KR20080005724A - Method for separation and purification of corosolic acid from corosolic acid-containing materials - Google Patents

Abstract

A method of extracting and purifying corosolic acid from a material containing corosolic acid is provided to obtain high-purity corosolic acid efficiently by a successive process containing an extraction, chromatography, precipitation and high performance liquid chromatography. A material containing corosolic acid is extracted with an organic solvent such as C1-5 lower alcohol and concentrated. The obtained solid material is melted in an organic solvent and subjected to normal phase chromatography using one or more solvents selected from the group consisting of chloroform, methanol, dichloromethane, benzene, acetone, hexane and ethyl acetate to obtain an active fraction which is then subjected to reverse phase high performance liquid chromatography. The organic solvent is selected from the group consisting of ethanol, methanol and acetone. The material containing corosolic acid contains a plant body, callus, cell or cell suspension cultures of a plant selected from the group consisting of Lagerstroemia speciosa, Eriobotrya japonica, Ternstroemia gymnanthera, Crataegus pinnatifida and Tiarella polyphylla.

Description

Extraction and purification method for obtaining high purity corosolic acid from corosolic acid-containing substance {METHOD FOR SEPARATION AND PURIFICATION OF COROSOLIC ACID FROM COROSOLIC ACID-CONTAINING MATERIALS}

FIG. 1 is a result of high performance liquid chromatography (HPLC) analysis of an extract dried after ethanol organic solvent extraction in Example 1 of the present invention.

Figure 2a is the ethanol extract carried out in Example 2 of the present invention after reversed phase chromatography using ethanol / purified water as the mobile phase HPLC analysis.

2b is an HPLC analysis result after ethanol / purified water precipitation performed in Example 3 of the present invention.

Figure 3 shows the results of HPLC analysis after high performance liquid chromatography using ethanol as the developing solvent of the active fraction carried out in Example 4 of the present invention.

[Industrial use]

The present invention relates to a method for extracting and purifying corosolic acid from a corosolic acid-containing substance in high yield and high purity. More specifically, the extract is concentrated after extracting corosolic acid from a corosolic acid-containing substance using an organic solvent. To dry; Purifying the concentrated dried material obtained above by chromatography or recrystallization; It relates to a method for purifying corosolic acid comprising the step of purifying the reaction product by high performance liquid chromatography.

[Prior art]

Corosolic acid is known to be present in the banaba, a family of budaceae, the leaves of loquat, a rose family, and the flesh of hawthorn. These plants have been widely used for the prevention and treatment of diabetes since 1500 years throughout Southeast Asia. As a plant, it is commercialized in the form of tea in Japan, and its stability is also confirmed.

Corosolic acid is a substance that acts to lower the blood sugar level by activating the glucose transport pathway of the cell membrane similar to insulin [Chem.pham.Bull. 41 (12) 2129-2131 (1993)], and in subsequent clinical trials, corosolic acid not only lowers blood sugar without side effects, but also suppresses the rise in blood sugar levels (Jounrnal of Ethnophamacology 87 (2003) 115-117), It is also known to play an important role (US Pat. No. 6,78,4206). However, the supply of this material is mainly produced by direct heat extraction and alcohol extraction from plants such as banaba, loquat, etc., the content is very low, there are many difficulties in high purity purification. Moreover, despite the trend of increasing demand for corosolic acid in health foods and medicines, there have been various problems in the supply of corosolic acid due to such low productivity limitation.

In US Pat. No. 6,485,760, a ethanol solution, methanol solution, or hot water is extracted from the leaves of Banaba and then dried using a dry matter having a content of 0.1-15% corosolic acid from which activated pigments are removed to remove pigments. The experiment was performed. However, the proposed method is a method for obtaining low-purity corosolic acid by extraction, and high purity corosolic acid is required for use as a medicine, and thus there is a limit to its use.

In US 2003/0165581, Prunella Linn or Rabdosis (Blumn) Hasskarl plants were subjected to extraction using a polar solvent such as ethanol, and the extracted materials were distributed using petroleum ether and water, and then 1 A method of obtaining a corosolic acid extract of about% and performing at least one column chromatography and two recrystallizations to obtain at least 98% of the corosolic acid is disclosed. In this case, the growth cycle of the plant is shorter than that of the banaba leaves, so that it is possible to obtain a relatively large amount of corosolic acid within the same time, but this also has a limitation on industrial scale production by separating from the plant. In addition, in terms of yield, the yield is not only 10-15% or more in the first ethanol extraction step, but 5% or more in the dispensing step, and the process is complicated by several column chromatography and recrystallization. There is a disadvantage that requires a lot of time and effort to obtain high purity corosolic acid.

