Extraction method and application of avenanthramide
A method enhancing avenanthramide extraction from oats by freezing, grinding, and solvent extraction addresses the low natural content issue, achieving a high yield suitable for health products.
Patent Information
- Application Number
- CN202510457676.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-11
- Publication Date
- 2025-07-15
AI Technical Summary
Oat anthramid is naturally low in oats, making it difficult to exert effective doses that have healthy effects.
After freezing, drying and crushing oat seeds, mixing them with n-hexane to degreas, and then mixing them with ethanol solution to extract oat anthracamide, optimizing process parameters to improve extraction efficiency.
The content of oat anthramid was significantly increased. The content of oat anthramid in the extract was 3.69% to 32.01%, which was 11.63 to 53.18 times that of untreated seeds.
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Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of processing and application of cereal functional components, and particularly relates to a method for extracting avenanthramide and its application. Background Art
[0002] Oats are internationally recognized high-quality cereals. Avenanthramides (Avns), which are unique to oats, have become the focus of research in recent years due to their excellent antioxidant and other bioactive functions. Avenanthramide is an alcohol-soluble compound and a unique phenol only found in oats. Early studies have shown that Avns are related to the reduction of serum lipids, cholesterol levels, and the oxidation of low-density lipoproteins; in human clinical studies and several in vitro cell lines, Avns also show an inhibitory effect on inflammatory responses; Avns also have antioxidant and anti-proliferative effects, which contribute to the prevention or treatment of cancer; there are also studies showing that oats contain a variety of antioxidant molecules, including Avns and other phenolic compounds with structures similar to Avns, and among them, the antioxidant ability of Avns is 10-30 times higher than that of other phenolic compounds, such as caffeic acid or vanillin. It can be seen that Avns have broad application prospects. However, the natural content of Avns in oats is low and is greatly affected by the planting environment and genotype, etc., making it difficult to reach the effective dose for exerting health effects, which has become a major obstacle restricting the research on the health mechanism of natural Avns.
[0003] Based on this, the present invention is proposed. Summary of the Invention
[0004] The purpose of the present invention is to provide a method for extracting avenanthramide and its application, so as to solve the problem that the natural content of Avns in oats in the prior art is low and it is difficult to reach the effective dose for exerting health effects.
[0005] In order to achieve the above-mentioned invention purpose, the present invention provides the following technical solutions:
[0006] The present invention provides a method for extracting avenanthramide, comprising the following steps:
[0007] (1) Cultivate oat seeds at 14-18 °C for 2-7 days, freeze, dry, and pulverize to obtain seed powder;
[0008] (2) Mix the seed powder with n-hexane, stir for 0.5-1.5 h, centrifuge to remove the supernatant, repeat this step until the supernatant is colorless, and take the precipitate and dry it to obtain oat powder;
[0009] (3) Mix the oat powder with an ethanol solution, ultrasonicate for 5-15 min, stir for 1.5-2.5 h, centrifuge to take the supernatant, and dry it to obtain an avenanthramide extract.
[0010] Preferably, in step (1), the temperature of the freezing is -75 to -85°C, and the time of the freezing is 22 to 26 h;
[0011] The drying in step (1) is vacuum freeze-drying, the temperature of the vacuum freeze-drying is -65 to -85°C, and the time of the vacuum freeze-drying is 48 to 72 h.
[0012] Preferably, in step (1), the particle size of the crushing is 58 to 62 mesh.
[0013] Preferably, in step (2), the mass-volume ratio of the seed powder to n-hexane is 1 g: 1 to 3 mL, and the rotation speed of the stirring is 100 to 140 rpm.
[0014] Preferably, in step (2), the rotation speed of the centrifugation is 7500 to 8500 rpm, and the time of the centrifugation is 5 to 15 min.
[0015] Preferably, in step (3), the mass-volume ratio of the oat powder to the ethanol solution is 1 g: 18 to 22 mL;
[0016] The initial concentration of the ethanol solution is 75 to 85%.
[0017] Preferably, in step (3), the power of the ultrasonic wave is 260 to 300 W, and the rotation speed of the stirring is 100 to 140 rpm.
[0018] Preferably, in step (3), the centrifugal force of the centrifugation is 3500 to 4500×g, and the time of the centrifugation is 5 to 15 min.
