Method for directly extracting nervonic acid from xanthoceras sorbifolia bunge

Abstract

The invention relates to the technical field of agriculture, in particular to a method for directly extracting nervonic acid from xanthoceras sorbifolia bunge, which comprises the following steps: A, crushing xanthoceras sorbifolia bunge; b, the raw materials obtained in the step A are put into a reaction tank to be saponified, and sodium nervonate saponification liquid is obtained; performing centrifugal solid-liquid separation to obtain a saponified solution; c, extracting the saponification liquid to obtain a nervonic acid sodium salt solution; d, pouring the nervonic acid sodium salt solution into an acid precipitation tank for acid precipitation to obtain a mixed acid precipitation solution; e, filtering the mixed acid eluate to obtain a filtrate which is a mixed acid solution; f, adding the mixed acid liquid into diethyl ether, and crystallizing to obtain a nervonic acid crude product; g, adding acetone into the nervonic acid crude product for crystallization to obtain a nervonic acid purified product; and H, adding petroleum ether into the nervonic acid purified product, and crystallizing to obtain a nervonic acid pure product. According to the method, shiny-leaved yellowhorn is directly used as an extraction raw material, high-purity nervonic acid can be obtained through an efficient and environment-friendly extraction mode, and the extraction efficiency can reach 0.6%-0.72%.

Description

Technical Field

[0001] The present invention relates to the field of agricultural technologies, and particularly to a method for directly extracting nervonic acid from Xanthoceras sorbifolia Bunge. Background Art

[0002] Nervonic acid, also known as shark acid, with the chemical name cis-15-tetracosenoic acid, is a type of ω-9 monounsaturated fatty acid. It is named because it was first discovered in the nerve tissues of mammals. Nervonic acid is a functional fatty acid in the nervous system of vertebrates. It can completely penetrate the blood-brain barrier. It can restore the neural network system by inducing the self-growth and division of nerve fibers, ensuring the normal function of the brain nerve center. Therefore, nervonic acid can, to a certain extent, promote brain development, enhance memory and cognitive functions, enhance immunity, and prevent and treat brain diseases, showing good development prospects in both the medical and health care fields.

[0003] Currently, most commercially available nervonic acid is extracted from deep-sea shark oil, resulting in high production costs and expensive prices. The chemical synthesis route and process of nervonic acid are complex, with low yields and unable to achieve industrialization. Xanthoceras sorbifolia Bunge belongs to the Sapindaceae family and is a deciduous shrub or small tree of the genus Xanthoceras. It is mainly distributed in northern China and is a unique woody oil tree species in China. The oil content of Xanthoceras sorbifolia Bunge seeds is about 35%, and the oil content of the kernels is over 60%. Xanthoceras sorbifolia Bunge oil is an edible vegetable oil rich in unsaturated fatty acids. In addition to oleic acid and linoleic acid, it also contains nervonic acid, with a content of about 3%.

[0004] Therefore, the Chinese invention patent with the publication number CN115124416B discloses a method for extracting nervonic acid from Xanthoceras sorbifolia Bunge, including the following steps: S1. Obtain Xanthoceras sorbifolia Bunge oil from the kernels of Xanthoceras sorbifolia Bunge; S2. Mix and stir the Xanthoceras sorbifolia Bunge oil with isopropanol and triethylamine, let it stand at room temperature, wash with water until it is clear, adjust the pH to 3 - 5 to obtain a mixed solution; S3. Add an extraction agent to the mixed solution for extraction, wash with water until it is neutral, distill to obtain a fatty acid mixed solution, and dry to obtain crude nervonic acid; S4. Dissolve the crude nervonic acid in petroleum ether and chloroform, add 0.1 - 0.5 wt% activated carbon and stir, heat under reflux, filter and concentrate to obtain a concentrated solution; S5. Adjust the pH of the concentrated solution to 4 - 5, crystallize and purify, filter, and dry to obtain nervonic acid. Through the above technical solution, the problems of high production cost, complex operation, and low extraction purity of nervonic acid in the prior art are solved.

