CN114836485B - Method for extracting and isolating ajoene from garlic - Google Patents

Abstract

The invention discloses a method for extracting and separating ajoene from garlic, and belongs to the technical field of intensive processing of agricultural products. The method of the present invention includes the following steps: pretreatment of garlic cloves, pretreatment conditions: vacuum, pressure of more than 400MPa, time of more than 10 minutes; the pretreated garlic cloves are first crushed below -4°C, and then allowed to cool at 100- Enzymatic reaction is carried out under the conditions of 200MPa and 25-35℃ to obtain minced garlic; the minced garlic is extracted with subcritical fluid to obtain garlic oil; the garlic oil is sequentially subjected to molecular distillation and liquid phase purification to obtain ajoene. The present invention first uses ultra-high pressure to passivate alliinase to extract alliin, and then prepares alliinase liquid, and then uses ultra-high pressure to activate alliinase in garlic, which can speed up the enzymatic reaction. , generate more allicin and then generate a higher content of ajoene, and finally obtain a high-yield and high-purity ajoene product through ultra-high pressure regulation, subcritical fluid extraction, molecular distillation, and preparative liquid phase purification.

Description

Method for extracting and isolating ajoene from garlic

Technical field

The invention relates to a method for extracting and separating ajoene from garlic, and belongs to the technical field of intensive processing of agricultural products.

Background technique

Garlic contains alliin and alliinase, but alliin and alliinase exist in the cytoplasm and vacuole respectively, and alliinase cannot act on alliin. When garlic is crushed, alliin is converted into allylsulfenic acid and dehydroalanine under the action of alliinase. Allylsulfenic acid generates allicin through a disproportionation reaction. Allicin is extremely unstable and will It is further decomposed into diallyl sulfide compound, dithiene and ajoene. Therefore, it can be said that ajoene is the second degradation product of alliin. Under natural conditions, the amount of ajoene produced in garlic is very small, and the stability of ajoene is poor. Therefore, the extraction of ajoene is the focus of research.

Chinese patent CN1324142C discloses a defatted garlic extract containing ajoene in which sitosterol and other fat-soluble substances have been removed, as well as its preparation method and application. Chinese patent CN104974068 discloses a method for preparing ajoene. Garlic is crushed, and the extract is added and mixed. After obtaining the product, it is processed, and then filtered and/or centrifuged. The solvent is removed from the obtained product and then vegetable oil is added and mixed. The obtained product The product is added to the adsorbent and then eluted to obtain a high concentration of ajoene product. However, the above two methods have the problems of low preparation rate and low purity of ajoene.

Contents of the invention

The object of the present invention is to overcome the above-mentioned shortcomings of the prior art and provide a method for extracting and separating ajoene from garlic.

In order to achieve the above objects, the present invention adopts the following technical solutions:

A method for extracting and isolating ajoene from garlic includes the following steps:

Pretreatment of garlic cloves, pretreatment conditions: vacuum, pressure of more than 400MPa, time of more than 10 minutes;

The pretreated garlic cloves are first crushed below -4°C, and then subjected to an enzymatic reaction at 100-200MPa and 25-35°C to obtain minced garlic;

Minced garlic is extracted with subcritical fluid to obtain garlic oil;

Garlic oil is subjected to molecular distillation and liquid phase purification in sequence to obtain ajoene.

The present invention finds through experimental research that when ajoene is extracted and separated from garlic, ajoene is unstable, resulting in a low yield of ajoene. The method of the present invention can inactivate alliinase in garlic by pretreating garlic cloves; thus, during the process of crushing garlic cloves and releasing alliin, alliinase will not react with alliin and will not react with alliin. It will cause the loss of ajoene, thereby significantly increasing the yield of ajoene.

The invention first uses ultra-high pressure to passivate alliinase to extract alliin, and then prepares alliinase liquid, and then uses ultra-high pressure to activate alliinase in garlic, which can speed up the enzymatic reaction. , generate more allicin and then generate a higher content of ajoene, and finally obtain a high-purity ajoene product through ultra-high pressure regulation, subcritical fluid extraction, molecular distillation, and preparative liquid phase purification.

