A method for extracting antioxidant components from ginger

Abstract

The application discloses a method for extracting ginger antioxidant components, which comprises the following steps: preparing a mixed powder by mixing dry ginger and micro-powder silica gel, adding an extraction solvent, and performing ultrasonic extraction to obtain an extraction liquid; performing ultrafiltration treatment on the extraction liquid, collecting the ultrafiltration liquid, and performing rotary evaporation to obtain a concentrated liquid; mixing the concentrated liquid with a mixed solvent, performing centrifugal purification, and performing reduced-pressure drying to obtain oil-like liquid dry ginger antioxidant components. In the application, micro-powder silica gel is added to raw materials, an ethanol solution, glycerol, CTAB and vitamin C are used to prepare an extraction solvent, and in the process of low-temperature ultrasonic extraction, the problem of difficulty in extracting antioxidant components from dry ginger is solved, the transfer rate and yield of 6-gingerol are effectively improved, the transfer rate of 6-gingerol in dry ginger reaches 77.8%, and the yield reaches 43.6%. Then, in the process of purification, an ether and n-hexane are combined to form a purification solvent, and the purity of the product is effectively improved, and the purity of 6-gingerol reaches 98.6%.

Description

Technical Field

[0001] The present invention relates to the technical field of plant component extraction, and particularly relates to a method for extracting antioxidant components from ginger. Background Art

[0002] Ginger is an important medicinal and edible plant with many effects such as antioxidation, antibacterial, and anticancer. Dry ginger, which is made by drying in the sun or at low temperature, has a pungent taste and a hot nature. It has the effects of warming the middle-jiao to dispel cold, restoring yang and promoting blood circulation, and warming the lungs to resolve fluid-retention, and is mainly used to treat abdominal cold pain, vomiting and diarrhea caused by spleen and stomach deficiency-cold, as well as syndromes of yang collapse and cold-fluid asthma cough. It plays an important role in prescriptions such as Lizhong Pills for treating spleen and stomach deficiency-cold, Sini Decoction for treating yang collapse syndrome, and Xiaoqinglong Decoction for treating cold-fluid cough and asthma.

[0003] Gingerol is an active ingredient in ginger, which has a powerful antioxidant effect and helps to scavenge free radicals in the body and slow down cell aging. Gingerol is the general name of gingerol, shogaol, paradol, zingerone, gingerdione, gingerdiol and other spicy substances related to ginger. Gingerol is a mixture, and the contents of its components in gingerol from different sources are different. 6-Gingerol in gingerol, also called 6-gingerol, has a relatively high content in ginger and is one of the main spicy substances, and has biological activities such as anticancer, analgesic, anti-inflammatory and antioxidant effects. The molecular structure of 6-gingerol contains multiple active groups such as phenolic hydroxyl groups, and these groups can react with free radicals in the body such as superoxide anion radical (O2 - ), hydroxyl radical (·OH), hydrogen peroxide (H2O2), etc. by providing hydrogen atoms, reducing the oxidative damage of free radicals to cells and biological macromolecules. In addition, 6-gingerol can chelate metal ions such as iron ion (Fe 3+ ), copper ion (Cu 2+ ), etc. that can act as catalysts, reducing the activity of metal ions, thereby inhibiting the oxidation reaction catalyzed by metal ions and reducing the generation of oxidation products. 6-Gingerol can also enhance the body's own antioxidant defense ability and maintain the redox balance in the body by activating the antioxidant enzyme system in the body, such as superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT), etc. Therefore, 6-gingerol, as a natural antioxidant, can be applied to the fields of food, medicine and health care, and cosmetics.

[0004] 6-Gingerol, a component of gingerol, contains highly reactive phenolic hydroxyl groups. Due to the high water content of fresh ginger, these hydroxyl groups dissociate into hydrogen ions under the influence of water molecules, leading to the oxidation and loss of 6-gingerol. Furthermore, the high water content of fresh ginger makes it difficult to pulverize, and the large amount of water dilutes the extraction solvent, hindering extraction. Therefore, it is necessary to remove a significant amount of water from fresh ginger. Dried ginger, having undergone drying, has a much lower water content than fresh ginger, resulting in a significantly higher content of antioxidants. This allows for a reduction in the use of extraction solvents and minimizes the oxidation loss of 6-gingerol. However, due to cell dehydration and shrinkage, the tissue structure becomes denser, and the cell walls and intracellular substances become more compact. This makes it more difficult for the solvent to penetrate the cells and fully contact and extract the gingerol, increasing the difficulty of extraction. Summary of the Invention

[0005] To address the above problems, the present invention aims to provide a method for extracting antioxidant components from ginger. This method effectively improves the transfer rate and yield of antioxidant components in dried ginger, enhances the stability of the active ingredient 6-gingerol during extraction, effectively inhibits the transformation or degradation of 6-gingerol, and simplifies the purification steps, reducing losses during purification.