[0005] A Chinese invention patent application with publication number CN117486719A discloses a method for extracting high-purity neurite esters from Xanthoceras sorbifolia seed kernels. The method comprises a multi-stage vacuum distillation and urea inclusion complexation process. The Xanthoceras sorbifolia seed kernels are first mechanically pressed to obtain Xanthoceras sorbifolia crude oil, which is then degummed, deacidified, and dehydrated to obtain Xanthoceras sorbifolia seed oil. The Xanthoceras sorbifolia seed oil is then subjected to an ester exchange reaction, followed by separation and water washing to obtain mixed fatty acid esters. The mixed fatty acid esters are subjected to multi-stage vacuum distillation under suitable conditions to obtain heavy components, which are then subjected to solvent extraction to obtain crude neurite esters. Finally, the crude neurite esters are further separated and purified using urea inclusion complexation to obtain a high-purity neurite ester product.

[0006] However, the extraction methods disclosed in the prior art are complex and require the use of highly polluting chloroform, resulting in high production costs and severe environmental pressure. Therefore, how to extract nervonic acid in an environmentally friendly and efficient manner remains a technical problem that needs to be solved urgently by those skilled in the art. Summary of the Invention

[0007] In view of this, the present invention provides a method for directly extracting nervonic acid from Xanthoceras sorbifolia. To achieve the above object, the present invention mainly provides the following technical solutions: A method for directly extracting nervonic acid from Xanthoceras sorbifolia L. comprises the following steps: A. Crush the Xanthoceras sorbifolia into 20-40 mesh; B. Place the raw materials obtained in step A into a reaction tank, add 2-4 times the weight of a 10-15 wt% sodium hydroxide solution, stir evenly, heat to 55-65° C., add 3-7 times the weight of a 10-15 wt% sodium hydroxide solution while stirring, and react for 160-200 minutes to obtain a sodium neuraminic acid saponified solution; and separate the solid and liquid by centrifugation to obtain a saponified solution. C. Add 2-4 volumes of ether and / or petroleum ether to the saponified solution obtained in step B to extract the sodium neuraminic acid saponified solution, recover the ether solution, and obtain a sodium neuraminic acid salt solution; D. Pour the sodium nervonic acid salt solution into an acid precipitation tank, stir, and dropwise add sulfuric acid and / or hydrochloric acid at a concentration of 6-10 wt % to neutralize to a pH of 6.5-7.5, and precipitate a white mixed acid precipitation liquid to obtain a mixed acid precipitation liquid; E. Filter the mixed acid precipitate to obtain a filtrate, which is a mixed acid solution; F. Add the mixed acid solution to 2-4 volumes of diethyl ether, filter out the insoluble acid to obtain an ether filtrate, cool the ether filtrate to -6-10°C to precipitate nervonic acid, and filter to obtain a crude nervonic acid; G. Dissolve the crude nervonic acid in 2-4 volumes of acetone, filter out the insoluble acid to obtain an acetone filtrate, cool the acetone filtrate to -6-10°C to allow crystallization, precipitate the nervonic acid, and filter to obtain the purified nervonic acid; H. Add the purified nervonic acid to petroleum ether with a volume 2 - 4 times that of the nervonic acid, filter out the insoluble acids to obtain a petroleum ether filtrate, cool the petroleum ether filtrate to -6 to -10 °C, precipitate the nervonic acid, and filter to obtain pure nervonic acid.

[0008] In a preferred embodiment of the present invention, in step A, the Xanthoceras sorbifolia Bunge is crushed to 30 mesh.

[0009] In a preferred embodiment of the present invention, in step C, add ether with a volume 2 - 4 times that of the sodium nervonate saponification solution to the sodium nervonate saponification solution for extraction, recover the ether solution to obtain a sodium nervonate solution; In a preferred embodiment of the present invention, in step D, pour the sodium nervonate solution into an acid precipitation tank, stir and dropwise add sulfuric acid and / or hydrochloric acid with a concentration of 6 - 10 wt% to neutralize to a pH of 6.8 - 7.2, precipitate the white mixed acid precipitation solution to obtain a mixed acid precipitation solution.

