JP2003026533A - Extract of ginkgo leaf and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To develop an extract of ginkgo leaves having high water solubility and simply improved in color tone and to develop a method for producing the extract. SOLUTION: The extract of ginkgo leaves is treated with an inorganic flocculating agent. Thereby, it was found that a pigment component and a water- insoluble component are flocculated and precipitated and the extract of ginkgo leaves without causing return of color in purification and concentration steps of an active ingredient, improved in color tone and having good water solubility is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ginkgo biloba extract having improved color tone and water solubility and a method for producing the same as foods, cosmetics, pharmaceutical materials and the like.

[0002]

2. Description of the Related Art Ginkgo biloba leaves contain active ingredients such as terpenes, flavonoids and polyphenols (Fragrance Journal, Extra edition, (198
6) 297-299). Ginkgo biloba extract extracted from ginkgo leaves is senile dementia (cerebrovascular type, Alzheimer's type), cerebral infarction / stroke (cerebral thrombosis, memory improvement), peripheral blood circulation disorder (stiff shoulders, numbness of limbs, coldness) Blood flow improvement (arteriosclerosis, eye strain), hypertension, vision,
It is effective for hearing loss, prevention of aging, etc., and no serious side effects have been reported.
In Belgium, etc., cerebral circulation metabolism (memory impairment, dizziness,
It has been used as a therapeutic drug for improving tinnitus, headache, etc.).

In Japan, it appeared in 1984 as a health food, and thereafter, a test on the blood circulation promoting effect by external application of ginkgo biloba extract (JP-A-1-117816), a hair regrowth evaluation test for mice (Fragrance Journal,
(1993) pp. 27-36), the effect as a cosmetic was also recognized, and the ginkgo biloba extract has been added to cosmetics.

In the United States, in October 1994, health foods were officially recognized by the enforcement of the "Nutrition Supplements, Health and Education Act 1994" concerning the revision of the Food, Drug, Cosmetics Act and the establishment of standards for dietary supplements. Ginkgo biloba extract showed explosive growth. After that, it spread to Europe as a health food.

However, ginkgo biloba extract has a problem in developing allergic ingredients, bitterness ingredients, poorly water-soluble ingredients, pigment ingredients and the like as health foods and cosmetics. Therefore, a method for producing ginkgo biloba extract, which is a salicylic acid derivative that has an action of causing allergic dermatitis, has been developed. Gincoric acid 50 ppm or less), JP 2000-
No. 128792 (Gincoric acid 10 ppm or less) is disclosed.

A method for reducing the content of all alkylphenols to 10 ppm or less, not as a salicylic acid derivative (JP-A-3-264533 and JP-A-3-27562).
No. 9, JP-A-3-279331, JP-A-3-
No. 279332, Japanese Patent Laid-Open No. 4-288019)
It has been known. The flavone aglycone contained in the ginkgo biloba extract shows a positive result in the Ames test of the method for detecting mutagenicity, and therefore a method for producing a gingko biloba extract that does not contaminate them is provided (Japanese Patent Laid-Open No. 7-3811).
No. 71).

As a method for removing the bitterness and astringency in the ginkgo biloba extract, the ginkgo biloba extract-containing liquid is passed through a non-polar porous resin, and the bitterness component contained in the ginkgo biloba extract-containing liquid is non-polar. Japanese Patent Laid-Open No. 7-33671 discloses a method of removing bitterness by adsorbing and removing it on a porous resin and then allowing α-glycosyltransferase to act in the presence of starch.

As a method for improving the water solubility of ginkgo biloba extract, a method for enhancing water solubility by treating the insoluble component of ginkgo biloba extract with a glycosidase, transglycosidase, etc. (Japanese Patent Laid-Open No. 3-91490, (Kaihei 3-98592) or a method of treating with a non-polar porous resin by making it alkaline in the purification step (Japanese Patent Laid-Open No. 3-275).
No. 629, the present inventors), a basic compound is added to a ginkgo biloba extract extract to adjust the pH to 6.0 or higher, or a method of spray-drying this adjusted product on a water-soluble granular substrate (special feature). JP-A-5-271084 and JP-A-5-3448
No. 73), and further, a method of passing the ginkgo biloba extract-containing liquid through a non-polar porous resin so that the ginkgo biloba extract-containing liquid from which the poorly water-soluble components have been adsorbed and removed is reacted with α-glycosyltransferase ( Japanese Patent Laid-Open No. 7-33671) is disclosed.

