Superheated steam distillation extraction separation method for magnolol and honokiol in mangnolia officinalis oil

Abstract

The invention belongs to the technical field of forest chemical industry and natural medicine extraction and separation, and discloses a superheated steam distillation extraction and separation method for magnolol and honokiol in mangnolia officinalis oil. The method comprises the following steps: carrying out superheated steam distillation processing on the cortex magnoliae officinalis oil by taking superheated steam with normal pressure or a pressure of less than 0.2 MPa as a desorption medium, carrying out condensation cooling and oil-water separation on distilled oil-water mixed gas, and carrying out classified collection on fractions according to different boiling ranges, densities or aggregation forms, so as to obtain the cortex magnoliae officinalis oil. The density of the oily liquid light fraction is smaller than that of water, and the density of the viscous oily heavy fraction is larger than that of water; and carrying out centrifugal filtration on the heavy fraction, separating to obtain a white or faint yellow crystalline solid magnolol product with the purity of more than 85%, treating the filtrate by an organic solvent precipitation crystallization method, and separating to obtain a white crystalline solid honokiol product with the purity of more than 85%. The method is low in equipment investment, simple and feasible in process, low in production cost and high in industrialization popularization and application feasibility, and the magnolol and honokiol obtained through separation are light in color and high in purity.

Description

Technical Field

[0001] The invention belongs to the technical field of forest chemical industry and Chinese medicinal material processing, and specifically relates to the processing and utilization of magnolia bark plant, and more specifically to a method for extracting and separating magnolol and honokiol in magnolia bark oil by superheated water vapor distillation. Background Art

[0002] Magnolia officinalis is a tree species with dual-purpose medicinal materials and both economic and ecological benefits. Its bark (including trunk bark, root bark, branch bark), flowers and seeds can all be used as medicine, with the bark being the main one. Magnolia officinalis is the dried bark of Magnolia officinalis. It is pungent and warm in nature, bitter in taste, and belongs to the spleen, stomach, large intestine, and lung meridians. It has the effects of promoting qi and drying dampness, lowering adverse qi and relieving asthma. It can be used clinically to treat spleen and stomach disharmony, abdominal distension, vomiting and other diseases caused by dampness, food accumulation, and qi stagnation.

[0003] Studies have shown that Magnolia officinalis contains a variety of medicinal ingredients such as volatile oils, magnolol, honokiol, alkaloids, steroid compounds, etc. Among them, magnolol and honokiol are its main characteristic active ingredients, which have obvious pharmacological activities on digestion, nerves, cardiovascular and respiratory systems, and have a more obvious effect on glucose and lipid metabolism. It also has anti-inflammatory, analgesic, anti-pathogenic microorganisms, antibacterial, anti-tumor, antioxidant and other effects, and is widely used in medicine, pesticides, daily chemical products and other fields. Extracting and separating magnolol and honokiol from Magnolia officinalis plant tissues has important social and economic significance.

[0004] Magnolia oil is the primary extract of magnolia phenol and honokiol extracted and separated from the Magnolia officinalis plant. It is usually made from Magnolia officinalis bark (root bark, stem bark, branch bark), leaves, etc., and is extracted by solvent (ethanol, methanol, petroleum ether, etc.), supercritical CO2 fluid or subcritical fluid extraction to obtain the extract. The product is obtained by concentration and crystallization, crystal filtration, filtrate desolventization and evaporation, or direct desolventization and evaporation concentration, including crude crystalline product of total magnolia phenol, oily liquid magnolia oil and magnolia officinalis extract. Magnolia oil is enriched with the chemical components of Magnolia plant tissue and has a complex composition. In addition to magnolia phenol and honokiol, it also contains volatile oils (β-cineole, α-cineole, γ-cineole, 4-allylphenol), androst-1,4,6-triene-3,17-dione (or ADT), pigments, dimers of magnolia phenol and honokiol, resinous substances and other ingredients. Among them, the resinous substances are very dark in color, highly lipophilic and highly viscous, which make the crude crystalline product of total magnolia phenol and magnolia oil yellow-brown or dark black, and have an adverse effect on the subsequent isolation and purification of magnolia phenol and honokiol.

