CN116515559A - A method for extracting agarwood essential oil based on subcritical low-temperature extraction process - Google Patents

Abstract

The invention relates to the technical field of plant extraction, in particular to a method for extracting essential oil based on a subcritical low-temperature extraction process, which comprises the following steps of firstly crushing agarwood into powder; then performing subcritical extraction on agalloch eaglewood powder to obtain crude product of the heavy essential oil; adding the crude product of the heavy essential oil into a molecular distiller for distillation treatment until the crude product of the heavy essential oil is completely collected by a heavy phase collecting tank and a light phase collecting tank, and collecting liquid in the heavy phase collecting tank to obtain the heavy essential oil; the subcritical low-temperature extraction method is combined with the molecular distillation method to extract the agilawood essential oil, and the required agilawood essential oil is obtained by optimizing the operation parameters, so that the operation conditions are simple and mild, the normal-temperature extraction and low-temperature desolventizing are facilitated, the stability of volatile components in the agilawood essential oil is maintained, the loss of the volatile components in the agilawood essential oil is small, the active components of the agilawood essential oil are effectively reserved, the extraction yield of the agilawood essential oil is greatly improved, and the prepared agilawood essential oil is high in purity and good in quality.

Description

A method for extracting agarwood essential oil based on subcritical low-temperature extraction process

Technical field:

The invention relates to the technical field of plant extraction, in particular to a method for extracting agarwood essential oil based on a subcritical low-temperature extraction process.

Background technique:

Agarwood is a resinous heartwood formed from the Agarwood plant in the family Daphneaceae. The agarwood produced in my country is mainly white wood, which is mainly distributed in the southern regions of my country, such as Guangdong, Guangxi, Hainan, Taiwan and other places. It is a major economic tree species. What is unique about agarwood is that a healthy tree does not produce agarwood, but when it is damaged by the outside world, the defense mechanism of the tree is activated to produce a dark brown resin. These resin-rich woods are called agarwood. . Agarwood is a famous aromatic traditional Chinese medicine in China, which has been included in the "Chinese Pharmacopoeia". At the same time, it is also a traditional precious medicinal material in Japan, India and other countries. Agarwood is famous for its unique fragrance, and is known as "the king of all incense, the first of all incense". Agarwood essential oil is a highly valuable essential oil product extracted from agarwood, which is often used in cosmetics and pharmaceutical industries. Modern pharmacology believes that agarwood essential oil has antioxidant, antibacterial, anti-inflammatory, air-purifying, relaxing and calming properties. Essential oils are often used in aromatherapy to treat anxiety, depression, insomnia, and other mental illnesses. Among them, sesquiterpene and 2-(2-phenylethylchromone) are the characteristic components of agarwood essential oil and one of the standards to measure the quality of essential oil.

Today, the extraction methods of agarwood essential oil are becoming more and more abundant. For example, traditional extraction methods: solvent extraction, steam distillation, and some emerging extraction methods: supercritical fluid extraction, biological enzyme-assisted extraction, etc. Among them, the yield of the agarwood essential oil obtained by the steam distillation method is low, and the volatile components in the essential oil are easily damaged during the extraction process, and the loss is relatively large. The solvent extraction method is more destructive to the volatile components of essential oils, and there is a problem of solvent residue, which affects the quality of essential oils. However, the aroma components of the essential oil extracted by supercritical fluid are greatly affected, resulting in a relatively single aroma of the essential oil. Although the components of the agarwood essential oil after biological enzyme-assisted extraction can be greatly preserved, the extraction rate is low, resulting in waste of raw materials, and it is not easy to produce on a large scale. As a new extraction method, subcritical low-temperature extraction is based on the principle that organic matter dissolves similarly. In an anaerobic airtight pressure vessel, during the soaking process of the material and the extractant, the fat-soluble components in the material are transferred to the extractor. In the solvent, after evaporation under reduced pressure, the extractant is separated from the target product, and finally the target product is obtained. This method has the advantages of low extraction temperature, low extraction pressure, low separation temperature, and high extraction efficiency. It has developed rapidly in recent years and achieved the purpose of extracting plant essential oils at lower temperatures, retaining to a large extent The characteristic components of essential oils are widely used in animal and vegetable oils, plant essential oils, plant pigments, Chinese herbal medicines, protein processing and other fields, and are suitable for large-scale production of enterprises. Molecular distillation is a separation method based on the mean free path and volatility difference of molecules of different substances when they are moving, so as to achieve efficient separation. This method is carried out under vacuum conditions, and the operating temperature is far lower than the boiling point. The heating time of the material is short, The advantages of good separation effect and mild conditions for separating products. The crudely extracted essential oil is further purified by molecular distillation, and finally high-purity and high-quality essential oil products are obtained.

