High-purity shell ginger extract and method for producing the same

Abstract

To provide a method for producing an Alpinia speciosa extract having higher purity of α-pyrone as compared with conventional arts.SOLUTION: A method for producing an Alpinia speciosa extract includes the steps of: subjecting a dried product of Alpinia speciosa to extraction treatment using a dehydrokawain soluble solvent, to obtain an Alpinia speciosa crude extract; and subjecting the Alpinia speciosa crude extract to water-adding treatment and alkali treatment or water-adding treatment, alkali treatment and salting-out, to obtain an Alpinia speciosa extract.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a highly pure shell ginger extract and a method for producing the same. [Background technology]

[0002] Shell ginger leaf extract is known as one of the functional ingredients in functional foods. The functionality of shell ginger leaf extract is said to be its skin-beautifying effect, helping to moisturize the skin of people who tend to have dry skin.

[0003] The index components in Alpinia zerumbet leaf extract are two types of α-pyrones, dihydro-5,6-dehydrokawain and 5,6-dehydrokawain. It is believed that Alpinia zerumbet leaf extract exerts skin-beautifying effects through the promotion of fibroblast proliferation, collagen production promotion, and collagen-degrading enzyme activity inhibition, due to the inclusion of these α-pyrones.

[0004] Known methods for producing shell ginger leaf extract include an ethanol extraction process in which shell ginger leaves are added to aqueous ethanol, and a hot water extraction process in which shell ginger leaves are added to water and heated (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2002-302453 Summary of the Invention [Problem to be solved by the invention]

[0006] However, the method described in Patent Document 1 in which shell ginger leaves are subjected to ethanol extraction or hot water extraction has the problem that the resulting extract contains sugars, flavonoids, etc. in addition to α-pyrones, and the purity of the α-pyrones is low.

[0007] Therefore, the problem that the present invention aims to solve is to provide a method for producing an extract of shell ginger having a higher purity of α-pyrones than the method described in Patent Document 1. [Means for solving the problem]

[0008] The present inventors conducted extensive research to solve the above-mentioned problems, and as a result, they focused on the state of the shell ginger used in the extraction process and further processing after the extraction process. Then, through repeated trial and error, such as using shell ginger in various states and applying various processes to the extracted material, they surprisingly discovered that a shell ginger extract containing α-pyrones at a high purity can be obtained by performing a solvent extraction process using dried shell ginger, and then subjecting the resulting solvent extraction product to a water treatment and an alkali treatment. As a result, the present inventors succeeded in creating a method for producing a shell ginger extract containing α-pyrones at a high purity from shell ginger. The present invention was completed based on these findings and successful examples.

[0009] Therefore, according to the present invention, the following methods and shell ginger extracts are provided. [1] A step of obtaining a crude shell ginger extract by subjecting a dried shell ginger product to an extraction treatment using a dehydrokawain-soluble solvent; a step of obtaining a shell ginger extract by subjecting the shell ginger crude extract to a water treatment and an alkali treatment; A method for producing a shell ginger extract, comprising: [2] A step of obtaining a crude shell ginger extract by subjecting the shell ginger dried product to an extraction treatment using a dehydrokawain-soluble solvent; a step of obtaining a shell ginger extract by subjecting the shell ginger crude extract to a water treatment, an alkali treatment and salting out; A method for producing a shell ginger extract, comprising: [3] The method according to any one of [1] to [2], wherein the crude extract of the moonwort is obtained by subjecting the extract obtained by the extraction process to a solid-liquid separation process and / or a concentration process. [4] The method according to any one of [2] to [3], wherein the salting out is carried out using at least one sugar selected from the group consisting of glucose, sucrose, and maltose. [5] The method according to any one of [1] to [4], wherein the dehydrokawain-soluble solvent is 30% (v / v) to 90% (v / v) aqueous ethanol. [6] The method according to any one of [1] to [5], wherein the alkali treatment is an alkali treatment using sodium hydroxide at a final concentration of 0.5% (w / v) to 6% (w / v). [7] The method according to any one of [1] to [6], wherein the shell ginger extract has a total content of dihydro-5,6-dehydrokawain and 5,6-dehydrokawain of 80% (w / w) or more. [8] The method described in any one of [1] to [7], wherein the shell ginger extract has a dihydro-5,6-dehydrokawain content of 70% (w / w) or more and / or a 5,6-dehydrokawain content of 10% (w / w) or more. [9] The method according to any one of [1] to [8], wherein the shell ginger extract is a solid shell ginger extract.

[10] A shell ginger extract, in which the total content of dihydro-5,6-dehydrokawain and 5,6-dehydrokawain is 80% (w / w) or more, and the dihydro-5,6-dehydrokawain and 5,6-dehydrokawain are derived from shell ginger.