[0006] The objective of this invention is achieved through the following technical solution:

[0007] A method for extracting antioxidant components from ginger, characterized by comprising the following steps:

[0008] (1) After drying fresh ginger, mix it with micronized silica gel and pulverize it into a mixed powder;

[0009] (2) Add the mixed powder to the extraction solvent, place it in an ultrasonic extractor for ultrasonic extraction, filter and collect filtrate 1 and filter cake, perform a second ultrasonic extraction on the filter cake, filter and collect filtrate 2, mix filtrate 1 and filtrate 2 to obtain the extract;

[0010] (3) The extract was subjected to ultrafiltration and the ultrafiltrate was collected;

[0011] (4) The ultrafiltrate is rotary evaporated into a concentrated solution;

[0012] (5) Mix the concentrate with the mixed solvent and centrifuge to purify it, then collect the centrifuged liquid;

[0013] (6) The centrifuged liquid was dried under reduced pressure to obtain an oily liquid, which is the antioxidant component of dried ginger, 6-gingerol.

[0014] Further, step (1) involves cleaning the fresh ginger to remove impurities, then cutting it into slices 2-4 mm thick, drying it under a vacuum of -0.05 MPa to -0.08 MPa and a drying temperature of 35-40°C to obtain dried ginger with a moisture content of 1%-4%, then mixing the dried ginger and micronized silica gel at a mass ratio of 100:3-4, pulverizing it through a 60-80 mesh sieve to obtain a mixed powder.

[0015] Further, in step (2), the ultrasonic extraction specifically involves mixing the mixed powder and the extraction solvent at a mass ratio of 1:15~20, with an ultrasonic vacuum of -0.05MPa~-0.08MPa, an ultrasonic temperature of 10~15℃, an ultrasonic frequency of 20~25kHz, and an ultrasonic time of 45~60min. After ultrasonication, the mixture is filtered, and filtrate 1 and filter cake are collected. The filter cake is then subjected to a second ultrasonic extraction, specifically by mixing the filter cake and the extraction solvent at a ratio of 1:10~12, with an ultrasonic vacuum of -0.05MPa~-0.08MPa, an ultrasonic temperature of 10~15℃, an ultrasonic frequency of 20~25kHz, and an ultrasonic time of 30~40min. After ultrasonication, the mixture is filtered, and filtrate 2 is collected. Filtrate 1 and filtrate 2 are then mixed to obtain the extract.

[0016] Further, in step (2), the extraction solvent is obtained by taking an ethanol solution with a volume fraction of 30%~40%, adding glycerol at a stirring speed of 15~20 rpm, continuing to stir for 1~2 min, adding hexadecyltrimethylammonium bromide (CTAB) under continuous stirring, continuing to stir for 3~5 min, adding vitamin C under continuous stirring, and continuing to stir for 5~8 min.

[0017] Furthermore, the ratio of ethanol solution, glycerol, CTAB and vitamin C in the extraction solvent is 100:10~12:2~3:3~5.

[0018] Dried ginger, due to its drying process, has a lower water content than fresh ginger. Its cells shrink from dehydration, resulting in a denser tissue structure and more compact cell walls and intracellular substances. This makes it more difficult for the solvent to penetrate the cells and fully contact gingerol during the extraction of antioxidants, increasing the difficulty of extraction and leading to a lower transfer rate.

[0019] During the low-temperature ultrasonic process, the effective components extracted are ensured to remain unaffected by temperature degradation.

[0020] In this invention, an extraction solvent is prepared using ethanol solution, glycerol, CTAB, and vitamin C. Vitamin C enhances the activity of CTAB, promoting the disruption of raw material cells by ultrasound, thereby increasing the transfer rate of gingerol during the extraction process. The addition of glycerol and ethanol promotes the penetration of ethanol into dried ginger and the adhesion of CTAB to the surface of the raw material, improving the extraction efficiency of gingerol. At the same time, during the extraction process, glycerol forms a continuous water film, protecting the extracted active ingredients and preventing the decomposition and loss of the extracted gingerol active ingredients caused by local overheating generated by ultrasound. Through this trade-off, the extraction efficiency of gingerol is greatly improved.

[0021] High temperatures can cause the loss of gingerol in dried ginger. Since the extraction of gingerol from dried ginger is difficult, vacuum low-pressure ultrasonic cavitation extraction is used to improve the extraction efficiency of gingerol. However, the boiling point of ethanol solution is lowered under vacuum, and local overheating can occur during the ultrasonic process, which makes the extraction process prone to boiling up.

[0022] In this invention, micronized silica gel is added to the raw materials. The silica gel acts as a transport medium within the raw materials, preventing degradation and loss of active ingredients during the pulverization process. During extraction, the micronized silica gel also functions as a transport medium, synergistically improving temperature uniformity in conjunction with the uniform transport of the continuous water film formed by glycerol, thus effectively protecting the stability of the extract. Furthermore, the introduction of micronized silica gel during extraction, besides improving temperature uniformity, also prevents boiling over caused by a decrease in the boiling point of the extraction solvent, thereby increasing the extraction efficiency of gingerol.