At present, the demand for agarwood essential oil in the market is increasing day by day. Since the essential oil contains most of the volatile terpenoids, it is easy to be oxidized and degraded when exposed to light and heat. The extraction rate affects the quality of agarwood essential oil. The extraction rate of agarwood essential oil in the market is generally around 0.8%-5.8%. Therefore, how to improve the extraction rate of agarwood essential oil and keep its characteristic components from damage becomes extremely critical.

Invention content:

The purpose of the present invention is to provide a method for extracting agarwood essential oil based on a subcritical low-temperature extraction process in view of the deficiencies in the prior art. Subcritical low-temperature extraction combined with molecular distillation is used to extract agarwood essential oil, which is conducive to maintaining the volatile components in the agarwood essential oil. The method is stable, greatly improves the extraction yield of agarwood essential oil, and the obtained agarwood essential oil has high purity and good quality.

In order to achieve the above object, the technical scheme adopted in the present invention is:

A method for extracting agarwood essential oil based on a subcritical low-temperature extraction process, comprising the following steps:

A, Agarwood is pulverized into powder;

B. Carrying out subcritical extraction of the agarwood powder to obtain the crude product of the agarwood essential oil;

C. Add the crude agarwood essential oil to a molecular still for distillation until the crude agarwood essential oil is completely collected by the heavy phase collection tank and the light phase collection tank, and collect the liquid in the heavy phase collection tank to obtain the agarwood essential oil.

As a preferred solution, step A specifically includes: crushing the agarwood into powder through a grinder and passing through a 40-80 mesh sieve.

As a preferred solution, step B is specifically:

B1, agarwood powder is added in the extraction device;

B2, turn on the vacuum pump, when the vacuum in the extraction device reaches a certain value, stop the vacuum pump, add a solvent to the extraction device for extraction treatment, and form an extraction mixed oil;

B3. The extracted mixed oil enters the evaporating tank for separation treatment, the solvent is vaporized and separated from the extracted mixed oil, and the extracted mixed oil after the solvent separation is discharged out of the evaporating tank to obtain the crude agarwood essential oil.

As a preferred solution, the crude agarwood essential oil obtained in step B is re-added to the extraction device, and the process of steps B2-B3 is repeated 2-3 times for repeated extraction to obtain a further purified crude agarwood essential oil.

As a preferred solution, in step B3, the solvent is vaporized and separated from the extracted mixed oil, and then returned to the solvent turnover tank after being compressed, liquefied, and condensed in sequence.

As a preferred scheme, the extraction temperature of the subcritical extraction in step B is 35-50° C., and the extraction pressure is 0.3-0.6 Mpa.

As a preferred scheme, the extraction time of subcritical extraction in step B is 1-2h.

As a preferred scheme, in step B3, the solvent is propane, and the ratio of solid to liquid is 1:10-40.

As a priority scheme, during the distillation process in step C, the vacuum degree in the molecular still is controlled to be 2.0 Pa, the first-stage purification temperature is 70-100°C, and the first-stage wiper speed is 180-210r/min. The first-stage collection temperature is 10-25°C, the second-stage purification temperature is 100-130°C, the second-stage wiper speed is 180-210r/min, and the second-stage collection temperature is 10-25°C.

