Method for producing ginger extract

Abstract

To provide a method for producing a ginger extract containing a large amount of fructosyl dipeptides with a reduced amount of 6-gingerol.SOLUTION: This method for producing a ginger extract comprises the following steps (1) and (2): (1) a step for extracting ginger in water or an aqueous solution of 30% (v / v) or less ethanol; and (2) a step for bringing activated carbon into contact with the extract obtained by the step (1) in an aqueous solution of 40-60% (v / v) alcohol.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a method for producing ginger extract.

Background Art

[0002] Ginger is the rhizome of Zingiber officinale Roscoe of the family Zingiberaceae, and is a crude drug that has been used as an aromatic stomachic since ancient times. As the main components of ginger, gingerols (6-gingerol, 8-gingerol, 10-gingerol, etc.) and shogaol are known, and the extract of ginger is applied to hair growth agents and the like due to its action such as increasing blood flow.

[0003] However, since gingerols have strong skin irritation, ginger extracts substantially free of gingerols have been studied, and a method for producing an aqueous ginger extract has been reported in which ginger is extracted with 20, 50 or 70% (v / v) aqueous alcohol and then activated carbon is added to the extract for activated carbon treatment (Patent Document 1).

[0004] On the other hand, ginger contains fructosyl peptides such as Fru-Val-Tyr and Fru-Ile-Tyr, and it has been reported that the fructosyl peptides have an effect of preventing and improving wrinkles and an effect of suppressing hair growth (Patent Document 2).

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] Patent Document 2 describes the production of fructosyl dipeptides by separating and purifying ginger extract using chromatography. However, this method is complicated and has drawbacks in terms of industrial productivity. Furthermore, while the method in Patent Document 1 can reduce gingerols, particularly 6-gingerol, which are pungent and irritating components in ginger extract, it also has the problem of producing only a small amount of fructosyl dipeptides. Accordingly, the present invention relates to providing a method for producing a ginger extract containing a large amount of fructosyl dipeptide while reducing 6-gingerol. [Means for solving the problem]

[0007] The inventors of the present invention investigated various methods for extracting ginger and found that by extracting ginger with water or an aqueous ethanol solution of 30% (v / v) or less, and then contacting the extract with activated carbon in an aqueous alcohol solution of 40-60% (v / v), a ginger extract with a high amount of fructosyl dipeptide and a low amount of 6-gingerol can be obtained.

[0008] In other words, the present invention relates to the following 1) and 2). 1) Steps (1) and (2) below: (1) A step of extracting ginger with water or an aqueous solution of ethanol with a concentration of 30% (v / v) or less. (2) A step in which activated carbon is brought into contact with the extract obtained in step (1) in an aqueous alcohol solution of 40-60% (v / v). A method for producing ginger extract, including [the specified ingredient]. 2) Ginger extract containing 100 ppb or more of fructosyl dipeptide and less than 1 ppm of 6-gingerol. [Effects of the Invention]

[0009] According to the present invention, it is possible to produce a ginger extract containing a large amount of fructosyl dipeptide while reducing 6-gingerol. Therefore, the ginger extract of the present invention can be expected to exhibit the beneficial physiological functions of fructosyl dipeptide. [Brief explanation of the drawing]

[0010] [Figure 1] A diagram showing the results of component analysis of water or ethanol extract of ginger. [Figure 2] A diagram showing the results of the component analysis of ginger extract. [Modes for carrying out the invention]

[0011] The present invention provides a method for producing ginger extract, comprising the steps of (1) extracting ginger with water or an aqueous ethanol solution of 30% (v / v) or less, and (2) contacting the extract obtained in step (1) with activated carbon in an aqueous alcohol solution of 40-60% (v / v). Steps (1) and (2) will be described below.

[0012] [Step (1)] Step (1) is the step of extracting ginger with water or an aqueous solution of ethanol with a concentration of 30% (v / v) or less. In this specification, "ginger" refers to the rhizome of ginger (Zingiberaceae), sometimes with the periderm removed. Ginger is preferably heated and dried, but may also be processed by cutting, crushing, or other methods. The extraction method is not particularly limited, and conventional methods such as immersion, decoction, leaching, reflux extraction, ultrasonic extraction, microwave extraction, and stirring can be used.

[0013] Water or an aqueous solution of ethanol with a concentration of 30% (v / v) or less is used as the extraction solvent. Examples of water include tap water, distilled water, deionized water, and purified water. In this invention, "%(v / v)" means the volume percentage at 25°C.

[0014] In the present invention, from the viewpoints of anti-corrosion and increasing the concentration of fructosyl dipeptide and reducing gingerols in the extract, an aqueous ethanol solution of more than 0% (v / v) and 30% (v / v) or less is preferable as the extraction solvent, and an aqueous ethanol solution of 10% (v / v) or more and 30% (v / v) or less is more preferable.

