Extraction liquid as well as preparation method and application thereof

Abstract

The invention relates to the technical field of indoleacetic acid extraction, and particularly discloses extract liquor as well as a preparation method and application thereof. The extraction liquid provided by the invention comprises ethyl lactate and tetrahydrofuran organic matters. In the extraction liquid provided by the invention, the ethyl lactate can well dissolve the indoleacetic acid from the fermentation liquid, and meanwhile, the tetrahydrofuran organic matter has proper polarity and chemical stability, so that the dissolving capacity of the indoleacetic acid is stronger by adjusting the overall polarity of the extraction liquid when the tetrahydrofuran organic matter is compounded with the ethyl lactate for use; therefore, the yield of the indoleacetic acid extracted from the fermentation liquor is further improved; besides, the extraction liquid compounded by ethyl lactate and tetrahydrofuran organic matters is used, so that co-extraction of impurities in the fermentation liquid can be avoided, and the yield and the purity of the indoleacetic acid during extraction are further improved.

Description

Technical Field

[0001] The invention relates to the technical field of indoleacetic acid extraction, and specifically discloses an extract, a preparation method and application thereof. Background Art

[0002] Indoleacetic acid, also known as 3-indoleacetic acid, is a plant growth hormone that plays a key role in plant growth and development. Composed of an indole ring and an acetic acid side chain, it is acidic, has a relative molecular mass of 175.19, and is moderately soluble in water. In agriculture, indoleacetic acid is used as a plant growth regulator to promote rooting of cuttings. In plant tissue culture, it is a common additive to culture media to induce cell dedifferentiation and redifferentiation, promoting rapid plant propagation and variety improvement. Therefore, research on the production of indoleacetic acid is of great significance.

[0003] Currently, the most common method for producing indoleacetic acid is chemical production, which primarily involves synthesizing indole under high temperature and pressure using the highly toxic catalyst potassium cyanide. This chemical production method not only pollutes the environment but also poses significant safety risks. Therefore, researchers have explored fermentation to produce indoleacetic acid. However, the indoleacetic acid in fermentation broths containing indoleacetic acid is difficult to separate during extraction, resulting in low extraction yields. Therefore, developing a method for extracting indoleacetic acid from indoleacetic acid fermentation broths is of great significance. Summary of the Invention

[0004] In view of the above problems, the present invention provides an extract and a preparation method and application thereof.

[0005] The first aspect of the present invention provides an application of an extract in extracting indoleacetic acid. The raw material for extracting indoleacetic acid is indoleacetic acid fermentation broth, and the extract comprises ethyl lactate and tetrahydrofuran organic matter.

[0006] Currently, commonly used extraction liquids mainly include ethyl acetate, ethanol, methanol, acetone, and diethyl ether. However, the inventors have shown through research that, when these extraction liquids are used alone or in combination as extraction agents to extract indoleacetic acid from fermentation broth, the purity and yield of the obtained product do not meet the expected results. Therefore, it is of great significance to provide a new extraction liquid to improve the purity and yield of indoleacetic acid extracted from indoleacetic acid fermentation broth.

[0007] During the research process, the inventors found that when ethyl lactate was used as the extraction liquid for extracting indoleacetic acid from the fermentation broth, the extraction yield was improved to a certain extent compared with commonly used extraction liquids such as methanol and ethyl acetate. However, after testing, the purity of the extraction was relatively low and did not meet expectations. Furthermore, after a large number of experimental studies, the inventors found that by adding tetrahydrofuran-like organic matter to ethyl lactate and using the mixed solution as the extraction liquid, the purity of the extracted indoleacetic acid was greatly improved, and its yield was also improved to a certain extent compared with the yield when ethyl lactate was used alone.

[0008] In the extract provided by the present invention, ethyl lactate can effectively dissolve indoleacetic acid from the fermentation broth. Meanwhile, tetrahydrofuran-type organic substances have suitable polarity and chemical stability. When used in combination with ethyl lactate, the overall polarity of the extract is adjusted, thereby enhancing the solubility of indoleacetic acid and further improving the yield of indoleacetic acid extracted from the fermentation broth. In addition, by using the extract composed of ethyl lactate and tetrahydrofuran-type organic substances, the present invention can also avoid the co-extraction of impurities in the fermentation broth, thereby improving the yield and purity of indoleacetic acid during extraction.