The method of the present invention can be used to extract and separate ajoene from garlic, and can also be used to extract ajoene from black garlic.

When pretreating garlic cloves, the pressure reaching 400MPa can inactivate the alliinase in garlic. As the pressure further increases, the alliinase inactivation effect becomes better; however, it does not mean that the greater the pressure, the better the alliinase inactivation effect. Experimental studies have shown that when the pressure exceeds 650MPa, the alliinase passivation effect decreases significantly. Therefore, the present invention limits the pressure condition to 400-600MPa; within this pressure condition range, when the pressure is 500-600, the alliinase passivation effect is better. Specifically, the pressure condition can be 520-550MPa or 550-580MPa.

When pretreating garlic cloves, the alliinase in garlic can be inactivated if the time reaches 10 minutes. As time is further extended, the alliinase inactivation effect becomes better; however, it does not mean that the longer the time, the better the alliinase inactivation effect. Experimental studies have shown that when the time exceeds 35 minutes, the alliinase passivation effect decreases significantly. Therefore, the present invention limits the time to 10-30 minutes, and within this time range, when the time is 15-20 minutes, the alliinase passivation effect is better.

Among them, the alliinase passivation effect is measured by the yield of garlic oil; the higher the yield of garlic oil, the better the alliinase passivation effect.

When the pretreated garlic cloves are crushed, the yield of garlic oil begins to increase significantly when the temperature reaches -4°C; as the temperature decreases, the yield of garlic oil increases; but when the temperature is lower than -20 At ℃, the yield of garlic oil decreased significantly. The possible reason is that in the temperature range of -4°C to -20°C, alliinase can maintain a good passivation state. Alliinase will not be activated during the crushing process and will not react with alliin. , will not cause ajoene loss. When the temperature is higher than -4°C, alliinase cannot maintain a good passivation state. Alliinase will be activated during the crushing process, thereby reacting with alliin, resulting in the loss of ajoene. When the temperature is lower than -20°C, although alliinase can be maintained in a good passivation state, the effect is not ideal and the cost is high. Therefore, the temperature when crushing the pretreated garlic cloves can be limited to -4°C to -20°C.

The temperature of the crushed garlic cloves is raised to 25-35°C and the pressure is raised to 100-200MPa. At this time, the inactive alliinase is activated and combines with the alliin released during the crushing process. The acid reacts rapidly, i.e., it undergoes an enzymatic reaction. Among them, 25-35°C is the activity temperature of alliinase; and the purpose of raising the pressure to 100-200MPa is to activate the passivated alliinase and increase the yield of garlic oil. The possible reason is that this pressure condition can increase the reaction rate of alliinase and alliin, thereby significantly reducing the decomposition loss of ajoene. When the pressure condition is 150-180MPa, the yield of high garlic oil is higher.

The reaction time of the enzymatic reaction is appropriate for complete reaction, that is, the enzymatic reaction of alliinase is complete.

If the pretreated garlic cloves cannot be processed in time, they can be frozen and stored at -4°C for later use. In order to ensure the passivation state of alliinase in the pretreated garlic cloves, the frozen storage temperature can be -4 to -20°C.

The extraction of minced garlic using subcritical fluid to obtain garlic oil means: using butane as the extraction agent, extracting under the conditions of -0.1Mpa and 20-50°C, and then reducing the pressure of the extraction liquid to -0.1Mpa. Separate butane from garlic oil to obtain garlic oil;

The conditions for molecular distillation are: 50-100°C, vacuum degree 30-35Pa, garlic oil dripping speed 1-3 drops/3 seconds,

The liquid phase purification means: dissolving the ajoene fraction collected by molecular distillation with 5-8 times the volume of 50-80% ethanol, filtering and then applying to preparative chromatography, using Innoval ODS-2 as filler, 90-95% ethanol As the eluent, elute at a flow rate of 10-30 mL/min, collect the ajoene separated liquid, and concentrate under reduced pressure at 50-70°C to an oily substance to obtain ajoene.

Other operating steps, conditions and parameters in the subcritical fluid extraction, molecular distillation and liquid phase purification are all existing technologies; they will not be described in detail in the present invention.

