A method for simultaneous extraction of soybean amino acids and fatty acids

Abstract

This invention relates to the field of biotechnology, and in particular to a method for simultaneously extracting amino acids and fatty acids from soybeans. The method first uses n-hexane to extract ground soybean powder, separating it into a supernatant (containing oil) and a precipitate (containing protein). These are then digested separately using a microwave digester to convert the precipitate into fatty acids and amino acids. This method achieves the extraction of amino acids and fatty acids with a relatively small soybean sample volume. Compared to traditional standard methods, this method eliminates complex operational steps, greatly simplifies sample pretreatment, saves sample volume, and improves quantitative accuracy. Compared to traditional standard methods, it significantly saves time and cost. Furthermore, it provides a reference method for the extraction of protein and oil components. Moreover, the analytical method used in this invention can also be applied to the analysis of amino acids and fatty acids in other media. Practical experience has verified that this is an ideal and feasible method.

Description

Technical Field

[0001] This invention relates to the field of biotechnology, and in particular to a method for simultaneously extracting amino acids and fatty acids from soybeans. Background Technology

[0002] Soybean (Glycine max L.) seeds contain approximately 35%-45% crude protein and 30%-40% total amino acids, including all eight essential amino acids required by the human body. Soybean protein and amino acids are not only widely used in food, health products, and special medical purpose formula foods, but are also irreplaceable functional raw materials in fermentation, cosmetics, and animal nutrition. Therefore, achieving efficient and simultaneous extraction of both crude protein and total amino acids from soybeans is of significant industrial importance for improving raw material utilization, reducing production costs, and simplifying subsequent purification steps.

[0003] Currently, the soybean fatty acid / amino acid extraction routes reported in industry and literature can be broadly classified into three categories:

[0004] Category 1, Alkali Dissolution and Acid Precipitation (Traditional Precipitation Method): This method only yields crude protein (precipitated by acid precipitation), while a large amount of free amino acids and small peptides in the supernatant are directly discharged without precipitation, resulting in a total amino acid recovery rate of <10%. Category 2, Enzymatic Hydrolysis-Membrane Separation Method: This method has a long process chain, severe membrane fouling, and frequent cleaning, resulting in a continuous production cycle of ≤24 hours, limiting industrial scale-up. Category 3, Solvent Stepwise Extraction Method: Ultrafiltration membranes have a retention rate of <15% for free amino acids (molecular weight <200 Da), with a large amount of amino acids lost with the permeate, requiring subsequent ion exchange or electrodialysis for enrichment. Furthermore, all of the above methods share the common drawback of "being unable to simultaneously extract crude protein and total amino acids."

[0005] Meanwhile, hydrochloric acid is often used to hydrolyze soybean protein during extraction. However, the strong oxidizing properties of hydrochloric acid can lead to the degradation of amino acids such as tryptophan, resulting in a decrease in the content of sensitive amino acids such as tryptophan. Furthermore, there is no extraction method specifically for C16:0 (palmitic acid), C18:0 (stearic acid), C18:1 (oleic acid), C18:2 (linoleic acid), and C18:3 (linolenic acid).

[0006] Based on the above-mentioned technical obstacles, the present invention aims to provide a technical solution for the simultaneous extraction of specific fatty acids (C16:0, C18:0, C18:1, C18:2 and C18:3) and total amino acids from soybeans. Summary of the Invention

[0007] The purpose of this invention is to provide a method for simultaneously extracting soybean amino acids and fatty acids, thereby solving the problems existing in the prior art. The method provided by this invention can extract specific fatty acids from soybeans—C16:0, C18:0, C18:1, C18:2, and C18:3—while also increasing the content of sensitive amino acids in soybeans.

[0008] To achieve the above objectives, the present invention provides the following solution:

[0009] This invention provides a method for simultaneously extracting amino acids and fatty acids from soybeans, comprising the following steps:

[0010] Soybeans and n-hexane were mixed and then subjected to sonication and centrifugation to obtain supernatant and precipitate.

[0011] After the supernatant is evaporated to dryness, NaOH solution is added for digestion to obtain the fatty acid;

[0012] The precipitate, methanesulfonic acid solution, and antioxidant were mixed and digested to obtain the amino acid.