The invention also discloses agarwood essential oil extracted by the above-mentioned method for extracting agarwood essential oil based on a subcritical low-temperature extraction process.

The beneficial effect of the present invention is that: the present invention first crushes the agarwood into powder; then subcritically extracts the agarwood powder to obtain the crude agarwood essential oil; then adds the crude agarwood essential oil into a molecular still for distillation until the crude agarwood It is completely collected by the heavy phase collection tank and the light phase collection tank, and the liquid in the heavy phase collection tank is collected to obtain the agarwood essential oil; the present invention uses a subcritical low temperature extraction method combined with a molecular distillation method to extract the agarwood essential oil, and optimizes the operating parameters To obtain the required agarwood essential oil, the operating conditions are simple and mild, with normal temperature extraction and low temperature precipitation, which is conducive to maintaining the stability of the volatile components in the agarwood essential oil, reducing the loss of the volatile components of the agarwood essential oil, and effectively retaining the activity of the agarwood essential oil ingredients, greatly improving the extraction rate of agarwood essential oil, which can increase the maximum extraction rate of agarwood essential oil to about 25%. Compared with the common extraction methods on the market, the extraction rate is about 3 times higher, which greatly improves the The utilization rate of raw materials, the obtained agarwood essential oil has high purity and good quality, and high-quality agarwood essential oil can be obtained in a short time.

Detailed ways:

The present invention will be further described below in conjunction with preferred embodiments.

Example 1

The method for extracting agarwood essential oil based on the subcritical low-temperature extraction process of the present embodiment, the specific implementation steps are as follows:

(1) Agarwood is crushed into powder by a grinder, passed through a 50-mesh sieve, and set aside.

(2) Carry out subcritical extraction of agarwood powder: take the above-mentioned 10kg agarwood powder and place it in a subcritical low-temperature extraction device; turn on the vacuum pump, and when the vacuum degree in the extraction device reaches -0.085Mpa, stop the vacuum pump; Add propane solvent for extraction treatment, adjust the system temperature to 45°C, the system extraction pressure to 0.5Mpa, the ratio of propane solvent to liquid is 1:30, and the extraction time is 1.5h. After the extraction, collect the extracted mixed oil; the extracted mixed oil enters the evaporation process The tank is subjected to separation treatment, and the solvent is vaporized and separated from the extracted mixed oil, and the extracted mixed oil after the solvent is separated is discharged from the evaporation tank, and the crude agarwood essential oil is collected.

(3) Add the crude agarwood essential oil obtained above into a molecular still, set the vacuum degree in the molecular still to 2.0Pa, the first stage purification temperature is 95°C, the first stage scraping film speed is 200r/min, the second stage The first-stage collection temperature is 20°C; the second-stage purification temperature is 120°C, the second-stage scraping film speed is 200r/min, and the second-stage collection temperature is 20°C; until the crude agarwood essential oil is completely collected by the heavy phase collection tank and the light phase The collection tank is collected, and the agarwood essential oil is collected in the heavy phase collection tank.

Example 2

The method for extracting agarwood essential oil based on the subcritical low-temperature extraction process of the present embodiment, the specific implementation steps are as follows:

(1) Agarwood is crushed into powder by a grinder, passed through a 50-mesh sieve, and set aside.

(2) Take the above-mentioned 10kg agarwood powder, place it in a subcritical low-temperature extraction device, turn on the vacuum pump, and when the vacuum degree in the extraction device reaches -0.085Mpa, stop the vacuum pump, add a propane solvent for extraction treatment, and form an extraction mixed oil. The temperature of the system is 40°C, the extraction pressure of the system is 0.5Mpa, the ratio of propane solvent to liquid is 1:40, and the extraction time is 2h; the extraction mixed oil enters the evaporation tank for separation treatment, and the solvent is separated from the extraction mixed oil after vaporization, and the extraction after separating the solvent The mixed oil is discharged from the evaporating tank to obtain the crude agarwood essential oil; the obtained crude agarwood essential oil is then added to the extraction device, and the extraction is repeated twice to obtain the further purified crude agarwood essential oil.