[11] The shell ginger extract described in

[10] , wherein the content of dihydro-5,6-dehydrokawain is 80% (w / w) or more and / or the content of 5,6-dehydrokawain is 10% (w / w) or more. [Effects of the Invention]

[0010] According to a method of one aspect of the present invention, a shell ginger extract containing α-pyrones such as dihydro-5,6-dehydrokawain and 5,6-dehydrokawain at high purity can be produced using shell ginger as a raw material. Furthermore, since the processing procedures employed in the method of the present invention are simple and safe, the method of one aspect of the present invention makes it possible to produce shell ginger extract in large quantities on an industrial scale. Therefore, the method of one aspect of the present invention is a method for producing a high-purity shell ginger extract that is industrially practical, rapid, safe, and economical.

[0011] The shell ginger extract obtained by the method of one embodiment of the present invention can be in solid form, so it can be processed into a variety of dosage forms, can be added to various foods, beverages, and cosmetics, and has excellent shelf life, so it can be widely distributed. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a flow chart showing an outline of the method for producing a high-purity shell ginger extract using shell ginger flowers as a raw material according to Example 1, as described in the Examples below. [Figure 2] FIG. 2 is a flow chart showing an outline of the method for producing a high-purity shell ginger extract using shell ginger flowers as a raw material according to Example 2, as described in the Examples below. [Figure 3] FIG. 3 is a flow chart showing an outline of the method for producing a high-purity shell ginger extract using shell ginger flowers as a raw material in Example 3, as described in the Examples below. [Figure 4] FIG. 4 is a flow chart showing an outline of the method for producing a high-purity shell ginger extract using shell ginger leaves as a raw material according to Example 4, as described in the Examples below. DETAILED DESCRIPTION OF THE INVENTION

[0013] Each aspect of the present invention will be described in detail below, but the present invention can take various forms as long as it achieves its object.

[0014] Unless otherwise specified, each term in this specification is used in the sense commonly used by those skilled in the art of food, cosmetics, etc., and should not be construed as having an unduly restrictive meaning. Furthermore, the speculations and theories made in this specification are based on the inventors' knowledge and experience to date, and therefore the present invention is not limited solely to such speculations and theories.

[0015] The term "and / or" means any one or any or all combinations of two or more of the associated listed items. "Content" is synonymous with concentration and amount used (amount added), and refers to the ratio of the amount of a component to the total amount of shell ginger extract. However, the total amount of component content will not exceed 100%. "Purity" is also used synonymously with content. In other words, a highly pure component means a component that occupies a high proportion in shell ginger extract. The unit "vol%" is synonymous with "%(v / v)" and "volume %". The unit "wt%" is synonymous with "%(w / w)" and "mass %". The unit "%(w / v)" is synonymous with "mass volume %". The "to" in a numerical range includes the preceding and following numerical values; for example, "0% to 100%" means a range greater than or equal to 0% and less than or equal to 100%. "More than" and "less than" mean the lower and upper limits, respectively, excluding the preceding numerical value; for example, "more than 1" means a numerical value greater than 1, and "less than 100" means a numerical value less than 100. "Comprising" means that elements other than those explicitly stated as being included can be added (same meaning as "comprising at least"), but also encompasses "consisting of" and "consisting essentially of." That is, "comprising" can mean including the explicitly stated elements and any one or more elements, consisting of the explicitly stated elements, or consisting essentially of the explicitly stated elements. Elements include limitations such as ingredients, steps, conditions, and parameters.

[0016] The number of digits in an integer value matches the number of significant digits. For example, 1 has one significant digit, and 10 has two significant digits. Also, the number of digits after the decimal point matches the number of significant digits in a decimal value. For example, 0.1 has one significant digit, and 0.10 has two significant digits.

[0017] In this specification, dihydro-5,6-dehydrokawain is sometimes referred to as "DDK" and 5,6-dehydrokawain is sometimes referred to as "DK." Furthermore, "dehydrokawain" is a general term for either DDK or DK, or a combination of DDK and DK. DDK and DK are compounds having the following structures: [ka]

[0018] A method according to one aspect of the present invention is a method for producing a shell ginger extract containing dehydrokawain at a high purity. The method according to one aspect of the present invention is characterized in that a shell ginger raw material is subjected to a solvent extraction treatment, a water treatment, and an alkali treatment, or a solvent extraction treatment, a water treatment, an alkali treatment, and salting out, thereby obtaining a dehydrokawain-containing substance as an shell ginger extract.

[0019] A first embodiment of the method of the present invention comprises the following steps (1) and (2). (1) A step of obtaining a crude shell ginger extract by subjecting a dried shell ginger to an extraction treatment using a dehydrokawain-soluble solvent. (2) A process of obtaining a shell ginger extract by subjecting the shell ginger crude extract to a water treatment and an alkali treatment.

[0020] The second embodiment of the method of the present invention comprises the following steps (1) and (2)'. (1) A step of obtaining a crude shell ginger extract by subjecting a dried shell ginger to an extraction treatment using a dehydrokawain-soluble solvent. (2)' A process of obtaining a shell ginger extract by subjecting the shell ginger crude extract to water treatment, alkali treatment and salting out.