The beneficial effects of the present invention are:

For the first time, the present invention adopts ultra-high pressure - subcritical fluid extraction - molecular distillation separation - preparative chromatography purification as the core set of technologies to extract and separate ajoene from garlic, which improves the yield and purity of ajoene. The technology is reasonable and feasible, the process is simple, the solvent has low toxicity, the solvent is easy to recycle, and it can be industrially produced in large quantities, so it has strong practical value.

In the present invention, unless otherwise specified, the % mentioned are all mass percentages.

Description of drawings

Figure 1 is a liquid chromatography chart for measuring the ajoene content of the product of step (4) in the specific embodiment of the present invention;

Figure 2 is a chromatogram for determining the ajoene content of the product of step (5) using liquid chromatography in a specific embodiment of the present invention.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and examples.

The structures, proportions, sizes, etc. shown in the drawings of this specification are only used to coordinate with the content disclosed in the specification and are for the understanding and reading of those familiar with this technology. They are not used to limit the conditions under which the present invention can be implemented. Therefore, It has no technical substantive significance. Any structural modifications, changes in proportions or adjustments in size shall still fall within the scope of the technology disclosed in the present invention as long as it does not affect the effectiveness and purpose of the present invention. within the scope of the content covered. At the same time, terms such as "upper", "lower", "left", "right", "middle" and "one" cited in this specification are only for convenience of description and are not used to limit the scope of this specification. The scope of the invention that can be implemented, and changes or adjustments in their relative relationships, as long as there is no substantial change in the technical content, shall also be regarded as the scope of the invention that can be implemented.

Example 1

A method for extracting and separating ajoene from garlic includes the following steps:

(1) Pretreatment of garlic: Weigh 100g garlic cloves, put them into a special ultra-high pressure bag, vacuum seal them and put them into a pressure chamber. Pretreat them for 10 minutes under a pressure of 500MPa. After completion, take them out and place them at -4 to -20 ℃ environment for use.

(2) Crush the pretreated garlic cloves at a temperature of -4°C to -20°C, then place them into an ultra-high pressure chamber, and perform an enzyme-catalyzed reaction in a pressure chamber with a pressure of 100MPa and a temperature of 25°C for 30 minutes; obtain minced garlic.

(3) Prepare garlic oil by subcritical fluid extraction: weigh 150g of garlic powder and put it into a bag, place it in a subcritical extraction tank, and then vacuum the extraction tank until the vacuum is -0.1Mpa; add butane 600mL, the extraction temperature is 30°C, the time is 120min, and the extraction time is 3 times; after the extraction, introduce the extraction liquid into the separation tank, reduce the pressure to -0.1Mpa, separate the butane from the garlic oil, and obtain 0.82g of garlic oil. The garlic oil extraction rate is 0.55%.

(4) Molecular distillation separation: Put the garlic oil into the constant temperature tank of the molecular distillation device, heat the hot oil machine to 50°C, control the vacuum to 30Pa, and drop at a speed of 1 drop/3 seconds. Start the distillation process and collect the ajoene fraction.

(5) Preparative liquid phase purification: Dissolve the ajoene fraction with 5 times the volume of 50% ethanol, filter and apply to preparative chromatography, using Innoval ODS-2 as the filler, 20% ethyl acetate as the eluent, 15 mL/min Elute at a flow rate, collect the ajoene separated liquid, and concentrate under reduced pressure at 60°C to an oily substance to obtain ajoene. The purity of ajoene is 97.7%.

Example 2

A method for extracting and separating ajoene from garlic includes the following steps:

(1) Pretreatment of garlic: Weigh 150g garlic cloves, put them into a special ultra-high pressure bag, vacuum seal them and put them into a pressure chamber. Pretreat them under 520MPa pressure conditions for 15 minutes. After completion, take them out and place them at -4 to -20 ℃ environment for use.

(2) Crush the pretreated garlic cloves at a temperature of -4°C to -20°C, then place them into an ultra-high pressure chamber, and perform an enzyme-catalyzed reaction in a pressure chamber with a pressure of 100MPa and a temperature of 35°C for 30 minutes; obtain minced garlic.

