Method for extracting agilawood essence substance

Abstract

The invention relates to the field of agilawood essence extraction, in particular to an agilawood essence substance extraction method which comprises the steps of raw material pretreatment, subcritical fluid extraction, molecular distillation purification, alcohol extraction and concentration and macroporous adsorption resin purification. According to the method, subcritical low-temperature extraction and molecular distillation technologies are combined, efficient, high-purity and sectional extraction of volatile essential oil and non-volatile essence substances in agilawood under the low-temperature condition is achieved, damage to thermosensitive components is effectively avoided, and no organic solvent is left.

Description

Technical Field

[0001] This invention relates to the field of agarwood extract, specifically to a method for extracting agarwood extract. Background Technology

[0002] Agarwood is a resinous wood secreted by trees of the genus Aquilaria or Gyrinops in the Thymelaeaceae family as a self-repairing agent after natural damage or human destruction. Its fragrance is elegant and mellow, and it is known as the "king of fragrances". It is an extremely precious spice and traditional Chinese medicine, with effects such as promoting qi circulation and relieving pain, warming the stomach and stopping vomiting, and calming asthma.

[0003] Traditional agarwood extraction methods mainly include steam distillation and solvent extraction. Steam distillation is simple to operate, but the extraction temperature is high (usually exceeding 100°C), which may cause some heat-sensitive active ingredients to decompose, the aroma to be distorted, and the oil yield to be low. Solvent extraction (such as ethanol reflux extraction) has a higher extraction rate, but it will dissolve a large amount of impurities such as wax, pigments, and sugars at the same time. The subsequent purification steps are complicated and there is a risk of solvent residue.

[0004] In recent years, supercritical Fluid extraction (SFE) technology has been applied to the extraction of agarwood essential oil. Although this method can be carried out at a lower temperature and avoids thermal damage, it requires high-end equipment and large investment. Furthermore, it has limited extraction efficiency for highly polar active ingredients in agarwood (such as linalool), and the extract still contains a lot of impurities.

[0005] Tetraol and other characteristic sesquiterpenoids of agarwood are key components of its sedative, tranquilizing, and central nervous system depressant effects, and are also important indicators for identifying the authenticity and quality of agarwood.

[0006] Therefore, developing a method that can gently, efficiently, and selectively extract high-value essential substances such as agarwood essential oil and agaritol while preserving their natural aroma and bioactivity to the maximum extent has significant industrial value. Summary of the Invention

[0007] To address the aforementioned technical problems, this invention provides a method for extracting agarwood essence. Includes the following steps: S1. Raw material pretreatment: Grind the agarwood raw material to 40-80 mesh to obtain agarwood powder; S2. Subcritical fluid extraction: The agarwood powder was extracted using 1,1,1,2-tetrafluoroethane as the extraction solvent at 30-50℃ and 4-10 MPa. After recovering the solvent, crude extract I was obtained. S3. Molecular distillation purification: The crude extract I is subjected to molecular distillation at a distillation temperature of 60-90℃ and a vacuum degree of ≤1.0 Pa, and the distillate is collected as refined agarwood essential oil; S4. Ethanol extraction and concentration: The residue after extraction in step S2 is extracted with 70%-95% ethanol solution using ultrasonic-assisted extraction. The extract is filtered and concentrated under reduced pressure to obtain an extract. S5. Purification with macroporous adsorption resin: The extract is dispersed in water and fed onto a macroporous adsorption resin column. It is first eluted with water, then eluted with 50%-70% ethanol solution. The ethanol eluent is collected, concentrated and dried to obtain agarwood essence powder.

[0008] Preferably, in step S2, the extraction time is 60-120 minutes and the flow rate of the extraction solvent is 15-25 L / h.

[0009] Preferably, in step S3, the scraping speed of the molecular distillation is 200-300 rpm.

[0010] Preferably, in step S4, the amount of ethanol solution used is 10-15 times the mass of agarwood residue, the ultrasonic extraction temperature is 50-70℃, the ultrasonic power is 300-500W, and the extraction is performed 2-3 times, each time for 30-60 minutes.

[0011] Preferably, in step S5, the macroporous adsorption resin is AB-8 type resin.

[0012] Preferably, in step S5, the amount of water used for elution is 10-15 column volumes, and the amount of 50%-70% ethanol used for elution is 5-8 column volumes.

[0013] Preferably, in step S5, the flow rate of the ethanol eluent is 2-3 BV / h.

[0014] Preferably, the agarwood essence powder obtained in step S5 contains at least 30% agaritol.