A method of producing corosolic acid by semi-synthesis from ulsoric acid, which is a precursor of corosolic acid, has been published (US Patent Publication No. 2005/0020681), but this is also limited to supply because it is extracted from a natural plant, which is a precursor of ulsoric acid. It is economically inefficient, such as having to synthesize again. In addition, productivity is judged to be at a low level similar to the content of corosolic acid present in natural leaves.

Such a conventional technology is very inefficient in producing high purity corosolic acid despite increasing demand for corosolic acid in industries such as health food and pharmaceuticals, and its production is limited due to low productivity. Therefore, there is an urgent need for the development of a technique for producing a bioactive substance corosolic acid in a high purity and efficient manner.

The present invention is to solve the above problems, to provide a method for extracting and purifying corosolic acid in high purity and high yield from the corosolic acid-containing material.

Still another object of the present invention is to provide a method for separating and purifying corosolic acid in high purity and high yield in a simplified process using only one or more organic solvents.

The present invention relates to a method for extracting and purifying corosolic acid from a corosolic acid-containing material in high yield and high purity. To dry; Purifying the concentrated dried material obtained above by chromatography or recrystallization; It relates to a method for purifying corosolic acid comprising the step of purifying the reaction product by high performance liquid chromatography.

As a starting material for obtaining extracted and purified corosolic acid according to the present invention, 'corosolic acid-containing substance' is a plant species known to produce all corosolic acid, callus derived from it, plant cells, and plant cell suspension. Include all cultures. An example of a plant known to produce the above corosolic acid is Lagerstroemia. speciosa ), loquats ( Eribotrya japonica ), cedar ( Ternstroemia gymnanthera ), hawthorn ( Crataegus) pinnatifida ), pansy ( Tiarella polyphylla ) and the like, but is not limited thereto. The area used is not limited, and the whole plant, leaves, pulp, stems, roots, flowers and the like can be used, and among these, it is best to use the leaf area.

More specifically, in one embodiment of the present invention, the method of extracting and purifying the corosolic acid of the present invention,

(a) extracting by adding an organic solvent to the corosolic acid-containing material and concentrating and drying the extract;

(b1) dissolving the dried product obtained in step (a) in an organic solvent, and then performing normal phase chromatography to obtain an active fraction; And

(c) performing high-performance liquid reverse phase chromatography on the active fraction obtained in step (b1) to purify the corosolic acid in the active fraction.

In another embodiment of the present invention, the method of extracting and purifying the corosolic acid of the present invention,

(a) extracting by adding an organic solvent to the corosolic acid-containing material and concentrating and drying the extract;

(b1 ') dissolving the dried product obtained in step (a) in an organic solvent, and then performing reversed phase chromatography to obtain an active fraction; And

(c) performing high-performance liquid reverse phase chromatography on the active fraction obtained in step (b1 '), and may comprise the step of purifying corosolic acid in the active fraction.

In another embodiment of the present invention, the method of extracting and purifying the corosolic acid of the present invention,

(a) extracting by adding an organic solvent to the corosolic acid-containing material and concentrating and drying the extract;

(b2) dissolving the dried material obtained in step (a) in a solvent selected from the group consisting of ethanol, methanol and acetone, and then precipitating by adding purified water to the solution; And

(c) performing high-performance liquid reverse phase chromatography on the precipitate produced in the step (b2), and may include the step of purifying the corosolic acid in the precipitate.