[0013] The digestion temperature in the system for extracting the fatty acids was 110℃ and the time was 40 min; the digestion temperature in the system for extracting the amino acids was 120℃ and the time was 40 min.

[0014] Preferably, the fatty acids include C16:0, C18:0, C18:1, C18:2, and C18:3.

[0015] Preferably, the concentration of methanesulfonic acid in the methanesulfonic acid solution is 4M; the antioxidant comprises a 0.2% by volume solution of 3-mercaptopropionic acid and a 0.05% by mass EDTA powder.

[0016] Preferably, the mass-to-volume ratio of the precipitate, the methanesulfonic acid solution, the 3-mercaptopropionic acid solution, and the EDTA powder is 100 mg: 3 mL: 6 μL: 1.5 μg.

[0017] Preferably, the concentration of NaOH in the NaOH solution is 6M; based on the mass of the soybeans in step (1), the mass-to-volume ratio of the soybeans to the NaOH solution is 100mg:3mL.

[0018] Preferably, when extracting the fatty acids, the digestion process further includes adjusting the pH of the digestate to less than 5.

[0019] Preferably, when extracting the amino acids, the digestion process further includes adjusting the pH of the digestate to 7.

[0020] Preferably, the mass-to-volume ratio of soybean to n-hexane is 100 mg: 1.5 mL; the centrifugation force is 12,000 × g, the time is 10 min, and the temperature is 4 °C.

[0021] The present invention discloses the following technical effects:

[0022] In soybean breeding and quality improvement research, the detection and analysis of high-oil and high-protein related metabolites are crucial. High-throughput detection technology can rapidly and accurately obtain the content and composition information of metabolites such as oil and protein in soybeans, providing a scientific basis for quality breeding. Based on this, this invention provides a method for simultaneously extracting amino acids and fatty acids from soybeans. This method first uses n-hexane to extract ground soybean powder, separating it into a supernatant (containing oil) and a precipitate (containing protein). These are then digested separately using a microwave digester to convert them into fatty acids and amino acids. Subsequently, liquid chromatography-mass spectrometry (LC-MS) is used to accurately quantify 22 amino acids and 5 fatty acids in soybeans. This method achieves the extraction of amino acids and fatty acids with a relatively small soybean sample size. Compared with traditional standard methods such as Soxhlet extraction and Kjeldahl nitrogen determination, this method utilizes microwave digestion to rapidly hydrolyze proteins and oils into total amino acids and fatty acids, and finally uses LC-MS for precise quantification. This method eliminates the need for complex procedures, greatly simplifies sample pretreatment, saves sample volume, and improves quantification accuracy. Compared with traditional standard methods, it significantly saves time and cost. It also provides a reference method for the extraction of protein and lipid components. Furthermore, the analytical method (liquid chromatography-mass spectrometry) in the specific embodiments of this invention can also be applied to the analysis of amino acids and fatty acids in other media. Practical experience has verified that this is an ideal and feasible method.

[0023] The specific advantages are as follows:

[0024] (1) Simultaneously obtain the total amount and composition of oil and protein: Soybean fatty acid components (C16:0, C18:0, C18:1, C18:2 and C18:3) account for about 92-97% of the total fatty acids. Detecting 5 fatty acids can simultaneously obtain the precise content of oil and components. Soybean protein is composed entirely of amino acids. Detecting 22 amino acids can simultaneously obtain the precise content of protein and components, which is more conducive to guiding nutritional optimization or functional product development.

[0025] (2) The present invention requires a small sample size. The amino acids and fatty acids are extracted from the same soybean sample. The relative repeatability and parallelism between the two are better than those extracted separately, which facilitates data integration when studying related metabolic pathways.

[0026] (3) The quantification is accurate, and the detection has high specificity and sensitivity when analyzing trace biological samples.

[0027] (4) The pretreatment time is relatively short. Compared with the traditional standard method of extracting oil by Soxhlet extraction, which takes 6-24 hours per extraction and extracting protein by Kjeldahl extraction, which takes more than 4 hours per extraction, the microwave digester of this invention can extract in about 1.5 hours per extraction, which can significantly improve throughput and meet the needs of modern large-scale breeding.

[0028] (5) The extraction process does not require derivatization reaction, which effectively shortens the reaction time and reduces the generation of by-products, thereby improving the recovery rate of amino acids and fatty acids and ensuring high repeatability.