[0023] Furthermore, in step (3), the ultrafiltration process is performed using an ultrafiltration membrane with a molecular weight cutoff of 3000 Da, an ultrafiltration pressure of 0.1~0.3 MPa, an ultrafiltration temperature of 30~35℃, and after the ultrafiltration is completed, the ultrafiltrate is collected.

[0024] Furthermore, in step (4), the rotary evaporation is performed with a vacuum of -0.03 to -0.05 MPa, a rotation speed of 150 to 180 rpm, an evaporation temperature of 35°C to 40°C, evaporation of ethanol until the relative density of the liquid at 35°C is 1.05 to 1.08, and adjustment of the solution pH to 7.50 to 7.80 with a 10% sodium bicarbonate solution to obtain a concentrated solution.

[0025] Furthermore, in step (5), centrifugal purification involves placing the concentrate and the purification solvent in a centrifugal extractor at a temperature of 32-38°C, with a flow ratio of 1:3-5 between the concentrate and the purification solvent, and a mixing flow rate of 10-12 L / h for continuous centrifugal purification. After purification, the purification solvent is collected.

[0026] During the purification process, a specific ratio of diethyl ether and n-hexane is used to form the purification solvent. The polarity of the purification solvent is adjusted. Under alkaline conditions, the flow rates of the concentrate and the purification solvent are controlled to effectively dissolve 6-gingerol in the system and remove other impurities from the concentrate, resulting in high-purity 6-gingerol after final purification and concentration.

[0027] Furthermore, in step (6), the vacuum drying involves placing the purified solvent under a vacuum of -0.05MPa to -0.08MPa and a drying temperature of 40 to 45°C for 30 to 36 hours to obtain an oily liquid.

[0028] Most specifically, a method for extracting antioxidant components from ginger is characterized by comprising the following steps:

[0029] (1) Clean the fresh ginger after removing impurities, then cut it into 2-4 mm thick slices, place it in a vacuum drying oven, dry it at a vacuum degree of -0.05 MPa to -0.08 MPa and a drying temperature of 35-40℃ to obtain dried ginger with a moisture content of 1% to 4%, then mix the dried ginger with micro-powdered silica gel at a mass ratio of 100:3-4 and pulverize it, pass it through a 60-80 mesh sieve, and collect the pulverized mixed powder;

[0030] (2) Add the mixed powder to the extraction solvent and place it in a low-temperature ultrasonic extractor for ultrasonic extraction. The ultrasonic extraction is performed twice. The first ultrasonic extraction is performed by mixing the mixed powder and the extraction solvent at a mass ratio of 1:15~20, with an ultrasonic vacuum of -0.05MPa~-0.08MPa, an ultrasonic temperature of 10~15℃, an ultrasonic frequency of 20~25kHz, and an ultrasonic time of 45~60min. After ultrasonic extraction, the mixture is filtered to collect filtrate 1 and filter cake. The filter cake is then subjected to a second ultrasonic extraction. Specifically, the filter cake and the extraction solvent are mixed at a mass ratio of 1:10~12, with an ultrasonic vacuum of -0.05MPa~-0.08MPa, an ultrasonic temperature of 10~15℃, an ultrasonic frequency of 20~25kHz, and an ultrasonic time of 30~40min. After ultrasonic extraction, the mixture is filtered to collect filtrate 2. Filtrate 1 and filtrate 2 are then mixed to obtain the extract.

[0031] The extraction solvent is a 30%–40% volume fraction ethanol solution. Glycerin is added while stirring at 15–20 rpm, and stirring is continued for 1–2 minutes. Then, hexadecyltrimethylammonium bromide (CTAB) is added while stirring is continued for 3–5 minutes. Finally, vitamin C is added while stirring is continued for 5–8 minutes to obtain the extraction solvent. The ratio of the ethanol solution, glycerin, CTAB, and vitamin C is 100:10:2:3.

[0032] (3) Place the extract in an ultrafiltration membrane with a molecular weight cutoff of 3000 Da for ultrafiltration treatment. The ultrafiltration pressure is 0.1~0.3 MPa and the ultrafiltration temperature is 30~35℃. After ultrafiltration is completed, collect the ultrafiltrate.

[0033] (4) Place the ultrafiltrate in a rotary evaporator, set the vacuum degree to -0.03~-0.05MPa, the rotation speed to 150~180rpm, and the evaporation temperature to 35℃~40℃. Remove ethanol by rotary evaporation until the relative density of the liquid at 35℃ is 1.05~1.08. Adjust the pH of the solution to 7.50~7.80 with a 10% sodium bicarbonate solution to obtain a concentrated solution.

[0034] (5) Take the concentrate and the purification solvent and place them in a centrifugal extractor. Control the temperature at 32~38℃, set the two-phase mixing flow rate to 10~12L / h, and the flow ratio of the concentrate and the purification solvent to 1:3~5. Perform continuous centrifugal purification and collect the purified liquid after purification. The purification solvent is composed of diethyl ether and n-hexane in a volume ratio of 1:6~8.

