Method for extracting and purifying curcumine in curcuma oil resin

Abstract

The invention relates to the technical field of extraction of effective active ingredients of plants, and provides a method for extracting and purifying curcumine in curcuma oil resin, which is characterized in that a mixing adsorption-elution-crystallization integrated process is adopted, and an adsorption material and a solvent system are optimized to realize process simplification and resource circulation. The method comprises the following steps: dissolving curcuma oil resin, adding one or more adsorption materials for adsorption extraction, eluting with a first solvent, and filtering and concentrating the eluent to obtain an extract; and adding a second solvent into the extract, heating, dissolving, adding into a crystallizing tank, adding a certain proportion of seed crystal, crystallizing, and centrifugally drying to obtain the curcumin. The purity of the obtained curcumin is greater than 95%; a single solvent system is used for replacing a traditional mixed solvent, the technological process is simplified, the solvent recovery efficiency is improved, the production cost is reduced, the adsorption material can be reused after being treated, and resource waste is further reduced.

Description

Technical Field

[0001] This invention belongs to the field of plant active ingredient extraction technology, and particularly relates to a method for extracting and purifying curcumin from ginger oil resin. Background Technology

[0002] Curcumin is a class of polyphenolic compounds, with its main components being curcumin, demethoxycurcumin, and didemethoxycurcumin. Due to its significant antioxidant activity and natural coloring properties, curcumin has become one of the core products in the field of plant extracts, and is widely used in various industrial sectors such as health products, beverages, and cosmetics.

[0003] In industrial production, curcumin extraction typically employs an ethanol reflux process, which generates a large amount of reddish-brown, viscous turmeric oil resin as a byproduct. Traditionally, this byproduct is often discarded or disposed of at extremely low prices, leading to resource waste and potential environmental pollution risks from residual organic solvents (such as ethanol). Studies have shown that this byproduct retains a certain amount of curcumin and some fat-soluble active ingredients. If extraction and purification can be achieved, the comprehensive utilization rate of the raw material will be significantly improved. However, current industry treatment of turmeric oil resin still faces the following technical challenges: traditional column chromatography requires a mixed solvent system, resulting in complex processes and difficulties in solvent recovery; and disposable silica gel media are often used, without considering their regeneration. Therefore, developing a simple and efficient curcumin extraction method is a key breakthrough in solving the resource utilization problem of curcumin byproduct—turmeric oil resin—and is of great significance for promoting the transformation of the plant extraction industry towards green manufacturing. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a method for extracting and purifying curcumin from turmeric oil resin, aiming to solve the problems mentioned in the background art.

[0005] This invention provides a method for extracting and purifying curcumin from turmeric oil resin. After the turmeric oil resin is dissolved, one or more adsorbent materials are added for adsorption extraction. The resin is eluted with a first solvent, and the eluent is filtered and concentrated to obtain an extract. A second solvent is added to the extract and heated to dissolve it. The extract is then added to a crystallization tank, and a certain proportion of seed crystals are added for crystallization. After centrifugation and drying, curcumin is obtained.

[0006] Furthermore, the adsorbent material is selected from one or more of the following materials: silica gel with a particle size of 100–400 mesh; alumina with a particle size of 100–200 mesh; macroporous adsorption resin with a particle size of 450–600 μm; and polyamide with a particle size of 80–200 mesh.

[0007] Further, after the ginger oil resin is dissolved, an adsorbent is added to obtain a ginger oil resin mixture, wherein the adsorbent ratio to ginger oil resin is 5-15:1 by mass.

[0008] Furthermore, the mixture of ginger oil and resin is: first solvent = 1 kg : 8-15 L.

[0009] Furthermore, the first solvent is any one of n-hexane, acetone, dichloromethane, or ethyl acetate, and the extraction method is intermittent extraction, with an extraction time of 4-6 hours.

[0010] Furthermore, the second organic solvent is any one of acetone, ethyl acetate, n-butanol, petroleum ether, dichloromethane, or acetonitrile.

[0011] Furthermore, the ratio of extract to second solvent is 1 kg to 1-3 L.