As a method of utilizing the ginkgo biloba extract, in addition to health foods, candy can be used as processed foods (Japanese Patent Laid-Open No. Sho 62-62).
-190046), health drinks (JP-A-62-20)
No. 5028), chocolate (JP-A-2-3164).
No. 6), chewing gum (JP-A-2-31648), fortified rice (JP-A-10-165119),
Miso (Japanese Unexamined Patent Publication No. 11-243900), hair-growth agents as cosmetics (Japanese Unexamined Patent Publication No. 1-117816), external skin preparations (Japanese Unexamined Patent Publication No. 4-321615), bath composition (Japanese Unexamined Patent Publication No. 7-69862). The method of use is disclosed in various ways, such as Japanese patent publication).

When used as foods and cosmetics, in addition to the active ingredient content, harmful ingredient content and water solubility, the color tone is an important factor in utilizing it. As a method for improving the color tone of the ginkgo biloba extract, the ginkgo biloba extract is concentrated, diluted with water containing ammonium sulfate, extracted with methyl ethyl ketone and concentrated, and the concentrate is diluted with water and ethanol, and then an aqueous solution of a lead salt is added as an aqueous solution. Is added until the color changes from brown to yellowish brown to remove the precipitate (JP-A-3-2793).
No. 31). However, since this method uses a highly toxic metal compound, it is not preferable as a method for producing a ginkgo biloba extract for food and cosmetics.

In order to suppress the formation of coloring components when concentrating the separated liquid containing the ginkgo biloba extract, such as elution from ginkgo biloba extract or adsorbent, the pH is adjusted to 6 to 8 and below 80 ° C. There is known a method in which the content of the coloring component can be remarkably reduced by a method such as concentrating at a temperature of 1, or by concentrating in an inert gas atmosphere (JP-A-7-13817).
No. 1).

However, in the disclosed method, the distillation temperature is 80 ° C. or lower, and the temperature is too low to distill the water-soluble water-soluble organic solvent, so that the distillation rate is limited. Further, it can be said that the method of distilling in an inert gas atmosphere is a method which requires high manufacturing cost depending on the distillation equipment and operating conditions.

[0013]

DISCLOSURE OF THE INVENTION An object of the present invention is to develop a ginkgo biloba extract having a high water-solubility and a color tone easily improved, and a method for producing the same.

[0014]

Means for Solving the Problems As a result of intensive studies to achieve the above-mentioned object, the present inventors conclude that a pigment component and a water-insoluble component are condensed by treating an extract of ginkgo leaves with an inorganic condensing agent. It has been found that a ginkgo biloba extract, which has a good color tone and a good water solubility, does not cause color reversion during the process of purifying and concentrating the active ingredient, is obtained.

That is, the present invention is characterized in that (1) a ginkgo biloba extract having an absorbance of 0.04% or less at a wavelength of 540 nm, and (2) an extraction process of the gingko biloba extract includes a treatment step with an inorganic coagulant. A method for producing a ginkgo biloba extract, (3) the method for treating an inorganic flocculant is prior to the step for treating a hydrophobic adsorbent resin, (4) the method for producing a ginkgo biloba extract, (4) inorganic flocculation The method for producing a ginkgo biloba extract according to (2) or (3), characterized in that the agents are aluminum sulfate and slaked lime.

As a general method for producing a ginkgo biloba extract, the following flow is used. Raw material → Extraction → Distillation → (Hexane transfer) → Concentration → Hydrophobic adsorbent resin purification → Desorption → Distillation → Hydrophobic adsorbent resin refining → Concentration → Drying → Product It is characterized by the addition. In particular, the step of using the inorganic coagulant is preferably performed before the purification of the hydrophobic adsorption resin. The present invention will be specifically described below.

First, in the step of solvent extraction from dried ginkgo leaves, the solvent may be any solvent that can efficiently extract useful components such as flavone glycosides and terpenes contained in ginkgo leaves. However, in view of the next treatment with the inorganic condensing agent, it is preferable to use a hydrophilic organic solvent such as water, an organic solvent or a mixed solvent thereof. In particular, water, methanol, ethanol, propanol, isopropanol,
A hydrophilic organic solvent such as butanol, isobutanol, acetone, methyl ethyl ketone, or a mixed solvent thereof is preferable.