[0035] (6) The purified solution was dried under reduced pressure to obtain an oily liquid, which was placed in a vacuum concentration and drying oven. The vacuum degree was set to -0.05MPa to -0.08MPa, the drying temperature was 40 to 45℃, and the drying time was 30 to 36 hours to obtain an oily liquid, which is the antioxidant component of dried ginger, 6-gingerol.

[0036] The present invention has the following technical effects:

[0037] This invention addresses the challenge of extracting 6-gingerol from dried ginger by adding micronized silica gel and using an extraction solvent prepared from ethanol, glycerol, CTAB, and vitamin C. During low-temperature ultrasonic extraction, the increased density of the ginger's tissue structure, cell walls, and intracellular components, which hinders 6-gingerol extraction, effectively improves the transfer rate and yield of 6-gingerol. The transfer rate of 6-gingerol from dried ginger reaches 77.8%, and the yield reaches 43.6%. Subsequently, the purification process utilizes a combination of diethyl ether and n-hexane as a purification solvent, effectively enhancing the purity of the product, achieving a 6-gingerol purity of 98.6%. Detailed Implementation

[0038] The present invention will be specifically described below through embodiments. It should be noted that the following embodiments are only used to further illustrate the present invention and should not be construed as limiting the scope of protection of the present invention. Those skilled in the art can make some non-essential improvements and adjustments to the present invention based on the above description.

[0039] Example 1

[0040] A method for extracting antioxidant components from ginger, comprising the following steps:

[0041] (1) Clean the fresh ginger after removing impurities, then cut it into 2-4 mm thick slices, place it in a vacuum drying oven, dry it at a vacuum degree of -0.06 MPa and a drying temperature of 38 ℃ to obtain dried ginger with a moisture content of 3%, then mix the dried ginger with micro-powdered silica gel at a mass ratio of 100:3.5 and pulverize it, pass it through an 80-mesh sieve, and collect the pulverized mixed powder;

[0042] (2) Add the mixed powder from step (1) to the extraction solvent and place it in a low-temperature ultrasonic extractor for ultrasonic extraction. The ultrasonic extraction is performed twice. The first ultrasonic extraction is performed by mixing the mixed powder and the extraction solvent at a mass ratio of 1:18, with an ultrasonic vacuum of -0.06 MPa, an ultrasonic temperature of 12 ℃, an ultrasonic frequency of 22 kHz, and an ultrasonic time of 50 min. After ultrasonic extraction, the mixture is filtered, and filtrate 1 and filter cake are collected. The filter cake is then subjected to a second ultrasonic extraction. Specifically, the filter cake and the extraction solvent are mixed at a mass ratio of 1:10, with an ultrasonic vacuum of -0.06 MPa, an ultrasonic temperature of 12 ℃, an ultrasonic frequency of 22 kHz, and an ultrasonic time of 35 min. After ultrasonic extraction, the mixture is filtered, and filtrate 2 is collected. Filtrate 1 and filtrate 2 are mixed to obtain the extract. The ratio of the amount of ethanol solution, glycerol, CTAB and vitamin C is 100:10~12:2~3:3~5.

[0043] The extraction solvent is a 35% ethanol solution. Glycerin is added while stirring at 18 rpm. Stirring is continued for 1 min. Then, hexadecyltrimethylammonium bromide (CTAB) is added while stirring is continued for 4 min. Finally, vitamin C is added while stirring is continued for 6 min to obtain the extraction solvent.

[0044] (3) The extract was placed in an ultrafiltration membrane with a molecular weight cutoff of 3000 Da for ultrafiltration treatment. The ultrafiltration pressure was 0.2 MPa and the ultrafiltration temperature was 32 °C. After ultrafiltration was completed, the ultrafiltrate was collected.

[0045] (4) Place the ultrafiltrate in a rotary evaporator, set the vacuum degree to -0.04MPa, the rotation speed to 160rpm, and the evaporation temperature to 38℃. Remove ethanol by rotary evaporation until the relative density of the liquid at 35℃ is 1.05~1.08. Adjust the pH of the solution to 7.60 with a 10% sodium bicarbonate solution to obtain the concentrated solution.

[0046] (5) Take the concentrate and the purification solvent and place them in a centrifugal extractor. Control the temperature at 35°C, set the two-phase mixing flow rate to 10 L / h, and the flow ratio of the concentrate and the purification solvent to 1:4. Perform continuous centrifugal purification and collect the purified liquid after purification. The purification solvent is composed of diethyl ether and n-hexane in a volume ratio of 1:7.

[0047] (6) The purified solution was dried under reduced pressure to obtain an oily liquid, which was placed in a vacuum concentration and drying oven. The vacuum degree was set to -0.6MPa and the drying temperature was 42℃. After drying for 32 hours, an oily liquid was obtained, which is the antioxidant component of dried ginger, 6-gingerol.

[0048] The formula for calculating the transfer rate is as follows:

[0049]

[0050] The formula for calculating yield is:

[0051]

[0052] In the above formula, the dried raw material is the dried ginger in each embodiment. Calculations show that in Example 1, the transfer rate of 6-gingerol was 77.8%, the yield was 43.6%, and the purity of the final product was 98.6%.