[0019] The present invention provides an oat anthramide extract prepared by the preparation method described above, and the content of oat anthramide in the oat anthramide extract is 3.69% to 32.01%.
[0020] The present invention provides the use of the oat anthramide extract prepared by the preparation method described above or the oat anthramide extract in the preparation of antioxidant and anti-inflammatory products.
[0021] The present invention has the following technical effects and advantages:
[0022] The present invention provides a method for extracting avenanthramide and its application. By culturing seeds at a certain temperature according to the method of the present invention, the types and contents of avenanthramide in oat seeds can be increased. Freezing can maximize the retention of avenanthramide in seeds and prevent its loss. Then, the seeds are dried, crushed, defatted with n-hexane, and finally, avenanthramide is extracted from them with an ethanol solution to obtain an avenanthramide extract, so that the content of avenanthramide in the avenanthramide extract is 3.69% - 32.01%, which is higher than that in the avenanthramide extract of seeds without treatment, and is 11.63 - 53.18 times that in the avenanthramide extract of seeds without treatment. BRIEF DESCRIPTION OF THE DRAWINGS
[0023] Figure 1 Retention time of avenanthramide in the avenanthramide extract of Example 1;
[0024] Figure 2 Retention time of avenanthramide in the avenanthramide extract of Example 2;
[0025] Figure 3 Retention time of avenanthramide in the avenanthramide extract of Example 3;
[0026] Figure 4 Retention time of avenanthramide in the avenanthramide extract of Example 4;
[0027] Figure 5 Standard curve of standard sample AvnsA;
[0028] Figure 6 Standard curve of standard sample Avns B;
[0029] Figure 7 Standard curve of standard sample Avns C. DETAILED DESCRIPTION OF THE INVENTION
[0030] The present invention provides a method for extracting avenanthramide, which includes the following steps:
[0031] (1) Place oat seeds at 14 - 18 °C for 2 - 7 days, freeze, dry, and crush them to obtain seed powder. The culture temperature is preferably 16 °C, and the culture time is preferably 6 days;
[0032] (2) Mix the seed powder with n-hexane, stir for 0.5 - 1.5 h, centrifuge to remove the supernatant, repeat this step until the supernatant is colorless, and take the precipitate and dry it to obtain oat powder. The stirring time is preferably 1 h;
[0033] (3) Mix the oat powder with an ethanol solution, sonicate for 5 - 15 min, stir for 1.5 - 2.5 h, centrifuge and take the supernatant, then dry to obtain the avenanthramide extract. The preferred sonication time is 10 min, and the preferred stirring time is 2 h.
[0034] In the present invention, in step (1), the temperature of the freezing is -75 to -85 °C, preferably -80 °C, and the time of the freezing is 22 - 26 h, preferably 24 h.
[0035] The drying in step (1) is vacuum freeze-drying. The temperature of the vacuum freeze-drying is -65 to -85 °C, preferably -70 to -80 °C, more preferably -75 °C. The time of the vacuum freeze-drying is 48 - 72 h, preferably 56 - 64 h, more preferably 60 h.
[0036] In the present invention, in step (1), the particle size of the pulverization is 58 - 62 mesh, preferably 60 mesh.
[0037] In the present invention, in step (2), the mass-volume ratio of the seed powder to n-hexane is 1 g : 1 - 3 mL, preferably 1 g : 2 mL. The rotation speed of the stirring is 100 - 140 rpm, preferably 120 rpm.
[0038] In the present invention, in step (2), the rotation speed of the centrifugation is 7500 - 8500 rpm, preferably 8000 rpm, and the time of the centrifugation is 5 - 15 min, preferably 10 min.
[0039] In the present invention, in step (3), the mass-volume ratio of the oat powder to the ethanol solution is 1 g : 18 - 22 mL, preferably 1 g : 20 mL.
[0040] The initial concentration of the ethanol solution is 75 - 85%, preferably 80%.
[0041] In the present invention, in step (3), the power of the sonication is 260 - 300 W, preferably 280 W. The rotation speed of the stirring is 100 - 140 rpm, preferably 120 rpm.