[0021] In step (1), a dried shell ginger plant is subjected to extraction treatment using a dehydrokawain-soluble solvent to obtain a shell ginger crude extract.

[0022] Shell ginger ( Alpinia zerumbet ), also known as Getto, is an evergreen perennial plant known to grow wild from the southern tip of Kyushu to Okinawa Prefecture, from Taiwan to southern China, Southeast Asia, and India. It is known to promote fibroblast proliferation, collagen production, and inhibit collagen-degrading enzyme activity, and is consumed in the hope of improving skin through these effects. Furthermore, it is a natural plant that has been consumed by humans for a long time and is highly safe.

[0023] The parts of the shell ginger used are not particularly limited as long as they contain dehydrokawain, and examples include leaves, flowers, roots, stems, fruits, seeds, etc., but leaves, flowers, and roots, which contain a large amount of dehydrokawain, are preferred. The shell ginger may be a single part such as leaves, flowers, or roots, or a combination of two or more of these parts.

[0024] When shell ginger is used in its fresh state after harvesting, the efficiency of the extraction process tends to decrease. Therefore, a dried shell ginger product obtained by drying shell ginger is used as the shell ginger. The drying process is not particularly limited, and examples include a process in which the mass of the shell ginger after drying (dry mass) is approximately 1 / 100 to 9 / 10 of the mass before drying (wet mass). The drying process may be performed by any method known to those skilled in the art, such as hot air drying, vacuum drying, low-temperature vacuum drying, high-pressure steam drying, electromagnetic wave drying, freeze-drying, or air drying. The moisture content of the dried shell ginger product is not particularly limited, but is preferably 20% or less, and more preferably 10% or less.

[0025] From the viewpoint of increasing the contact area with the solvent and efficiently carrying out the extraction process, the shell ginger is preferably in a state of being chopped, crushed, pulverized, or ground. The method for chopping, crushing, pulverizing, or pulverizing the shell ginger is not particularly limited, and examples thereof include methods using a cutter, slicer, cutting machine, crusher, blender, mixer, mill, grinder, kneader, mortar, stone mill, etc.

[0026] When using roots, stems, seeds, etc. as shell ginger, the dried shell ginger used in step (1) is preferably a powdered dried shell ginger product in order to improve the efficiency of the extraction process. When obtaining a powdered dried shell ginger product, the drying process and the crushing process may be carried out simultaneously, or one of the processes may be carried out first and then the other, but for ease of operation, it is preferable to carry out the drying process first and then the crushing process.

[0027] The dehydrokawain-soluble solvent is not particularly limited as long as it can dissolve dehydrokawain, and examples thereof include solvents that readily dissolve dehydrokawain, specifically water; lower alcohols such as methanol, ethanol, propanol, isopropanol, and butanol; lower esters such as ethyl acetate and methyl acetate; dimethyl sulfoxide, acetonitrile, acetone, hexane, glycerin, and propylene glycol. The dehydrokawain-soluble solvent may be one of these solvents alone or a combination of two or more of these solvents.

[0028] From the viewpoints of extraction efficiency, safety, and industrialization, the dehydrokawain-soluble solvent is preferably water or a lower alcohol, more preferably water, ethanol, or methanol, even more preferably water and ethanol, and even more preferably aqueous ethanol, which is a mixed solvent of water and ethanol.

[0029] When aqueous ethanol is used as the dehydrokawain-soluble solvent, the ethanol content is preferably 20 vol% to 100 vol%, and from the viewpoints of good extraction efficiency, safety, and industrialization, more preferably 30 vol% to 90 vol%, even more preferably 40 vol% to 80 vol%, and even more preferably 50 vol% to 70 vol%. However, if the ethanol content in the aqueous ethanol is less than 20 vol%, it may be difficult to efficiently extract dehydrokawain.

[0030] The extraction conditions are not particularly limited as long as they are suitable for dissolving the dehydrokawain in the dried shell ginger in the solvent, and the type and amount of dehydrokawain-soluble solvent used can be appropriately determined depending on the state of the dried shell ginger (e.g., moisture content) and amount used, but examples include immersing the dried shell ginger for a predetermined period of time in a dehydrokawain-soluble solvent that is 1 to 20 times, preferably 2 to 15 times, and more preferably 3 to 10 times the volume of the dried shell ginger. In such extraction procedures, stirring, heating, etc. may be performed as necessary to increase extraction efficiency.

[0031] Specific conditions for the extraction process include, but are not limited to, placing dried shell ginger and 50 vol% to 70 vol% aqueous ethanol in a container at a volume 3 to 10 times the volume of the dried shell ginger, and leaving or stirring at 10°C to 40°C, preferably room temperature (20°C to 30°C), for several hours to several days, preferably 12 hours to 10 days.

[0032] By subjecting the dried shell ginger to the above-mentioned extraction treatment, an extract and an extraction residue can be obtained. By performing a solid-liquid separation treatment after the extraction treatment, the extract and the extraction residue can be separated efficiently. The solid-liquid separation means is not particularly limited, and known solid-liquid separation means such as filtration and centrifugation can be used.