[0053] Comparative Example 1

[0054] The difference compared to Example 1 is that step (1) is as follows:

[0055] Fresh ginger was cleaned and impurities removed, then sliced ​​into 2-4 mm thick slices. The slices were placed in a vacuum drying oven and dried at -0.06 MPa and 38 °C until the moisture content was 3%. The dried ginger was then pulverized and passed through an 80-mesh sieve, and the powder was collected. The remaining steps were the same as in Example 1. That is, Comparative Example 1 did not use micronized silica gel to mix with dried ginger to prepare the powder.

[0056] In step (2) of the extraction process, since there was no micro-powdered silica gel and glycerol water film to form a good transfer medium, obvious boiling occurred during the ultrasonic process.

[0057] Calculations showed that the transfer rate of 6-gingerol in Comparative Example 1 was 62.3%, the yield was 30.3%, and the purity of the final product was 96.2%.

[0058] Comparative Example 2

[0059] Unlike Example 1, the solvent preparation steps in step (2) are as follows:

[0060] Take a 35% ethanol solution, add CTAB while stirring at 18 rpm, continue stirring for 4 min, add vitamin C while stirring for 6 min to obtain the extraction solvent; the remaining steps are the same as in Example 1.

[0061] No glycerol was added to the extraction solvent, and a slight boiling occurred during the extraction process in step (2).

[0062] Because the extraction solvent lacks glycerol, a continuous water film is not formed during extraction to synergistically with the micronized silica gel to create a good transfer medium. This leads to localized overheating during ultrasonic cavitation, resulting in slight boiling. Furthermore, without the protection of the water film, the ultrasonic waves, promoted by the surfactant, damage the structure of the active ingredient 6-gingerol, causing further decomposition and loss. Calculations show that the transfer rate of 6-gingerol in Comparative Example 2 was 57.2%, the yield was 24.5%, and the purity of the final product was 93.7%. While Comparative Example 2 exhibits a high transfer rate of 6-gingerol during extraction, the significant loss of 6-gingerol during the process leads to a substantial decrease in yield and final product purity.

[0063] Comparative Example 3

[0064] Unlike Example 1, the solvent preparation steps in step (2) are as follows:

[0065] Take a 35% (v / v) ethanol solution, add glycerol while stirring at 18 rpm, and continue stirring for 1 min. Then, while continuing stirring, add benzyltriethylammonium chloride (BTEAC) and continue stirring for 4 min. Finally, add vitamin C and continue stirring for 6 min to obtain the extraction solvent. The remaining steps are the same as in Example 1, except that CTAB in Example 1 was replaced with BTEAC.

[0066] Calculations showed that the transfer rate of 6-gingerol in Comparative Example 3 was 71.3%, the yield was 31.7%, and the purity of the final product was 92.4%.

[0067] In Comparative Example 3, the replacement of CTAB with BTEAC resulted in a difference in the effect of the surfactant on solvent polarity. The effect on ultrasonic cavitation was more pronounced than with CTAB, leading to a slight decrease in the transfer rate of 6-gingerol and some damage to 6-gingerol during the process, thus significantly reducing both yield and purity. Using no surfactant as the control group, the calculated transfer rate of 6-gingerol was 50.9%, the yield was 33.4%, and the purity of the finished product was 90.2%. Since CTAB was not added in the control group, it not only failed to improve the ultrasonic cavitation effect, but the water film formed by glycerol actually hindered the disruption of raw material cells by ultrasonic cavitation, thereby reducing the release of 6-gingerol and resulting in a lower transfer rate and ultimately lower extraction efficiency.

[0068] Stability test:

[0069] The other steps are the same as in Example 1. In step (5) centrifugation purification, the total amount of purification solvent remains unchanged. By adjusting the ratio of purification solvent, the change in the purity of the final extract by the purification solvent is observed. The prepared liquid product is placed in a natural light environment at 25°C and 70% relative humidity to observe its stability changes. The results are shown in Table 1.

[0070] Table 1:

[0071]

[0072] It can be seen that the products purified by using diethyl ether, n-hexane, and methanol alone all contain impurities and have low purity. While the purity of the products purified by combining diethyl ether, methanol, and n-hexane in pairs as purification solvents is improved, the yield of the methanol-n-hexane combination is significantly lower than that of the single n-hexane combination, and comparable to that of the single methanol combination. This indicates that improper selection of the combination purification solvent may have a negative impact on the yield and purity of 6-gingerol.

[0073] Furthermore, if the two-phase flow ratio of the concentrate and the purification solvent is not well controlled during the purification process, the final product obtained from purification will not only be affected in terms of yield, but also in terms of purity. However, the products purified by this invention with a two-phase flow ratio of concentrate to purification solvent of 1:3 to 5 have high purity, all above 98%, and the yield is also above 40%.