(3) Prepare garlic oil by subcritical fluid extraction: weigh 200g of garlic powder and put it into a bag, place it in a subcritical extraction tank, and then vacuum the extraction tank until the vacuum degree is -0.1Mpa; add butane 900mL, the extraction temperature is 40°C, the time is 120min, and the extraction is 4 times; after the extraction, introduce the extraction liquid into the separation tank, reduce the pressure to -0.1Mpa, separate the butane from the garlic oil, and obtain 1.28g of garlic oil. The extraction rate of garlic oil is 0.64%.

(4) Molecular distillation separation: Put the garlic oil into the constant temperature tank of the molecular distillation device, heat the hot oil machine to 70°C, control the vacuum to 35Pa, and the dropping speed is 2 drops/3 seconds. Start the distillation process and collect the ajoene fraction;

(5) Preparative liquid phase purification: The ajoene fraction was dissolved in 5 times the volume of 60% ethanol, filtered and then subjected to preparative chromatography, using Innoval ODS-2 as the filler and 20% ethyl acetate as the eluent, at 15 mL/min. Elute at a flow rate, collect the ajoene separated liquid, and concentrate under reduced pressure at 60°C to an oily substance to obtain ajoene. The purity of ajoene is 98.1%.

Example 3

A method for extracting and separating ajoene from garlic includes the following steps:

(1) Pretreatment of garlic: Weigh 150g garlic cloves, put them into a special ultra-high pressure bag, vacuum seal them and put them into a pressure chamber. Pretreat them under 550MPa pressure conditions for 20 minutes. After completion, take them out and place them at -4 to -20 ℃ environment for use.

(2) Crush the pretreated garlic cloves at a temperature of -4°C to -20°C, then place them into an ultra-high pressure chamber, and perform an enzyme-catalyzed reaction in a pressure chamber with a pressure of 180MPa and a temperature of 35°C for 35 minutes; obtain minced garlic.

(3) Prepare garlic oil by subcritical fluid extraction: weigh 200g of garlic powder and put it into a bag, place it in a subcritical extraction tank, and then vacuum the extraction tank until the vacuum degree is -0.1Mpa; add butane 1200mL, the extraction temperature is 50℃, the time is 120min, and the extraction is 4 times; after the extraction, introduce the extraction liquid into the separation tank, reduce the pressure to -0.1Mpa, separate the butane from the garlic oil, and obtain 1.20g of garlic oil. The garlic oil extraction rate is 0.60%.

(4) Molecular distillation separation: Put the garlic oil into the constant temperature tank of the molecular distillation device, heat the hot oil machine to 80°C, control the vacuum to 35Pa, and the dropping speed is 2 drops/3 seconds. Start the distillation process and collect the ajoene fraction;

(5) Preparative liquid phase purification: Dissolve the ajoene fraction with 6 times the volume of 60% ethanol, filter and apply to preparative chromatography, using Innoval ODS-2 as the filler, 20% ethyl acetate as the eluent, 10 mL/min Elute at a flow rate, collect the ajoene separated liquid, and concentrate under reduced pressure at 60°C to an oily substance to obtain ajoene. The purity of ajoene is 98.4%.

Example 4

A method for extracting and separating ajoene from garlic includes the following steps:

(1) Pretreatment of garlic: Weigh 200g of garlic cloves, put them into a special ultra-high pressure bag, vacuum seal them and put them into a pressure chamber. Pretreat them for 20 minutes under a pressure of 580MPa. After completion, take them out and place them at -4°C to - Reserved in -20℃ environment.

(2) Crush the pretreated garlic cloves at a temperature of -4°C to -20°C, then place them into an ultra-high pressure chamber, and perform an enzyme-catalyzed reaction in a pressure chamber with a pressure of 150MPa and a temperature of 40°C for 30 minutes; obtain minced garlic.