[0033] When an organic solvent is used as the dehydrokawain-soluble solvent, the extract is preferably subjected to a concentration treatment for the purpose of volatilizing the organic solvent. The concentration treatment is not particularly limited as long as it is a commonly known treatment for removing the organic solvent and further reducing the volume of the liquid, and examples include placing the extract under reduced pressure at room temperature, placing the extract under low-temperature vacuum, heating, and freeze-drying. The degree of concentration is not particularly limited, and the volume may be reduced to, for example, about 1 / 1,000 to 1 / 10, preferably 1 / 100 to 1 / 10, or the liquid component may be volatilized until the extract is in a solid dry state.

[0034] The extraction treatment may be performed once, but to increase the recovery rate of DDK and / or DK, the extraction treatment is preferably performed twice or more, and from the viewpoint of workload and economy, two extraction treatments are more preferable. For example, step (1) may be performed by subjecting the dried shell ginger to a first extraction treatment to obtain a first extract and a first extraction residue, and then subjecting the obtained first extraction residue to a second extraction treatment to obtain a second extract and a second extraction residue.

[0035] When the extraction treatment is performed two or more times, each extraction treatment may be performed under the same conditions or under different conditions. The extracts obtained in each extraction treatment can be combined and used as a single shell ginger crude extract in the next step. When the extracts are subjected to solid-liquid separation treatment and / or concentration treatment, each extract may be subjected to solid-liquid separation treatment and / or concentration treatment, or the combined extracts may be subjected to solid-liquid separation treatment and / or concentration treatment.

[0036] As described above, a crude extract of shell ginger is obtained by subjecting the dried shell ginger to extraction treatment, preferably by subjecting it to two or more extraction treatments, more preferably by subjecting each extract liquid to solid-liquid separation treatment and concentration treatment after two extraction treatments and combining them.

[0037] The content of dehydrokawain in the shell ginger crude extract is not particularly limited, but is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, even more preferably 1.0% by mass or more, and even more preferably 2.0% by mass or more.

[0038] In step (2), the shell ginger extract obtained in step (1) is subjected to a water treatment and an alkali treatment to obtain a shell ginger extract. By subjecting the shell ginger crude extract to a water treatment and an alkali treatment, water-soluble components and impurities such as fatty acids in the shell ginger crude extract can be removed, and a shell ginger extract containing a high concentration of dehydrokawain can be obtained as an insoluble matter (precipitate).

[0039] The conditions for the hydration treatment are not particularly limited as long as water is added to the shell ginger crude extract, and can be carried out, for example, by contacting the shell ginger crude extract with 1 to 20 times the volume of water, preferably 2 to 15 times the volume of water, more preferably 4 to 10 times the volume of water, and even more preferably 6 to 8 times the volume of water relative to the volume of the shell ginger crude extract. The temperature and time for this treatment are not particularly limited, and can be, for example, 10°C to 30°C for a few seconds to a few minutes to a few hours.

[0040] The alkali treatment is not particularly limited as long as it is carried out under conditions that decompose impurities in the shell ginger crude extract and allow dehydrokawain to precipitate as an insoluble component. For example, the treatment can be carried out by stirring and / or leaving an aqueous solution containing the shell ginger crude extract and an alkaline component at 10°C to 30°C, preferably at room temperature, for several hours to several days.

[0041] The alkaline component used in the alkaline treatment is not particularly limited as long as it decomposes impurities in the shell ginger crude extract and does not dissolve dehydrokawain, and examples thereof include sodium hydroxide, potassium hydroxide, and calcium hydroxide, with sodium hydroxide being preferred because it is a strong alkali and is economical.

[0042] The amount of alkaline component used in the alkaline treatment is not particularly limited as long as it is an amount that can precipitate dehydrokawain, but for example, if the alkaline component is sodium hydroxide, it is an amount that will result in a final concentration of 0.1% (w / v) to 10% (w / v), preferably 0.5% (w / v) to 8% (w / v), and more preferably 0.5% (w / v) to 6% (w / v).The amount of alkaline component used in the alkaline treatment is preferably an amount that will result in a pH on the alkaline side, preferably 12 to 14, and more preferably around 14, using pH as an index.

[0043] In step (2), the water treatment and alkali treatment may be carried out simultaneously by using an alkaline aqueous solution. For example, step (2) can be carried out by adding the shell ginger crude extract to an aqueous solution of sodium hydroxide dissolved in water, adjusting the amount of water to 5 to 10 times the volume of the shell ginger crude extract, stirring at 10 to 30°C, preferably at room temperature, for several hours to several days, preferably 1 to 24 hours, and then leaving to stand for several hours to several days, preferably 10 hours to 7 days.

[0044] In step (2)', in addition to the water treatment and alkali treatment, salting out is carried out. By carrying out salting out, dehydrokawain can be efficiently precipitated. The salting out can be carried out under any conditions that allow the precipitation of dehydrokawain. For example, the salting out can be carried out by stirring and / or leaving an aqueous solution containing the shell ginger crude extract and salts at 10°C to 30°C, preferably at room temperature, for several hours to several days.