[0074] Example 2

[0075] A method for extracting antioxidant components from ginger, comprising the following steps:

[0076] (1) Clean the fresh ginger after removing impurities, then cut it into 2-4 mm thick slices, place it in a vacuum drying oven, dry it at a vacuum degree of -0.05 MPa and a drying temperature of 35°C to make dried ginger with a moisture content of 4%, then mix the dried ginger with micro-powdered silica gel at a mass ratio of 100:3 and crush it, pass it through a 60-mesh sieve, and collect the crushed mixed powder.

[0077] (2) Add the mixed powder from step (1) to the extraction solvent and place it in a low-temperature ultrasonic extractor for ultrasonic extraction. The ultrasonic extraction is performed twice. The first ultrasonic extraction is performed by mixing the mixed powder and the extraction solvent at a mass ratio of 1:15, with an ultrasonic vacuum of -0.05MPa, an ultrasonic temperature of 15℃, an ultrasonic frequency of 25kHz, and an ultrasonic time of 45min. After ultrasonic extraction, the mixture is filtered to collect filtrate 1 and filter cake. The filter cake is then subjected to a second ultrasonic extraction. Specifically, the filter cake and the extraction solvent are mixed at a mass ratio of 1:10, with an ultrasonic vacuum of -0.05MPa, an ultrasonic temperature of 15℃, an ultrasonic frequency of 25kHz, and an ultrasonic time of 40min. After ultrasonic extraction, the mixture is filtered to collect filtrate 2. Filtrate 1 and filtrate 2 are mixed to obtain the extract. The ratio of the amount of ethanol solution, glycerol, CTAB and vitamin C is 100:12:3:5.

[0078] The extraction solvent is a 30% ethanol solution. Glycerin is added while stirring at 20 rpm and stirring is continued for 2 minutes. Then, hexadecyltrimethylammonium bromide (CTAB) is added while stirring is continued for 5 minutes. Finally, vitamin C is added while stirring is continued for 8 minutes to obtain the extraction solvent.

[0079] (3) The extract was placed in an ultrafiltration membrane with a molecular weight cutoff of 3000 Da for ultrafiltration treatment. The ultrafiltration pressure was 0.1 MPa and the ultrafiltration temperature was 35 °C. After ultrafiltration was completed, the ultrafiltrate was collected.

[0080] (4) Place the ultrafiltrate in a rotary evaporator, set the vacuum degree to -0.03MPa, the rotation speed to 180rpm, and the evaporation temperature to 35℃. Remove ethanol by rotary evaporation until the relative density of the liquid at 35℃ is 1.05~1.08. Adjust the pH of the solution to 7.80 with a 10% sodium bicarbonate solution to obtain the concentrated solution.

[0081] (5) Take the concentrate and the purification solvent and place them in a centrifugal extractor. Control the temperature at 32°C, set the two-phase mixing flow rate to 10 L / h, and the flow ratio of the concentrate and the purification solvent to 1:3. Perform continuous centrifugal purification and collect the purified liquid after purification. The purification solvent is composed of diethyl ether and n-hexane in a volume ratio of 1:6.

[0082] (6) The purified solution was dried under reduced pressure to obtain an oily liquid, which was placed in a vacuum concentration and drying oven. The vacuum degree was set to -0.05MPa and the drying temperature was 40℃. After drying for 30 hours, an oily liquid was obtained, which is the antioxidant component of dried ginger, 6-gingerol.

[0083] The calculated transfer rate of 6-gingerol in Example 2 was 76.9%, the yield was 42.4%, and the purity of the final product was 98.1%.

[0084] Example 3

[0085] A method for extracting antioxidant components from ginger, comprising the following steps:

[0086] (1) Clean the fresh ginger after removing impurities, then cut it into 2-4 mm thick slices, place it in a vacuum drying oven, dry it at a vacuum degree of -0.08 MPa and a drying temperature of 40℃ to make dried ginger with a moisture content of 1%, then mix the dried ginger with micro-powdered silica gel at a mass ratio of 100:4 and crush it, pass it through an 80-mesh sieve, and collect the crushed mixed powder.

[0087] (2) Add the mixed powder from step (1) to the extraction solvent and place it in a low-temperature ultrasonic extractor for ultrasonic extraction. The ultrasonic extraction is performed twice. The first ultrasonic extraction is performed by mixing the mixed powder and the extraction solvent at a mass ratio of 1:20, with an ultrasonic vacuum of -0.08MPa, an ultrasonic temperature of 10℃, an ultrasonic frequency of 20kHz, and an ultrasonic time of 60min. After ultrasonic extraction, the mixture is filtered to collect filtrate 1 and filter cake. The filter cake is then subjected to a second ultrasonic extraction. Specifically, the filter cake and the extraction solvent are mixed at a mass ratio of 1:12, with an ultrasonic vacuum of -0.08MPa, an ultrasonic temperature of 10℃, an ultrasonic frequency of 20kHz, and an ultrasonic time of 30min. After ultrasonic extraction, the mixture is filtered to collect filtrate 2. Filtrate 1 and filtrate 2 are mixed to obtain the extract. The ratio of the amount of ethanol solution, glycerol, CTAB and vitamin C is 100:11:2.5:4.