[0042] In the present invention, in step (3), the centrifugal force of the centrifugation is 3500 - 4500 × g, preferably 4000 × g, and the time of the centrifugation is 5 - 15 min, preferably 10 min.
[0043] The present invention provides the avenanthramide extract prepared by the described preparation method. The content of avenanthramide in the avenanthramide extract is 3.69% - 32.01%.
[0044] The present invention provides the application of the avenanthramide extract prepared by the described preparation method or the described avenanthramide extract in the preparation of products with antioxidant and anti-inflammatory effects.
[0045] The technical solutions provided by the present invention will be described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.
[0046] In the embodiments of the present invention, avenanthramide A (AvnsA), avenanthramide B (Avns B), and avenanthramide C (AvnsC) were purchased from Shanghai Yuanye Bio-Technology Co., Ltd., and the oat seeds were Bayou No. 1 and Baiyan No. 2, both provided by the Wulanchabu Academy of Agricultural Sciences.
[0047] Example 1
[0048] Select the broken grains from the Bayou No. 1 oat seeds. Take 100 g of Bayou No. 1 oat seeds, rinse them twice with deionized water, cover them with a rectangular gauze, and place them in a biochemical incubator at 16 °C for germination and cultivation for 3 days. Then store them in a refrigerator at -80 °C for 24 h, and then perform vacuum freeze-drying at -75 °C for 60 h. Crush and pass through a 60-mesh sieve to obtain Bayou No. 1 oat seed powder.
[0049] Mix the Bayou No. 1 oat seed powder with 200 ml of n-hexane, stir with a magnetic stirrer at a speed of 120 rpm for 1 h to obtain a mixed sample, and then centrifuge the mixed sample at a speed of 8000 rpm for 10 min to remove the supernatant. Repeat this step until the supernatant is colorless, and take the precipitate and dry it to obtain oat powder.
[0050] Mix the oat powder with an ethanol solution with an initial concentration of 80% according to a mass-to-volume ratio of 1 g:20 mL. Perform ultrasonic treatment on the mixed solution. The ultrasonic power is 280 W, and the ultrasonic time is 10 min. Then stir the mixed solution with a magnetic stirrer at a speed of 120 rpm for 2 h, centrifuge at a centrifugal force of 4000×g for 10 min, take the supernatant and place it in a rotary evaporation flask, and rotary evaporate to dryness to obtain the avenanthramide extract.
[0051] Example 2
[0052] Select the broken grains from the Bayou No. 1 oat seeds. Take 100 g of Bayou No. 1 oat seeds, rinse them twice with deionized water, cover them with a rectangular gauze, and place them in a biochemical incubator at 15 °C for germination and cultivation for 6 days. Then store them in a refrigerator at -85 °C for 26 h, and then perform vacuum freeze-drying at -75 °C for 52 h. Crush and pass through a 58-mesh sieve to obtain Bayou No. 1 oat seed powder.
[0053] Mix the seeds powder of Yannai No. 1 with 100 ml of n-hexane, stir with a magnetic stirrer at a speed of 130 rpm for 1 h to obtain a mixed sample, then centrifuge the mixed sample at a speed of 8500 rpm for 15 min, remove the supernatant, repeat this step until the supernatant is colorless, and take the precipitate to dry to obtain oat powder.
[0054] Mix the oat powder with an ethanol solution with an initial concentration of 80% according to the mass-to-volume ratio of 1 g: 22 mL, perform ultrasonic treatment on the mixed solution, the power of ultrasonic is 300 W, and the ultrasonic time is 13 min. Then stir the mixed solution with a magnetic stirrer at a speed of 110 rpm for 2 h, centrifuge at a centrifugal force of 4000×g for 10 min, take the supernatant and place it in a rotary evaporation flask, and rotary evaporate to dryness to obtain oat anthramide extract.
[0055] Example 3
[0056] Select the broken grains from the seeds of Oat Baiyan No. 2, take 100 g of Oat Baiyan No. 2 seeds, rinse them twice with deionized water, cover them with a rectangular gauze, put them in a biochemical incubator at 16 °C for germination culture for 3 days, then store them in a refrigerator at -80 °C for 22 h, and then perform vacuum freeze-drying at -75 °C for 60 h, and pulverize and pass through a 60-mesh sieve to obtain the seeds powder of Oat Baiyan No. 2.