As the organic solvent added to the corosolic acid-containing material in step (a), it can be selected from among lower alcohols having 1 to 5 carbon atoms including methanol, ethanol, propanol, isopropanol and butanol, and preferably , Methanol or ethanol can be used. The alcohol may be used in the state of 100% alcohol, or in an aqueous solution at a concentration of 10 or more and less than 100% (v / v). In the present specification, unless otherwise specified, the 'alcohol aqueous solution' is defined as including both the mixture of alcohol and water and the case of 100% alcohol. In the case of extraction using alcohol, the higher the alcohol concentration, the better the extraction efficiency, and the minimum alcohol concentration for effective extraction is 10% (v / v). For example, when extracted using methanol, ethanol, or propanol, the alcohol aqueous solution may be used in a concentration of 10 to 100% (v / v), in order to obtain a better extraction efficiency concentration of 80 to 100% (v / v), with a concentration of 100% being most preferred. The amount of the alcohol or aqueous alcohol solution used as the organic solvent in the step (a) may be 20 to 3000% (v / w) based on the dry weight of the corosolic acid-containing material, 100 to 2000% (v / w) It is preferable. When used as an organic solvent, if the amount of alcohol or an aqueous solution of alcohol is less than 20%, the amount of alcohol is too low compared to the dry matter, making extraction difficult, and more than 3000% (v / w) can be used, but the amount of solvent used is too high, resulting in poor economic efficiency. There is this.

For sufficient extraction of corosolic acid, the extraction of step (a) is preferably carried out by stirring for 30 minutes to 48 hours at a stirring speed of 50 to 300 rpm at a temperature of 15 ℃ to 80 ℃. In addition, the extraction efficiency is 80% or more when extracted about three times, and extraction efficiency close to 100% can be obtained by extracting about five times. Therefore, the number of extraction is good to repeat 1 to 5 times. The extracted corosolic acid is concentrated under reduced pressure in a water bath of 25 to 35 ℃ and dried by vacuum drying at about 35 ℃.

The corosolic acid extract obtained as described above is purified by performing normal phase or reverse phase column chromatography according to step (b1) or (b1 '), or organic selected from the group consisting of methanol, ethanol and acetone according to step (b2). After dissolving in a solvent it can be purified by adding purified water to precipitate. Preferably, purification by reverse phase chromatography is preferred.

(b1) or (b1 '), the dried material obtained in step (a) is a lower alcohol, chloroform, dichloromethane, benzene, having 1 to 5 carbon atoms in a volume of 50 to 200 times based on 1 g of the dry weight. Chromatography may be performed using a solution sufficiently dissolved in one or more organic solvents selected from the group consisting of acetone, hexane and ethyl acetate.

In the case of purification by normal phase column chromatography, silica gel, starch, diatomaceous earth powder, cellulose or the like may be used as the filler of the column. In the case of using silica gel, silica gel commonly used for column chromatography, for example, silica gel 40 (63 to 200 μm), silica gel 60 (63 to 200 μm), silica gel 60F254 (200 to 500 μm) and the like can be used. As the developing solvent, one or more organic solvents may be selected from the group consisting of chloroform, methanol, dichloromethane, benzene, acetone, hexane and ethyl acetate. In order to obtain high purity corosolic acid, a mixed solvent in which methanol and chloroform are mixed in a volume ratio of 2 to 50:98 to 50 (methanol volume: chloroform volume) may be used as a most preferable developing solvent, and a methanol and chloroform volume ratio of 5: Most preferred is a mixed solvent of 95 (methanol volume: chloroform volume).

When purified by reverse phase column chromatography, the filler of the column may be ODS (Octadecylsilylated, C18), C8, C4, CN or phenyl, etc., preferably ODS (Octadecylsilylated, C18, 40 ~ 100㎛) Can be used. As the developing solvent, one or more selected from the group consisting of methanol, ethanol, acetonitrile, water and the like can be used. In order to obtain high purity corosolic acid, it is preferable to use 70 to 100% (v / v) methanol / water, or 55 to 100% (v / v) ethanol / water, and 85% (v / v) methanol Particular preference is given to using / water or 65% (v / v) ethanol / water.

Further, in step (b2), the extract dried product obtained in step (a) can be dissolved by adding ethanol, methanol or acetone, and purified by adding purified water to form a precipitate. At this time, 1 to 10 mg of the dry matter may be dissolved per 1 ml of ethanol, methanol or acetone. If the amount of solvent is too low, the yield of corosolic acid is lowered. Therefore, in order to obtain corosolic acid in an excellent yield, the dry matter content per 1 ml of solvent is preferably 1 mg or more. If the amount of solvent is too high, the purity of corosolic acid is lowered, so that high purity In order to obtain the corosolic acid, the dry matter content per 1 ml of solvent is preferably 10 mg or less. The purified water may be added in a 0.1 to 0.9 volume ratio (methanol or acetone volume: purified water volume = 1: 0.1 to 0.9) relative to methanol or acetone volume 1, preferably in a ratio of 1: 0.3 to 0.6 volume, and for ethanol volume 1 Can be added in a volume ratio of 0.5 to 1.5 (ethanol volume: purified water volume = 1: 0.5 to 1.5), preferably in a volume ratio of 1: 0.8 to 1.2. The higher the ratio of purified water, the lower the purity, and the lower the ratio, the lower the yield, so it is preferable to use it in the above volume ratio range.