[0005] At present, the main separation and purification methods of magnolol and magnolol in traditional magnolia oil are: alkali dissolution and acid precipitation method, strong and weak alkaline solvent extraction method, poly-low eutectic solvent extraction method, polyamide resin column chromatography, silica gel column chromatography, high-performance countercurrent chromatography, macroporous resin adsorption elution method, steam distillation method, vacuum distillation method, molecular distillation method and simple combination or coupling. These methods have problems such as complex operation process, low separation efficiency, large amount of solvent or large environmental pollution. Among them, the alkali dissolution and acid precipitation method uses the weak acidity of phenolic compounds, which can react with alkali and be separated from impurity components by dissolution or extraction. It has the characteristics of good separation effect and high yield, but there are problems such as large amount of wastewater and large environmental pollution. In addition, alkali treatment will cause chemical reaction and loss of androst-1,4,6-triene-3,17-dione in magnolia oil; molecular distillation is only suitable for the purification of materials with a content higher than 95%, and needs to be coupled with vacuum distillation, and vacuum distillation The method requires a very high vacuum degree and has low separation efficiency. In addition, Magnolia oil usually contains more resinous substances with dark color, strong lipophilicity and high viscosity, which are difficult to be initially separated by vacuum distillation. Column chromatography and macroporous resin adsorption elution methods require a large amount of solvent. Conventional steam distillation uses saturated water vapor as the desorption medium for distillation separation, but saturated water vapor has high humidity (low dryness) and low gasification efficiency for high boiling point or non-volatile components. It can only evaporate volatile oil components with low boiling point or high volatility, but it is difficult to evaporate magnolol and magnolol with a boiling point of more than 400°C. Summary of the invention

[0006] The purpose of the present invention is to provide a superheated steam distillation extraction and separation method of magnolol and honokiol in magnolia oil in view of the problems existing in the existing extraction and separation methods and process technologies of magnolia oil. The method uses superheated steam as a distillation and desorption medium to perform steam distillation extraction and processing on magnolia oil. Under the distillation temperature condition of less than 250°C, the volatile oil, magnolol, honokiol and other components in magnolia oil are successively distilled out in the form of oil-water mixed gas, and magnolol and honokiol products with a purity of more than 85% are separated by condensation cooling, oil-water separation, fraction classification collection, centrifugal filtration, crystallization precipitation and the like. The two products can also be further purified by simple methods such as recrystallization. The method is simple to operate, has high separation efficiency, low production cost, and is green and environmentally friendly.

[0007] To achieve the above object, the present invention adopts the following process scheme: A method for extracting and separating magnolol and honokiol from magnolia bark oil by superheated steam distillation, comprising the following process steps: (1) Magnolia officinalis oil is added to a steam distillation kettle equipped with a heating device such as a jacket and a coil, and heated until the material temperature rises to 110°C. Then, superheated water vapor with a pressure of normal pressure or less than 0.2 MPa and a temperature of 150 to 250°C is introduced to perform steam distillation. The heating temperature of the distillation kettle, the temperature and flow rate of the superheated water vapor are regulated to adjust the material temperature rise rate and control the final distillation temperature to be 220 to 250°C, so that the distillation process proceeds smoothly; (2) The distilled oil-water mixed gas is condensed and cooled, and the oil and water are separated. The fractions are collected in different sections or categories according to boiling range, density, and aggregation form to obtain an oily liquid light fraction with a density less than water and a viscous oily heavy fraction with a density greater than water and containing crystals. When the distilled fraction does not increase significantly, the distillation is completed, and the remaining molten material in the distillation kettle is discharged while hot and cooled to room temperature to obtain a dark brown solid resin-like substance. (3) placing the heavy fraction in a centrifugal filter for centrifugal filtration to separate a white or light yellow crystalline solid magnolia ol product and an oily filtrate; adding a non-polar organic solvent such as petroleum ether or cyclohexane to the filtrate to precipitate a crystalline precipitate, and collecting the precipitate by filtration to obtain a white crystalline solid and magnolia ol product.

[0008] In the above-mentioned superheated steam distillation extraction and separation method of magnolia oil, the magnolia oil is a primary extract of magnolia and magnolia from the magnolia plant, which refers to the oily liquid or viscous substance obtained by extracting and separating magnolia bark (root bark, stem bark, branch bark), leaves, etc. from Magnolia bark (root bark, stem bark, branch bark), etc., through the extraction and processing methods such as solvent (water, ethanol, methanol, etc.) extraction, supercritical CO2 fluid or subcritical fluid extraction, etc.