[0045] The salts used in salting out are not particularly limited as long as they are water-soluble substances with a higher hydration power than dehydrokawain, but examples include organic salts and inorganic salts. From the standpoint of corrosiveness and safety, sugars such as glucose, sucrose, and maltose are preferred, and glucose is more preferred.

[0046] The amount of salt used in salting out is not particularly limited as long as it is an amount that allows dehydrokawain to precipitate as a solid. For example, if the salt is glucose, the amount is such that the final concentration is 0.1% (w / v) to 10% (w / v), preferably 0.5% (w / v) to 5% (w / v), and more preferably 0.5% (w / v) to 2% (w / v).

[0047] In step (2)', the water treatment, alkali treatment, and salting out may be carried out sequentially, or two or three of these treatments may be carried out simultaneously. For example, step (2)' can be carried out by adding the shell ginger crude extract to an aqueous solution prepared by dissolving sodium hydroxide and salts in water, and then adjusting the amount of water so that the volume is 5 to 10 times the volume of the shell ginger crude extract, stirring at 10°C to 30°C, preferably at room temperature, for several hours to several days, preferably 1 hour to 24 hours, and then leaving to stand for several hours to several days, preferably 10 hours to 7 days.

[0048] Steps (2) and (2)' can be performed once to obtain a shell ginger extract containing highly pure dehydrokawain, without the need for multiple steps, but they may be performed multiple times. The shell ginger extract can be obtained as a precipitate in a solid form, specifically in a powder form. The obtained aqueous solution containing the powdered shell ginger extract can be subjected to solid-liquid separation and / or drying treatment to efficiently recover the powdered shell ginger extract. When the shell ginger extract is to be used, for example, as a raw material for an oral composition or an external composition, it is preferable to wash it with water or the like.

[0049] The content of dehydrokawain in the shell ginger extract obtained by the method of one embodiment of the present invention is not particularly limited, but for example, it is preferably 70 wt% or more, more preferably 80 wt% or more, even more preferably 90 wt% or more, and even more preferably 95 wt% or more, based on the dry mass of the shell ginger extract. In addition, the recovery rate of dehydrokawain in the shell ginger extract is, for example, preferably 30% or more, more preferably 40% or more, even more preferably 80% or more, and even more preferably 90% or more, based on the content of dehydrokawain in the shell ginger crude extract. In addition, the upper limits of these are not particularly limited, but are typically 100 wt% and 100%, respectively.

[0050] The DDK and DK content varies depending on the part of the shell ginger plant. When shell ginger flowers are used, shell ginger extract containing both DDK and DK is obtained, while when shell ginger leaves are used, shell ginger extract containing DDK tends to be obtained.

[0051] When shell ginger flowers are used, the DDK content in the shell ginger extract is, for example, preferably 60 wt% or more, more preferably 70 wt% or more, and even more preferably 80 wt% or more, based on the dry mass of the shell ginger extract. Furthermore, the recovery rate of DDK in the shell ginger extract in this case is, for example, preferably 30% or more, more preferably 40% or more, even more preferably 80% or more, and even more preferably 90% or more, based on the DDK content in the shell ginger crude extract. While these upper limits are not particularly limited, they are typically 100 wt% and 100%, respectively.

[0052] When using shell ginger flowers, the DK content in shell ginger extract is, for example, preferably 5 wt% or more, more preferably 10 wt% or more, and even more preferably 12 wt% or more, based on the dry mass of shell ginger extract.In addition, the DK recovery rate in shell ginger extract in this case is, for example, preferably 10% or more, more preferably 20% or more, even more preferably 40% or more, and even more preferably 60% or more, based on the DK content in shell ginger crude extract.In addition, these upper limits are not particularly limited, but are typically 100 wt% and 100%, respectively.

[0053] When using shell ginger leaves, the DDK content in the shell ginger extract is, for example, preferably 60 wt% or more, more preferably 70 wt% or more, even more preferably 80 wt% or more, and even more preferably 90 wt% or more, based on the dry mass of the shell ginger extract. The recovery rate of DDK in the shell ginger extract in this case is, for example, preferably 30% or more, more preferably 40% or more, even more preferably 80% or more, and even more preferably 90% or more, based on the DDK content in the shell ginger crude extract. While these upper limits are not particularly limited, they are typically 100 wt% and 100%, respectively. The DK content in the shell ginger extract in this case is 1 wt% or less.

[0054] The confirmation and quantification of dehydrokawain contained in the shell ginger extract can be carried out by high performance liquid chromatography (HPLC) as described in the Examples below.

[0055] In the method of one aspect of the present invention, various steps or operations can be added before, after, or between the steps described above, as long as the object of the present invention can be achieved.

[0056] Below, as a specific embodiment of the present invention, a method for producing a shell ginger extract containing dehydrokawain using dried shell ginger flowers as a raw material will be described, but the method of one embodiment of the present invention is not limited to the following.