After addition of purified water, the immersion temperature and duration are not limited, and in consideration of yield, efficiency compared to the required time, and the like, the settling time is preferably 1 hour to 4 days, and preferably 1 hour to 1 day. Immersion temperature is possible in the temperature range which does not need excessive heating or cooling, for example, can be 0-30 degreeC, Preferably it is 4-25 degreeC.

In step (c), the active fraction obtained in step (b1), (b1 '), or (b2) is purified by high performance liquid chromatography. At least one selected from the group consisting of methanol, ethanol, acetonitrile, water, and the like may be used as a developing solvent for reverse phase high performance liquid chromatography in step (c). In step (C), hydrophobic resin column high performance liquid chromatography may be used, and in this case, reverse phase high performance liquid chromatography filled with ODS (Octadecylsilylated, C18), C8, or C4 to remove nonpolar impurities may be used as a developing solvent. By performing with 85% (v / v) methanol / purified water or 55-75% (v / v) ethanol / purified water, high purity corosolic acid of at least 95% can be obtained.

In the method for extracting and purifying corosolic acid from the corosolic acid-containing material of the present invention, the purity and recovery range of the corosolic acid that can be obtained in each step according to the purification step (b1 or b2) are shown in Table 1 below. As shown.

water(%) Recovery rate (b1, b1 ') (%) Recovery rate (b2) (%) Starting corosolic acid-containing substance 3-9 100 100 Solvent Extraction: Step (a) 6-26 85-95 85-95 Column Chromatography: Step (b1, b1 ') 25-65 70-90 Organic solvent / purified water precipitation: step (b2) 11-37 65-93 Reversed-phase high performance liquid chromatography: step (c) 90-95 75-85 75-85 all 90-95 44.6-72.7 41.3-75.1

As shown in Table 2, according to the method for extracting and purifying the corosolic acid of the present invention, it is possible to obtain a high purity corosolic acid having a purity of 90% or more with a high yield of 40% or more.

Purity and recovery of corosolic acid herein was calculated by quantitative analysis using HPLC (High Performance Liquid Chromatography) under the conditions of Table 2.

[ Example ]

Hereinafter, the present invention will be described in more detail with reference to Examples. These examples are only for illustrating the present invention more specifically, and the scope of the present invention is not limited to these examples.

Example  1: Organic Solvent Extraction from Plant Cell Culture Solution

Plant cells obtained by culturing cell lines (KCTC 10822BP, KCTC 10823BP) derived from loquat or banaba prepared by Korean Patent Application No. 10-2005-0058377 were collected and dried by hot air at 50 ° C for 48 hours. 100 g of dried plant cells were added to 100% methanol, 100% ethanol, and 2000 ml of 80% (v / v) ethanol / purified water solution, respectively, and the mixture was stirred at room temperature or 80 ° C. for 1 hour and filtered to obtain an extract. Then, the mixture was concentrated under reduced pressure and dried to obtain an dried product. The extracted dry matter thus obtained was analyzed by high performance liquid chromatography (HPLC), and the results are shown in FIG. 1. The purity and yield of corosolic acid obtained by the above results are shown in Table 3 below.

Experiment number Solvent type Extraction temperature water(%) % Recovery A 100% methanol Room temperature 9.93 99.00 B 100% ethanol Room temperature 11.95 85.75 C 100% ethanol 80 ℃ 10.55 96.53 D 80% ethanol / purified water Room temperature 8.60 78.12 E 80% ethanol / purified water 80 ℃ 8.56 93.58

Example  2: by chromatography Dry matter  refine

Example  2-1. Chastity column  Chromatography

After dissolving 300 mg of the methanol extract obtained in Experiment No. A of Example 1 with 20 ml of chloroform, silica gel 60N (timely, Japan) was filled with 5% (v / v) methanol / chloroform in equilibrium and mobile phases. Phase chromatography was performed by applying an isocratic method to a 14 mm diameter 400 mm long column. As a result, an active fraction having a purity of 34% was obtained with a yield of 72.6%.