[0088] The extraction solvent is a 40% ethanol solution. Glycerin is added while stirring at 15 rpm. Stirring is continued for 1 min. Then, hexadecyltrimethylammonium bromide (CTAB) is added while stirring is continued for 3 min. Finally, vitamin C is added while stirring is continued for 5 min to obtain the extraction solvent.

[0089] (3) The extract was placed in an ultrafiltration membrane with a molecular weight cutoff of 3000 Da for ultrafiltration treatment. The ultrafiltration pressure was 0.3 MPa and the ultrafiltration temperature was 30 °C. After ultrafiltration was completed, the ultrafiltrate was collected.

[0090] (4) Place the ultrafiltrate in a rotary evaporator, set the vacuum degree to -0.05MPa, the rotation speed to 150rpm, and the evaporation temperature to 40℃. Remove ethanol by rotary evaporation until the relative density of the liquid at 35℃ is 1.05~1.08. Adjust the pH of the solution to 7.50 with a 10% sodium bicarbonate solution to obtain the concentrated solution.

[0091] (5) Take the concentrate and the purification solvent and place them in a centrifugal extractor. Control the temperature at 38°C, set the two-phase mixing flow rate to 12L / h, and the flow ratio of the concentrate and the purification solvent to 1:5. Perform continuous centrifugal purification and collect the purified liquid after purification. The purification solvent is composed of diethyl ether and n-hexane in a volume ratio of 1:8.

[0092] (6) The purified solution was dried under reduced pressure to obtain an oily liquid, which was placed in a vacuum concentration and drying oven. The vacuum degree was set to -0.08MPa and the drying temperature was 45℃. After drying for 36 hours, an oily liquid was obtained, which is the antioxidant component of dried ginger, 6-gingerol.

[0093] The calculated transfer rate of 6-gingerol in Example 1 was 77.1%, the yield was 41.5%, and the purity of the final product was 98.2%.

Claims

1. A method for extracting antioxidant components from ginger, characterized in that, Includes the following steps: (1) After drying fresh ginger, mix it with micronized silica gel and pulverize it into a mixed powder; (2) Add the mixed powder to the extraction solvent and place it in an ultrasonic extractor. Perform ultrasonic extraction at a vacuum of -0.05MPa to -0.08MPa and a temperature of 10 to 15℃. After filtration, collect filtrate 1 and filter cake. Perform a second ultrasonic extraction on the filter cake at a vacuum of -0.05MPa to -0.08MPa and a temperature of 10 to 15℃. After filtration, collect filtrate 2. Mix filtrate 1 and filtrate 2 to obtain the extract. The extraction solvent is an ethanol solution with a volume fraction of 30% to 40%. Add glycerol at a stirring speed of 15 to 20 rpm and continue stirring for 1 to 2 minutes. Under continuous stirring, add hexadecyltrimethylammonium bromide and continue stirring for 3 to 5 minutes. Under continuous stirring, add vitamin C and continue stirring for 5 to 8 minutes to obtain the extraction solvent. The ratio of ethanol solution, glycerol, hexadecyltrimethylammonium bromide and vitamin C in the extraction solvent is 100:10 to 12:2 to 3:3 to 5. (3) The extract was subjected to ultrafiltration and the ultrafiltrate was collected; (4) The ultrafiltrate is rotary evaporated into a concentrated solution; (5) Mix the concentrate with the purification solvent and centrifuge to purify it, and collect the centrifuged liquid. The purification solvent is composed of diethyl ether and n-hexane in a volume ratio of 1:6~8. (6) The centrifuged liquid was dried under reduced pressure to obtain an oily liquid, which is the antioxidant component of dried ginger, 6-gingerol.

2. The method for extracting antioxidant components from ginger as described in claim 1, characterized in that: The step (1) involves cleaning the fresh ginger to remove impurities, then cutting it into slices 2-4 mm thick, and drying it under a vacuum of -0.05 MPa to -0.08 MPa and a drying temperature of 35-40°C to obtain dried ginger with a moisture content of 1%-4%. The dried ginger and micronized silica gel are then mixed at a mass ratio of 100:3-4 and pulverized through a 60-80 mesh sieve to obtain a mixed powder.

3. The method for extracting antioxidant components from ginger as described in claim 1 or 2, characterized in that: In step (2), the ultrasonic extraction specifically involves mixing the mixed powder and the extraction solvent at a mass ratio of 1:15~20, using an ultrasonic vacuum of -0.05MPa~-0.08MPa, an ultrasonic temperature of 10~15℃, an ultrasonic frequency of 20~25kHz, and an ultrasonic time of 45~60min. After ultrasonication, the mixture is filtered, and filtrate 1 and filter cake are collected. The filter cake is then subjected to a second ultrasonic extraction, specifically by mixing the filter cake and the extraction solvent at a ratio of 1:10~12, using an ultrasonic vacuum of -0.05MPa~-0.08MPa, an ultrasonic temperature of 10~15℃, an ultrasonic frequency of 20~25kHz, and an ultrasonic time of 30~40min. After ultrasonication, the mixture is filtered, and filtrate 2 is collected. Filtrate 1 and filtrate 2 are then mixed to obtain the extract.