[0029] (6) The solvent used in this invention has low toxicity and will not produce toxic gases. Furthermore, all strong acids and bases are digested in a closed system, which ensures high safety.

[0030] (7) The extractant used in the amino acid extraction process is methanesulfonic acid, which is a strong organic acid with much lower oxidizing power than hydrochloric acid. It has a high tryptophan recovery rate and can achieve high-throughput extraction with low reagent consumption. The existing technology uses hydrochloric acid as the extractant, which completely destroys tryptophan and is more corrosive to the instrument than methanesulfonic acid. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 A flowchart for extracting total amino acids and fatty acids from soybeans;

[0033] Figure 2 A comparative experiment on the extraction of amino acids using hydrochloric acid (HCl) and methanesulfonic acid (MSA);

[0034] Figure 3 A comparative experiment of water bath heating and microwave digestion of methanesulfonic acid;

[0035] Figure 4 This is a comparative experiment of NaOH water bath heating and microwave digestion;

[0036] Figure 5 Optimize the conditions for microwave digestion-assisted mesylate hydrolysis extraction of Lysine (A), Methionine (B), Alanine (C), and Serine (D).

[0037] Figure 6Optimization of microwave digestion-assisted mesylate hydrolysis extraction conditions for Tryptophan (A), Glycine (B), Proline (C) and Valine (D);

[0038] Figure 7 Optimize the conditions for microwave digestion-assisted mesylate hydrolysis extraction of Threonine (A), Cysteine ​​(B), Aspartic acid (C) and Tyramine (D);

[0039] Figure 8 Optimize the conditions for microwave digestion-assisted mesylate hydrolysis extraction of leucine (A), isoleucine (B), glutamine (C), and glutamic acid (D).

[0040] Figure 9 Optimization of microwave digestion-assisted mesylate hydrolysis extraction conditions for Histidine (A), Tryptamine (B), Tyrosine (C), and Cystine (D);

[0041] Figure 10 Microwave digestion-assisted mesylate hydrolysis was used to extract phenylalanine (A) and arginine (B).

[0042] Figure 11 Optimization of conditions for microwave digestion-assisted NaOH hydrolysis extraction of fatty acids; where A represents the loudness intensity of C16:0 under different treatments; B represents the relative intensity of C18:0 under different treatments; C represents the relative intensity of C18:1 under different treatments; D represents the relative intensity of C18:2 under different treatments; and E represents the relative intensity of C18:3 under different treatments. Detailed Implementation

[0043] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0044] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any stated value or intermediate value within a stated range, as well as each smaller range between any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0045] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0046] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be apparent to those skilled in the art. This specification and embodiments are merely exemplary.

[0047] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0048] Example 1: Verifying the advantages of using methanesulfonic acid to hydrolyze proteins in the method of the present invention.

[0049] To fully preserve sensitive amino acids (such as tryptophan), this invention uses methanesulfonic acid (MSA) for protein hydrolysis. While some reports use hydrochloric acid for hydrolysis, its strong oxidizing properties easily lead to the degradation of amino acids such as tryptophan. Methanesulfonic acid, on the other hand, can gently break peptide bonds, effectively protecting easily damaged groups and thus significantly improving detection accuracy.

[0050] A method for extracting amino acids from soybeans, comprising the following steps:

[0051] Weigh out soybean powder and add 1.5 mL of n-hexane to centrifuge tubes 1 and 2, which each contain 100 mg of soybean powder. Sonicate the mixture (sonication is maintained at 10°C, vortexing for 10 seconds every 10 minutes, for a total of 30 minutes). Centrifuge at 12000 × g for 10 minutes at 4°C. Collect the supernatant. Vacuum dry the precipitate in the centrifuge tubes (vacuum centrifuge concentrator). Add 3 mL of 4 M hydrochloric acid to centrifuge tube 1 and 3 mL of 4 M methanesulfonic acid solution (solvent is water) to centrifuge tube 2. 6 μL of 0.2% (v / v) 3-mercaptopropionic acid solution and 1.5 μg of 0.05% (w / w) EDTA powder were added to two centrifuge tubes. The 0.2% (v / v) 3-mercaptopropionic acid solution and 0.05% (w / w) EDTA powder served as antioxidants. The mixtures were then transferred to sealed glass containers and heated in a water bath at 100°C for 4 hours. After the reaction was complete, the reaction was terminated by an ice-water bath. The pH was adjusted to approximately 7, the mixture was filtered, and the samples were analyzed by LC-MS.

