A method for obtaining curcumin and its application

Abstract

The present invention relates to the technical field of plant component extraction, and specifically discloses a method for obtaining curcumin and its application. The method for obtaining curcumin of the present invention comprises: using ethyl acetate extract of turmeric as raw material, and fully mixing the raw material with aqueous enzyme solution; the volume ratio of ethyl acetate in the raw material is 50-80%. The present invention has the advantages of simple operation, simple process, short processing time and less wastewater generation, is suitable for scaled-up production application, and can also improve the yield of curcumin and generate more value-added income.

Description

Technical Field

[0001] The invention relates to the technical field of plant component extraction, in particular to a method for obtaining curcumin and application thereof. Background Art

[0002] As one of the natural pigments, curcumin has antibacterial, anti-inflammatory, anti-tumor, choleretic, antioxidant, lipid-lowering, and anti-atherosclerotic effects, and is therefore widely used in the fields of food and medicine. The traditional curcumin extraction process includes relatively mature methods such as solvent extraction, acid-base extraction, and sodium salicylate, but the solvent extraction method is still more suitable for industrial production. The optimization of the solvent recovery process on the production line can reduce solvent loss, which can reduce production costs and improve economic benefits. With the improvement of scientific and technological levels, the enzyme method has also become a means of extracting natural active ingredients from plants. Its main purpose is to use the biological activity of enzymes to destroy the cell walls of plants and release more active ingredients, thereby achieving the effect of improving the extraction rate.

[0003] Chinese patent CN105061168A adds a composite enzyme composed of cellulase, amylase and papain to the turmeric slurry prepared from turmeric powder and water. Cellulase can improve the dissolution of active ingredients, and amylase and papain can decompose and affect refined starch and protein, thereby improving the yield of curcumin. Chinese patent CN106810432A also uses turmeric as raw material to prepare slurry, uses microwave extraction and amylase fermentation methods to improve the extraction yield, and improves the problems of low extraction rate, waste of resources and environmental pollution in existing turmeric production. Chinese patent CN113387785A uses a composite enzyme of cellulase, hemicellulase, pectinase and amylase to enzymolyze turmeric slurry, adds surfactants such as Tween 80 to the extraction solvent, and realizes high extraction yield by ultrasound-assisted extraction. The above patents all start from preparing turmeric slurry from turmeric powder, and use multiple enzyme enzymolysis and new extraction methods to achieve the purpose of improving the yield of curcumin. However, in actual production, turmeric slurry needs to add 3-6 or 1.5-4 parts of water of turmeric powder, which will produce a large amount of wastewater in production, which is not conducive to industrial production. In Chinese patent CN105061168A, 7-9 parts of ethanol solution of enzymolysis solution are added, which easily causes a large amount of solvent loss, and the recovery of ethanol requires more energy consumption, which is not suitable for production conversion. Moreover, the existing extraction and processing technology is relatively mature, and the curcumin extraction yield is relatively high. Applying the existing enzymatic method to the enzymolysis of raw materials to improve the extraction yield will increase the production cost, which is not conducive to practical application.

[0004] Therefore, it is necessary to study how to give full play to the advantages of the enzymatic method and apply it to the production process to achieve the effect of increasing the yield of curcumin and give full play to the advantages of low cost, simple operation and economic feasibility. Summary of the invention

[0005] One of the purposes of the present invention is to provide a process for improving the yield of curcumin obtained by enzymatic method and reducing the production cost.

[0006] In order to achieve this object, the technical solution of the present invention is as follows:

[0007] The invention provides a method for obtaining curcumin, which comprises: taking ethyl acetate extract of turmeric as raw material, and fully mixing the raw material with aqueous enzyme solution; the volume proportion of ethyl acetate in the raw material is 50-80%.