[0009] Preferably, the tetrahydrofuran organic compound is 2-methyltetrahydrofuran.

[0010] The present invention further limits the specific components of tetrahydrofuran organic matter, which is beneficial to further improve the purity and yield of indoleacetic acid.

[0011] Preferably, the mass ratio of ethyl lactate to tetrahydrofuran organic matter in the extract is (8.8-9.2):1.

[0012] The inventors have found through research that only when the ratio of ethyl lactate to tetrahydrofuran-like organic matter is controlled within a specific range can the two substances play a synergistic role and greatly improve the purity and yield of extracted indoleacetic acid.

[0013] A second aspect of the present invention provides a method for preparing the above-mentioned extract, comprising the following steps:

[0014] The weighed ethyl lactate and tetrahydrofuran organic matter are mixed evenly to obtain an extract.

[0015] A third aspect of the present invention provides a method for extracting indoleacetic acid, comprising the steps of:

[0016] S1. Filtering the indoleacetic acid fermentation broth through a ceramic membrane at 25° C. to 35° C. to obtain an indoleacetic acid filtrate;

[0017] S2. Concentrating the indoleacetic acid filtrate at 40° C. to 55° C. to obtain an indoleacetic acid concentrate;

[0018] S3. Adding the indoleacetic acid concentrate to the extract to perform extraction, distilling the extract, and drying to obtain indoleacetic acid.

[0019] Currently, methods for extracting indoleacetic acid primarily involve separating mycelium from a bacterial broth, extracting the broth with ethyl acetate, combining the extracts, and concentrating the extracts to obtain indoleacetic acid. However, the indoleacetic acid extracted using this method has low purity and yield, making it difficult to effectively extract indoleacetic acid from the fermentation broth. Therefore, it is of great significance to provide a method for extracting indoleacetic acid from a fermentation broth.

[0020] Compared with the prior art, the method for extracting indoleacetic acid from a fermentation broth provided by the present invention can ensure the stability of indoleacetic acid at a specific temperature, and can effectively remove most solid impurities and macromolecular impurities in the fermentation broth when filtering the indoleacetic acid fermentation broth using a ceramic membrane, thereby facilitating improved product purity and yield. Furthermore, the present invention concentrates the indoleacetic acid filtrate at a specific temperature, and this temperature range can prevent decomposition of indoleacetic acid or other side reactions caused by high temperature, thereby facilitating improved indoleacetic acid yield. Furthermore, by selecting a specific extraction liquid for extraction, the solubility of indoleacetic acid in the extraction liquid is greatly improved, and co-extraction of impurities in the fermentation broth can be avoided, further improving the purity and yield of indoleacetic acid during extraction.

[0021] Preferably, in S1, the concentration of indoleacetic acid in the indoleacetic acid fermentation broth is 2.5 g / L-2.8 g / L.

[0022] Preferably, in S1, the pore size of the ceramic membrane is 99 nm to 101 nm.

[0023] Preferably, in S2, the concentration method is evaporation concentration.

[0024] Preferably, in S2, the concentration of indoleacetic acid in the indoleacetic acid concentrate is 350 g / L to 380 g / L.

[0025] Preferably, in S3, the mass ratio of the indoleacetic acid concentrate to the extract is 1:(2-2.2).

[0026] By limiting the mass ratio of the indoleacetic acid concentrate to the extract, the solubility of indoleacetic acid in the extract can be maximized, co-extraction of impurities can be avoided, and the purity and yield of indoleacetic acid can be improved.

[0027] Preferably, in S3, the extraction is performed 3 to 4 times.

[0028] It should be further explained that after the extraction is completed, the extracts need to be combined and then distilled.