[0052] LC-MS detection UPLC analysis conditions include: column, phenomenex C10 ... 18 (Kinetex 2.6 µm PolarC) 18 100 Å, 100*2.1mm), pre-column, phenomenex C 18 (Kinetex 2.6 µm Polar C) 18100 Å (5*2.1 mm); Mobile phase: Phase A was water (with 0.04% acetic acid added), Phase B was methanol (with 0.04% acetic acid added), with 10 ppb lidocaine added to the mobile phase to monitor instrument stability; Elution gradient: water:methanol, 0 min 95:5 V / V, 11.0 min 0:100 V / V, 15.0 min 0:100 V / V, 15.5 min 100:0 V / V, 20.0 min 95:5 V / V; Flow rate: 0.40 mL / min; Column temperature: 40 ℃; Injection volume: 2 μL. Mass spectrometry analysis was performed using LC-ESI-Q TRAP-MS / MS (AppliedBiosystems Sciex 6500+). Mass spectrometry was used for data acquisition with the following settings: ion source gas 1, 55 psi; ion source gas 2, 55 psi; curtain gas, 35 psi; ion source temperature 450 ℃; electrospray voltage, 5500 V. The scan mode was MRM, residence time 5-20 ms, and total cycle time was fixed at 1 s. The acquired data were processed using Analyst 1.7.3 software. This invention utilizes LC-MS for detection, enabling precise and rapid specific detection of multiple amino acids and fatty acid components in samples. It offers advantages such as simplicity, speed, high sensitivity, good specificity, and good repeatability.

[0053] Results: Comparative experiments using methanesulfonic acid and hydrochloric acid as extraction solutions showed that, in tryptophan detection, the relative content of tryptophan extracted with methanesulfonic acid was more than 5 times higher than that extracted with hydrochloric acid. This indicates that hydrochloric acid destroys the tryptophan structure, leading to a lower recovery rate. Lysine and histidine also showed higher recovery rates in the methanesulfonic acid extraction method, while the recovery rates of other amino acids did not change significantly. These results suggest that methanesulfonic acid is more favorable as an extraction solution for amino acid extraction and analysis, while the strong oxidizing properties of hydrochloric acid can lead to the degradation of some amino acids. Figure 2 ).

[0054] Example 2: Verifying the advantages of the method of the present invention using microwave digestion for rapid extraction

[0055] Based on Example 1, methanesulfonic acid (MSA) was selected as the extraction solvent for amino acids, and fatty acid samples were treated with NaOH solution. To improve hydrolysis efficiency, a microwave digester was used instead of traditional water bath heating. By comparing the processing times of the two methods, the accelerating effect of microwave technology on extraction throughput was clarified.

[0056] A method for simultaneously extracting amino acids and fatty acids from soybeans, the process is as follows: Figure 1 As shown, the steps are as follows:

[0057] (1) Amino acid extraction and detection: Prepare two centrifuge tubes (centrifuge tube 1 and centrifuge tube 2) containing 100 mg of soybean powder, add 1.5 mL of n-hexane to each, sonicate (sonication at 10℃, vortex for 10 s every 10 min, 3 times for a total of 30 min), centrifuge at 12000×g for 10 min at 4℃, and set aside the supernatant (for fatty acid extraction, dispensed into centrifuge tube 3 and centrifuge tube 4). Vacuum dry the precipitate in the centrifuge tubes (vacuum centrifuge concentrator), add 3 mL of 4 M methanesulfonic acid solution, then add 6 μL of 0.2% 3-mercaptopropionic acid solution and 1.5 μg of 0.05% EDTA powder, where the 0.2% 3-mercaptopropionic acid solution and 0.05% EDTA powder are used as antioxidants. The sample in centrifuge tube 1 was transferred to a sealed glass bottle and heated in a water bath at 100°C for 4 hours. The reagent in centrifuge tube 2 was transferred to a digestion vessel and digested using a microwave digestion system (Anton Paar, Multiware PRO microwave digestion system) at 160°C for 1.5 hours (0-10 min, heating from 0°C to 160°C; 10-80 min, holding at 160°C for 70 min; 80-90 min, cooling from 160°C to room temperature). At least three biological replicates were performed to ensure the reliability of the results. After the reaction was completed, the pH was adjusted to approximately 7, filtered, and the sample was injected into an LC-MS sample for analysis, under the conditions described in Example 1. The amino acid extraction system was kept neutral (pH=7) to prevent amino acid denaturation.