The extract obtained by extracting useful components from ginkgo leaves is concentrated. When the extraction solvent is an organic solvent or a mixed solvent with water, the concentration of the organic solvent in the extraction liquid is 20% to 30%.
When it becomes, hydrocarbons, alcohols, aldehydes and ketones, fatty acids, and alkylphenols such as ginkgolic acid can be efficiently removed by liquid-liquid extraction with a hydrophobic organic solvent.

After that, the organic solvent is distilled off by further concentrating. However, when the extraction solvent is water, the operation of liquid-liquid extraction can be omitted. Since the concentrate is acidic, add an alkaline agent such as calcium hydroxide, magnesium hydroxide, potassium hydroxide, sodium hydroxide, lithium hydroxide, potassium carbonate, sodium hydrogen carbonate, anhydrous sodium carbonate, etc.
Add an alkaline agent so that the pH of the concentrated solution is in the range of 4.5 to 7.0. At this time, the best alkaline agent used is calcium hydroxide (slaked lime).

Then, when an inorganic flocculant such as magnesium chloride, magnesium sulfate, calcium sulfate, aluminum sulfate, ferric chloride, polyaluminum chloride, polyferric sulfate is added, which is a feature of the present invention, the ginkgo leaves are removed. The extracted pigments, water-insoluble components, etc. are condensed and settled, so these are filtered off.

Aluminum sulfate is the best inorganic coagulant, but the ratio of alkaline agent to inorganic coagulant is important. That is, since the inorganic coagulant binds to useful components such as flavone glycosides contained in the ginkgo biloba extract, the ratio of the inorganic coagulant to the alkaline agent used is preferably in the range of 1: 3 to 1:20. The concentrated solution of ginkgo biloba extract subjected to this treatment turns from brown to pale yellow. However, if the amount of the inorganic flocculant used is increased, adsorption of the active ingredient also occurs, so it is better to reduce the amount used.

The concentrated liquid obtained by treating the ginkgo biloba extract with an inorganic coagulant is flavone glycosides, ginkgolides,
In order to increase the content of bilobalides, two kinds of hydrophobic porous resin are used. First, the first hydrophobic porous resin selectively adsorbs useful components such as flavone glycosides, ginkgolides and bilobalides contained in the concentrate obtained by treating the ginkgo biloba extract with an inorganic coagulant. A good hydrophobic porous resin that can be used is Duolite S-761, S-861, S-862, S-865, ES-8 manufactured by Diamond Shamrock.
61, ES-863, ES-865, ES-866., Amber Light XAD-2000, XAD-2, XAD-4, XAD- made by Rohm and Haas
7, XAD-26. , Mitsubishi Chemical's Diaion SP-206, SP-
207, SP-825, SP-865, HP-10, HP-20, HP-21, HP-30, H
P-40 and HP-50 are suitable.

The useful component of ginkgo biloba adsorbed on these hydrophobic porous resins is desorbed and eluted from the hydrophobic porous resin with a hydrophilic organic solvent or a mixed solvent of a hydrophilic organic solvent and water. Next, the eluent has an organic solvent concentration of 25%
Concentrate to below. As the second hydrophobic porous resin,
DIAION HP-20, HP-40, HP-50 and the like manufactured by Mitsubishi Chemical Corporation can be preferably used. The purpose of this hydrophobic porous resin treatment is to adsorb and remove harmful components such as allergy-inducing components in ginkgo leaves that could not be completely removed by the previous treatment. As described above, the ginkgo biloba extract purified and concentrated by a combination of extraction, treatment with an inorganic coagulant, and hydrophobic porous resin can be made into a powder extract by a concentrate or spray drying.

Through the above steps, the concentrated and purified Ginkgo biloba extract does not significantly change the color tone of the Ginkgo biloba extract when the second eluate is concentrated and heated, even if the heating temperature becomes high. Then, a ginkgo biloba extract having good water solubility can be obtained.

The steps of the present invention can be represented by a flow as follows. Raw material → Extraction → Distillation → (Hexane transfer) → Concentration → Inorganic flocculant → Filtration → Hydrophobic adsorption resin purification → Desorption → Distillation → Hydrophobic adsorption resin purification → Concentration → Drying → Product

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION Examples will be shown to specifically describe the present invention, but it goes without saying that the present invention is not limited to these. In the examples and comparative examples, the color tone of the ginkgo biloba extract was measured by a spectrophotometer [UV2200 manufactured by Shimadzu Corporation].
A]. The analysis conditions are described below.