[0029] The method for extracting indoleacetic acid from indoleacetic acid fermentation broth provided by the present invention does not require special expensive materials, and has a simple process, low cost, a concise and clear operation process, mild extraction conditions, easy control, and does not require sophisticated equipment, which is conducive to industrial large-scale production. DETAILED DESCRIPTION

[0030] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0031] Example 1

[0032] This embodiment provides a method for extracting indoleacetic acid, comprising the following steps:

[0033] S1. Filtering an indoleacetic acid fermentation broth having a concentration of 2.5 g / L through a ceramic membrane having a pore size of 100 nm at 25° C. to obtain an indoleacetic acid filtrate;

[0034] S2. Concentrating the indoleacetic acid filtrate at 40° C. by evaporation to obtain an indoleacetic acid concentrate with a concentration of 350 g / L;

[0035] S3. Add the indoleacetic acid concentrate to the extract, extract three times, distill the extract, and dry to obtain indoleacetic acid; wherein the mass ratio of the indoleacetic acid concentrate to the extract is 1:2, and the extract is a mixture of ethyl lactate and 2-methyltetrahydrofuran in a mass ratio of 8.8:1.

[0036] Results: Based on the indoleacetic acid fermentation broth, the purity of indoleacetic acid was 84.3%, and the yield was 80.4%.

[0037] Example 2

[0038] This embodiment provides a method for extracting indoleacetic acid, comprising the following steps:

[0039] S1. Filtering an indoleacetic acid fermentation broth having a concentration of 2.8 g / L through a ceramic membrane having a pore size of 100 nm at 35° C. to obtain an indoleacetic acid filtrate;

[0040] S2. Concentrating the indoleacetic acid filtrate at 55° C. by evaporation to obtain an indoleacetic acid concentrate with a concentration of 380 g / L;

[0041] S3. Add the indoleacetic acid concentrate to the extract, extract four times, distill the extract, and dry to obtain indoleacetic acid; wherein the mass ratio of the indoleacetic acid concentrate to the extract is 1:2.2, and the extract is a mixture of ethyl lactate and 2-methyltetrahydrofuran in a mass ratio of 9.2:1.

[0042] Results: Based on the indoleacetic acid fermentation broth, the purity of indoleacetic acid was 84.3%, and the yield was 81.6%.

[0043] Example 3

[0044] This embodiment provides a method for extracting indoleacetic acid, comprising the following steps:

[0045] S1. Filtering an indoleacetic acid fermentation broth having a concentration of 2.6 g / L through a ceramic membrane having a pore size of 100 nm at 30° C. to obtain an indoleacetic acid filtrate;

[0046] S2. Concentrating the indoleacetic acid filtrate at 50° C. by evaporation to obtain an indoleacetic acid concentrate with a concentration of 370 g / L;

[0047] S3. Add the indoleacetic acid concentrate to the extract, extract for 4 times, distill the extract, and dry to obtain indoleacetic acid; wherein the mass ratio of the indoleacetic acid concentrate to the extract is 1:2.1, and the extract is a mixture of ethyl lactate and 2-methyltetrahydrofuran in a mass ratio of 9:1.

[0048] Results: Based on the indoleacetic acid fermentation broth, the purity of indoleacetic acid was 83.8%, and the yield was 81.9%.

[0049] Example 4

[0050] This embodiment provides a method for extracting indoleacetic acid, comprising the following steps:

[0051] S1. Filtering an indoleacetic acid fermentation broth having a concentration of 2.7 g / L through a ceramic membrane having a pore size of 100 nm at 32° C. to obtain an indoleacetic acid filtrate;

[0052] S2. Concentrating the indoleacetic acid filtrate at 45° C. by evaporation to obtain an indoleacetic acid concentrate with a concentration of 360 g / L;

[0053] S3. Add the indoleacetic acid concentrate to the extract, extract three times, distill the extract, and dry to obtain indoleacetic acid; wherein the mass ratio of the indoleacetic acid concentrate to the extract is 1:2, and the extract is a mixture of ethyl lactate and 2-methyltetrahydrofuran in a mass ratio of 9:1.

[0054] Results: Based on the indoleacetic acid fermentation broth, the purity of indoleacetic acid was 86.8%, and the yield was 82.9%.