[0009] In the above-mentioned superheated steam distillation extraction and separation method of magnolol and honokiol in magnolia bark oil, the distillation temperature is controlled below 250° C. during the entire distillation process. The first stage distillation temperature is 110-180° C., and the main oily liquid light fraction with a density less than water is distilled out. The second stage distillation temperature is 180-250° C., and the main viscous oily heavy fraction with a density greater than water and containing crystals is distilled out.

[0010] Furthermore, in the above-mentioned superheated steam distillation extraction and separation method of magnolol and honokiol in magnolia bark oil, the centrifugal filtration separation condition is a rotation speed of 1000 to 5000 r•min -1 , time: 5 to 15 minutes.

[0011] The above-mentioned superheated steam distillation extraction and separation method of magnolia oil and honokiol can separate magnolia oil and honokiol products with a purity of more than 85%.

[0012] Furthermore, the separated magnolol and honokiol products can be further purified by simple methods such as recrystallization. For example, by using cyclohexane as a solvent, the separated magnolol and honokiol products are recrystallized and purified to obtain magnolol and honokiol products with a purity of 98%.

[0013] The invention discloses a superheated steam distillation extraction and separation method for magnolol and honokiol in magnolia bark oil. Superheated steam is used to replace saturated water vapor as a distillation desorption medium. The magnolia bark oil is subjected to steam distillation extraction processing under a distillation temperature condition of less than 250°C. Volatile oil, magnolol, honokiol and other components in the magnolia bark oil are successively distilled out in the form of oil-water mixed gas, condensed and cooled, and separated from oil and water. The fractions are collected according to the difference in aggregation form, boiling point or density to obtain a light fraction floating on water and a heavy fraction sinking in water. The light fraction is an oily liquid, the chemical composition of which is mainly magnolia bark volatile oil, and the fraction temperature is 110-180°C; the heavy fraction is a viscous substance, the chemical composition of which is mainly magnolol and honokiol, and the fraction temperature is 180-250°C. The heavy fraction is centrifugally filtered to separate a crystalline product of magnolol with a relative content of more than 85%. A non-polar organic solvent is added to the filtrate to precipitate a crystalline precipitate, which can be filtered and collected to obtain a crystalline product of honokiol with a relative content of more than 85%. The two products can be further purified by simple methods such as recrystallization to obtain magnolol and honokiol products with a purity of 98%.

[0014] Compared with the existing methods for extracting and separating magnolol and honokiol from magnolia bark oil, the method of the present invention has the following advantages: The method of the invention is simple, green, environmentally friendly, safe and efficient, has the advantages of small equipment investment, high extraction rate, high separation efficiency, simple and easy operation, low production cost, easy industrialization and promotion, and the like. The separated magnolol and honokiol products are light in color and high in purity.

[0015] The chemical composition of magnolol and honokiol products obtained by extraction and separation is qualitatively and quantitatively analyzed by gas chromatography-mass spectrometry. A small amount of sample is taken, dissolved with an appropriate amount of ethyl acetate, directly injected, and quantitatively analyzed on a GC-2014C gas chromatograph, and the relative percentage content of each component is calculated by peak area normalization method; chromatographic conditions: DB-5 quartz capillary chromatographic column (30 m×0.25 mm×0.25μm), N2 as carrier gas, FID detector, injection port temperature of 250°C, detector temperature of 250°C, injection volume of 1μL; heating program: initial temperature of 70°C is maintained for 2 min, firstly increased to 100°C at 2°C / min, then increased to 180°C at 8°C / min, and then increased to 240°C at 2°C / min. The qualitative analysis of the samples was carried out on a 8890-5977B gas chromatograph-mass spectrometer; the chromatographic conditions were: Agilent HP-5ms capillary column (30 m × 0.25 mm × 0.25μm), He as carrier gas, vaporizer temperature of 240℃, mass spectrometer interface temperature of 250℃, EI ion source, EI ionization voltage of 70eV, ion source temperature of 230℃, quadrupole temperature of 150℃, and injection volume of 1μL; the heating program was the same as the above-mentioned gas chromatograph; the components were identified by comparing with standards, searching the mass spectrometer NIST20.L library and combining with literature data.