[0057] Mix the seeds powder of Oat Baiyan No. 2 with 300 ml of n-hexane, stir with a magnetic stirrer at a speed of 120 rpm for 1 h to obtain a mixed sample, then centrifuge the mixed sample at a speed of 8000 rpm for 10 min, remove the supernatant, repeat this step until the supernatant is colorless, and take the precipitate to dry to obtain oat powder.
[0058] Mix the oat powder with an ethanol solution with an initial concentration of 75% according to the mass-to-volume ratio of 1 g: 20 mL, perform ultrasonic treatment on the mixed solution, the power of ultrasonic is 260 W, and the ultrasonic time is 15 min. Then stir the mixed solution with a magnetic stirrer at a speed of 140 rpm for 1.5 h, centrifuge at a centrifugal force of 4000×g for 10 min, take the supernatant and place it in a rotary evaporation flask, and rotary evaporate to dryness to obtain oat anthramide extract.
[0059] Example 4
[0060] Select the broken grains from the seeds of Oat Baiyan No. 2, take 100 g of Oat Baiyan No. 2 seeds, rinse them twice with deionized water, cover them with a rectangular gauze, put them in a biochemical incubator at 18 °C for germination culture for 6 days, then store them in a refrigerator at -75 °C for 24 h, and then perform vacuum freeze-drying at -80 °C for 52 h, and pulverize and pass through a 60-mesh sieve to obtain the seeds powder of Oat Baiyan No. 2.
[0061] Mix the seeds powder of Oat Baiyan No. 2 with 200 ml of n - hexane, stir the mixture with a magnetic stirrer at a speed of 120 rpm for 0.8 h to obtain a mixed sample, then centrifuge the mixed sample at a speed of 8000 rpm for 10 min, remove the supernatant, repeat this step until the supernatant is colorless, and take the precipitate for drying to obtain oat flour.
[0062] Mix the oat flour with an ethanol solution with an initial concentration of 80% according to the mass - volume ratio of 1 g:20 mL, perform ultrasonic treatment on the mixed solution, the power of ultrasonic treatment is 300 W, and the ultrasonic time is 13 min. Then stir the mixed solution with a magnetic stirrer at a speed of 110 rpm for 2.2 h, centrifuge it at a centrifugal force of 4000×g for 13 min, take the supernatant and place it in a rotary evaporation flask, and rotary evaporate it to dryness to obtain oat anthramide extract.
[0063] Control Example 1
[0064] Select the broken grains from the seeds of Oat Bayou No. 1, take 100 g of Oat Bayou No. 1 seeds, rinse them twice with deionized water, and pulverize them through a 60 - mesh sieve to obtain the seeds powder of Oat Bayou No. 1.
[0065] Mix the seeds powder of Oat Bayou No. 1 with 200 ml of n - hexane, stir the mixture with a magnetic stirrer at a speed of 120 rpm for 1 h to obtain a mixed sample, then centrifuge the mixed sample at a speed of 8000 rpm for 10 min, remove the supernatant, repeat this step until the supernatant is colorless, and take the precipitate for drying to obtain oat flour.
[0066] Mix the oat flour with an ethanol solution with an initial concentration of 80% according to the mass - volume ratio of 1 g:20 mL, perform ultrasonic treatment on the mixed solution, the power of ultrasonic treatment is 280 W, and the ultrasonic time is 10 min. Then stir the mixed solution with a magnetic stirrer at a speed of 120 rpm for 2 h, centrifuge it at a centrifugal force of 4000×g for 10 min, take the supernatant and place it in a rotary evaporation flask, and rotary evaporate it to dryness to obtain oat anthramide extract.
[0067] Control Example 2
[0068] Select the broken grains from the seeds of Oat Baiyan No. 2, take 100 g of Oat Baiyan No. 2 seeds, rinse them twice with deionized water, and pulverize them through a 60 - mesh sieve to obtain the seeds powder of Oat Baiyan No. 2.