[0010] Compared with the prior art, the beneficial effects of the present invention are: The present invention directly uses Xanthoceras sorbifolia Bunge as the extraction raw material, and through an efficient and environmentally friendly extraction method, nervonic acid with a high purity (above 96.9%, preferably above 97.8%) can be obtained, and the extraction efficiency can reach 0.6 - 0.72%. Specific Embodiments

[0011] To further illustrate the technical means and effects adopted by the present invention to achieve the intended invention purpose, the following takes preferred embodiments to detail the specific implementation manners, technical solutions, features and their effects of the application according to the present invention as follows. Specific features, structures, or characteristics in the following descriptions of multiple embodiments can be combined in any suitable form.

[0012] Example 1 A method for directly extracting nervonic acid from Xanthoceras sorbifolia Bunge, comprising the following steps: A. Crush the Xanthoceras sorbifolia Bunge to 30 mesh; B. Put the raw material obtained in step A into a reaction tank, add a sodium hydroxide solution with a concentration of 13 wt% and a weight 3 times that of the raw material, stir evenly, heat to 60 °C, and while stirring, add a sodium hydroxide solution with a concentration of 13 wt% and a weight 5 times that of the raw material, react for 180 min to obtain a sodium nervonate saponification solution; perform centrifugal solid-liquid separation to obtain the saponification solution; C. Add ether with a volume 3 times that of the saponification solution obtained in step B to the sodium nervonate saponification solution for extraction, recover the ether solution to obtain a sodium nervonate solution; D. Pour the sodium nervonate solution into an acid precipitation tank, stir and dropwise add sulfuric acid with a concentration of 8 wt% to neutralize to a pH of 7, precipitate the white mixed acid precipitation solution to obtain a mixed acid precipitation solution; E. Filter the mixed acid precipitation solution to obtain a filtrate, which is a mixed acid solution; F. Add the mixed acid solution to 3 volumes of diethyl ether, filter out the insoluble acid to obtain a diethyl ether filtrate, cool the diethyl ether filtrate to -8°C, nervonic acid precipitates, and filter to obtain crude nervonic acid; G. Dissolve the crude nervonic acid in 3 volumes of acetone, filter out the insoluble acid to obtain an acetone filtrate, cool the acetone filtrate to -8°C for crystallization, nervonic acid precipitates, and filter to obtain purified nervonic acid; H. Add the purified nervonic acid to 3 volumes of petroleum ether, filter out the insoluble acid to obtain a petroleum ether filtrate, cool the petroleum ether filtrate to -8°C, nervonic acid precipitates, and filter to obtain pure nervonic acid; Through GC-MS analysis, the purity of nervonic acid was identified as 97.83 wt%, and the extraction rate of nervonic acid: weight of nervonic acid / weight of Xanthoceras sorbifolia Bunge = 0.72%.

[0013] Example 2 Same as Example 1, except that hydrochloric acid with the same concentration was used instead of sulfuric acid in step D. Through GC-MS analysis, the purity of nervonic acid was identified as 97.25 wt%, and the extraction rate of nervonic acid: weight of nervonic acid / weight of Xanthoceras sorbifolia Bunge = 0.63%.

[0014] Example 3 Same as Example 1, except that petroleum ether with the same amount was used instead of diethyl ether in step C. Through GC-MS analysis, the purity of nervonic acid was identified as 96.92 wt%, and the extraction rate of nervonic acid: weight of nervonic acid / weight of Xanthoceras sorbifolia Bunge = 0.61%.

[0015] Comparative Example 1 Same as Example 1, except that steps F and H were exchanged, that is, petroleum ether extraction was carried out first, and then diethyl ether extraction was carried out. Through GC-MS analysis, the purity of nervonic acid was identified as 95.31 wt%, and the extraction rate of nervonic acid: weight of nervonic acid / weight of Xanthoceras sorbifolia Bunge = 0.41%.

[0016] Comparative Example 2 Same as Example 1, except that petroleum ether / chloroform with the same amount and a volume ratio of 1:1 was used instead of petroleum ether in step H. Through GC-MS analysis, the purity of nervonic acid was identified as 96.83 wt%, and the extraction rate of nervonic acid: weight of nervonic acid / weight of Xanthoceras sorbifolia Bunge = 0.54%.