[0016] The purity (chemical composition) of the further purified products of magnolol and honokiol was determined by high performance liquid chromatography (HPLC). A small amount of sample was taken, dissolved in suitable methanol, and directly injected and analyzed on the LC-20AT high performance liquid chromatograph, and the relative percentage content of each component was calculated by peak area normalization method. Chromatographic conditions: The liquid chromatography column was a Supersil ODS2 column (4.6mm×200mm, 5μm) from Dalian Yilite Analytical Instrument Co., Ltd.; the mobile phase was methanol-water (78:22); the flow rate was 1mL / min, the detection wavelength was 294nm, the column temperature was 30℃, and the injection volume was 10μL. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 The present invention is a schematic diagram of the process flow of superheated steam distillation extraction and separation of magnolol and honokiol in magnolia bark oil; Figure 2 This is a physical picture of the magnolol product separated and obtained in Example 7 of the present invention; Figure 3 This is a physical picture of the honokiol product separated and obtained in Example 7 of the present invention; Figure 4 This is a liquid chromatogram of the purified magnolol product obtained in Example 8 of the present invention; Figure 5 This is a liquid chromatogram of the purified product of magnolol obtained in Example 8 of the present invention. DETAILED DESCRIPTION

[0018] The present invention is further described in detail below in conjunction with the examples and drawings. The following description is only for the purpose of explaining the present invention and is not intended to limit its content. The experimental methods used in the following examples are conventional methods unless otherwise specified, and the materials, reagents, etc. used in the following examples are all commercially available unless otherwise specified. Example 1

[0019] A method for extracting and separating magnolol and honokiol from magnolia bark oil by superheated steam distillation, comprising the following process steps: (1) 30.07 g of Magnolia officinalis oil was added to a steam distillation kettle equipped with an oil bath indirect heating device, and heated until the material was heated to 110° C., and then superheated water vapor with a pressure of normal pressure (0.1 MPa), a temperature of 220° C., and a flow rate of 650 g / h was introduced to perform steam distillation. The oil bath heating power was adjusted to control the material heating rate and the final distillation temperature to be 220° C., so that the distillation process was carried out smoothly; (2) The distilled oil-water mixed gas was condensed and cooled, and the oil and water were separated. The distilled fractions were automatically divided into two categories according to the boiling point, density, and aggregation form. 3.42g of oily liquid light fraction with a density less than water and 5.20g of viscous oily heavy fraction with a density greater than water and containing crystals were obtained. When the distilled fraction did not increase significantly, the distillation was terminated. The distillation time was 1.92h. The remaining molten material in the distillation kettle was discharged while hot and cooled to room temperature to obtain a dark brown solid resin-like substance. (3) The heavy fraction was placed in a centrifugal filter and centrifuged at a speed of 1500 r / min for 15 minutes to obtain 0.85 g of a white crystalline solid magnolol product and 4.35 g of an oily filtrate; 6 mL of a non-polar organic solvent, petroleum ether, was added to the filtrate to precipitate a crystal precipitate, which was collected by filtration to obtain 0.65 g of a white crystalline solid magnolol product. GC analysis showed that the purity of magnolol and magnolol products (GC peak area normalization method) were 87.02% and 85.79%, respectively. Example 2

[0020] A method for extracting and separating magnolol and honokiol from magnolia bark oil by superheated steam distillation, comprising the following process steps: (1) 30.32 g of Magnolia officinalis oil was added to a steam distillation kettle equipped with an oil bath indirect heating device, and heated until the material was heated to 110° C., and then superheated steam with a pressure of normal pressure (0.1 MPa), a temperature of 230° C., and a flow rate of 650 g / h was introduced to perform steam distillation. The oil bath heating power was adjusted to control the material heating rate and the final distillation temperature to be 230° C., so that the distillation process was carried out smoothly; (2) The evaporated oil-water mixed gas is condensed and cooled, and the oil and water are separated. The evaporated fraction is automatically divided into two categories according to the boiling point, density, and aggregation form. 3.65g of oily liquid light fraction with a density less than water and 7.76g of viscous oily heavy fraction with a density greater than water and containing crystals are obtained. When the evaporated fraction does not increase significantly, the distillation is terminated. The distillation time is 1.92h. The remaining molten material in the distillation kettle is discharged while hot and cooled to room temperature to obtain a dark brown solid resin-like substance.