[0008] The method of the invention comprises the steps of mixing the raw material with an aqueous enzyme solution, stirring the mixture sufficiently for reaction and then standing the mixture to separate the turmeric enzymolysis solution and an aqueous solution, and subjecting the turmeric enzymolysis solution to reduced pressure concentration, crystallization, filtration and drying to obtain a curcumin product.

[0009] In the scheme of curcumin production by enzymatic method at present, in order to make water enzyme liquid and raw material fully react, turmeric solid powder or its aqueous solution are mostly adopted as enzymolysis raw material, but the present invention has found that when this mode is applied to the industrialized production of curcumin, production cost is higher, for this reason the present invention has studied the enzymolysis object especially, find that when the enzymolysis raw material is changed into the ethyl acetate extract of turmeric using specific concentration, can be during enzymolysis, by stirring, raw material and water enzyme liquid can be fully contacted, realize sufficient enzymolysis and decontamination (removing the impurity that affects the crystallization of curcumin, to improve yield), and after stopping stirring, only need to naturally stand this reaction system and can realize liquid-liquid separation rapidly, obtain the turmeric enzymolysis liquid (upper strata) and aqueous solution (lower floor) after enzymolysis. This mode is easy to operate, and curcumin yield is high, and cost is low, is beneficial to industrialized production.

[0010] It is generally believed that most enzymes are soluble in water but insoluble in almost all organic solvents. Diffusion restriction will occur between enzyme and organic solvent, and it is suspended in solvent, which directly affects the effect of enzymolysis. The present invention has also confirmed that the method that enzyme directly acts on turmeric extract is not feasible during research. For this reason, the present invention has found that the characteristic that water is slightly soluble in ethyl acetate can be utilized, and turmeric ethyl acetate extract is used as enzymolysis object, and water enzyme liquid and ethyl acetate extract are fully mixed, and the dispersity of enzyme in ethyl acetate is increased, and the diffusion restriction of enzyme catalysis is broken, and the enzymolysis is promoted. And in the subsequent separation, water can be quickly layered with ethyl acetate, so that the inventive method not only takes into account the extraction effect of curcumin, but also improves production efficiency.

[0011] The proportion of ethyl acetate in the raw material of the present invention can be obtained by concentrating the conventional ethyl acetate extract of turmeric under reduced pressure. The conditions for concentrating under reduced pressure to obtain the turmeric concentrate can be: vacuum degree -0.07 to -0.08Mpa, temperature 70 to 75°C.

[0012] The specific proportion of ethyl acetate can ensure that the curcumin in the raw material does not crystallize and affect the extraction effect, and can also reduce the total volume of the raw material while ensuring the yield of curcumin, help reduce the amount of subsequent enzyme-containing aqueous solution, and reduce production costs.

[0013] Preferably, the ethyl acetate extract of turmeric is obtained by repeatedly extracting turmeric with ethyl acetate for multiple times, so as to increase the product content.

[0014] The specific process of reduced pressure concentration, crystallization, filtration and drying of the turmeric enzymolyte in the present invention can adopt conventional operations in the art, such as the turmeric enzymolyte can be reduced pressure concentrated at -0.075Mpa and 75°C to obtain turmeric extract, wherein the volume of ethyl acetate accounts for 20-25%, and the extract is stirred and crystallized in a water bath at 25-30°C for 20-24h, and the curcumin is obtained by suction filtration, and the extract is dried in an oven at 80-90°C for 10-15h to obtain the curcumin product.

[0015] In the method of the present invention, the temperature during the fully stirring reaction is 45-55° C., the stirring time is 4-6 h, and the standing time is 2-4 h, preferably 3 h.

[0016] The invention can fully mix the aqueous enzyme solution with the raw material through sufficient stirring to achieve a uniform effect, so as to give full play to the activity of the enzyme and achieve a better enzymolysis effect.

[0017] In the method of the present invention, the enzyme in the aqueous enzyme solution is at least one of cellulase, amylase, protease and pectinase.