[0015] The amount of the solvent used for extraction can be appropriately selected according to the extraction method. From the viewpoints of the yield of fructosyl dipeptide and production efficiency, 2 to 100 times by mass is preferable, and 5 to 20 times by mass is more preferable, relative to ginger (in terms of dry mass). The extraction conditions are not particularly limited as long as sufficient extraction can be performed. For example, the extraction time is preferably 0.5 hours to 10 days, and more preferably 1 day to 7 days. The extraction temperature is preferably 5 to 60°C, and more preferably 5 to 30°C. Usually, extraction is performed for a long time at a low temperature and for a short time at a high temperature.

[0016] After the extraction step, the extract can be subjected to solid-liquid separation. Examples of solid-liquid separation include filter separation using filter paper filtration, metal filters such as stainless steel, centrifugation, membrane treatment, etc., and these can be performed alone or in combination of two or more kinds. In addition, the extract can also be concentrated. The concentration method is not particularly limited, and examples include atmospheric pressure concentration method in which the solvent is evaporated at atmospheric pressure, vacuum concentration method in which the solvent is evaporated under reduced pressure, membrane concentration method in which the solvent is removed by membrane separation, etc. Further, drying may be performed as necessary. Examples of the drying method include spray drying, freeze drying, etc.

[0017] 〔Step (2)〕 This step is a step of bringing activated carbon into contact with the extract obtained in step (1) in an aqueous alcohol solution of 40 to 60% (v / v). Examples of the raw material for activated carbon include sawdust, coal, coconut shells, etc. Among these, from the viewpoint of reducing gingerols without reducing the concentration of fructosyl dipeptides, coconut shell activated carbon derived from coconut shells is preferred. Further, activated carbon activated by a gas such as steam or a chemical is preferably used. The shape of the activated carbon is not particularly limited, and examples include powder, granule, and fiber. As the activated carbon, for example, commercially available products such as Egret P (Osaka Gas Chemical Co., Ltd.) and Kuraray Coal GW (Kuraray Co., Ltd.) can be used. From the viewpoint of reducing gingerols without reducing the concentration of fructosyl dipeptides, the amount of activated carbon used is preferably 0.1 to 100 times by mass, more preferably 0.1 to 10 times by mass, and even more preferably 1 to 5 times by mass, based on the solid mass of the extract obtained in step (1). In this specification, "solid content" refers to the residue obtained by subjecting a sample to concentration under reduced pressure using a rotary evaporator, adding water, freeze-drying, and removing volatile substances.

[0018] Examples of the alcohol include monohydric, dihydric or polyhydric alcohols. Examples of the monohydric alcohol include methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, t-butanol, etc. Examples of the dihydric alcohol include alkylene glycols such as ethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butylene glycol, etc. Examples of the trihydric alcohol include glycerin. The alcohol can be used alone or in combination of two or more. From the viewpoint of reducing gingerols while leaving fructosyl dipeptides, monohydric and dihydric alcohols are preferred, ethanol and 1,3-butylene glycol are more preferred, and ethanol is even more preferred. From the viewpoint of reducing gingerols while leaving fructosyl dipeptides, the alcohol concentration of the aqueous alcohol solution in this step is 40 to 60% (v / v). For example, the concentration of the alcohol aqueous solution can be adjusted by adding and mixing alcohol and water to the extract so that the alcohol concentration in the alcohol aqueous solution falls within the above range, or by adding and mixing alcohol to the extract, and then adding water to adjust the alcohol concentration to fall within the above range.

[0019] From the viewpoint of yield and manufacturing efficiency of fructosyl dipeptides, the amount of aqueous alcohol solution used is preferably 10 to 10,000 times the mass of the solid content of the extract obtained in step (1), and more preferably 100 to 1,000 times the mass.

[0020] Methods for contacting the extract obtained in step (1) with activated carbon include, for example, batch processing, continuous processing, etc. In a batch process, for example, activated carbon can be added to an alcohol aqueous solution containing the extract, stirred to allow adsorption, and then the activated carbon can be recovered by filtration. The processing atmosphere can be air or an inert gas (nitrogen gas, argon gas, helium gas, carbon dioxide). In the case of a continuous process, for example, contact can be maintained by continuously processing using a column packed with activated carbon. The liquid flow conditions can be set as appropriate.

[0021] The contact temperature between the extract obtained in step (1) and the activated carbon is preferably 5°C to 35°C, and more preferably 10°C to 30°C, from the viewpoint of gingerol removal efficiency, fructosyl dipeptide yield, and manufacturing efficiency.

[0022] The contact time between the extract obtained in step (1) and activated carbon can be appropriately selected depending on the contact method and scale, but from the viewpoint of gingerol removal efficiency, fructosyl dipeptide yield, and manufacturing efficiency, 0.5 hours to 7 days is preferred, and 2 hours to 1 day is more preferred.