(3) Add the crude agarwood essential oil obtained above into the molecular still, set the vacuum degree in the molecular still to 2.0Pa, the first stage purification temperature is 85°C, the first stage scraping film speed is 210r/min, the second stage The first-stage collection temperature is 15°C; the second-stage purification temperature is 130°C, the second-stage scraping film speed is 210r/min, and the second-stage collection temperature is 15°C; until the crude agarwood essential oil is completely collected by the heavy phase collection tank and the light phase The collection tank is collected, and the agarwood essential oil is collected in the heavy phase collection tank.

Example 3

The method for extracting agarwood essential oil based on the subcritical low-temperature extraction process of the present embodiment, the specific implementation steps are as follows:

(1) Agarwood is crushed into powder by a grinder, passed through a 50-mesh sieve, and set aside.

(2) Take the above-mentioned 10kg agarwood powder, place it in a subcritical low-temperature extraction device, turn on the vacuum pump, and when the vacuum degree in the extraction device reaches -0.085Mpa, stop the vacuum pump, add a propane solvent for extraction treatment, and form an extraction mixed oil. The temperature of the system is 35°C, the extraction pressure of the system is 0.6Mpa, the ratio of propane solvent to liquid is 1:20, and the extraction time is 2h; the extraction mixed oil enters the evaporation tank for separation treatment, and is separated from the extraction mixed oil after the solvent is vaporized, and the extraction after separating the solvent The mixed oil is discharged from the evaporating tank to obtain the crude agarwood essential oil; the obtained crude agarwood essential oil is then re-introduced into the extraction device, and the extraction is repeated 3 times to obtain a further purified crude agarwood essential oil.

(3) Add the crude agarwood essential oil obtained above into a molecular still, set the vacuum degree in the molecular still to 2.0Pa, the first stage purification temperature is 100°C, the first stage scraping film speed is 190r/min, the second stage The first-stage collection temperature is 25°C; the second-stage purification temperature is 110°C, the second-stage scraping film speed is 190r/min, and the second-stage collection temperature is 25°C; until the crude agarwood essential oil is completely collected by the heavy phase collection tank and the light phase The collection tank is collected, and the agarwood essential oil is collected in the heavy phase collection tank.

Example 4

The method for extracting agarwood essential oil based on the subcritical low-temperature extraction process of the present embodiment, the specific implementation steps are as follows:

(1) Agarwood is crushed into powder by a grinder, passed through a 50-mesh sieve, and set aside.

(2) Take the above-mentioned 10kg agarwood powder, place it in a subcritical low-temperature extraction device, turn on the vacuum pump, and when the vacuum degree in the extraction device reaches -0.085Mpa, stop the vacuum pump, add a propane solvent for extraction treatment, and form an extraction mixed oil. The temperature of the system is 50°C, the extraction pressure of the system is 0.3Mpa, the ratio of propane solvent to liquid is 1:10, and the extraction time is 1h; the extraction mixed oil enters the evaporation tank for separation treatment, and is separated from the extraction mixed oil after the solvent is vaporized, and the extraction after separating the solvent The mixed oil is discharged from the evaporation tank to obtain the crude product of agarwood essential oil.

(3) Add the crude agarwood essential oil prepared above into a molecular still, set the vacuum degree in the molecular still to 6.0Pa, the first stage purification temperature is 70°C, the first stage scraping film speed is 180r/min, the second stage The first-stage collection temperature is 10°C; the second-stage purification temperature is 100°C, the second-stage scraping film speed is 180r/min, and the second-stage collection temperature is 10°C; until the crude agarwood essential oil is completely collected by the heavy phase collection tank and the light phase The collection tank is collected, and the agarwood essential oil is collected in the heavy phase collection tank.