[0069] Mix the seeds powder of Oat Baiyan No. 2 with 200 ml of n - hexane, stir the mixture with a magnetic stirrer at a speed of 120 rpm for 0.8 h to obtain a mixed sample, then centrifuge the mixed sample at a speed of 8000 rpm for 10 min, remove the supernatant, repeat this step until the supernatant is colorless, and take the precipitate for drying to obtain oat flour.
[0070] Mix oat flour with an ethanol solution with an initial concentration of 80% at a mass-to-volume ratio of 1 g:20 mL. Ultrasonically treat the mixed solution with a power of 300 W for 13 min. Then stir the mixed solution with a magnetic stirrer at a rotation speed of 110 rpm for 2 h, centrifuge it at a centrifugal force of 4000×g for 13 min, take the supernatant and place it in a rotary evaporation flask, and rotary evaporate it to dryness to obtain oat anthramide extract.
[0071] Experimental Example 1: Detection of the content of oat anthramide extract
[0072] Take 2 g each of standard samples AvnsA, Avns B, Avns C and the oat anthramide extracts of Examples 1-4, dissolve them with chromatographic grade methanol, and then make up the volume to 5 mL to obtain methanol solutions of standard samples Avns A, Avns B, Avns C and the oat anthramide extracts of Examples 1-4 respectively.
[0073] 1. Determination of the types in oat anthramide extract
[0074] Adopt high performance liquid chromatography. The chromatograph is Agilent 1220Infinity LC type liquid chromatograph (18 chromatographic column 150 nm×3.0 mm, 5 μm). The mobile phase consists of mobile phase A (0.1% acetic acid water) and mobile phase B (acetonitrile). The flow rate is 0.8 mL / min. The temperature of the column oven is 30 °C. The detection wavelength is 340 nm. The injection volume is 10 μL. The gradient elution program is: 0-4 min (acetic acid water with a volume fraction of 60%), 4-15 min (acetic acid water with a volume fraction of 60%-20%), 15-18 min (acetic acid water with a volume fraction of 20%), 18-23 min (acetic acid water with a volume fraction of 20%-60%), 23-25 min (acetic acid with a volume fraction of 60%).
[0075] First, determine the retention times of standard samples Avns A, Avns B, Avns C. The results are shown in Table 1.
[0076] Table 1 Retention times of standard samples AvnsA, Avns B, Avns C
[0077] Avns types Retention time / min AvnsA 18.309 AvnsB 19.162 AvnsC 20.225
[0078] According to Table 1, the retention times of the three oat anthramides of standard samples Avns A, Avns B, Avns C are 18.309 min, 19.162 min and 20.225 min respectively. Determine the retention times of oat anthramides in the oat anthramide extracts of Examples 1-4 respectively. The results are as Figures 1 - 4 shown Figure 1Retention time of avenanthramides in the avenanthramide extract of Example 1 Figure 2 Retention time of avenanthramides in the avenanthramide extract of Example 1 Figure 3 Retention time of avenanthramides in the avenanthramide extract of Example 3 Figure 4 Retention time of avenanthramides in the avenanthramide extract of Example 4. The abscissa in the figure represents the retention time (min), and the ordinate represents the milli-absorbance (mAU).
[0079] According to Figures 1 - 4 it can be seen that there are multiple peaks in the avenanthramide extracts of Examples 1 to 4, and the retention times of each peak are different. Comparing the retention times of the standard samples Avns A, Avns B, Avns C and avenanthramides in the avenanthramide extracts of Examples 1 to 4, the results are shown in Table 2.
[0080] Table 2 Types and retention times of avenanthramides in the avenanthramide extracts of Examples 1 to 4
[0081] Grouping Types of Avns Retention time / min Example 1 AvnsA, AvnsC 18.439、20.070 Example 2 AvnsA, AvnsB, AvnsC 18.107、19.236、20.225 Example 3 AvnsB, AvnsC 18.971、20.423 Example 4 AvnsB 19.099
[0082] According to Table 2, the types of avenanthramides in the avenanthramide extract of Example 1 are Avns A and Avns C; the types of avenanthramides in the avenanthramide extract of Example 2 are Avns A, Avns B, and Avns C; the types of avenanthramides in the avenanthramide extract of Example 3 are Avns B and Avns C; the types of avenanthramides in the avenanthramide extract of Example 4 are Avns B.