[0058] Related chemical reactions:

[0059] MSA's -SO3H attack on the carbonyl carbon of the peptide bond generates free amino acids: protein → amino acid 1 + amino acid 2 + ... amino acid n; R1-CO-NH-R2+H + →R1-COOH+H2N + -R2.

[0060] (2) Fatty acid extraction and detection: The supernatant of the centrifuge tubes was dried using a vacuum centrifuge concentrator (drying for 5-8 min), and 6M NaOH solution (solvent: 75% (v / v) methanol) was added. The mixture was added to a digestion vessel at a ratio of 100 mg soybean powder to 3 mL (w:v). The sample from centrifuge tube 3 was transferred to a sealed glass bottle and heated in a water bath at 100℃ for 4 h. The reagents from centrifuge tube 4 were transferred to a digestion vessel and digested using a microwave digester at 160℃ for 1.5 h (0-10 min, heating from 0℃ to 160℃; 10-80 min, holding at 160℃ for 70 min; 80-90 min, cooling from 160℃ to room temperature). At least three biological replicates were performed to ensure the reliability of the results. After the reaction was complete, a 6M HCl solution was slowly added dropwise to adjust the pH to less than 5 (the pH in this example was between 3 and 5), causing fatty acids to precipitate. The precipitated fatty acids were then filtered and analyzed by LC-MS under the same conditions as in Example 1. The fatty acid extraction system was kept acidic (pH < 5) to facilitate fatty acid precipitation.

[0061] Related chemical reactions:

[0062] NaOH reacts with oils to produce sodium fatty acids, which further react with hydrochloric acid to produce free fatty acids: oil + 3NaOH → 3 sodium fatty acids + glycerol; sodium fatty acids + HCl → free fatty acids + NaCl.

[0063] (3) Test results

[0064] Amino acid detection results: The content of almost all amino acids was higher in microwave-assisted digestion. Figure 3 Therefore, microwave digestion effectively accelerates the hydrolysis of proteins into amino acids, and can significantly increase the throughput of sample pretreatment.

[0065] Fatty acid detection results: The content of all fatty acids (C16:0, C18:0, C18:1, C18:2, C18:3) was higher in microwave-assisted digestion. Figure 4 Therefore, microwave digestion effectively accelerates the hydrolysis of oils into fatty acids, and can significantly increase the throughput of sample pretreatment.

[0066] Example 3: Verification of the process of optimizing the microwave digestion reaction temperature using the method of the present invention, i.e., the final realization of the method for extracting and analyzing total amino acids and fatty acids from soybeans.

[0067] Based on Examples 1 and 2, the microwave digestion-assisted amino acid extraction conditions were optimized: Methanesulfonic acid (MSA) was selected as the hydrolysis medium to accelerate protein hydrolysis while protecting sensitive amino acids (such as tryptophan), thus establishing optimal reaction parameters that balance detection accuracy and throughput (110℃, 40 min; 120℃, 40 min; 130℃, 40 min; 140℃, 40 min; 150℃, 40 min). Simultaneously, the extraction conditions for fatty acids using microwave digestion-assisted NaOH saponification were optimized. Since the saponification reaction temperature is relatively easy to control, the same three temperature gradients as those used for amino acid extraction were selected for the experiments (110℃, 40 min; 130℃, 40 min; 150℃, 40 min).