Example  2-2. Reverse column  Chromatography-Methanol

300 mg of the methanol extract obtained in Experiment No. A of Example 1 was dissolved in 30 ml of 100% methanol by heating at 80 ° C., and then 80%, 85%, and 90% (v / v) methanol / purified water in the equilibrium and mobile phases. Reverse phase chromatography was performed by applying the solution to a 15.5 mm diameter 900 mm column filled with ODS (timely, 100 um, Japan). The purity and yield of the corosolic acid thus obtained are shown in Table 4 below.

Experiment number Mobile phase solvent (% (v / v) methanol / purified water) water(%) % Recovery F 90% 59.3 85.6 G 85% 60.4 90.4 H 80% 57.8 83.4

Example  2-3. Reverse column  Chromatography-ethanol

300 mg of the ethanol extract obtained in Experiment No. B of Example 1 was dissolved in 30 ml of 100% ethanol by heating at 80 ° C., and 60%, 65%, and 70% (v / v) ethanol / purified water were used as equilibrium and mobile phases, respectively. Reverse phase chromatography was performed by applying to a diameter 15.5mm long 900mm column filled with ODS (timely, 100um, Japen). HPLC was performed on the active fractions obtained above, and the results are shown in FIG. 2A. The purity and yield of the corosolic acid thus obtained are shown in Table 5 below.

Experiment number Mobile phase solvent (% (v / v) ethanol / purified water) water(%) % Recovery I 70% 58.3 89.6 J 65% 57.6 90.4 K 60% 57.8 88.7

Example  3: by precipitation Dry matter  refine

Example  3-1. Methanol / Purified water  Sedimentation

After dissolving 5 ml of methanol in 50 mg of the methanol extract obtained in Experiment No. A of Example 1, 1.0 ml, 1.5 ml, 2.0 ml, and 2.5 ml of purified water were added thereto, and the mixture was left at 4 ° C. for 24 hours to precipitate. The solution was filtered to recover the resulting precipitate. The recovered precipitate is corosolic acid, and the purity and yield of the corosolic acid thus obtained are shown in Table 6 below. Indicated.

Experiment number Methanol Purified water water(%) % Recovery L 5ml 1.0ml 23.3 63.6 M 5ml 1.5ml 20.4 74.7 N 5ml 2.0ml 19.0 85.6 O 5ml 2.5ml 18.5 93.7

Example  3-2. ethanol/ Purified water  Sedimentation

After dissolving 5 ml of ethanol in 50 mg of the ethanol extract obtained in Experiment No. B of Example 1, 3.0 ml, 4.0 ml, 5.0 ml, and 6.0 ml of purified water were added, and the mixture was left at 4 ° C. for 24 hours to precipitate. The solution was filtered to recover the resulting precipitate. HPLC was performed on the precipitate, and the result is shown in FIG. 2B. The purity and yield of the corosolic acid thus obtained are shown in Table 7 below.

Experiment number Methanol Purified water water(%) % Recovery P 5ml 3.0ml 22.1 82.7 Q 5ml 4.0ml 21.6 87.4 R 5ml 5.0ml 19.7 91.6 S 5ml 6.0ml 19.4 93.4

Example  3-3. Acetone / Purified water  Sedimentation

After dissolving 5 ml of acetone in 50 mg of the methanol extract obtained in Experiment No. A of Example 1, 1.0 ml, 1.5 ml, 2.0 ml, and 2.5 ml of purified water were added, and the mixture was left at 4 ° C. for 24 hours to precipitate. The solution was filtered to recover the resulting precipitate. The purity and yield of the corosolic acid thus obtained are shown in Table 8 below .

Experiment number Acetone Purified water water(%) % Recovery T 5ml 1.0ml 18.2 30.9 U 5ml 1.5ml 17.9 56.8 V 5ml 2.0ml 18.3 80.1 W 5ml 2.5ml 18.1 92.6

Example  4: high speed liquid In reversed phase chromatography  by Corosolic  refine

Example  4-1. High speed liquid Reversed phase chromatography Methanol

The active fraction obtained in Experiment No. G of Example 2-2 was filtered under reduced pressure and dried in vacuo at 35 ° C., and then dissolved by heating at 80 ° C. in 100% methanol. The solution was purified by subjecting the ODS-filled reversed phase high performance liquid chromatography to isocratic method using 77.5% methanol / purified water three times by chromatography. As a result, corosolic acid having a purity of 95% was obtained in a yield of 80%.