Comparative example 1

Take 10kg of agarwood, crush it into powder, add 150 grams of cellulase (activity 50u/mg), 180 grams of acid amylase (activity 60u/mg) and water, mix well, seal and place at 35-40°C for 20 Day, extraction by steam distillation, heating temperature 110°C, distillation time 8h, 55g of agarwood essential oil was obtained, and the oil yield was 0.55%.

Comparative example 2

Take 10kg of agarwood, crush it into powder, and extract it by simultaneous distillation and extraction, heating at 100°C, and distillation for 8 hours, to obtain fraction 1 (39 grams) of agarwood essential oil. Take out the distilled agarwood powder and carry out supercritical extraction with carbon dioxide as the extraction agent, extraction pressure of 25MPa, extraction temperature of 50°C for 4 hours, separation pressure of 7.5MPa, separation temperature of 55°C, and CO2 flow rate of 210L/h to obtain agarwood Essential oil fraction 2 (55 g). Fraction 1 and Fraction 2 essential oils were mixed, and dried and dehydrated with anhydrous Na ₂ SO ₄ to obtain 86 g of agarwood essential oil with an oil yield of 0.86%.

Comparative example 3

Take 10kg of agarwood, grind it into powder, and extract it by simultaneous distillation and extraction, heating at 95°C, and distillation for 5 hours, to obtain 1.37 grams of agarwood essential oil fraction. Take out the distilled agarwood powder, carry out organic solvent extraction, the extraction reagent is 95% ethanol, heat and reflux extraction 3 times, each time 1.5h, heating temperature 70 ℃, the extract is concentrated to a solid-liquid ratio of 1:1; the extraction reagent is positive Butane, add 2 times the amount of extraction reagent, extract 5 times, each extraction 3h, after the extract is concentrated, 2, 65 grams of agarwood essential oil fractions are obtained. Fraction 1 and Fraction 2 essential oils were mixed, centrifuged and dehydrated, and the rotation speed was set to 5000r/min to obtain agarwood essential oil, 91g, with an oil yield of 0.91%.

Comparative example 4

Take 10kg of agarwood and freeze-dry it, crush it into agarwood powder, the particle size of the agarwood powder is 90 mesh; put the obtained agarwood powder in a container, add cellulase, acid amylase and water to fully mix, seal and place at 40°C Under fermentation for 23 days, the amount of acid amylase added is 1.8% of the raw material of agarwood, the activity is 75u/mg, the amount of cellulase added is 1.5% of the raw material of agarwood, and the activity is 55u/mg; Critical extraction, and then analyze and separate the subcritical fluid. In the subcritical extraction, propane is used as the subcritical fluid extractant, the extraction pressure is 0.7MPa, the extraction temperature is 65°C, and the time is 1.5h; the subcritical fluid after analysis and separation The fluid is subjected to ultrafiltration treatment with an ultrafiltration membrane to obtain agarwood essential oil, with an oil yield of 5.7%.

Experimental test

1. Extraction rate of agarwood essential oil

The agarwood used in the above-mentioned examples 1-4 and comparative examples 1-4 is the same batch of materials, and the extraction yield of the agarwood essential oil extracted in the above-mentioned examples 1-4 and comparative examples 1-4 is calculated as follows Formula to calculate:

Extraction yield=(mass of agarwood essential oil/mass of agarwood powder)*100%;

Record the calculation results in Table 1 below.