[0017] The above disclosure is only the specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of changes or substitutions, which should all be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the above-mentioned claims.

Claims

1. A method for directly extracting nervonic acid from Xanthoceras sorbifolium Bunge, characterized in that, It includes the following steps: A. Crush the Xanthoceras sorbifolium Bunge to 20 - 40 mesh; B. Put the raw material obtained in step A into a reaction tank, add a sodium hydroxide solution with a concentration of 10 - 15 wt% and a weight 2 - 4 times that of the raw material, stir evenly, heat to 55 - 65 °C, and while stirring, add a sodium hydroxide solution with a concentration of 10 - 15 wt% and a weight 3 - 7 times that of the raw material, and react for 160 - 200 min to obtain a nervonic acid saponification solution; Through centrifugal solid - liquid separation, a saponification solution is obtained; C. Add 2 - 4 times the volume of ether and / or petroleum ether to the saponification solution obtained in step B, extract the nervonic acid saponification solution, recover the ether solution, and obtain a nervonic acid sodium salt solution; D. Pour the nervonic acid sodium salt solution into an acid precipitation tank, stir and dropwise add sulfuric acid and / or hydrochloric acid with a concentration of 6 - 10 wt%, neutralize to a pH of 6.5 - 7.5, and precipitate the white mixed acid precipitation solution to obtain a mixed acid precipitation solution; E. Filter the mixed acid precipitation solution to obtain a filtrate, and the filtrate is a mixed acid solution; F. Add the mixed acid solution to 2 - 4 times the volume of ether, filter out the insoluble acid to obtain an ether filtrate; cool the ether filtrate to - 6 - 10 °C, nervonic acid precipitates, and filter to obtain a crude nervonic acid product; G. Dissolve the crude nervonic acid product in 2 - 4 times the volume of acetone, filter out the insoluble acid to obtain an acetone filtrate; cool the acetone filtrate to - 6 - 10 °C and crystallize, nervonic acid precipitates, and filter to obtain a purified nervonic acid product; H. Add the purified nervonic acid product to 2 - 4 times the volume of petroleum ether, filter out the insoluble acid to obtain a petroleum ether filtrate; cool the petroleum ether filtrate to - 6 - 10 °C, nervonic acid precipitates, and filter to obtain a pure nervonic acid product.

2. The method for directly extracting nervonic acid from Xanthoceras sorbifolium Bunge according to claim 1, wherein In step A, the Xanthoceras sorbifolium Bunge is crushed to 30 mesh.

3. The method for directly extracting nervonic acid from Xanthoceras sorbifolium Bunge according to claim 1, characterized in that, Step C is to add 2 - 4 times the volume of ether to the nervonic acid saponification solution, extract the nervonic acid saponification solution, recover the ether solution, and obtain a nervonic acid sodium salt solution.

4. The method for directly extracting nervonic acid from Xanthoceras sorbifolium Bunge according to claim 1, characterized in that, Step D is to pour the nervonic acid sodium salt solution into an acid precipitation tank, stir and dropwise add sulfuric acid and / or hydrochloric acid with a concentration of 6 - 10 wt%, neutralize to a pH of 6.8 - 7.2, and precipitate the white mixed acid precipitation solution to obtain a mixed acid precipitation solution.

5. The method for directly extracting nervonic acid from Xanthoceras sorbifolium Bunge according to any one of claims 1-4, characterized in that The purity of the pure nervonic acid product is above 96.9%.

6. The method for directly extracting nervonic acid from Xanthoceras sorbifolium Bunge according to any one of claims 1-4, characterized in that, The purity of the pure nervonic acid product is above 97.8%.

7. The method for directly extracting nervonic acid from Xanthoceras sorbifolium Bunge according to any one of claims 1-4, characterized in that, The extraction rate of the nervonic acid is 0.6 - 0.72%, and the extraction rate refers to the weight of the pure nervonic acid product / the weight of the Xanthoceras sorbifolium Bunge.