparative Example 1

[0056] A hesperidin, which is extracted by the following steps:

[0057] (1) Crushing of raw material of Citrus aurantium: 500 kg of raw material of Citrus aurantium was put into a crusher and crushed into a fineness of 100 mesh.

[0058] (2) Solvent preparation: Prepare 15000 L of 0.1 M sodium hydroxide solution.

[0059] (3) Extraction: The extraction equipment uses an extraction tank for continuous percolation extraction; during the first extraction, the raw material of Citrus aurantium is put into the extraction tank, and then the extraction solvent is pumped into the extraction tank, and percolation is performed at a flow rate of 1000 L / h. The percolation cycle is 16 hours. The percolation liquid is filtered to obtain a clarified filtrate, and the filtrate is pumped into a crystallization tank, and dilute sulfuric acid is added to neutralize and crystallize. The crystallization time is 3 hours;

[0060] (4) Collecting crude product: filtering the crystal solution through a plate and frame filter and washing with clean water to obtain 255 kg of crude hydrous hesperidin;

[0061] (5) Water refining: Refining in a refining kettle: first add 2500 L of clean water into the refining kettle, start stirring and add the crude hydrous hesperidin. When the liquid in the refining kettle is in a suspension, slowly add sodium hydroxide solution until the crude hydrous hesperidin is completely dissolved. Then add 25 kg of diatomaceous earth. The dissolved liquid is filtered through a filter, washed with clean water, and the filtrate is combined and added to a crystallization kettle. Glacial acetic acid is added to neutralize the solution to a pH value of 8.0. Crystallize for 3 hours, filter, wash with water, and dry to obtain 106.3 kg of hesperidin product.

[0062] The hesperidin finished products in Examples 1-8 and Comparative Example 1 were tested for content. The content testing method was based on the method for measuring the content of hesperidin by HPLC in the Chinese Pharmacopoeia (Volume 1) (2005), and the yield, content and purity of hesperidin were calculated. The test results are shown in Table 1.

[0063] Table 1: Quality test results of the hesperidin products in Examples 1-8 and Comparative Example 1

[0064] project Product volume Yield content purity Example 1 126.8kg 25.36％ 94.5％ 95.9％ Example 2 126.5kg 25.3％ 96.2％ 96.9％ Example 3 127.2kg 25.44％ 93.47％ 94.8％ Example 4 127.1kg 25.42％ 94.8％ 96.2％ Example 5 122.7kg 24.54％ 93.4％ 94.8％ Example 6 122.4kg 24.48％ 93.8％ 94.6％ Example 7 123.2kg 24.64％ 93.5％ 95.1％ Example 8 122.2kg 24.44％ 93.2％ 94.7％ Comparative Example 1 106.3kg 21.26％ 91.5％ 93.1％

[0065] According to the measurement results in Table 1, it can be seen from the data obtained from the extraction processes of Examples 1-8 that the quality and yield of the products extracted and refined using organic alkaline solvents are very stable, and the yield and product quality are significantly higher than the chemical extraction technology used in Comparative Example 1, which fully demonstrates that physical extraction technology is superior to chemical extraction technology; at the same time, it can be seen from the data obtained from the extraction processes of Examples 1 and Examples 5-8 that different organic alkaline solvents such as pyridine, dimethyl sulfoxide, dimethylformamide and dioxane are used to extract hesperidin respectively, and the product amount and yield of the pyridine extraction process are significantly higher than those of other solvents.

[0066] In summary, the method for extracting hesperidin of the present invention has an extraction temperature of room temperature, an organic alkali solvent extraction method, which is a physical extraction, and the extraction process has no loss to hesperidin. The organic alkali can be recycled and reused, reducing water consumption, and the hesperidin extraction conversion rate can reach more than 95%.