Example  4-2. High speed liquid Reversed phase chromatography -ethanol

The active fraction obtained in Experiment No. J of Example 2-3 was filtered under reduced pressure and vacuum dried at 35 ° C., and then dissolved by heating at 80 ° C. in 100% ethanol. The solution was purified by applying chromatography to ODS-filled reverse phase high performance liquid chromatography using isocratic method using 65% ethanol / purified water as a developing solvent. The purity of the corosolic acid thus obtained was 95% and the yield was 80%.

Industrial Applicability In the present invention, in the purification of corosolic acid, extraction, chromatography, precipitation, high-performance liquid chromatography, etc., are performed efficiently to obtain high purity corosolic acid. Production is possible.

Claims (12)

(a) extracting by adding an organic solvent to the corosolic acid-containing material and concentrating and drying the extract; (b1) dissolving the dried product obtained in step (a) in an organic solvent, and then performing normal phase chromatography to obtain an active fraction; And (c) performing high-performance liquid reverse phase chromatography on the active fraction obtained in step (b1) to purify the corosolic acid in the active fraction. Method of purifying corosolic acid comprising a. (a) extracting by adding an organic solvent to the corosolic acid-containing material and concentrating and drying the extract; (b1 ') dissolving the dried product obtained in step (a) in an organic solvent, and then performing reversed phase chromatography to obtain an active fraction; And (c) performing high-performance liquid reverse phase chromatography on the active fraction obtained in step (b1 ') to purify the corosolic acid in the active fraction. Method of purifying corosolic acid comprising a. (a) extracting by adding an organic solvent to the corosolic acid-containing material and concentrating and drying the extract; (b2) dissolving the dried material obtained in step (a) in a solvent selected from the group consisting of ethanol, methanol and acetone, and then precipitating by adding purified water to the solution; And (c) performing high-performance liquid reverse phase chromatography on the precipitate produced in step (b2) to purify the corosolic acid in the precipitate. Method of purifying corosolic acid comprising a. The plant according to any one of claims 1 to 3, wherein the corosolic acid-containing material of step (a) is a plant of at least one plant selected from the group consisting of banaba, loquat, cedar, hawthorn and pansy. A method for purifying corosolic acid, which is a callus, plant cell or plant cell suspension culture. The corrolic acid according to any one of claims 1 to 3, wherein the organic solvent of step (a) is at least one alcohol selected from the group consisting of lower alcohols having 1 to 5 carbon atoms or an aqueous solution of the alcohol. Method of purification. The method of claim 1, wherein the developing solvent of the normal phase chromatography of step (b1) is at least one selected from the group consisting of chloroform, methanol, dichloromethane, benzene, acetone, hexane and ethyl acetate. Method of purification. The method of claim 6, wherein the developing solvent of the normal phase chromatography of step (b1) is a mixed solvent of 2 to 50% (v / v) of methanol and 98 to 50% (v / v) of chloroform. Method for Purifying Colosolic Acid. The method of claim 2, wherein the developing solvent of reverse phase chromatography in step (b1 ') is a 55-100% (v / v) aqueous solution of methanol, ethanol and acetonitrile. According to claim 3, wherein in step (b2) the amount of dry matter obtained in step (a) dissolved per 1 ml of the ethanol, methanol or acetone is 1 to 10 mg, the amount of purified water added is the ethanol, methanol or acetone Method for purifying corosolic acid, characterized in that the volume ratio of 0.1 to 1.5 with respect to the volume ratio 1. The process of any one of claims 1 to 3, wherein the developing solvent for reverse phase high performance liquid chromatography in step (c) is at least one selected from the group consisting of methanol, ethanol, acetonitrile, and water. Purification method of corosolic acid. The process of any one of claims 1 to 3, wherein the developing solvent of the high-performance reversed phase chromatography of step (c) is an aqueous solution of 55 to 100% (v / v) of ethanol, methanol or acetonitrile. The purification method of corosolic acid which makes it. The organic solvent of claim 1 or 2, wherein the organic solvent of step (b1) or (b1 ') is selected from the group consisting of lower alcohols having 1 to 5 carbon atoms, chloroform, dichloromethane, benzene, acetone, hexane and ethyl acetate. A method for purifying corosolic acid, characterized in that it is at least one kind.

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