Agarwood essential oil extraction yield in each embodiment of table 1, comparative example:

2. GC-MS determination of main components and relative content of agarwood essential oil of this application

As can be seen from Table 1, the method for extracting agarwood essential oil based on a subcritical low-temperature extraction process provided by the present invention has a higher extraction yield of agarwood essential oil, so the method for extracting agarwood essential oil in the present invention has little loss of volatile components of agarwood essential oil, The active ingredients of agarwood essential oil are effectively retained, and the extraction yield of agarwood essential oil is greatly improved. The maximum extraction yield of agarwood essential oil can be increased to about 25%. Compared with common extraction methods on the market, the extraction yield is at least higher About 3 times, which greatly improves the utilization rate of raw materials, and the obtained agarwood essential oil has high purity and good quality.

Of course, the above descriptions are only preferred embodiments of the present invention, so all equivalent changes or modifications made according to the structures, features and principles described in the scope of the patent application of the present invention are included in the scope of the patent application of the present invention.

Claims (10)

1. The method for extracting the heavy essential oil based on the subcritical low-temperature extraction process is characterized by comprising the following steps of:

A. pulverizing lignum Aquilariae Resinatum into powder;

B. subcritical extracting eaglewood powder to obtain crude heavy essential oil;

C. adding the crude product of the heavy essential oil into a molecular distiller for distillation treatment until the crude product of the heavy essential oil is completely collected by a heavy phase collecting tank and a light phase collecting tank, and collecting liquid in the heavy phase collecting tank to obtain the heavy essential oil.

2. The method for extracting the essential oil based on the subcritical low-temperature extraction process according to claim 1, wherein the step A is specifically: pulverizing lignum Aquilariae Resinatum into powder with pulverizer, and sieving with 40-80 mesh sieve.

3. The method for extracting the essential oil based on the subcritical low-temperature extraction process according to claim 1, wherein the step B is specifically:

b1, adding agalloch eaglewood powder into an extraction device;

b2, adding a solvent into the extraction device under a vacuum environment for extraction treatment to form extraction mixed oil;

and B3, separating the extracted mixed oil in an evaporation tank, separating the solvent from the extracted mixed oil after the solvent is evaporated, and discharging the extracted mixed oil after the solvent is separated out of the evaporation tank to obtain crude product of the essential oil.

4. A method for extracting an essential oil based on a subcritical low temperature extraction process according to claim 3, wherein: and B, after the crude agilawood essential oil is obtained in the step B, adding the crude agilawood essential oil into an extraction device again, and repeating the processes of the steps B2-B3 for 2-3 times to perform repeated extraction to obtain the further purified crude agilawood essential oil.

5. A method for extracting an essential oil based on a subcritical low temperature extraction process according to claim 3, wherein: in the step B3, the solvent is separated from the extracted mixed oil after vaporization, and returns to the solvent turnover tank after compression, liquefaction and condensation in sequence.

6. A method for extracting an essential oil based on a subcritical low temperature extraction process according to claim 3, wherein: in the step B3, the solvent is propane, and the feed-liquid ratio is 1:10-40.

7. The method for extracting the essential oil based on the subcritical low-temperature extraction process according to claim 1, wherein the method comprises the following steps of: the extraction temperature of subcritical extraction in step B is 35-50deg.C, and the extraction pressure is 0.3-0.6Mpa.

8. The method for extracting the essential oil based on the subcritical low-temperature extraction process according to claim 1, wherein the method comprises the following steps of: and B, extracting for 1-2h in the subcritical extraction.

9. The method for extracting the essential oil based on the subcritical low-temperature extraction process according to claim 1, wherein the method comprises the following steps of: in the distillation treatment process in the step C, the vacuum degree in the molecular distiller is controlled to be 2.0Pa, the first-stage purification temperature is 70-100 ℃, the first-stage film scraping rotating speed is 180-210r/min, the first-stage collection temperature is 10-25 ℃, the second-stage purification temperature is 100-130 ℃, the second-stage film scraping rotating speed is 180-210r/min, and the second-stage collection temperature is 10-25 ℃.

10. An agilawood essential oil extracted by the subcritical low temperature extraction process-based method of extracting agilawood essential oil according to any one of claims 1-9.