[0023] The ginger extract of the present invention can be obtained by recovering the treated liquid after contact with activated carbon, through solid-liquid separation operations such as centrifugation and filtration. The form of the ginger extract of the present invention is not particularly limited and may be solid, semi-solid, or liquid. Furthermore, the processed liquid recovered as described above can be concentrated or dried. The concentration method and drying method are as described above.

[0024] The ginger extract of the present invention has a high amount of fructosyl dipeptide and a low amount of 6-gingerol. Hereinafter, "fructosyl dipeptide" is a collective term for Fru-Val-Tyr, Fru-Ile-Tyr, Fru-Val-Phe, Fru-Ile-Val, and Fru-Val-Ile. Fru represents a fructosyl residue, Val represents a valine residue, Tyr represents a tyrosine residue, Ile represents an isoleucine residue, and Phe represents a phenylalanine residue. The fructosyl residue may be the D-form or L-form, α-form or β-form, and may be either the furanose type or the pyranose type. In solution, the α-form, β-form, furanose type, and pyranose type are interconverted, resulting in a mixture thereof. For example, in water, it becomes a mixture of β-pyranose type (67%), β-furanose type (12%), α-furanose type (15%), and α-pyranose type (6%). The stereochemistry of each amino acid residue may be either the D-form or the L-form, but the L-form is preferred. In this invention, it is sufficient to contain at least one of the five types of fructosyl dipeptides described above. The fructosyl dipeptide may also be in the form of a salt or hydrate. The salt is not particularly limited as long as it is physiologically acceptable, but examples include alkali metal salts, alkaline earth metal salts, amine salts, amino acid salts, and acid addition salts.

[0025] The fructosyl dipeptide content in the ginger extract of the present invention is preferably 100 ppb or more, and more preferably 200 ppb or more. The fructosyl dipeptide content can be measured by the method described in the examples below, and the fructosyl dipeptide content is defined based on the total amount of the five types described above.

[0026] The 6-gingerol content in the ginger extract of the present invention is preferably less than 1 ppm, more preferably less than 0.1 ppm, and even more preferably substantially absent (for example, below the detection limit of HPLC). The 6-gingerol content can be measured by the method described in the examples below.

[0027] Furthermore, the mass ratio of the fructosyl dipeptide content to the 6-gingerol content in the ginger extract of the present invention is preferably 1 or more.

[0028] The ginger extract of the present invention can be used in various fields such as pharmaceuticals, quasi-drugs, cosmetics, and foods. It is particularly suitable for use in topical skin preparations. The ginger extract of the present invention may be used alone, or it may be used in combination with various additives used in formulations such as oils, pigments, fragrances, preservatives, chelating agents, pigments, antioxidants, vitamins, minerals, sweeteners, seasonings, preservatives, binders, bulking agents, disintegrants, surfactants, lubricants, dispersants, buffers, coating agents, carriers, and diluents.

[0029] With regard to the embodiments described above, the present invention further discloses the following aspects.

[0030] <1> The following steps (1) and (2): (1) A step of extracting ginger with water or an aqueous solution of ethanol with a concentration of 30% (v / v) or less. (2) A step in which activated carbon is brought into contact with the extract obtained in step (1) in an aqueous alcohol solution of 40-60% (v / v). A method for producing ginger extract, including [the specified ingredient].

[0031] <2> Water or an aqueous solution of ethanol with a concentration of 30% (v / v) or less is preferably an aqueous solution of ethanol with a concentration of more than 0% (v / v) and 30% (v / v) or less, and more preferably an aqueous solution of ethanol with a concentration of 10% (v / v) or more and 30% (v / v) or less. <1> The manufacturing method described above. <3> The amount of activated carbon used is preferably 0.1 to 100 times the mass of the solid content of the extract obtained in step (1), more preferably 0.1 to 10 times the mass, and even more preferably 1 to 5 times the mass. <1> or <2> The manufacturing method described above. <4> The aqueous alcohol solution is preferably one or more selected from monohydric alcohols and dihydric alcohols, more preferably one or more selected from ethanol and 1,3-butylene glycol, and even more preferably ethanol. <1> ~ <3> A manufacturing method described in any of the following.

[0032] <5> Ginger extract containing 100 ppb or more of fructosyl dipeptide and less than 1 ppm of 6-gingerol.

[0033] <6> The fructosyl dipeptide content is preferably 200 ppb or more, and the 6-gingerol content is preferably less than 0.1 ppm. <5> Ginger extract as described. [Examples]

[0034] In the following examples, "%" means "%(v / v)".