[0018] In the method of the present invention, when the raw material is mixed with the aqueous enzyme solution, the dosage of the aqueous enzyme solution is 10-15% of the volume of the raw material; the enzyme content in the aqueous enzyme solution is 0.2-0.4%.

[0019] Preferably, the aqueous enzyme solution of the present invention is a mixture of enzyme and tap water.

[0020] Preferably, in the method of the present invention, the volume proportion of ethyl acetate in the raw material is 60-65%.

[0021] Preferably, in the method of the present invention, the enzyme in the aqueous enzyme solution is a protease.

[0022] When the raw material is mixed with the aqueous enzyme solution, the amount of the aqueous enzyme solution used is 12-13% of the volume of the raw material.

[0023] The temperature of the reaction was 48-52°C during full stirring.

[0024] The present invention also provides an application of the above method in improving the yield of curcumin obtained by enzymatic method and / or reducing the cost of obtaining curcumin by enzymatic method.

[0025] The beneficial effects of the present invention are at least:

[0026] (1) The enzymatic method was used to improve the yield of curcumin. The enzymatic method was applied to the actual production process, which significantly improved the yield of curcumin.

[0027] (2) The turmeric concentrate containing ethyl acetate is used as the enzymatic hydrolysis raw material, and the characteristics of the aqueous enzyme solution being slightly soluble in ethyl acetate are utilized. After enzymatic hydrolysis, the turmeric concentrate and the aqueous enzyme solution can be quickly separated, thereby improving production efficiency.

[0028] (3) The present invention has low cost, simple operation, easy control of reaction conditions, high output curcumin content and stable product quality, can generate more value-added income, and is more suitable for industrial production. DETAILED DESCRIPTION

[0029] The preferred embodiments of the present invention will be described in detail below in conjunction with examples. It should be understood that the following examples are provided only for the purpose of illustration and are not intended to limit the scope of the present invention. Those skilled in the art may make various modifications and substitutions to the present invention without departing from the purpose and spirit of the present invention.

[0030] The experimental methods used in the following examples are conventional methods unless otherwise specified. The materials, reagents, etc. used in the following examples are commercially available or prepared according to conventional methods in the art unless otherwise specified.

[0031] The content of curcumin in the present invention is determined according to the detection method of "United States Pharmacopoeia USP39-Curcumin".

[0032] In the specific implementation mode of the present invention, the preparation method of the ethyl acetate extract of turmeric used is as follows: 1000g of turmeric raw material is taken, crushed (the crushed particle size is 40 mesh with a transmittance of more than 95%, and the transmittance of 20 mesh is 100%), granulated, 3000ml of ethyl acetate is added, stirred in a water bath at 40°C for 1h, filtered to obtain a filter cake and a filtrate, the filter cake is turmeric residue, and the filtrate is turmeric extract, the above conditions are repeated 5 times, and the combined extracts enter the reduced pressure concentration stage, wherein the content of curcumin is 0.54%.

[0033] Example 1

[0034] This embodiment provides a process for increasing the yield of curcumin by enzymatic method, and the steps are as follows:

[0035] Take 2000 ml of ethyl acetate extract of turmeric, concentrate under reduced pressure (-0.075 MPa, 75° C.) to obtain 120 ml of turmeric concentrate, wherein the volume proportion of ethyl acetate is 50%, add 12 ml of aqueous enzyme solution to the turmeric concentrate, wherein the content of protease in the aqueous enzyme solution is 0.2%, stir evenly in a 45° C. water bath for 4 hours, let it stand naturally for 3 hours, and separate the liquid into turmeric hydrolyzate and aqueous solution. The turmeric hydrolyzate is concentrated under reduced pressure at -0.075 MPa, 75° C. to a volume proportion of ethyl acetate of 22%, stir and crystallize in a 25-30° C. water bath for 22 hours, and dry in an oven at 85° C. for 12 hours after suction filtration to obtain a curcumin product.