[0057] Shell ginger flowers harvested around the time of flowering (May to July) are subjected to low-temperature vacuum drying to dry them to a moisture content of 10% or less. A predetermined amount of dried shell ginger flowers is added to 50% to 70% aqueous ethanol, which is 3 to 10 times the volume of the dried shell ginger flowers, and the mixture is left to stand at room temperature for 12 hours to 10 days to perform an extraction process. The resulting extract is filtered to remove the shell ginger residue, and the resulting filtrate is concentrated under reduced pressure to obtain a first shell ginger crude extract. The shell ginger residue is then subjected to a similar extraction process to obtain a second shell ginger crude extract. The first shell ginger crude extract and the second shell ginger crude extract are mixed and used in the following process.

[0058] Next, an aqueous solution containing sodium hydroxide and glucose is added to the obtained shell ginger extract, and water is added to a volume 5 to 10 times that of the shell ginger crude extract. The final sodium hydroxide concentration in the obtained aqueous solution is 0.5% (w / v) to 6% (w / v), and the final glucose concentration is 0.5% (w / v) to 2% (w / v). The obtained aqueous solution is then stirred at room temperature for 1 to 24 hours, and then allowed to stand for 10 hours to 5 days to obtain a shell ginger extract as a precipitate. The obtained shell ginger extract is subjected to filtration and freeze-drying to obtain a powdered shell ginger extract. The dehydrokawain content of the obtained shell ginger extract can be 90 wt% or more based on the dry mass of the shell ginger extract.

[0059] The shell ginger extract produced by the method of one aspect of the present invention can be included in the present invention as another aspect. The shell ginger extract of the present invention is characterized in that the total content of DDK and / or DK is a predetermined amount, and the DDK and / or DK contained therein is derived from the shell ginger, which is the raw material.

[0060] In one embodiment of the shell ginger extract of the present invention, the total content of DDK and DK is, for example, 80 wt% or more, preferably 90 wt% or more, and more preferably 95 wt% or more. The upper limit of the content is not particularly limited, and is typically 100 wt%.

[0061] The shell ginger extract of one embodiment of the present invention preferably has a DDK content of 70 wt% or more, more preferably 80 wt% or more, and even more preferably 90 wt% or more, based on the dry mass of the shell ginger extract. The shell ginger extract of one embodiment of the present invention preferably has a DK content of 5 wt% or more, more preferably 10 wt% or more, and even more preferably 12 wt% or more, based on the dry mass of the shell ginger extract. However, although the shell ginger extract of one embodiment of the present invention preferably contains both DDK and DK, it is sufficient if it contains either DDK or DK.

[0062] The DDK and DK contained in the shell ginger extract of one embodiment of the present invention are characterized in that both are derived from the shell ginger plant, which is the raw material. In other words, the shell ginger extract of one embodiment of the present invention is characterized in that it does not contain DDK or DK obtained by extraction or synthesis of natural products other than shell ginger.

[0063] The uses of the shell ginger extract of one embodiment of the present invention are not particularly limited, and for example, it can be used as a raw material for various compositions such as oral compositions such as food and beverages and pharmaceuticals, and topical compositions such as cosmetics, or as the composition itself, in anticipation of the pharmacological effects of dehydrokawain.

[0064] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples, and the present invention can take various forms as long as the object of the present invention can be achieved. [Example]

[0065] [Quantitative determination of shell ginger extract] The contents (mg) of dihydro-5,6-dehydrokawain (DDK) and 5,6-dehydrokawain (DK) were measured by HPLC using a COSMOSIL 5C18-AR-2 column and MeOH:HO (60:40-100:0) as the mobile phase at a flow rate of 1 ml / min. DDK had a retention time of approximately 12 minutes at a wavelength of 278.0 nm, and DK had a retention time of approximately 17 minutes at a wavelength of 318 nm. The calibration curve method was used to measure this.

[0066] [Example 1. Production of high-purity shell ginger extract using shell ginger flowers (1)] As Example 1, Figure 1 shows a flow chart outlining the production method for high-purity shell ginger extract using shell ginger flowers as the raw material, carried out on a 100 g scale using a system of 4% (w / v) sodium hydroxide and 1% (w / v) glucose.

[0067] Alpinia sieboldii flowers were subjected to low-temperature vacuum drying at 40°C for 5 hours to obtain dried flowers (moisture content 3%-8%). 100.0 g of dried flowers were placed in 500 mL of 60% (v / v) aqueous ethanol and subjected to ethanol extraction by leaving the mixture at room temperature for 1 day. The extract was then filtered using a filter (pore size 5 μm) to obtain 224.1 g of filtrate (1) and 325.9 g of residue (1). The entire amount of filtrate (1) was subjected to vacuum concentration to obtain 7 g of crude extract (1) as the first extract. The crude extract (1) contained 448.6 mg of dihydroxybenzoate and 120.3 mg of dihydroxybenzoate.