[0021] (3) The heavy fraction was placed in a centrifugal filter and centrifuged at a speed of 2000 r / min for 10 minutes to obtain 1.37 g of white crystalline solid magnolol product and 6.39 g of oily filtrate; 8 mL of non-polar organic solvent petroleum ether was added to the filtrate to precipitate crystals, which were collected by filtration to obtain 0.95 g of white crystalline solid magnolol product. GC analysis showed that the purity of magnolol and magnolol products (GC peak area normalization method) were 86.37% and 86.52%, respectively. Example 3

[0022] A method for extracting and separating magnolol and honokiol from magnolia bark oil by superheated steam distillation, comprising the following process steps: (1) 30.02 g of Magnolia officinalis oil was added to a steam distillation kettle equipped with an oil bath indirect heating device, and heated until the material was heated to 110° C., and then superheated steam with a pressure of normal pressure (0.1 MPa), a temperature of 240° C., and a flow rate of 600 g / h was introduced to perform steam distillation. The oil bath heating power was adjusted to control the material heating rate and the final distillation temperature to be 240° C., so that the distillation process was carried out smoothly; (2) The evaporated oil-water mixed gas was condensed and cooled, and the oil and water were separated. The evaporated fractions were automatically divided into two categories according to their boiling point, density, and aggregation form. 3.32g of oily liquid light fraction with a density less than water and 8.41g of viscous oily heavy fraction with a density greater than water and containing crystals were obtained. When there was no obvious increase in the evaporated fraction, the distillation was terminated. The distillation time was 1.93h. The remaining molten material in the distillation kettle was discharged while hot and cooled to room temperature to obtain a dark brown solid resin-like substance.

[0023] (3) The heavy fraction was placed in a centrifugal filter and centrifuged at a speed of 2500 r / min for 10 minutes to obtain 1.71 g of white crystalline solid magnolol product and 6.70 g of oily filtrate; 10 mL of non-polar organic solvent petroleum ether was added to the filtrate to precipitate crystals, which were collected by filtration to obtain 1.00 g of white crystalline solid magnolol product. GC analysis showed that the purity of magnolol and magnolol products (GC peak area normalization method) were 87.81% and 86.42%, respectively. Example 4

[0024] A method for extracting and separating magnolol and honokiol from magnolia bark oil by superheated steam distillation, comprising the following process steps: (1) 29.95 g of Magnolia officinalis oil was added to a steam distillation kettle equipped with an oil bath indirect heating device, and heated until the material was heated to 110° C., and then superheated steam with a pressure of normal pressure (0.1 MPa), a temperature of 230° C., and a flow rate of 980 g / h was introduced to perform steam distillation. The oil bath heating power was adjusted to control the material heating rate and the final distillation temperature to be 230° C., so that the distillation process was carried out smoothly; (2) The evaporated oil-water mixed gas is condensed and cooled, and the oil and water are separated. The evaporated fraction is automatically divided into two categories according to the boiling point, density, and aggregation form. The light fraction of oily liquid with a density less than water is 2.45g, and the heavy fraction of viscous oil with a density greater than water and containing crystals is 8.17g. When the evaporated fraction does not increase significantly, the distillation is terminated. The distillation time is 0.83h. The remaining molten material in the distillation kettle is discharged while hot and cooled to room temperature to obtain a dark brown solid resin-like substance.

[0025] (3) The heavy fraction was placed in a centrifugal filter and centrifuged at a speed of 3000 r / min for 5 minutes to obtain 1.71 g of white crystalline solid magnolol product and 6.71 g of oily filtrate; 15 mL of non-polar organic solvent petroleum ether was added to the filtrate to precipitate crystals, which were collected by filtration to obtain 1.00 g of white crystalline solid magnolol product. GC analysis showed that the purity of magnolol and magnolol products (GC peak area normalization method) were 87.31% and 85.01%, respectively. Example 5