(3) Prepare garlic oil by subcritical fluid extraction: weigh 300g of garlic powder and put it into a bag, place it in a subcritical extraction tank, and then vacuum the extraction tank until the vacuum is -0.1Mpa; add butane 2000mL, the extraction temperature is 40°C, the time is 150min, and the extraction time is 4 times; after the extraction, introduce the extraction liquid into the separation tank, reduce the pressure to -0.1Mpa, separate the butane from the garlic oil, and obtain 1.82g of garlic oil. The garlic oil extraction rate is 0.60%.

(4) Molecular distillation separation: Put the garlic oil into the constant temperature tank of the molecular distillation device, heat the hot oil machine to 80°C, control the vacuum to 35Pa, and the dropping speed is 3 drops/3 seconds. Start the distillation process and collect the ajoene fraction;

(5) Preparative liquid phase purification: The ajoene fraction was dissolved in 5 times the volume of 80% ethanol, filtered and then subjected to preparative chromatography, using Flash Slica as the filler, 20% ethyl acetate as the eluent, and a flow rate of 20 mL/min. Carry out elution, collect the ajoene separated liquid, and concentrate under reduced pressure at 60°C to an oily substance to obtain ajoene. The purity of ajoene is 98.8%.

Example 5

A method for extracting and separating ajoene from garlic includes the following steps:

(1) Pretreatment of garlic: Weigh 250g garlic cloves, put them into a special ultra-high pressure bag, vacuum seal them and put them into a pressure chamber. Pretreat them for 30 minutes under a pressure of 600MPa. After completion, take them out and place them at -4 to -20 ℃ environment for use.

(2) Crush the pretreated garlic cloves at a temperature of -4°C to -20°C, then place them into an ultra-high pressure chamber, and perform an enzyme-catalyzed reaction in a pressure chamber with a pressure of 200MPa and a temperature of 35°C for 30 minutes; obtain minced garlic.

(3) Prepare garlic oil by subcritical fluid extraction: weigh 300g of garlic powder and put it into a bag, place it in a subcritical extraction tank, and then vacuum the extraction tank until the vacuum is -0.1Mpa; add butane 2000mL, the extraction temperature is 50°C, the time is 120min, and the extraction is performed 5 times; after the extraction, introduce the extraction liquid into the separation tank, reduce the pressure to -0.1Mpa, separate the butane from the garlic oil, and obtain 1.74g of garlic oil. The extraction rate of garlic oil is 0.58%.

(4) Molecular distillation separation: Put the garlic oil into the constant temperature tank of the molecular distillation device, heat the hot oil machine to 100°C, control the vacuum to 35Pa, and drop at a speed of 1 drop/3 seconds. Start the distillation process and collect the ajoene fraction.

(5) Preparative liquid phase purification: The ajoene fraction was dissolved in 5 times the volume of absolute ethanol, filtered and then subjected to preparative chromatography, using Flash Slica as the filler, 20% ethyl acetate as the eluent, and a flow rate of 30 mL/min. Carry out elution, collect the ajoene separated liquid, and concentrate under reduced pressure at 50°C to an oily substance to obtain ajoene. The purity of ajoene is 99.1%.

Comparative example 1

(1) Pretreatment of garlic: Weigh 100g garlic cloves, put them into a special ultra-high pressure bag, vacuum seal them and put them into a pressure chamber. Pretreat them under 500MPa pressure conditions for 35 minutes. After completion, take them out and place them at -4 to -20 ℃ environment for use.

(2) Crush the pretreated garlic cloves at a temperature of -4°C to -20°C, then place them into an ultra-high pressure chamber, and perform an enzyme-catalyzed reaction in a pressure chamber with a pressure of 100MPa and a temperature of 25°C for 30 minutes; obtain minced garlic.

(3) Prepare garlic oil by subcritical fluid extraction: weigh 150g of garlic powder and put it into a bag, place it in a subcritical extraction tank, and then vacuum the extraction tank until the vacuum is -0.1Mpa; add butane 600mL, the extraction temperature is 30°C, the time is 120min, and the extraction is performed 3 times; after the extraction, introduce the extraction liquid into the separation tank, reduce the pressure to -0.1Mpa, separate the butane from the garlic oil, and obtain 0.60g of garlic oil. The garlic oil extraction rate is 0.40%.