[0035] <Fructosyl dipeptide analysis conditions> The sample was diluted 10-fold with ultrapure water and methanol in a 1:1 ratio, filtered, and then measured by LC-MS / MS under the following conditions. [Measurement conditions] Column: Inertsustain AQ-18 HP (3mm x 250mm, 3μm) Column temperature: 40℃ Mobile phase: A; 0.1% formic acid / H2O B;CH3CN

[0036] [Table 1]

[0037] Flow rate: 0.4mL / min Injection volume: 3μL Ionization: ESI(+) MS / MS:443.2 / 359.4Da(Fru-Val-Tyr) 457.3 / 373.1Da(Fru-Ile-Tyr) 393.1 / 309.1Da(Fru-Ile-Val) 393.2 / 309.3 (Fru-Val-Ile) 427.2 / 343.2 (Fru-Val-Phe)

[0038] <6-Gingerol Analysis Conditions> The sample was diluted 100-fold with ultrapure water and methanol in a 1:1 ratio, filtered, and then measured by HPLC under the following conditions. [Measurement conditions] Column: Inertil ODS3 (3mm x 150mm, 5μm) Column temperature: 40℃ Mobile phase: A; 0.1% formic acid / H2O B;CH3CN

[0039] [Table 2]

[0040] Flow rate: 0.4mL / min Injection volume: 5μL Detection: UV280nm

[0041] Reference example 1 50 mg of ginger (manufactured by Tochimoto Tenkaido Co., Ltd.) was extracted with 1 mL of ion-exchanged water and 10-100% ethanol aqueous solution at 25°C for 1 day, then filtered to obtain the extract. The analytical results of the extract are shown in Figure 1.

[0042] As shown in Figure 1, it was confirmed that extracts obtained by extracting ginger with water or an ethanol aqueous solution of 30% or less yielded more fructosyl dipeptides compared to extracts obtained by extracting with an ethanol aqueous solution of 40% or more.

[0043] Examples 1-6 10g of ginger (manufactured by Tochimoto Tenkaido Co., Ltd.) was extracted in 200mL of 10% ethanol aqueous solution at 25°C for 3 days, then filtered to obtain the extract. Each of the obtained extracts was concentrated to 4 mL and redissolved in 4 mL of each solvent. 500 μL of each redissolved solution was taken, 10 mg of activated carbon (Shirasagi P, Osaka Gas Chemical Co., Ltd.) was added to each, and after 1 hour, the solution was filtered to obtain ginger extract (Table 3). The analytical results of the ginger extract are shown in Figure 2.

[0044] Comparative Example 1 10 g of ginger (manufactured by Tochimoto Tenkaido Co., Ltd.) was extracted in 200 mL of 20% ethanol aqueous solution at 25°C for 3 days, and then filtered to obtain the extract. 10 mg of activated carbon (Shirasagi P) was added to 500 μL of this extract, and after 1 hour, it was filtered to obtain ginger extract (Table 3). The analytical results of the ginger extract are shown in Figure 2.

[0045] Comparative Example 2 Ginger extract was obtained by the same procedure as in Comparative Example 1, except that a 50% 1,3-butylene glycol aqueous solution was used as the extraction solvent (Table 3). The analytical results of the ginger extract are shown in Figure 2.

[0046] Comparative Example 3 Ginger extract was obtained by the same procedure as in Comparative Example 1, except that a 70% 1,3-butylene glycol aqueous solution was used as the extraction solvent (Table 3). The analytical results of the ginger extract are shown in Figure 2.

[0047] [Table 3]

[0048] As shown in Figure 2, it was confirmed that by extracting ginger with a low-concentration ethanol aqueous solution and then contacting the extract with activated carbon in a 40-60% alcohol aqueous solution, a ginger extract containing a large amount of fructosyl dipeptide but substantially no 6-gingerol could be obtained. In contrast, the ginger extracts of Comparative Examples 1-3, which were treated with activated carbon in a 20% ethanol extract or a 50% or 70% 1,3-butylene glycol extract, contained substantially no 6-gingerol or only a small amount of 6-gingerol, but also a small amount of fructosyl dipeptide.

Claims

1. The following steps (1) and (2): (1) A step of extracting ginger with water or an aqueous solution of ethanol with a concentration of 30% (v / v) or less. (2) A step of contacting activated carbon with the extract obtained in step (1) in a 40-60% (v / v) aqueous alcohol solution. A method for producing ginger extract, which includes: The aforementioned alcohol aqueous solution is an ethanol aqueous solution or a 1,3-butylene glycol aqueous solution. A method for producing the ginger extract, wherein the ginger extract contains 100 ppb or more of fructosyl dipeptide and has a 6-gingerol content of less than 1 ppm.

2. A method for producing ginger extract according to claim 1, wherein the amount of activated carbon used is 0.1 to 100 times the mass of the solid content of the extract obtained in step (1).

3. A method for producing a topical skin preparation containing ginger extract produced by the manufacturing method described in Claim 1 or 2.

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