[0068] The residue (1) was placed in 500 mL of 60% (v / v) aqueous ethanol and left to stand at room temperature for 1 day for ethanol extraction. This was followed by filtration using a filter (pore size 5 μm) to obtain 467.1 g of filtrate (2). The entire filtrate (2) was concentrated under reduced pressure to obtain 6 g of crude extract (2) as a second extract. The crude extract (2) contained 375.5 mg of DDK and 105.4 mg of DK.

[0069] An aqueous solution containing 4.0 g of sodium hydroxide and 1.0 g of glucose was added to crude extract (1+2), which was a combination of the obtained crude extract (1) and crude extract (2). Water was then added to bring the total volume to 100 mL. The resulting solution (pH 14) was stirred (150 rpm) at room temperature for 5 hours, then allowed to stand for 19 hours for alkali treatment and salting out, and then centrifuged (2600 x g, 4,000 rpm, 1 minute). The resulting precipitate was freeze-dried to obtain 1,012.6 mg of powdered shell ginger extract.

[0070] The obtained shell ginger extract contained 843.5 mg of DDK (purity 83.3%) and 155.3 mg of DK (purity 15.3%). Based on the amounts of DDK and DK contained in the crude extract (1 + 2), the recovery rate of DDK in the shell ginger extract was 103%, and the recovery rate of DK was 70%.

[0071] [Example 2. Production of high-purity shell ginger extract using shell ginger flowers (2)] As Example 2, Figure 2 shows a flow chart outlining the production method for high-purity shell ginger extract using shell ginger flowers as the raw material, carried out on a 38.0 kg scale using a system of 4% (w / v) sodium hydroxide and 1% (w / v) glucose.

[0072] Alpinia sieboldii flowers were subjected to low-temperature vacuum drying at 40°C for 5 hours to obtain dried flowers (moisture content 3%-8%). 38.0 kg of dried flowers were placed in 180 L of 60% (v / v) aqueous ethanol and subjected to an ethanol extraction process by leaving the mixture at room temperature for 7 days. The mixture was then filtered using a filter (pore size 20 μm) to obtain approximately 120 L of filtrate (1) and filtration residue (1). The entire filtrate (1) was subjected to low-temperature vacuum drying at 40°C for 5 hours to obtain crude extract (1) as the first extract. The DDK and DK in crude extract (1) were 200 g and 62 g, respectively.

[0073] The residue (1) was placed in 180 L of 60% (v / v) aqueous ethanol and left to stand at room temperature for 7 days for ethanol extraction. The mixture was then filtered through a filter (pore size 20 μm) to obtain approximately 150 L of filtrate (2). The entire filtrate (2) was subjected to low-temperature vacuum drying at 40°C for 6 hours to obtain crude extract (2) as a second extract. The crude extract (2) contained 87 g of DDK and 27 g of DK.

[0074] The total amounts of crude extract (1) and crude extract (2) were combined to obtain crude extract (1+2), which was then subjected to low-temperature vacuum drying.

[0075] An aqueous solution containing 1.5 kg of sodium hydroxide and 350 g of glucose was added to the extract (1+2), and water was added to bring the total volume to 38 L. The resulting solution (pH 14) was stirred (150 rpm) at room temperature for 15 hours, then subjected to alkali treatment by leaving it to stand for 3 days, and then subjected to centrifugation (2600 x g, 4,000 rpm, 10 minutes). The resulting precipitate was freeze-dried to obtain 189.5 g of powdered shell ginger extract.

[0076] The obtained shell ginger extract contained 134.5 g of DDK (purity 71.0%) and 25.9 g of DK (purity 13.7%). Based on the amounts of DDK and DK contained in the crude extract (1 + 2), the recovery rate of DDK in the shell ginger extract was 47%, and the recovery rate of DK was 29%.

[0077] [Example 3. Production of high-purity shell ginger extract using shell ginger flowers as raw materials (3)] As Example 3, Figure 3 shows a flow chart outlining the production method for high-purity shell ginger extract using shell ginger flowers as the raw material, carried out on a 100 g scale with 1% (w / v) sodium hydroxide and no glucose used.

[0078] The shell ginger flowers were subjected to low-temperature vacuum drying at 40°C for 5 hours to obtain dried flowers (moisture content 3% to 8%). 100.0 g of the dried flowers were placed in 500 mL of 60% (v / v) aqueous ethanol and subjected to an ethanol extraction process by leaving the mixture at room temperature for 1 day. The mixture was then filtered using a filter (pore size 5 μm) to obtain filtrate (1) and filtration residue (1).

[0079] The filtration residue (1) was placed in 500 mL of 60% (v / v) aqueous ethanol and subjected to an ethanol extraction treatment by leaving it to stand at room temperature for 1 day, and then subjected to a filtration treatment using a filter (pore size 5 μm) to obtain a filtrate (2).

[0080] The filtrate (1) and the filtrate (2) were combined to give 714.9 g of filtrate (1+2), which was then concentrated under reduced pressure to give 13 g of crude extract (1+2). The DDK content in the crude extract (1+2) was 838.9 mg, and the DK content was 252.3 mg.