(4) Molecular distillation separation: Put the garlic oil into the constant temperature tank of the molecular distillation device, heat the hot oil machine to 50°C, control the vacuum to 30Pa, and drop at a speed of 1 drop/3 seconds. Start the distillation process and collect the ajoene fraction.

(5) Preparative liquid phase purification: Dissolve the ajoene fraction with 5 times the volume of 50% ethanol, filter and apply to preparative chromatography, using Innoval ODS-2 as the filler, 20% ethyl acetate as the eluent, 15 mL/min Elute at a flow rate, collect the ajoene separated liquid, and concentrate under reduced pressure at 60°C to an oily substance to obtain ajoene. The purity of ajoene is 97.1%.

Comparative example 2

(1) Pretreatment of garlic: Weigh 100g garlic cloves, put them into a special ultra-high pressure bag, vacuum seal them and put them into a pressure chamber. Pretreat them for 10 minutes under a pressure of 650MPa. After completion, take them out and place them at -4 to -20 ℃ environment for use.

(2) Crush the pretreated garlic cloves at a temperature of -4°C to -20°C, then place them into an ultra-high pressure chamber, and perform an enzyme-catalyzed reaction in a pressure chamber with a pressure of 100MPa and a temperature of 25°C for 30 minutes; obtain minced garlic.

(3) Prepare garlic oil by subcritical fluid extraction: weigh 150g of garlic powder and put it into a bag, place it in a subcritical extraction tank, and then vacuum the extraction tank until the vacuum is -0.1Mpa; add butane 600mL, the extraction temperature is 30°C, the time is 120min, and the extraction is performed 3 times; after the extraction is completed, introduce the extraction liquid into the separation tank, reduce the pressure to -0.1Mpa, separate the butane from the garlic oil, and obtain 0.54g of garlic oil. The extraction rate of garlic oil is 0.36%.

(4) Molecular distillation separation: Put the garlic oil into the constant temperature tank of the molecular distillation device, heat the hot oil machine to 50°C, control the vacuum to 30Pa, and drop at a speed of 1 drop/3 seconds. Start the distillation process and collect the ajoene fraction.

(5) Preparative liquid phase purification: Dissolve the ajoene fraction with 5 times the volume of 50% ethanol, filter and apply to preparative chromatography, using Innoval ODS-2 as the filler, 20% ethyl acetate as the eluent, 15 mL/min Elute at a flow rate, collect the ajoene separated liquid, and concentrate under reduced pressure at 60°C to an oily substance to obtain ajoene. The purity of ajoene is 96.8%.

Comparative example 3

(1) Pretreatment of garlic: Weigh 100g garlic cloves, put them into a special ultra-high pressure bag, vacuum seal them and put them into a pressure chamber. Pretreat them for 10 minutes under a pressure of 500MPa. After completion, take them out and place them at -4 to -20 ℃ environment for use.

(2) Crush the pretreated garlic cloves at a temperature of -4°C to -20°C, then place them into an ultra-high pressure chamber, and perform an enzyme-catalyzed reaction in a pressure chamber at normal pressure and temperature of 25°C for 30 minutes; obtain minced garlic.

(3) Prepare garlic oil by subcritical fluid extraction: weigh 150g of garlic powder and put it into a bag, place it in a subcritical extraction tank, and then vacuum the extraction tank until the vacuum is -0.1Mpa; add butane 600mL, the extraction temperature is 30°C, the time is 120min, and the extraction is performed 3 times; after the extraction, introduce the extraction liquid into the separation tank, reduce the pressure to -0.1Mpa, separate the butane from the garlic oil, and obtain 0.53g of garlic oil. The garlic oil extraction rate is 0.35%.

(4) Molecular distillation separation: Put the garlic oil into the constant temperature tank of the molecular distillation device, heat the hot oil machine to 50°C, control the vacuum to 30Pa, and drop at a speed of 1 drop/3 seconds. Start the distillation process and collect the ajoene fraction.

(5) Preparative liquid phase purification: Dissolve the ajoene fraction with 5 times the volume of 50% ethanol, filter and apply to preparative chromatography, using Innoval ODS-2 as the filler, 20% ethyl acetate as the eluent, 15 mL/min Elute at a flow rate, collect the ajoene separated liquid, and concentrate under reduced pressure at 60°C to an oily substance to obtain ajoene. The purity of ajoene is 97.4%.