[0015] The technical effects and advantages of this invention are as follows: 1. Highly efficient extraction, maximizing the preservation of active ingredients and natural aroma: This invention uses 1,1,1,2-tetrafluoroethane (R134a) as a subcritical extraction solvent. This solvent has the advantages of being chemically inert, non-toxic, non-flammable, and easily recyclable. Its critical temperature (101.1℃) and critical pressure (4.06 MPa) are relatively low. This invention operates at a low temperature of 30-50℃, far lower than the 100℃ or above of steam distillation. This effectively prevents the heat-sensitive aroma components and active substances (such as agaric tetraol) in agarwood from decomposing, oxidizing, or isomerizing due to high temperatures, thereby perfectly preserving the pure and elegant natural aroma of agarwood and ensuring the integrity of bioactive components.

[0016] 2. Highly selective extraction, high product purity: The polarity of subcritical R134a is very well matched with the volatile essential oil components in agarwood, which can selectively dissolve and extract the aromatic essential oil components while avoiding the dissolution of a large amount of polar or large molecular impurities such as wax, pigments, and sugars. Subsequently, combined with high vacuum molecular distillation technology, the crude extract is purified at extremely low temperatures (60-90℃) and pressures (≤1.0 Pa), which can further separate and remove trace amounts of light and heavy impurities, ultimately yielding refined agarwood essential oil with light color, pure aroma, and extremely high purity.

[0017] 3. Segmented Precise Extraction with High Resource Utilization: This invention features a unique segmented extraction process. First, subcritical extraction is used to obtain volatile essential oils. Then, the residue is subjected to ultrasonic ethanol extraction, specifically targeting highly polar active substances (such as agaric tetraol). This method achieves the "selection of what is needed" and "complete utilization" of different polar and volatile essential substances in agarwood raw materials, greatly improving the comprehensive utilization rate of resources and the added value of products.

[0018] 4. Targeted preparation of high-purity essence: Targeting the characteristic active ingredients of agarwood, precise purification is carried out by macroporous adsorption resin chromatography. Taking advantage of the differences in the adsorption capacity of the resin for different components, water-soluble impurities (such as sugars) are first washed away with water, and then the target product, agaritol, is selectively eluted with a specific concentration of ethanol (50%-70%). Finally, a high-purity essence powder with agaritol content of not less than 30% can be obtained, providing high-quality raw materials for the development of high-end pharmaceuticals and health products.

[0019] 5. Green and safe process with no solvent residue in the product: The R134a solvent used in the subcritical extraction process can be completely recovered, and the ethanol can also be recovered and reused through vacuum concentration. The final product has no organic solvent residue, which is highly safe and in line with the modern green and environmentally friendly production concept. At the same time, this method avoids the use of a large amount of organic solvents in traditional solvent extraction methods, reducing environmental pollution and production costs.

[0020] 6. Mild process conditions, easy to industrialize and promote: Compared with supercritical... Extraction: The subcritical R134a extraction system used in this invention operates at a lower pressure (4-10 MPa), significantly reducing equipment requirements and investment costs. At the same time, it has high extraction efficiency for essential oil components. The entire process is clear, with well-defined parameters, and is stable and controllable, making it very suitable for large-scale industrial production and possessing extremely high market transformation and application value. Attached Figure Description

[0021] Figure 1 This is a process flow diagram of a method for extracting agarwood essence provided in an embodiment of this application. Detailed Implementation

[0022] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. The embodiments of the present invention are given for illustrative and descriptive purposes only, and are not intended to be exhaustive or to limit the invention to the forms disclosed. Many modifications and variations will be apparent to those skilled in the art. The embodiments were chosen and described to better illustrate the principles and practical application of the invention, and to enable those skilled in the art to understand the invention and design various embodiments with various modifications suitable for a particular purpose. Example 1

[0023] Please see Figure 1 This embodiment provides a method for extracting agarwood essence. Example 1

[0024] Take 1000g of domestic Qinan agarwood and crush it through a 60-mesh sieve.

[0025] Agarwood powder was added to the extraction vessel of a subcritical extraction device (model: HL-5L, Hangzhou Huali). Using R134a as solvent, extraction was carried out at 40℃ and 6 MPa with a flow rate of 20 L / h for 90 minutes. After extraction, the solvent was recovered under reduced pressure in the separation vessel to obtain approximately 12.5g of golden-yellow, fragrant crude extract I (essential oil).

[0026] The crude extract I was fed into a molecular distillation apparatus (model: MD-S80, Guangzhou Hanma). The distillation temperature was set to 75℃, the system vacuum was 0.8 Pa, and the scraper rotation speed was 250 rpm. The distillate was collected to obtain 10.8g of refined agarwood essential oil, which has a sweet and cool aroma and is pure without any impurities.

[0027] Remove the agarwood residue after subcritical extraction, add 10L of 80% ethanol solution, and ultrasonically extract for 50 minutes at 60℃ and 400W power. Repeat the extraction twice, combine the extracts, filter, and concentrate under reduced pressure at 55℃ and -0.09 MPa to obtain approximately 150g of extract.