[0012] Furthermore, the seed crystals are extracted and purified curcumin, and the mass of the added seed crystals is 1-10% of the mass of the extract.

[0013] Furthermore, after obtaining curcumin, the process also includes: adding a third organic solvent to the waste adsorbent material for treatment, filtering and drying to obtain regenerated adsorbent material; the third organic solvent includes any one or more of ethanol, acetone, dichloromethane, methanol or chloroform, and the soaking time is 4-6 hours.

[0014] The present invention has the following technical effects: (1) By directly adding adsorbent material to turmeric oil resin for mixed adsorption, the shortcomings of traditional column chromatography technology, such as cumbersome process and long time consumption, are effectively overcome. This process involves uniformly mixing turmeric oil resin with media such as silica gel and macroporous adsorption resin, so that the target component is enriched at the solid-liquid interface. Then, a single solvent is used for direct elution and crystallization to complete the purification process, and the purity of the obtained curcumin is greater than 95%. This process avoids the complex ratio and recovery problems of multi-stage solvent systems in traditional methods, significantly shortens the preparation cycle, and is more suitable for large-scale industrial production.

[0015] (2) By adjusting the combination of adsorbent materials with different polarity characteristics and optimizing the elution solvent, curcumin-like target components can be selectively and preferentially adsorbed. Using a single solvent system instead of traditional mixed solvents greatly simplifies the solvent recovery process and reduces production costs. At the same time, the silica gel, macroporous adsorption resin and other media used can be recycled after simple regeneration treatment, further reducing raw material consumption and waste generation.

[0016] (3) During the process, the main chemical components of curcumin do not undergo structural changes, but due to the differences in selective adsorption of each component by different media, their relative content ratio will be adaptively adjusted. This characteristic can be used to precisely control the composition of the final product. Attached Figure Description

[0017] Exemplary embodiments of the present invention can be more fully understood by referring to the following figures: Figure 1 This is a liquid chromatogram of curcumin in the turmeric oil resin of Example 1 of the present invention.

[0018] Figure 2 This is a liquid chromatogram of curcumin in the turmeric extract of Example 1 of the present invention.

[0019] Figure 3 This is a liquid chromatogram of curcumin extracted in Example 1 of the present invention.

[0020] Figure 4 This is a liquid chromatogram of curcumin in the regenerated adsorption material of Example 1 of the present invention.

[0021] Figure 5 This is the liquid chromatogram of curcumin extracted in Example 3 of the present invention. Detailed Implementation

[0022] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention.

[0024] This invention provides a method for extracting and purifying curcumin from turmeric oil resin. After the turmeric oil resin is dissolved, one or more adsorbent materials are added for adsorption extraction. The resin is eluted with a first solvent, and the eluent is filtered, concentrated, and an extract is obtained. A second solvent is added to the extract and heated to dissolve it. The extract is then added to a crystallization tank, and a certain proportion of seed crystals are added for crystallization. After centrifugation and drying, curcumin is obtained.

[0025] In some embodiments, the adsorbent material is selected from one or more of the following materials: silica gel with a particle size of 100–400 mesh; alumina with a particle size of 100–200 mesh; macroporous adsorption resin with a particle size of 450–600 μm; and polyamide with a particle size of 80–200 mesh.

[0026] In some embodiments, after the ginger oil resin is dissolved, an adsorbent material is added to obtain a ginger oil resin mixture, wherein the adsorbent material: ginger oil resin = 5-15:1 by mass ratio.

[0027] In some embodiments, the ratio of ginger oil resin mixture to first solvent is 1 kg to 8-15 L.

[0028] In some embodiments, the first solvent is any one of n-hexane, acetone, dichloromethane, or ethyl acetate, and the extraction method is intermittent extraction with an extraction time of 4-6 hours.

[0029] In some embodiments, the second organic solvent is any one of acetone, ethyl acetate, n-butanol, petroleum ether, dichloromethane, and acetonitrile.

[0030] In some embodiments, the ratio of extract to second solvent is 1 kg to 1-3 L.

[0031] In some embodiments, the seed crystals are extracted and purified curcumin, and the mass of the seed crystals added is 1-10% of the mass of the extract.