[0036] Example 2

[0037] This embodiment provides a process for increasing the yield of curcumin by enzymatic method, and the steps are as follows:

[0038] 2000 ml of ethyl acetate extract of turmeric was taken and concentrated under reduced pressure to obtain 300 ml of turmeric concentrate, wherein the volume proportion of ethyl acetate was 80%, 45 ml of aqueous enzyme solution was added to the turmeric concentrate, wherein the content of protease in the aqueous enzyme solution was 0.4%, and the mixture was stirred evenly in a water bath at 55 ° C for 6 hours, and then naturally allowed to stand for 3 hours, and liquid-liquid separation was performed to obtain a turmeric hydrolyzate and an aqueous solution, and the turmeric hydrolyzate was subjected to the same reduced pressure concentration, crystallization, filtration and drying steps as described in Example 1 to obtain a curcumin product.

[0039] Example 3

[0040] This embodiment provides a process for increasing the yield of curcumin by enzymatic method, and the steps are as follows:

[0041] 2000 ml of ethyl acetate extract of turmeric was taken and concentrated under reduced pressure to obtain 150 ml of turmeric concentrate, wherein the volume proportion of ethyl acetate was 60%, 18 ml of aqueous enzyme solution was added to the turmeric concentrate, wherein the content of protease in the aqueous enzyme solution was 0.3%, and the mixture was stirred evenly in a water bath at 48 ° C for 5 h, and then naturally allowed to stand for 3 h, and liquid-liquid separation was performed to obtain a turmeric hydrolyzate and an aqueous solution, and the turmeric hydrolyzate was subjected to the same reduced pressure concentration, crystallization, filtration and drying steps as described in Example 1 to obtain a curcumin product.

[0042] Example 4

[0043] This embodiment provides a process for increasing the yield of curcumin by enzymatic method, and the steps are as follows:

[0044] 2000 ml of ethyl acetate extract of turmeric was taken and concentrated under reduced pressure to obtain 171.43 ml of turmeric concentrate, wherein the volume proportion of ethyl acetate was 65%, 22.29 ml of aqueous enzyme solution was added to the turmeric concentrate, wherein the content of protease in the aqueous enzyme solution was 0.3%, and the mixture was stirred evenly in a water bath at 52 ° C for 5 h, and then naturally allowed to stand for 3 h, and liquid-liquid separation was performed to obtain a turmeric hydrolyzate and an aqueous solution, and the turmeric hydrolyzate was subjected to the same reduced pressure concentration, crystallization, filtration and drying steps as described in Example 1 to obtain a curcumin product.

[0045] Example 5

[0046] This embodiment provides a process for increasing the yield of curcumin by enzymatic method, and the steps are as follows:

[0047] 2000 ml of ethyl acetate extract of turmeric was taken and concentrated under reduced pressure to obtain 171.43 ml of turmeric concentrate, wherein the volume proportion of ethyl acetate was 65%, 22.29 ml of aqueous enzyme solution was added to the turmeric concentrate, wherein the content of amylase in the aqueous enzyme solution was 0.3%, and the mixture was stirred evenly in a water bath at 52 ° C for 5 h, and then naturally allowed to stand for 3 h, and liquid-liquid separation was performed to obtain a turmeric hydrolyzate and an aqueous solution, and the turmeric hydrolyzate was subjected to the same reduced pressure concentration, crystallization, filtration and drying steps as described in Example 1 to obtain a curcumin product.

[0048] Example 6

[0049] This embodiment provides a process for increasing the yield of curcumin by enzymatic method, and the steps are as follows:

[0050] 2000 ml of ethyl acetate extract of turmeric was taken and concentrated under reduced pressure to obtain 171.43 ml of turmeric concentrate, wherein the volume proportion of ethyl acetate was 65%, 22.29 ml of aqueous enzyme solution was added to the turmeric concentrate, wherein the content of cellulase in the aqueous enzyme solution was 0.3%, and the mixture was stirred evenly in a water bath at 52 ° C for 5 h, and then naturally allowed to stand for 3 h, and liquid-liquid separation was performed to obtain a turmeric hydrolyzate and an aqueous solution, and the turmeric hydrolyzate was subjected to the same reduced pressure concentration, crystallization, filtration and drying steps as described in Example 1 to obtain a curcumin product.