[0028] Disperse the extract in 300 mL of pure water to prepare a loading solution. Load the loading solution into a pre-treated AB-8 macroporous resin column (column volume: 500 mL) at a flow rate of 1.5 BV / h. Elute with 12 BV of pure water and discard the aqueous solution. Then elute with 6 BV of 60% ethanol at a flow rate of 2.5 BV / h and collect this eluent.

[0029] The 60% ethanol eluent was concentrated under reduced pressure at 55°C to a thick paste, and then freeze-dried to obtain 35g of white to off-white agarwood essence powder. The agaritol content was 38.2% as determined by high performance liquid chromatography (HPLC). Example 2

[0030] Take 1000g of Indonesian agarwood and crush it through a 40-mesh sieve.

[0031] Subcritical extraction conditions: solvent R134a, temperature 35℃, pressure 8 MPa, time 120 minutes, solvent flow rate 18 L / h. Approximately 8.2 g of crude extract I (essential oil) was obtained.

[0032] Molecular distillation conditions: temperature 65℃, vacuum degree 0.5 Pa, rotation speed 280 rpm. 7.1g of refined agarwood essential oil was obtained.

[0033] The residue was extracted three times with 15L of 70% ethanol at 55℃ and 350W, for 40 minutes each time. The subsequent concentration, loading, macroporous resin purification (elution with water and 50% ethanol) and freeze-drying steps were the same as in Example 1, finally yielding 28g of agarwood essence powder with a garnettetrol content of 32.5%.

[0034] Comparative example (traditional steam distillation method) 1000g of agarwood from the same batch was crushed and extracted for 6 hours using the steam distillation method specified in the Chinese Pharmacopoeia to obtain about 6.0g of agarwood essential oil. The essential oil was dark in color and had a slight burnt smell. HPLC analysis showed that the content of its characteristic sesquiterpenes was significantly lower than that of the essential oil obtained by the method of this invention, and agarwood tetraol essence could not be obtained at all.

[0035] The above embodiments fully demonstrate the significant advantages of the method of the present invention in terms of extraction efficiency, product quality, and overall benefits.

[0036] Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art and related fields based on the embodiments of the present invention without inventive effort should fall within the scope of protection of the present invention. Structures, devices, and operating methods not specifically described and explained in the present invention, unless otherwise specified or limited, shall be implemented according to conventional means in the art.

Claims

1. A method for extracting agarwood essence, characterized in that, Includes the following steps: S1. Raw material pretreatment: Grind the agarwood raw material to 40-80 mesh to obtain agarwood powder; S2. Subcritical fluid extraction: The agarwood powder was extracted using 1,1,1,2-tetrafluoroethane as the extraction solvent at 30-50℃ and 4-10 MPa. After recovering the solvent, crude extract I was obtained. S3. Molecular distillation purification: The crude extract I is subjected to molecular distillation at a distillation temperature of 60-90℃ and a vacuum degree of ≤1.0 Pa, and the distillate is collected as refined agarwood essential oil; S4. Ethanol extraction and concentration: The residue after extraction in step S2 is extracted with 70%-95% ethanol solution using ultrasonic-assisted extraction. The extract is filtered and concentrated under reduced pressure to obtain an extract. S5. Purification with macroporous adsorption resin: The extract is dispersed in water and fed onto a macroporous adsorption resin column. It is first eluted with water, then eluted with 50%-70% ethanol solution. The ethanol eluent is collected, concentrated and dried to obtain agarwood essence powder.

2. The method for extracting agarwood essence according to claim 1, characterized in that, In step S2, the extraction time is 60-120 minutes, and the flow rate of the extraction solvent is 15-25 L / h.

3. The method for extracting agarwood essence according to claim 1, characterized in that, In step S3, the scraping speed of the molecular distillation is 200-300 rpm.

4. The method for extracting agarwood essence according to claim 1, characterized in that, In step S4, the amount of ethanol solution used is 10-15 times the mass of agarwood residue, the ultrasonic extraction temperature is 50-70℃, the ultrasonic power is 300-500W, and the extraction is performed 2-3 times, each time for 30-60 minutes.

5. The method for extracting agarwood essence according to claim 1, characterized in that, In step S5, the macroporous adsorption resin is AB-8 type resin.

6. A method for extracting agarwood essence according to claim 1 or 5, characterized in that, In step S5, the amount of water used for elution is 10-15 column volumes, and the amount of 50%-70% ethanol used for elution is 5-8 column volumes.

7. The method for extracting agarwood essence according to claim 1, characterized in that, In step S5, the flow rate of the ethanol eluent is 2-3 BV / h.

8. The method for extracting agarwood essence according to claim 1, characterized in that, The agarwood essence powder obtained in step S5 contains no less than 30% agaritol.

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