[0026] A method for extracting and separating magnolol and honokiol from magnolia bark oil by superheated steam distillation, comprising the following process steps: (1) 250 g of Magnolia officinalis oil was added to a steam distillation kettle equipped with an oil bath indirect heating device, and heated until the material temperature was raised to 110° C., and then superheated water vapor with a pressure of normal pressure (0.1 MPa), a temperature of 230° C., and a flow rate of 1200 g / h was introduced to perform steam distillation, and the oil bath heating power was adjusted to control the material temperature rise rate and the final distillation temperature to be 230° C., so that the distillation process was carried out smoothly; (2) The evaporated oil-water mixed gas is condensed and cooled, and the oil and water are separated. The evaporated fraction is automatically divided into two categories according to the boiling point, density, and aggregation form. The light fraction of oily liquid with a density less than water is 22.54g, and the heavy fraction of viscous oil with a density greater than water and containing crystals is 68.34g. When the evaporated fraction does not increase significantly, the distillation is terminated. The distillation time is 0.75h. The remaining molten material in the distillation kettle is discharged while hot and cooled to room temperature to obtain a dark brown solid resin-like substance.

[0027] (3) The heavy fraction was placed in a centrifugal filter and centrifuged at a speed of 4000 r / min for 5 minutes to obtain 13.67 g of white crystalline solid magnolol product and 54.66 g of oily filtrate; 70 mL of non-polar organic solvent petroleum ether was added to the filtrate to precipitate crystals, and 9.38 g of white crystalline solid magnolol product was obtained by filtration. GC analysis showed that the purity of magnolol and magnolol products (GC peak area normalization method) were 88.34% and 86.23%, respectively. Example 6

[0028] A method for extracting and separating magnolol and honokiol from magnolia bark oil by superheated steam distillation, comprising the following process steps: (1) 400 g of Magnolia officinalis oil was added to a steam distillation kettle equipped with an oil bath indirect heating device, and heated until the material was heated to 110° C., and then superheated steam with a pressure of normal pressure (0.1 MPa), a temperature of 230° C., and a flow rate of 1200 g / h was introduced to perform steam distillation, and the oil bath heating power was adjusted to control the material heating rate and the final distillation temperature to be 230° C., so that the distillation process was carried out smoothly; (2) The evaporated oil-water mixed gas was condensed and cooled, and the oil and water were separated. The evaporated fractions were automatically divided into two categories according to their boiling point, density, and aggregation form. 51.34 g of an oily liquid light fraction with a density less than that of water and 92.23 g of a viscous oily heavy fraction with a density greater than that of water and containing crystals were obtained. When there was no obvious increase in the evaporated fraction, the distillation was terminated. The distillation time was 1.3 h. The remaining molten material in the distillation kettle was discharged while hot and cooled to room temperature to obtain a dark brown solid resin-like substance.

[0029] (3) The heavy fraction was placed in a centrifugal filter and centrifuged at a speed of 4500r / min for 5 minutes to obtain 18.44g of white crystalline solid magnolol product and 73.78g of oily filtrate; 90mL of non-polar organic solvent petroleum ether was added to the filtrate to precipitate crystals, which were collected by filtration to obtain 14.57g of white crystalline solid magnolol product. According to GC analysis, the purity of magnolol and magnolol products (GC peak area normalization method) were 87.82% and 89.67%, respectively. Example 7

[0030] A method for extracting and separating magnolol and honokiol from magnolia bark oil by superheated steam distillation, comprising the following process steps: (1) 600 g of Magnolia officinalis oil was added to a steam distillation kettle equipped with an oil bath indirect heating device, and heated until the material was heated to 110° C., and then superheated steam with a pressure of normal pressure (0.1 MPa), a temperature of 230° C., and a flow rate of 1200 g / h was introduced to perform steam distillation, and the oil bath heating power was adjusted to control the material heating rate and the final distillation temperature to be 230° C., so that the distillation process was carried out smoothly; (2) The evaporated oil-water mixed gas was condensed and cooled, and the oil and water were separated. The evaporated fractions were automatically divided into two categories according to their boiling point, density, and aggregation form. 64.8 g of an oily liquid light fraction with a density less than that of water and 151.27 g of a viscous oily heavy fraction with a density greater than that of water and containing crystals were obtained. When there was no obvious increase in the evaporated fraction, the distillation was terminated. The distillation time was 2.1 h. The remaining molten material in the distillation kettle was discharged while hot and cooled to room temperature to obtain a dark brown solid resin-like substance.