[0067] Economic value: From the above extraction, we know that according to the organic alkali solvent extraction process parameters, the costs of solvent auxiliary materials, energy consumption, etc. used for 1000kg of Citrus aurantium raw material are 2500 yuan higher than the chemical extraction costs. However, the organic alkali solvent extraction can produce more than 40 kg of hesperidin products per ton of Citrus aurantium raw material. The current market price of this quality flavonoid product is 120-150 yuan / kg. Each ton of Citrus aurantium raw material can produce products worth 5000-6000 yuan. Each ton of Citrus aurantium raw material saves 2500-3500 yuan in costs compared with the original production. If the factory purchases 1000 tons of Citrus aurantium raw material a year, it can increase profits by 2.5-3.5 million yuan.

[0068] The above description is only a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as a preferred embodiment as above, it is not intended to limit the present invention. Any technician familiar with the profession can make some changes or modifications to equivalent embodiments of equivalent changes using the technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the scope of the technical solution of the present invention.

Claims

1. A novel method for extracting hesperidin, characterized in that: The following steps are involved: S1, crushing the raw material of Citrus aurantium; S2, preparing an organic base solvent with a mass concentration of 60-90%; S3, mixing the Fructus Aurantii Immaturus raw material and the organic base solvent, stirring, and filtering to collect the filtrate; S4, recovering the organic alkali solvent from the filtrate under negative pressure, using the recovered solvent as the extraction solvent for the next batch to obtain an extract, adding clean water to the extract for stirring and crystallization to obtain a crystal liquid; S5, filtering the crystallization liquid and washing with water to obtain a crude hydrous hesperidin product; S6, refining the crude aqueous hesperidin to obtain a hesperidin product.

2. The novel method for extracting hesperidin according to claim 1, characterized in that: In step S1, the Fructus Aurantii Immaturus raw material is put into a crusher and crushed to a fineness of 80-120 meshes.

3. The novel method for extracting hesperidin according to claim 1, characterized in that: In step S2, the total volume of the organic base solvent used is 15-25 times the mass of the Fructus Aurantii Immaturus raw material.

4. The novel method for extracting hesperidin according to claim 1, characterized in that: In step S2, the organic alkaline solvent is one or more of pyridine, dimethyl sulfone, dimethylformamide, dioxane, and piperidine.

5. The novel method for extracting hesperidin according to claim 1, characterized in that: In step S2, the organic alkali solvent is a pyridine solvent with a mass concentration of 90%.

6. The novel method for extracting hesperidin according to claim 1, characterized in that: In step S3, the Citrus aurantium raw material and the organic alkali solvent are placed in an extraction tank with a stirring function for extraction at room temperature. The stirring time is 3-5 hours and the extraction times are three times. The filtrates collected in the first two times are used to collect hesperidin, and the filtrate collected in the third time is used as the organic alkali solvent for the first extraction in the next batch.

7. The novel method for extracting hesperidin according to claim 1, characterized in that: In step S4, the filtrate is placed in a concentration kettle to recover the extract under negative pressure conditions, the amount of clean water added is 3-5 times the amount of the extract, and the crystallization time is 3-5 hours.

8. The novel method for extracting hesperidin according to claim 1, characterized in that: In step S6, the refining of the aqueous hesperidin crude product includes the following steps: adding a refining solvent into a refining kettle, stirring, then adding the aqueous hesperidin crude product, when the liquid in the refining kettle is in a suspension, adding a sodium hydroxide solution until the aqueous hesperidin crude product is completely dissolved, adding diatomaceous earth to obtain a dissolving solution, filtering and washing the dissolving solution, collecting the filtrate, adding glacial acetic acid to the filtrate to neutralize the solution to a pH value of 5-9, crystallizing, filtering the precipitated crystals, washing with water, and drying to obtain the hesperidin product.

9. The novel method for extracting hesperidin according to claim 8, characterized in that: The amount of the refining solvent is 8-15 times the mass of the crude hydrous hesperidin, the amount of diatomaceous earth is 5% of the mass of the added Citrus aurantium raw material, and the crystallization time is 3-5 hours.

10. The novel method for extracting hesperidin according to claim 8 or 9, characterized in that: The refining solvent is an aqueous solution or an ethanol solution with a mass concentration of 60-90%.

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