[0032] In some embodiments, after obtaining curcumin, the method further includes: adding a third organic solvent to the waste adsorbent material for treatment, filtering and drying to obtain regenerated adsorbent material; the third organic solvent includes any one or more of ethanol, acetone, dichloromethane, methanol or chloroform, and the soaking time is 4-6 hours.

[0033] Example 1 10 kg of turmeric oil resin was dissolved and mixed with 50 kg of silica gel (100 mesh). 200 L of ethyl acetate was added for extraction, using an intermittent extraction method for 4 hours. The extract was filtered and concentrated to obtain 2.54 kg of extract. 2.54 L of acetone was added to dissolve the extract and then added to a crystallization tank. 0.025 kg of curcumin crystals were added to the crystallization tank. After centrifugation and drying, 0.56 kg of curcumin with a purity of 97.5% was obtained.

[0034] Methanol was added to the waste silica gel after use, and the mixture was sonicated for 30 minutes and soaked for 4 hours. After filtration and drying, recycled silica gel was obtained.

[0035] The liquid chromatogram of curcumin in turmeric oil resin is shown below. Figure 1 As shown; the liquid chromatogram of curcumin in turmeric extract is as follows. Figure 2 As shown; the liquid chromatogram of the extracted curcumin is as follows. Figure 3 As shown; the liquid chromatogram of curcumin in regenerated silica gel is as follows. Figure 4 As shown.

[0036] Example 2 10 kg of turmeric oil resin was added to 70 kg of mixed adsorbent material (200 mesh silica gel: 450 μm macroporous adsorbent resin = 2:1) and mixed thoroughly. 220 L of dichloromethane was added for extraction, using an intermittent extraction method for 6 hours. The extract was filtered and concentrated to obtain 2.84 kg of turmeric extract. 5.68 L of ethyl acetate, a crystallization solvent, was added to the extract to dissolve it, and the mixture was then transferred to a crystallization tank. 0.086 kg of curcumin crystals were added to the crystallization tank, and after centrifugation and drying, 0.78 kg of curcumin was obtained with a purity of 96.3%.

[0037] Ethanol was added to the used waste mixed adsorbent material, followed by ultrasonication for 30 minutes and soaking for 6 hours. The material was then filtered and dried to obtain regenerated mixed adsorbent material.

[0038] Example 3 10 kg of turmeric oil resin was dissolved and then mixed with 60 kg of regenerated macroporous adsorption resin (600 μm). 200 L of methanol was added for extraction, using an intermittent extraction method for 5 h. The extract was filtered and concentrated to obtain 2.43 kg of turmeric extract. 2.43 L of ethyl acetate was added to the extract to dissolve it, and the mixture was then added to a crystallization tank. 0.024 kg of curcumin crystals were added to the crystallization tank, and after centrifugation and drying, 0.63 kg of curcumin was obtained with a purity of 95.8%.

[0039] Ethanol was added to the used waste macroporous adsorption resin, and the mixture was sonicated for 30 minutes and soaked for 4 hours. The resin was then filtered and dried to obtain regenerated macroporous adsorption resin.

[0040] The chromatogram of the extracted curcumin liquid chromatography is shown below. Figure 5 As shown.

[0041] Comparative Example 1 10 kg of turmeric oil resin was dissolved and mixed with 50 kg of silica gel (200 mesh). 260 L of ethanol was added for extraction. The extract was filtered and concentrated to obtain 0.78 kg of turmeric extract. 1.56 L of acetone was added to the extract for crystallization and then added to a crystallization tank. 0.0078 kg of curcumin was added to the crystallization tank for crystallization. After centrifugation and drying, 0.13 kg of curcumin was obtained with a purity of 47.5%.

[0042] Ethanol was added to the used waste silica gel, and the mixture was sonicated for 30 minutes and soaked for 4 hours. The mixture was then filtered and dried to obtain recycled silica gel.