4. The method for extracting antioxidant components from ginger as described in claim 3, characterized in that: In step (3), the ultrafiltration process is performed using an ultrafiltration membrane with a molecular weight cutoff of 3000 Da, an ultrafiltration pressure of 0.1~0.3 MPa, an ultrafiltration temperature of 30~35℃, and after the ultrafiltration is completed, the ultrafiltrate is collected.

5. The method for extracting antioxidant components from ginger as described in claim 4, characterized in that: In step (4), the rotary evaporation is performed with a vacuum of -0.03 to -0.05 MPa, a rotation speed of 150 to 180 rpm, an evaporation temperature of 35°C to 40°C, evaporation of ethanol until the relative density of the liquid at 35°C is 1.05 to 1.08, and adjustment of the solution pH to 7.50 to 7.80 with a 10% sodium bicarbonate solution to obtain a concentrated solution.

6. The method for extracting antioxidant components from ginger as described in claim 5, characterized in that: In step (6), the vacuum drying is carried out at a vacuum of -0.05MPa to -0.08MPa and a drying temperature of 40 to 45℃ for 30 to 36 hours to obtain an oily liquid.

7. A method for extracting antioxidant components from ginger, characterized in that, Includes the following steps: (1) Clean the fresh ginger after removing impurities, then cut it into 2-4 mm thick slices, place it in a vacuum drying oven, dry it at a vacuum degree of -0.05 MPa to -0.08 MPa and a drying temperature of 35-40℃ to make dried ginger with a moisture content of 1% to 4%, then mix the dried ginger with micronized silica gel at a mass ratio of 100:3-4 and pulverize it, pass it through a 60-80 mesh sieve, and collect the pulverized mixed powder; (2) Add the mixed powder to the extraction solvent and place it in a low-temperature ultrasonic extractor for ultrasonic extraction. The ultrasonic extraction is performed twice. The first ultrasonic extraction is performed by mixing the mixed powder and the extraction solvent at a mass ratio of 1:15~20, with an ultrasonic vacuum of -0.05MPa~-0.08MPa, an ultrasonic temperature of 10~15℃, an ultrasonic frequency of 20~25kHz, and an ultrasonic time of 45~60min. After ultrasonic extraction, the mixture is filtered to collect filtrate 1 and filter cake. The filter cake is then subjected to a second ultrasonic extraction. Specifically, the filter cake and the extraction solvent are mixed at a mass ratio of 1:10~12, with an ultrasonic vacuum of -0.05MPa~-0.08MPa, an ultrasonic temperature of 10~15℃, an ultrasonic frequency of 20~25kHz, and an ultrasonic time of 30~40min. After ultrasonic extraction, the mixture is filtered to collect filtrate 2. Filtrate 1 and filtrate 2 are then mixed to obtain the extract. The extraction solvent is a 30%~40% volume fraction ethanol solution. Glycerin is added while stirring at 15~20 rpm, and stirring is continued for 1~2 minutes. Hexadecyltrimethylammonium bromide is added while stirring is continued for 3~5 minutes. Vitamin C is added while stirring is continued for 5~8 minutes to obtain the extraction solvent. The ratio of the amount of ethanol solution, glycerin, hexadecyltrimethylammonium bromide and vitamin C is 100:10~12:2~3:3~5. (3) Place the extract in an ultrafiltration membrane with a molecular weight cutoff of 3000 Da for ultrafiltration treatment. The ultrafiltration pressure is 0.1~0.3 MPa and the ultrafiltration temperature is 30~35℃. After ultrafiltration is completed, collect the ultrafiltrate. (4) Place the ultrafiltrate in a rotary evaporator, set the vacuum degree to -0.03~-0.05MPa, the rotation speed to 150~180rpm, and the evaporation temperature to 35℃~40℃. Remove ethanol by rotary evaporation until the relative density of the liquid at 35℃ is 1.05~1.

08. Adjust the pH of the solution to 7.50~7.80 with a 10% sodium bicarbonate solution to obtain a concentrated solution. (5) Take the concentrate and the purification solvent and place them in a centrifugal extractor. Control the temperature at 32~38℃, set the two-phase mixing flow rate to 10~12L / h, and the flow ratio of the concentrate and the purification solvent to 1:3~5. Perform continuous centrifugal purification and collect the purified liquid after purification. The purification solvent is composed of diethyl ether and n-hexane in a volume ratio of 1:6~8. (6) The purified solution was dried under reduced pressure to obtain an oily liquid, which was placed in a vacuum concentration and drying oven. The vacuum degree was set to -0.05MPa to -0.08MPa, the drying temperature was 40 to 45℃, and the drying time was 30 to 36 hours to obtain an oily liquid, which is the antioxidant component of dried ginger, 6-gingerol.

Images