[0083] The same method was used to determine the types of avenanthramides in the avenanthramide extracts of Comparative Examples 1 to 2. The results showed that the types of avenanthramides in the avenanthramide extract of Comparative Example 1 were Avns A, and the types of avenanthramides in the avenanthramide extract of Comparative Example 2 were Avns B.
[0084] Through comprehensive comparison, it can be seen that the types of avenanthramides in the avenanthramide extracts of Examples 1 to 3 are more than those in Comparative Examples 1 to 2, indicating that the treatment of oat seeds can enrich the types of avenanthramides in oat seeds.
[0085] 2. Content determination in avenanthramide extracts
[0086] First, the peak areas of the standard samples Avns A, Avns B, and Avns C were measured, and the results are shown in Table 3.
[0087] Table 3 Peak areas of the standard samples Avns A, Avns B, and Avns C
[0088] Avns types Peak area / mAU*s AvnsA 2870.57 AvnsB 4649.76 AvnsC 573.28
[0089] As can be seen from Table 3, the peak areas of the three avenanthramides, namely standard samples Avns A, Avns B, and Avns C, are 2870.57 mAU*s, 4649.76 mAU*s, and 573.28 mAU*s respectively. Standard curves of Avns A, Avns B, and Avns C are plotted based on the retention times and peak areas of the standard samples Avns A, Avns B, and Avns C, and the results are as Figures 5 - 7 shown Figure 5 This is the standard curve graph of standard sample AvnsA. Figure 6 This is the standard curve graph of standard sample Avns B. Figure 7 This is the standard curve graph of standard sample Avns C. In the graph, the abscissa represents the concentration of the standard product, and the ordinate represents the peak area (mAU*s) of the peak emergence.
[0090] According to Figures 5 - 7 it can be known that the standard curve of standard sample Avns A is y = 39.781x + 278.38, R 2 = 0.9474; the standard curve of standard sample Avns B is y = 39.991x + 463.27, R 2 = 0.9365; the standard curve of standard sample Avns C is y = 44.83x + 104.34, R 2 = 0.9362.
[0091] The peak areas of different types of avenanthramides in the avenanthramide extracts of Examples 1 to 4 are measured, and the results are shown in Table 4.
[0092] Table 4 Peak areas of different types of avenanthramides in the avenanthramide extracts of Examples 1 to 4
[0093] Grouping Types of Avns Peak area / mAU*s Example 1 AvnsA, AvnsC 486.83、584.02 Example 2 AvnsA, AvnsB, AvnsC 2860.16、447.60、2917.35 Example 3 AvnsB, AvnsC 1026.36、1.07 Example 4 AvnsB 1053.75
[0094] According to Table 4, the peak areas of Avns A and Avns C in the avenanthramide extract of Example 1 were 486.83 mAU*s and 584.02 mAU*s, respectively; the peak areas of Avns A, Avns B, and Avns C in the avenanthramide extract of Example 2 were 2860.16 mAU*s, 447.60 mAU*s, and 2917.35 mAU*s, respectively; the peak area of Avns B in the avenanthramide extract of Example 3 was 1026.36 mAU*s, and the peak area of Avns C was 1.07 mAU*s; the peak area of Avns B in the avenanthramide extract of Example 4 was 1053.75 mAU*s. The peak areas of different types of avenanthramides in the avenanthramide extracts of Examples 1 to 4 were substituted into the standard curves of the corresponding standard samples, and the contents of different types of avenanthramides in the avenanthramide extracts of Examples 1 to 4 were obtained. The results are shown in Table 5.
[0095] Table 5 Contents of Different Types of Avenanthramides in the Avenanthramide Extracts of Examples 1 to 4
[0096]
[0097]
[0098] According to Table 5, the avenanthramide in the avenanthramide extract of Example 1 contained Avns A and Avns C, with contents of 96.3 μg and 53.5 μg, respectively, totaling 149.8 μg, and the content of avenanthramide was 7.49%; the avenanthramide in the avenanthramide extract of Example 2 contained Avns A, Avns B, and Avns C, with contents of 324.5 μg, 1.95 μg, and 313.75 μg, respectively, totaling 640.2 μg, and the content of avenanthramide was 32.01%; the avenanthramide in the avenanthramide extract of Example 3 contained Avns B and Avns C, with contents of 70.4 μg and 11.5 μg, respectively, totaling 81.9 μg, and the content of avenanthramide was 4.1%; the avenanthramide in the avenanthramide extract of Example 4 contained Avns B, with a content of 73.85 μg, and the content of avenanthramide was 3.69%.