[0068] A method for simultaneously extracting amino acids and fatty acids from soybeans, the flowchart of which is shown below. Figure 1 As shown, the steps are as follows:

[0069] (1) Amino acid extraction and detection: Prepare 5 centrifuge tubes (centrifuge tubes 1, 2, 3, 4 and 5) containing 100 mg of soybean powder, add 1.5 mL of n-hexane to each, sonicate (sonication at 10℃, vortex for 10 s every 10 min, 3 times for a total of 30 min), centrifuge at 12000×g for 10 min at 4℃, and keep the supernatant for fatty acid extraction. The precipitate in the centrifuge tubes is vacuum dried (vacuum centrifuge concentrator), and 3 mL of 4M methanesulfonic acid solution is added to each tube. Then, 6 μL of 0.2% 3-mercaptopropionic acid solution and 1.5 μg of 0.05% EDTA powder are added, where the 0.2% 3-mercaptopropionic acid solution and 0.05% EDTA powder are used as antioxidants. Transfer to a digestion vessel and digest using a microwave digester. Perform three biological replicates to ensure the reliability of the results. After the reaction was complete, a 6M HCl solution was slowly added dropwise to adjust the pH to around 7. The mixture was then filtered and injected into an LC-MS for detection, under the same conditions as in Example 1.

[0070] (2) Fatty acid extraction and detection: The supernatants from centrifuge tubes 1, 3, and 5 were dried using a vacuum centrifuge concentrator (drying for 5-8 min), and 6M NaOH solution was added. The mixture was added to a digestion vessel at a ratio of 100 mg soybean powder to 3 mL 6M NaOH solution (w:v), and digested using a microwave digester. Three biological replicates were performed to ensure the reliability of the results. After the reaction was completed, the pH was adjusted to less than 5 (the pH in this example was between 3 and 5), and the mixture was allowed to stand for 1-2 min to precipitate fatty acids. The precipitates were filtered and injected into LC-MS for detection, under the same conditions as in Example 1.

[0071] The specific reaction conditions for microwave-assisted hydrolysis are as follows (Table 1).

[0072] Table 1. Conditions for optimizing the microwave digestion reaction temperature in this invention.

[0073]

[0074] (3) Test results

[0075] Experiments optimizing microwave digestion reaction temperature conditions showed that the content of most amino acids was higher at 120℃ and 130℃. However, considering both signal intensity and stability, 120℃ for 40 min was ultimately selected as the reaction condition for microwave-assisted protein hydrolysis. This ensured both the extraction efficiency of amino acids and reduced byproducts generated due to excessively high reaction temperatures. Figures 5-10 Among fatty acids, C16:0 and C18:1 showed higher reaction conditions under digestion conditions of 110℃ for 40 min, while the other fatty acids (C18:0, C18:2, C18:3) showed higher reaction conditions under digestion conditions of 110℃ for 40 min and 130℃ for 40 min with no significant difference. Considering both signal intensity and stability, digestion at 110℃ for 40 min was selected as the reaction condition for microwave-assisted oil hydrolysis. Figure 11 ).

[0076] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A method for simultaneously extracting amino acids and fatty acids from soybeans, characterized in that, Includes the following steps: Soybeans and n-hexane were mixed and then subjected to sonication and centrifugation to obtain supernatant and precipitate. After the supernatant is evaporated to dryness, NaOH solution is added for digestion to obtain the fatty acid; The precipitate, methanesulfonic acid solution, and antioxidant were mixed and digested to obtain the amino acid. The digestion temperature in the system for extracting the fatty acids was 110℃ and the time was 40 min; the digestion temperature in the system for extracting the amino acids was 120℃ and the time was 40 min. The fatty acids include C16:0, C18:0, C18:1, C18:2, and C18:

3.

2. The method according to claim 1, characterized in that, The methanesulfonic acid solution contains 4M methanesulfonic acid; the antioxidant comprises 0.2% by volume 3-mercaptopropionic acid solution and 0.05% by mass EDTA powder.

3. The method according to claim 2, characterized in that, The mass-to-volume ratio of the precipitate, the methanesulfonic acid solution, the 3-mercaptopropionic acid solution, and the EDTA powder is 100 mg: 3 mL: 6 μL: 1.5 μg.

4. The method according to claim 1, characterized in that, The concentration of NaOH in the NaOH solution is 6M; the mass-to-volume ratio of the soybean to the NaOH solution is 100mg:3mL.

5. The method according to claim 1, characterized in that, When extracting the fatty acids, the digestion process further includes adjusting the pH of the digestate to less than 5.

6. The method according to claim 1, characterized in that, When extracting the amino acids, the digestion process further includes adjusting the pH of the digestate to 7.

7. The method according to claim 1, characterized in that, The mass-to-volume ratio of soybean to n-hexane is 100 mg: 1.5 mL; the centrifugation force is 12,000 × g, the time is 10 min, and the temperature is 4 °C.

Images