[0055] Example 5

[0056] This embodiment provides a method for extracting indoleacetic acid, comprising the following steps:

[0057] S1. Filtering an indoleacetic acid fermentation broth having a concentration of 2.7 g / L through a ceramic membrane having a pore size of 100 nm at 32° C. to obtain an indoleacetic acid filtrate;

[0058] S2. Concentrating the indoleacetic acid filtrate at 45° C. by evaporation to obtain an indoleacetic acid concentrate with a concentration of 360 g / L;

[0059] S3. Add the indoleacetic acid concentrate to the extract, extract three times, distill the extract, and dry to obtain indoleacetic acid; wherein the mass ratio of the indoleacetic acid concentrate to the extract is 1:2, and the extract is a mixture of ethyl lactate and tetrahydrofuran in a mass ratio of 9:1.

[0060] Results: Based on the indoleacetic acid fermentation broth, the purity of indoleacetic acid was 80.4% and the yield was 74.1%.

[0061] Comparative Example 1

[0062] This comparative example provides a method for extracting indoleacetic acid, which differs from Example 1 in that ethyl lactate is replaced with an equal amount of ethyl acetate. Specifically:

[0063] S1. Filtering an indoleacetic acid fermentation broth having a concentration of 2.5 g / L through a ceramic membrane having a pore size of 100 nm at 25° C. to obtain an indoleacetic acid filtrate;

[0064] S2. Concentrating the indoleacetic acid filtrate at 40° C. by evaporation to obtain an indoleacetic acid concentrate with a concentration of 350 g / L;

[0065] S3. Add the indoleacetic acid concentrate to the extract, extract three times, distill the extract, and dry to obtain indoleacetic acid; wherein the mass ratio of the indoleacetic acid concentrate to the extract is 1:2, and the extract is a mixture of ethyl acetate and 2-methyltetrahydrofuran in a mass ratio of 8.8:1.

[0066] Results: Based on the indoleacetic acid fermentation broth, the purity of indoleacetic acid was 62.4%, and the yield was 34.5%.

[0067] Comparative Example 2

[0068] This comparative example provides a method for extracting indoleacetic acid. The difference from Example 1 is that 2-methyltetrahydrofuran is replaced by an equal amount of cyclopentyl methyl ether. Specifically:

[0069] S1. Filtering an indoleacetic acid fermentation broth having a concentration of 2.5 g / L through a ceramic membrane having a pore size of 100 nm at 25° C. to obtain an indoleacetic acid filtrate;

[0070] S2. Concentrating the indoleacetic acid filtrate at 40° C. by evaporation to obtain an indoleacetic acid concentrate with a concentration of 350 g / L;

[0071] S3. Add the indoleacetic acid concentrate to the extract, extract three times, distill the extract, and dry to obtain indoleacetic acid; wherein the mass ratio of the indoleacetic acid concentrate to the extract is 1:2, and the extract is a mixture of ethyl lactate and cyclopentyl methyl ether in a mass ratio of 8.8:1.

[0072] Results: Based on the indoleacetic acid fermentation broth, the purity of indoleacetic acid was 68.4%, and the yield was 48.6%.

[0073] Comparative Example 3

[0074] This comparative example provides a method for extracting indoleacetic acid. The difference from Example 1 is that 2-methyltetrahydrofuran is replaced with an equal amount of ethyl lactate. Specifically:

[0075] S1. Filtering an indoleacetic acid fermentation broth having a concentration of 2.5 g / L through a ceramic membrane having a pore size of 100 nm at 25° C. to obtain an indoleacetic acid filtrate;

[0076] S2. Concentrating the indoleacetic acid filtrate at 40° C. by evaporation to obtain an indoleacetic acid concentrate with a concentration of 350 g / L;

[0077] S3. Add the indoleacetic acid concentrate to the extract, extract three times, distill the extract, and dry to obtain indoleacetic acid; wherein the mass ratio of the indoleacetic acid concentrate to the extract is 1:2, and the extract is ethyl lactate.

[0078] Results: Based on the indoleacetic acid fermentation broth, the purity of indoleacetic acid was 73.5%, and the yield was 46.03%.