[0031] (3) The heavy fraction was placed in a centrifugal filter and centrifuged at a speed of 5000 r / min for 5 minutes to obtain 31.75 g of white crystalline solid magnolol product and 119.44 g of oily filtrate; 130 mL of non-polar organic solvent petroleum ether was added to the filtrate to precipitate crystals, which were collected by filtration to obtain 20.30 g of white crystalline solid magnolol product. The actual pictures of the separated magnolol product and magnolol product are shown in Figure 2 and Figure 3 GC analysis showed that the purity of magnolol and honokiol products (GC peak area normalization method) were 87.31% and 89.34%, respectively. Example 8

[0032] Recrystallization and Purification of Magnolol and Honokiol Using cyclohexane as solvent, the magnolol and honokiol products obtained in the above Example 7 are recrystallized and purified, and the operation steps are as follows: weigh 1g of the magnolol product separated in Example 7, add 40mL of non-polar organic solvent cyclohexane, heat in a water bath at 60°C to dissolve, recrystallize twice, and obtain 0.78g of magnolol (HPLC purity is 98%); weigh 1g of the honokiol product separated in Example 7, add 7mL of organic solvent cyclohexane, heat in a water bath at 60°C to dissolve, recrystallize twice, and obtain 0.58g of honokiol (HPLC purity is 98%). The liquid chromatogram of the magnolol and honokiol products obtained after purification is shown in Figure 4 and Figure 5 .

Claims

1. A method for extracting and separating magnolol and honokiol from magnolia bark oil by superheated steam distillation, characterized in that: The process steps include: (1) Magnolia officinalis oil is added to a steam distillation kettle equipped with a heating device, and heated until the material temperature rises to 110°C. Then, superheated water vapor with a pressure of normal pressure or less than 0.2 MPa and a temperature of 150 to 250°C is introduced to perform steam distillation. The heating temperature of the distillation kettle, the temperature and flow rate of the superheated water vapor are regulated to adjust the material temperature rise rate and the final distillation temperature is controlled to be 220 to 250°C, so that the distillation process proceeds smoothly; (2) The distilled oil-water mixed gas is condensed and cooled, and the oil and water are separated. The fractions are collected in different sections or categories according to boiling range, density, and aggregation form to obtain an oily liquid light fraction with a density less than water and a viscous oily heavy fraction with a density greater than water and containing crystals. When the distilled fraction does not increase significantly, the distillation is completed, and the remaining molten material in the distillation kettle is discharged while hot and cooled to room temperature to obtain a dark brown solid resin-like substance. (3) placing the heavy fraction in a centrifugal filter for centrifugal filtration to separate a white or light yellow crystalline solid magnolia ol product and an oily filtrate; adding a non-polar organic solvent such as petroleum ether or cyclohexane to the filtrate to precipitate a crystalline precipitate, and collecting the precipitate by filtration to obtain a white crystalline solid and magnolia ol product.

2. The method for extracting and separating magnolol and honokiol from magnolia bark oil according to claim 1, characterized in that: The Magnolia officinalis oil is a primary extract obtained by extracting and separating magnolol and honokiol from the Magnolia officinalis plant. It refers to an oily liquid or viscous substance obtained by extracting and processing the extract obtained from Magnolia officinalis bark and / or leaves, and then desolventizing, evaporating and concentrating the extract. The extraction and processing methods include but are not limited to solvent extraction, supercritical CO2 fluid or subcritical fluid extraction.

3. The method for extracting and separating magnolol and honokiol from magnolia bark oil by superheated steam distillation according to claim 1, characterized in that: The distillation temperature is controlled below 250°C during the entire distillation process.

4. The method for extracting and separating magnolol and honokiol from magnolia bark oil by superheated steam distillation according to claim 1, characterized in that: The centrifugal filtration separation condition is a rotation speed of 1000 to 5000 r / min -1 , time: 5 to 15 minutes.

5. The method for extracting and separating magnolol and honokiol from magnolia bark oil by superheated steam distillation according to claim 1, characterized in that: The purity of the separated magnolol and honokiol products is over 85%.

6. The method for extracting and separating magnolol and honokiol from magnolia bark oil by superheated steam distillation according to claim 1, characterized in that: By using cyclohexane as solvent, the separated magnolol and honokiol products are further purified by recrystallization, and magnolol and honokiol products with a purity of 98% can be obtained.

Images