[0081] An aqueous solution containing 1.0 g of sodium hydroxide was added to the obtained crude extract (1+2), and water was added to bring the total volume to 100 mL (pH 10). The aqueous solution was stirred (150 rpm) at room temperature for 5 hours, then left to stand for 19 hours as an alkali treatment, and then centrifuged (2600 x g, 4,000 rpm, 1 minute). The resulting precipitate was freeze-dried to obtain 1265.9 mg of powdered shell ginger extract.

[0082] The obtained shell ginger extract contained 939.7 mg of DDK (purity 74.2%) and 190.9 mg of DK (purity 15.1%). Based on the amounts of DDK and DK contained in the crude extract (1 + 2), the recovery rate of DDK in the shell ginger extract was 112%, and the recovery rate of DK was 76%.

[0083] [Example 4. Production of high-purity shell ginger extract using shell ginger leaves] As Example 4, Figure 4 shows a flow diagram outlining the production method for high-purity shell ginger extract using shell ginger leaves as the raw material, carried out on a 100 g scale using a system of 4% (w / v) sodium hydroxide and 1% (w / v) glucose.

[0084] Alpinia ginseng leaves were subjected to thermal drying to obtain dried leaves. 100.0 g of dried leaves were placed in 600 mL of 60% (v / v) aqueous ethanol and subjected to ethanol extraction by leaving the mixture at room temperature for 4 days. The extract was then filtered using a filter (pore size 5 μm) to obtain 282.7 g of filtrate (1) and 357.3 g of residue (1). The entire amount of filtrate (1) was subjected to vacuum concentration to obtain crude extract (1) as the first extract. The crude extract (1) contained 227.5 mg of DDK, but DK was below the lower limit of detection.

[0085] The residue (1) was placed in 600 mL of 60% (v / v) aqueous ethanol and left to stand at room temperature for 3 days for ethanol extraction. This was followed by filtration using a filter (pore size 5 μm) to obtain 448.6 g of filtrate (2). The entire filtrate (2) was concentrated under reduced pressure to obtain crude extract (2) as a second extract. The crude extract (2) contained 150.8 mg of DDK, but the DK content was below the lower limit of detection.

[0086] An aqueous solution containing 4.0 g of sodium hydroxide and 1.0 g of glucose was added to extract (1+2), which was a combination of the total amounts of crude extract (1) and crude extract (2), and water was added to bring the total volume to 100 mL. The resulting aqueous solution (pH 14) was stirred (150 rpm) at room temperature for 5 hours, then left to stand for 19 hours as an alkali treatment, and then centrifuged (2600 x g, 4,000 rpm, 1 minute). The resulting precipitate was freeze-dried to obtain 352.8 mg of a powdered shell ginger extract.

[0087] The obtained shell ginger extract contained 349.3 mg of DDK (purity 99.0%). Based on the amount of DDK contained in the crude extract (1 + 2), the recovery rate of DDK in the shell ginger extract was 82%. [Industrial Applicability]

[0088] The shell ginger extract produced by one embodiment of the method of the present invention contains dihydro-5,6-dehydrokawain and 5,6-dehydrokawain in high purity, and can be used in foods and beverages, cosmetics, pharmaceuticals, quasi-drugs, etc., in anticipation of their pharmacological effects, and is particularly useful in that it can be used as or incorporated into oral agents, topical agents, injections, lotions, etc.

Claims

1. A step of obtaining a crude shell ginger extract by subjecting the dried shell ginger to an extraction treatment using a dehydrokawain-soluble solvent; a step of obtaining a shell ginger extract by subjecting the shell ginger crude extract to a water treatment, an alkali treatment and salting out; A method for producing a shell ginger extract, comprising:

2. The method according to claim 1, wherein the crude extract of shell ginger is obtained by subjecting the extract obtained by the extraction process to solid-liquid separation and / or concentration.

3. The method according to any one of claims 1 to 2, wherein the salting out is performed using at least one sugar selected from the group consisting of glucose, sucrose, and maltose.

4. The method according to any one of claims 1 to 3, wherein the dehydrokawain-soluble solvent is 30% (v / v) to 90% (v / v) aqueous ethanol.

5. The method according to any one of claims 1 to 4, wherein the alkaline treatment is an alkaline treatment using sodium hydroxide at a final concentration of 0.5% (w / v) to 6% (w / v).

6. The method according to any one of claims 1 to 5, wherein the shell ginger extract has a total content of dihydro-5,6-dehydrokawain and 5,6-dehydrokawain of 80% (w / w) or more.

7. The method according to any one of claims 1 to 6, wherein the shell ginger extract has a dihydro-5,6-dehydrokawain content of 70% (w / w) or more and / or a 5,6-dehydrokawain content of 10% (w / w) or more.

8. The method according to any one of claims 1 to 7, wherein the shell ginger extract is a solid shell ginger extract.

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