[0079] Comparative Example 4

[0080] This comparative example provides a method for extracting indoleacetic acid. The difference from Example 1 is that ethyl lactate is replaced with an equal amount of 2-methyltetrahydrofuran. Specifically:

[0081] S1. Filtering an indoleacetic acid fermentation broth having a concentration of 2.5 g / L through a ceramic membrane having a pore size of 100 nm at 25° C. to obtain an indoleacetic acid filtrate;

[0082] S2. Concentrating the indoleacetic acid filtrate at 40° C. by evaporation to obtain an indoleacetic acid concentrate with a concentration of 350 g / L;

[0083] S3. Add the indoleacetic acid concentrate to the extract, extract three times, distill the extract, and dry to obtain indoleacetic acid; wherein the mass ratio of the indoleacetic acid concentrate to the extract is 1:2, and the extract is 2-methyltetrahydrofuran.

[0084] Results: Based on the indoleacetic acid fermentation broth, the purity of indoleacetic acid was 70.6%, and the yield was 53.1%.

[0085] Comparative Example 5

[0086] This comparative example provides a method for extracting indoleacetic acid, which is different from Example 1 in that, in S2, the temperature is lowered to 35° C. Specifically:

[0087] S1. Filtering an indoleacetic acid fermentation broth having a concentration of 2.5 g / L through a ceramic membrane having a pore size of 100 nm at 25° C. to obtain an indoleacetic acid filtrate;

[0088] S2. Concentrating the indoleacetic acid filtrate at 35° C. by evaporation to obtain an indoleacetic acid concentrate with a concentration of 350 g / L;

[0089] S3. Add the indoleacetic acid concentrate to the extract, extract three times, distill the extract, and dry to obtain indoleacetic acid; wherein the mass ratio of the indoleacetic acid concentrate to the extract is 1:2, and the extract is a mixture of ethyl lactate and 2-methyltetrahydrofuran in a mass ratio of 8.8:1.

[0090] Results: Based on the indoleacetic acid fermentation broth, the purity of indoleacetic acid was 80.6%, and the yield was 70.3%.

[0091] By comparing Examples 1-5 and Comparative Examples 1-5, it can be seen that whether changing the composition of the extract or changing the extraction temperature during the extraction process, the final extraction purity and yield of indoleacetic acid will be affected. This also proves that the composite extract provided by the present invention combined with the extraction method provided by the present invention can significantly improve the yield and purity of indoleacetic acid.

[0092] 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 or improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. An application of an extract in extracting indoleacetic acid, characterized in that: The raw material for extracting indoleacetic acid is indoleacetic acid fermentation liquor, and the extract comprises ethyl lactate and tetrahydrofuran organic matter.

2. The use of the extract according to claim 1 in extracting indoleacetic acid, characterized in that: The tetrahydrofuran organic compound is 2-methyltetrahydrofuran.

3. Use of the extract according to claim 1 in extracting indoleacetic acid, characterized in that: The mass ratio of ethyl lactate to tetrahydrofuran organic matter in the extract is (8.8-9.2):

1.

4. A method for preparing the extract according to any one of claims 1 to 3, characterized in that: The steps include: The weighed ethyl lactate and tetrahydrofuran organic matter are mixed evenly to obtain an extract.

5. A method for extracting indoleacetic acid, characterized in that: The steps include: S1. Filtering the indoleacetic acid fermentation broth through a ceramic membrane at 25° C. to 35° C. to obtain an indoleacetic acid filtrate; S2. Concentrating the indoleacetic acid filtrate at 40° C. to 55° C. to obtain an indoleacetic acid concentrate; S3. Adding the indoleacetic acid concentrate to the extract according to any one of claims 1 to 3 for extraction, distilling the extract, and drying to obtain indoleacetic acid.

6. The method for extracting indoleacetic acid as claimed in claim 5, wherein In S1, the concentration of indoleacetic acid in the indoleacetic acid fermentation broth is 2.5 g / L-2.8 g / L.

7. The method for extracting indoleacetic acid as claimed in claim 5, wherein In S1, the pore size of the ceramic membrane is 99 nm to 101 nm.

8. The method for extracting indoleacetic acid as claimed in claim 5, wherein In S2, the concentration of indoleacetic acid in the indoleacetic acid concentrated solution is 350 g / L to 380 g / L.

9. The method for extracting indoleacetic acid as claimed in claim 5, wherein In S3, the mass ratio of the indoleacetic acid concentrate to the extract is 1:(2-2.2).

10. The method for extracting indoleacetic acid according to claim 5, wherein In S3, the extraction is performed 3 to 4 times.