[0099] The contents of avenanthramide types in the avenanthramide extracts of Comparative Examples 1 to 2 were determined by the same method. The results showed that the content of Avns A in the avenanthramide extract of Comparative Example 1 was 12.88 μg, and the content of avenanthramide was 0.644%. The content of Avns B in the avenanthramide extract of Comparative Example 2 was 1.54 μg, and the content of avenanthramide was 0.077%.
[0100] Through comprehensive comparison, it is known that the content of avenanthramide in the avenanthramide extract obtained by the extraction method of the solution of the present application is significantly higher than that in the avenanthramide extract from seeds without treatment, being 11.63 to 53.18 times that in the avenanthramide extract from seeds without treatment.
[0101] As can be seen from the above embodiments, the present invention provides a method for extracting avenanthramide and its application. By culturing the seeds at a certain temperature according to the method of the present invention, the types and content of avenanthramide in oat seeds can be increased. Freezing can maximize the retention of avenanthramide in the seeds and prevent its loss. Then, the seeds are dried, crushed, defatted with n-hexane, and finally, the avenanthramide in them is extracted with an ethanol solution to obtain an avenanthramide extract, such that the content of avenanthramide in the avenanthramide extract is 3.69% to 32.01%, higher than that in the avenanthramide extract from seeds without treatment, and being 11.63 to 53.18 times that in the avenanthramide extract from seeds without treatment.
[0102] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.
Claims
1. A method for extracting avenanthramide, characterized in that, It includes the following steps: (1) Place oat seeds at 14 - 18 °C for cultivation for 2 - 7 days, freeze, dry, and pulverize to obtain seed powder; (2) Mix the seed powder with n - hexane, stir for 0.5 - 1.5 h, centrifuge to remove the supernatant, repeat this step until the supernatant is colorless, and take the precipitate and dry it to obtain oat powder; (3) Mix the oat powder with an ethanol solution, ultrasonicate for 5 - 15 min, stir for 1.5 - 2.5 h, centrifuge and take the supernatant, and dry it to obtain avenanthramide extract.
2. The preparation method according to claim 1, characterized in that, In step (1), the temperature of the freezing is - 75 - 85 °C, and the time of the freezing is 22 - 26 h; The drying is vacuum freeze - drying, the temperature of the vacuum freeze - drying is - 65 - 85 °C, and the time of the vacuum freeze - drying is 48 - 72 h.
3. The preparation method according to claim 1, characterized in that, In step (1), the particle size of the pulverization is 58 - 62 mesh.
4. The preparation method according to claim 1, wherein In step (2), the mass - to - volume ratio of the seed powder to n - hexane for mixing is 1 g:1 - 3 mL, and the rotation speed of the stirring is 100 - 140 rpm.
5. The preparation method according to claim 1, wherein In step (2), the rotation speed of the centrifugation is 7500 - 8500 rpm, and the time of the centrifugation is 5 - 15 min.
6. The preparation method according to claim 1, wherein In step (3), the mass - to - volume ratio of the oat powder to the ethanol solution for mixing is 1 g:18 - 22 mL; The initial concentration of the ethanol solution is 75 - 85%.
7. The preparation method according to claim 1, characterized in that, In step (3), the power of the ultrasonication is 260 - 300 W, and the rotation speed of the stirring is 100 - 140 rpm.
8. The preparation method according to claim 1, characterized in that In step (3), the centrifugal force of the centrifugation is 3500 - 4500 × g, and the time of the centrifugation is 5 - 15 min.
9. The avenanthramide extract prepared by the preparation method according to any one of claims 1 to 8, characterized in that, The content of avenanthramide in the avenanthramide extract is 3.69% - 32.01%.
10. Use of the avenanthramide extract prepared by the preparation method according to any one of claims 1 - 8 or the avenanthramide extract according to claim 9 in the preparation of antioxidant and anti - inflammatory products.