[0043] Comparative Example 2 10 kg of turmeric oil resin was dissolved and then mixed with 80 kg of polyamide (100 mesh). 200 L of ethyl acetate was added for extraction. The extract was filtered and concentrated to obtain 1.76 kg of turmeric extract. 1.76 L of acetone was added to the extract and heated to dissolve it. After dissolution, the extract was transferred to a crystallization tank without adding any crystals. After centrifugation and drying, 0.23 kg of curcumin was obtained with a purity of 67.5%.

[0044] Ethanol was added to the waste polyamide after use, followed by ultrasonication for 30 minutes and soaking for 6 hours. The mixture was then filtered and dried to obtain recycled polyamide.

[0045] Based on embodiments 1-3, the present invention has been modified to form more embodiments, as shown in Table 1.

[0046] Table 1. Results of curcumin purification under different treatments

[0047] This process involves uniformly mixing turmeric oil resin with media such as silica gel and macroporous adsorption resin. By selecting a suitable combination of adsorbent and elution solvent, target products such as curcumin are enriched at the solid-liquid interface. The adsorbent uses one or more of the following: silica gel, alumina, macroporous adsorption resin, and polyamide. The elution solvent is typically one of the following: n-hexane, acetone, dichloromethane, or ethyl acetate. After elution, a suitable solvent is selected for crystallization. Adding seed crystals helps improve the yield and purity; the purity of the obtained curcumin is greater than 95%.

[0048] Furthermore, the extraction and purification process mainly relies on physical adsorption and desorption. The main chemical components of curcumin, such as curcumin, demethoxycurcumin, and didemethoxycurcumin, do not undergo structural changes. However, due to the differences in selective adsorption of each component by different media, their relative content ratios will be adaptively adjusted. This characteristic can also be used to precisely control the composition of the final product.

[0049] In summary, the core of this invention lies in the adoption of an integrated process of mixing, adsorption, elution, and crystallization. By optimizing the adsorption material and solvent system, the process is simplified and resources are recycled. The purity of the obtained curcumin is greater than 95%. By replacing the traditional mixed solvent with a single solvent system, the process flow is simplified, the solvent recovery efficiency is improved, and the production cost is reduced. The adsorption material can be reused after treatment, further reducing resource waste.

[0050] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for extracting and purifying curcumin from ginger oil resin, characterized in that: After the turmeric oil resin is dissolved, one or more adsorbent materials are added for adsorption extraction. The mixture is eluted with a first solvent, and the eluent is filtered, concentrated, and a paste is obtained. A second solvent is added to the paste and heated to dissolve it. The paste is then added to a crystallization tank, and a certain proportion of seed crystals are added for crystallization. After centrifugation and drying, curcumin is obtained.

2. The method as described in claim 1, characterized in that: The adsorbent is selected from one or more of the following materials: silica gel with a particle size of 100–400 mesh; alumina with a particle size of 100–200 mesh; macroporous adsorption resin with a particle size of 450–600 μm; Polyamide, with a particle size of 80–200 mesh.

3. The method as described in claim 2, characterized in that: After dissolving the ginger oil resin, an adsorbent material is added to obtain a ginger oil resin mixture, wherein the adsorbent material: ginger oil resin = 5-15:1 by mass ratio.

4. The method as described in claim 3, characterized in that: Ginger oil resin mixture: First solvent = 1kg: 8-15L.

5. The method as described in claim 1, characterized in that: The first solvent is any one of hexane, acetone, dichloromethane, or ethyl acetate. The extraction method is intermittent extraction, and the extraction time is 4-6 hours.

6. The method as described in claim 1, characterized in that: The second organic solvent is any one of acetone, ethyl acetate, n-butanol, petroleum ether, dichloromethane, or acetonitrile.

7. The method as described in claim 6, characterized in that: Extract: Second solvent = 1kg: 1-3L.

8. The method as described in claim 1, characterized in that: The seed crystals are extracted and purified curcumin, and the mass of the seed crystals added is 1-10% of the mass of the extract.

9. The method as described in claim 1, characterized in that: After obtaining curcumin, the process also includes: adding a third organic solvent to the waste adsorbent material for treatment, filtering and drying to obtain regenerated adsorbent material; the third organic solvent includes any one or more of ethanol, acetone, dichloromethane, methanol or chloroform, and the soaking time is 4-6 hours.

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