[0051] Example 7

[0052] This embodiment provides a process for increasing the yield of curcumin by enzymatic method, and the steps are as follows:

[0053] 2000 ml of ethyl acetate extract of turmeric was taken and concentrated under reduced pressure to obtain 171.43 ml of turmeric concentrate, wherein the volume proportion of ethyl acetate was 65%, 22.29 ml of aqueous enzyme solution was added to the turmeric concentrate, wherein the content of pectinase in the aqueous enzyme solution was 0.3%, and the mixture was stirred evenly in a water bath at 52 ° C for 5 h, and then naturally allowed to stand for 3 h, and liquid-liquid separation was performed to obtain a turmeric hydrolyzate and an aqueous solution, and the turmeric hydrolyzate was subjected to the same reduced pressure concentration, crystallization, filtration and drying steps as described in Example 1 to obtain a curcumin product.

[0054] Comparative Example 1

[0055] This comparative example provides an enzymatic process for improving the yield of curcumin, which is different from Example 1 only in that the volume proportion of ethyl acetate in the turmeric concentrate is 45%, and the other parameters and process are exactly the same.

[0056] Comparative Example 2

[0057] This comparative example provides an enzymatic process for improving the yield of curcumin, which differs from Example 2 only in that the volume proportion of ethyl acetate in the turmeric concentrate is 85%, and the other parameters and process are exactly the same.

[0058] Comparative Example 3

[0059] This comparative example provides a process for improving the yield of curcumin by enzymatic method, which is different from Example 1 only in that 10.8 ml of aqueous enzyme solution is added to the turmeric concentrate, and the other parameters and process are exactly the same.

[0060] Comparative Example 4

[0061] This comparative example provides a process for improving the yield of curcumin by enzymatic method, which is different from Example 2 only in that 48 ml of aqueous enzyme solution is added to the turmeric concentrate, and the other parameters and process are exactly the same.

[0062] Comparative Example 5

[0063] This comparative example provides a process for increasing the yield of curcumin by enzymatic method, which is different from Example 1 only in that the content of protease in the aqueous enzyme solution is 0.1%, and the other parameters and process are exactly the same.

[0064] Comparative Example 6

[0065] This comparative example provides a process for increasing the yield of curcumin by enzymatic method, which is different from Example 2 only in that the content of protease in the aqueous enzyme solution is 0.5%, and the other parameters and process are exactly the same.

[0066] Comparative Example 7

[0067] This comparative example provides a process for improving the yield of curcumin by an enzymatic method, which differs from Example 1 only in that the stirring time is 3 h, and the other parameters and process are exactly the same.

[0068] Comparative Example 8

[0069] This comparative example provides a process for improving the yield of curcumin by an enzymatic method, which differs from Example 2 only in that the stirring time is 7 h, and the other parameters and process are exactly the same.

[0070] The product data in each embodiment and comparative example are shown in Table 1.

[0071] Table 1 Curcumin content and yield in Examples and Comparative Examples

[0072]

[0073]

[0074] As can be seen from Table 1 above, in the embodiment, since the turmeric concentrate is treated with an aqueous enzyme solution, and then the water layer is removed by liquid-liquid separation, the turmeric concentrate is subjected to reduced pressure concentration, crystallization, filtration and drying steps, and the curcumin content is higher than 96%, and the curcumin yield is higher than 65%. Under the same preferred conditions of the volume ratio of ethyl acetate in the raw material, the effect of the protease enzymatic treatment on the yield improvement is better than that of cellulase, amylase and pectinase, and the curcumin yield is significantly improved.