Comparative example 4

(1) Crush the garlic cloves at a temperature of 0°C, then place them into an ultra-high pressure chamber, and perform an enzyme-catalyzed reaction for 30 minutes in a pressure chamber with a pressure of 100MPa and a temperature of 25°C; obtain minced garlic.

(2) Prepare garlic oil by subcritical fluid extraction: weigh 150g of garlic powder and put it into a bag, place it in a subcritical extraction tank, and then vacuum the extraction tank until the vacuum is -0.1Mpa; add butane 600mL, the extraction temperature is 30°C, the time is 150min, and the extraction is performed 3 times; after the extraction, introduce the extraction liquid into the separation tank, reduce the pressure to -0.1Mpa, separate the butane from the garlic oil, and obtain 0.36g of garlic oil. The extraction rate of garlic oil is 0.24%.

(3) Molecular distillation separation: Put the garlic oil into the constant temperature tank of the molecular distillation device, heat the hot oil machine to 50°C, control the vacuum to 30Pa, and the dropping speed is 1 drop/3 seconds. Start the distillation process and collect the ajoene fraction.

(4) Preparative liquid phase purification: Dissolve the ajoene fraction with 5 times the volume of 50% ethanol, filter and apply to preparative chromatography, using Innoval ODS-2 as the filler, 90% ethanol as the eluent, and a flow rate of 15mL/min Carry out elution, collect the ajoene separated liquid, and concentrate under reduced pressure at 60°C to an oily substance to obtain ajoene. The purity of ajoene is 97.6%.

Although the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, they do not limit the scope of the present invention. Those skilled in the art should understand that based on the technical solutions of the present invention, those skilled in the art do not need to perform creative work. Various modifications or variations that can be made are still within the protection scope of the present invention.

Claims (8)

1. A method for extracting and separating ajoene from garlic, which is characterized by comprising the following steps:

pretreating garlic cloves under the following conditions: vacuum, pressure of 500-600MPa, and time of 10-30 min;

crushing the pretreated garlic cloves at the temperature below-4 ℃ and then carrying out enzymatic reaction under the conditions of 100-200MPa and 25-35 ℃ to obtain the minced garlic;

extracting the minced garlic by subcritical fluid to obtain garlic oil;

molecular distillation and liquid phase purification are sequentially carried out on the garlic oil to obtain ajoene;

the extraction of garlic oil from the minced garlic by subcritical fluid means that: extracting butane as extractant at-0.1 Mpa and 20-50deg.C, and then reducing the pressure of the extractive solution to-0.1 Mpa, separating butane from oleum Bulbus Allii to obtain oleum Bulbus Allii;

the conditions of the molecular distillation are as follows: the dripping speed of the garlic oil is 1-3 drops/3 seconds at 50-100 ℃ and the vacuum degree is 30-35Pa,

the liquid phase purification refers to: dissolving ajoene fraction collected by molecular distillation with 5-8 times of ethanol, filtering, purifying with chromatography, eluting with 20% ethyl acetate as eluent at 10-30mL/min, collecting ajoene separating liquid, and concentrating under reduced pressure at 50-70deg.C to obtain ajoene.

2. The method according to claim 1, wherein the garlic clove is pretreated at a pressure of 520-550MPa.

3. The method according to claim 1, wherein the garlic clove is pretreated at a pressure of 550-580MPa.

4. A method according to any one of claims 1-3, characterized in that the garlic cloves are pre-treated for a period of 15-20min.

5. A method according to any one of claims 1-3, characterized in that the pressure conditions of the enzymatic reaction are 150-180MPa.

6. A method according to any one of claims 1-3, characterized in that the pre-treated garlic cloves are placed below-4 ℃ for use before they are crushed.

7. A method according to any one of claims 1-3, characterized in that the pre-treated garlic cloves are crushed at a temperature of-4 ℃ to-20 ℃.

8. The method according to claim 1, wherein Innoval ODS-2 is used as a filler in the preparative chromatography.