[Measurement of Absorbance] Cell: 1 cm Quartz cell Wavelength: 540 nm Solvent: 50% by volume ethanol aqueous solution concentration: 200 mg / 100 ml [Example 1] Dry ginkgo biloba 500 crushed to 5 to 10 mm
g in a 5 L glass column, then 5 L of acetone with a water content of 20% by volume, and 2 using a magnet pump.
Circulation extraction was performed at room temperature for a period of time. The extract was extracted to obtain 3 L of extract. In addition, 2 L with 5 L of acetone with a water content of 20% by volume
The same operation was repeated once to obtain a total of 13 L of extract.

This extract was distilled under normal pressure. Distillation was stopped when 10.3 L of distillate was obtained. At this time, the liquid of the distillation residue contained 23% by volume of acetone. The distillation residue was transferred to a separating funnel, 0.5 L of hexane was added, and the mixture was shaken for liquid-liquid extraction. The lower layer was put into the distillation apparatus again and subjected to atmospheric distillation to distill off the solvent.

The distillation residue was cooled to room temperature. The formed precipitate was filtered off, the filtrate was transferred to an Erlenmeyer flask, and while stirring with a magnetic stirrer, 4 g of slaked lime (calcium hydroxide) slurried with water was added to adjust the pH to 5. Next, when 0.7 g of a sulfuric acid band (aluminum sulfate) was added, a blackish brown condensate was generated and settled, and the supernatant became pale yellow. The condensate was filtered off to obtain 1 L of a pale yellow filtrate.

The above filtrate was passed through a column filled with 200 ml of a hydrophobic porous resin [Diaion SP825, manufactured by Mitsubishi Chemical Co., Ltd.] for adsorption treatment. Next, water content 20 volume
The adsorbed component was eluted by passing 800 ml of ethanol of 100% through the column. The eluent contains 25 volumes of ethanol in the distillation residue.
It was distilled under reduced pressure until it became less than or equal to%.

A non-adsorbed liquid containing active ingredients such as flavones and terpenes by passing the distillation residue through a column filled with 20 ml of a hydrophobic porous resin [Diaion HP-50, manufactured by Mitsubishi Chemical Corporation]. After that, it was distilled under reduced pressure and spray-dried to obtain 15 g of a yellow powder of ginkgo biloba extract. This powder contained 24% flavone glycosides and 9% terpenes. The color tone was 0.0237 as measured by absorbance.

[Example 2] 1 kg of dried ginkgo biloba crushed to 5 to 10 mm was put into a 10 L glass column, and then 7.5 L of acetone having a water content of 20% by volume was put therein, and the mixture was heated to room temperature for 2 hours using a magnet pump. It was extracted by circulation. The extract was extracted to obtain 5 L of extract. Further, the same operation was performed twice with 5 L of acetone having a water content of 20% by volume to obtain a total of 15 L of extract.

This extract was distilled under normal pressure. Distillation was performed until the acetone content in the distillation residue reached 25% by volume, and 2 L of a blackish brown distillation residue was obtained. The distillation residue was transferred to a separating funnel, 0.5 L of hexane was added, and the mixture was shaken to perform liquid-liquid extraction to extract lipid in the hexane layer. The lower layer was again placed in the distillation apparatus and distilled under reduced pressure to remove acetone and hexane.

The distillation residue was cooled to room temperature, the precipitate formed was filtered off, and 9 g of slaked lime slurried with water was added while stirring the filtrate with a magnetic stirrer. Next, when a sulfuric acid band (1.5 g) was added, a blackish brown condensate was generated and settled, and the supernatant became pale yellow. The condensate was filtered off to obtain 2 L of filtrate. The above filtrate was passed through a column filled with 400 ml of a hydrophobic porous resin [DIAION SP825, manufactured by Mitsubishi Chemical Co., Ltd.] for adsorption treatment.

Next, 1.6 L of ethanol having a water content of 20% by volume
Was passed through a column to elute the adsorbed components. The eluate was distilled under reduced pressure to remove ethanol. Hydrophobic porous resin
[Distillation HP-50 manufactured by Mitsubishi Kagaku Co., Ltd.] was passed through a column filled with 40 ml of a distillation residual liquid obtained by distilling ethanol to obtain a non-adsorbed liquid containing active ingredients such as flavones and terpenes, This non-adsorbed liquid was distilled under reduced pressure to obtain a solid content of 20%.
Once dried, spray dried and ginkgo biloba extract yellow powder
27 g were obtained. The resulting ginkgo biloba extract powder contained 24% flavone glycosides and 8.7% terpenes. The color tone is
The absorbance was 0.0387.