[0075] Compared with the embodiment, in Comparative Examples 1 and 2, the proportion of ethyl acetate in the turmeric concentrate is too small, the viscosity of the turmeric concentrate is large, the enzymatic hydrolysis effect of the aqueous enzyme solution is poor, and the yield of curcumin is affected. On the contrary, the proportion of ethyl acetate is too large, the turmeric concentrate is dilute, the enzymatic hydrolysis reaction is insufficient, the yield of curcumin is also affected, and the actual production has more liquid, which will reduce the production efficiency and generate more wastewater.

[0076] Compared with the embodiment, in comparative examples 3 and 4, when the aqueous enzyme solution is used in the process of treatment, too little aqueous enzyme solution will reduce the effect of enzymolysis and the yield of curcumin. On the contrary, too much aqueous enzyme solution will not improve the yield and will increase the production cost.

[0077] Comparative Examples 5 and 6 show similar results and reasons to the aqueous enzyme solution dosage. Too little enzyme dosage reduces the yield, while too much does not significantly improve the curcumin yield.

[0078] Compared with the embodiment, the enzymolysis time in Comparative Examples 7 and 8 will affect the effect of the enzyme on substances such as protein or starch in the turmeric concentrate. A short enzymolysis time will weaken the effect, and a long enzymolysis time will have no obvious effect on improving the yield, but will prolong the time and reduce production efficiency.

[0079] Preferably, in an enzymatic process for increasing the yield of curcumin, it is necessary to take production applicability and economic feasibility as the starting point, comprehensively consider parameters such as the viscosity of the turmeric concentrate, the amount of aqueous enzyme solution and enzyme, the enzymatic hydrolysis time and the enzymatic hydrolysis temperature, so as to achieve the effects of improving production efficiency, shortening the process length and increasing the yield.

[0080] Although the present invention has been described in detail above with general descriptions and specific embodiments, it is obvious to those skilled in the art that some modifications or improvements may be made thereto based on the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention all fall within the scope of protection claimed by the present invention.

Claims

1. A method for obtaining curcumin, characterized in that: include: The method comprises taking ethyl acetate extract of turmeric as a raw material, mixing the raw material with an aqueous enzyme solution, stirring the raw material for reaction, standing the mixture to separate turmeric enzymatic hydrolysate and an aqueous solution, and subjecting the turmeric enzymatic hydrolysate to reduced pressure concentration, crystallization, filtration and drying to obtain a curcumin product. The volume ratio of ethyl acetate in the raw material is 50-80%. The enzyme in the aqueous enzyme solution is at least one of cellulase, amylase, protease and pectinase. When the raw material and the aqueous enzyme solution are mixed, the amount of the aqueous enzyme solution is 10-15% of the volume of the raw material. The content of the enzyme in the aqueous enzyme solution is 0.2-0.4%.

2. The method according to claim 1, characterized in that The temperature during full stirring reaction is 45-55°C, the stirring time is 4-6h, and the standing time is 2-4h.

3. The method according to any one of claims 1 to 2, characterized in that: The volume proportion of ethyl acetate in the raw material is 60-65%.

4. The method according to any one of claims 1 to 2, characterized in that: The enzyme in the aqueous enzyme solution is protease.

5. The method according to claim 3, characterized in that: The enzyme in the aqueous enzyme solution is protease.

6. The method according to any one of claims 1-2 and 5, characterized in that: When the raw material is mixed with the aqueous enzyme solution, the amount of the aqueous enzyme solution used is 12-13% of the volume of the raw material.

7. The method according to claim 3, characterized in that When the raw material is mixed with the aqueous enzyme solution, the amount of the aqueous enzyme solution used is 12-13% of the volume of the raw material.

8. The method according to claim 4, characterized in that When the raw material is mixed with the aqueous enzyme solution, the amount of the aqueous enzyme solution used is 12-13% of the volume of the raw material.

9. The method according to any one of claims 1-2, characterized in that: The temperature of the reaction was 48-52°C during full stirring.

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