Example 3 500 kg of dried ginkgo biloba crushed to 5 to 10 mm was put in a 5 L glass column, and then 5 L of ethanol having a water content of 20% by volume was put therein and subjected to circulation extraction at room temperature for 2 hours. 3 L of extract was obtained. Furthermore, the water content is 20% by volume.
The same operation was repeated twice with 5 L of ethanol to obtain a total of 13 L of extract. This extract was distilled under reduced pressure to obtain 1.3 L of a blackish brown distillation residue. The distillation residue was transferred to a separating funnel, 0.5 L of hexane was added, and the mixture was shaken to perform liquid-liquid extraction to extract lipid in the hexane layer. The lower layer was put into the distillation apparatus again and subjected to vacuum distillation to distill off the solvent.

The distillation residue was cooled to room temperature, the formed precipitate was filtered off, and the filtrate was stirred with a magnetic stirrer while slaked lime 4 g and a sulfuric acid band 1.
4 g was added and stirred for 30 minutes. The blackish brown condensate was filtered off to obtain 1 L of a pale yellow filtrate. Hydrophobic porous resin [Mitsubishi Chemical Co.,
The above filtrate was passed through a column packed with 200 ml of Diaion SP825] for adsorption treatment. Next, water content 20 volume
The adsorbed component was eluted by passing 800 ml of ethanol of 100% through the column. The eluate was distilled under reduced pressure to remove ethanol.

A distillation residual liquid obtained by distilling off ethanol was passed through a column filled with 20 ml of a hydrophobic porous resin [manufactured by Mitsubishi Chemical Co., Ltd., Diaion HP-50], and active ingredients such as flavones and terpenes were introduced. After obtaining the non-adsorbed liquid contained therein, 13 g of ginkgo biloba extract was obtained as a yellow powder by vacuum distillation and then spray drying. The resulting ginkgo biloba extract powder contained 25.3% flavone glycosides and 8.2% terpenes. The color tone was 0.022 as measured by absorbance.

In this example, the ratio of aluminum sulfate to slaked lime was set to 1.4: 4, and a double amount of aluminum sulfate of Example 1 was used, but there was no great difference in the absorbance measurement as compared with Example 1. . That is, this result shows that the more aluminum sulfate is not the better one.

Comparative Example 1 Absorbance measurement of commercially available Ginkgo biloba leaf extract and Ginkgo biloba leaf extract of the present invention (wavelength 540 nm)
The measured values are shown in Table 1, and the color tone of the appearance is shown in FIG.

[0041]

[Table 1]

From this result, the absorbance of the product of the present invention is 0.0
It is 40 or less, and the commercially available product is 0.050 or more. Therefore, in order to exert the effect of improving the color tone of the present invention, the absorbance measurement at a wavelength of 540 nm
It can be seen that it is necessary to be 0.040 or less.

Comparative Example 2 Table 2 shows the results of a comparative test of water solubility between the commercial ginkgo biloba extract and the ginkgo biloba extract of the present invention.

[0044]

[Table 2] From this result, it can be seen that the product of the present invention has improved water solubility.

[0045]

EFFECTS OF THE INVENTION The ginkgo biloba extract of the present invention is free from color components, especially brown pigment components, and has excellent water solubility. Therefore, it has a form such as foods such as health drinks, lotions, creams, emulsions and lotions. It can be used in cosmetics.

[Brief description of drawings]

FIG. 1 is a diagram showing the difference in color tone between ginkgo biloba extract and a product of the present invention.

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Claims (4)

[Claims] 1. The absorbance is 0.0 at a wavelength of 540 nm.
Ginkgo biloba extract that is 4% or less. 2. In the step of extracting ginkgo biloba extract,
A method for producing a ginkgo biloba extract, which comprises the step of treating with an inorganic coagulant. 3. The method for producing a ginkgo biloba extract according to claim 2, wherein the step of treating the inorganic coagulant is before the step of treating the hydrophobic adsorption resin. 4. The method for producing a ginkgo biloba extract according to claim 2, wherein the inorganic coagulants are aluminum sulfate and slaked lime.