Method for dissolving poorly water-soluble protein, protein solution obtained thereby, and molded article thereof

Abstract

The present invention provides: a method for dissolving a poorly water-soluble protein; and a method for producing a molded polymer containing a poorly water-soluble protein. According to the present invention, provided is a method for dissolving a poorly water-soluble protein, the method comprising a step of mixing a poorly water-soluble protein with a water-soluble tertiary amine oxide. In addition, the present invention makes it possible to produce a molded article from the protein solution obtained by such a method.

Description

Technical Field

[0001] The present invention relates to a method for dissolving poorly water-soluble protein and a protein solution obtained thereby, and in particular to a method for dissolving poorly water-soluble protein in water-soluble tertiary amine oxide, a protein solution obtained thereby and a molded body thereof. Background Art

[0002] In recent years, SDGs have attracted much attention, and efforts have been made to achieve a sustainable society by effectively using waste resources and maintaining a rich environment without destroying the earth. As part of this, it is hoped that water-insoluble proteins that are difficult to recycle and discarded can be dissolved and used as protein solutions. Summary of the invention

[0003] Technical problem to be solved by the invention

[0004] The inventors of the present invention have found a method for solubilizing poorly water-soluble proteins, which can be recycled in addition to effectively utilizing discarded resources. In addition, the inventors of the present invention have found a method for solubilizing poorly water-soluble proteins in order to present new functions, rather than reducing the molecular weight by hydrolysis. Therefore, the present invention provides a method for solubilizing poorly water-soluble proteins by using water-soluble tertiary amine oxides.

[0005] (Item 1)

[0006] A method for dissolving poorly water-soluble protein, comprising the step of mixing the poorly water-soluble protein with a water-soluble tertiary amine oxide.

[0007] (Item 2)

[0008] The method according to the above item, wherein the mixing step comprises mixing using high shear force and / or vibration.

[0009] (Item 3)

[0010] The method according to any one of the above items is characterized in that the poorly water-soluble protein is dissolved without being hydrolyzed.

[0011] (Item 4)

[0012] The method according to any one of the above items, wherein the water-soluble tertiary amine oxide comprises N-methylmorpholine N-oxide (nMMO).

[0013] (Item 5)

[0014] The method according to any of the above items, wherein the nMMO is at least about 70 w / w % nMMO.

[0015] (Item 6)

[0016] The method according to any one of the above items, wherein the poorly water-soluble protein comprises eggshell membranes, chicken feathers, wool and scales.

[0017] (Item 7)

[0018] A protein solution is provided, wherein the protein solution is obtained by dissolving a poorly water-soluble protein in a water-soluble tertiary amine oxide.

[0019] (Item 8)

[0020] The protein solution according to any one of the above items is characterized in that the poorly water-soluble protein is dissolved without being hydrolyzed.

[0021] (Item 9)

[0022] The protein solution according to any one of the above items, wherein the water-soluble tertiary amine oxide comprises N-methylmorpholine N-oxide.

[0023] (Item 10)

[0024] The protein solution according to any of the above items, wherein the nMMO is at least about 70 w / w % nMMO.

[0025] (Item 11)

[0026] The protein solution according to any one of the above items, wherein the poorly water-soluble protein comprises eggshell membranes, chicken feathers, wool and scales.

[0027] (Item 12)

[0028] A method for preparing a polymer shaped body containing a poorly water-soluble protein, comprising:

[0029] (a) a step of mixing a poorly water-soluble protein with a water-soluble tertiary amine oxide;

[0030] (b) a step of mixing a hydroxyl-containing polymer with a water-soluble tertiary amine oxide;

[0031] (c) a step of mixing the protein solution obtained in step (a) with the polymer solution obtained in step (b); and

[0032] (d) A step of precipitating a polymer shaped body from the solution obtained in the step (c).

[0033] (Item 13)

[0034] The method according to any one of the above items, wherein the hydroxyl-containing polymer comprises a modified hydroxyl-containing polymer in which a functional group is bonded to the hydroxyl-containing polymer.

[0035] (Item 14)

[0036] The method according to any one of the above items, wherein the hydroxyl-containing polymer comprises a saponified product of cellulose, polyvinyl alcohol and polyvinyl acetate.

[0037] (Item 15)

[0038] The method according to any one of the above items, wherein the water-soluble tertiary amine oxide comprises N-methylmorpholine N-oxide (nMMO).

[0039] (Item 16)

[0040] The method according to any of the above items, wherein the nMMO is at least about 70 w / w % nMMO.

[0041] (Item 17)

[0042] The method according to any one of the above items, wherein the poorly water-soluble protein comprises eggshell membranes, chicken feathers, wool and scales.

[0043] (Item 18)

[0044] A shaped body, characterized in that the shaped body is a polymer shaped body containing a poorly water-soluble protein, and the shaped body is obtained by a method comprising the following steps:

[0045] (a) a step of mixing a poorly water-soluble protein with a water-soluble tertiary amine oxide;

[0046] (b) a step of mixing a hydroxyl-containing polymer with a water-soluble tertiary amine oxide;

[0047] (c) a step of mixing the protein solution obtained in step (a) with the polymer solution obtained in step (b); and

[0048] (d) A step of precipitating a polymer shaped body from the solution obtained in the step (c).

[0049] In the present invention, in addition to the disclosed combinations, further combinations of one or more of the above features can be provided. It should be noted that other embodiments and advantages of the present invention can be recognized by those skilled in the art after reading and understanding the following detailed description as needed.

[0050] It should be noted that those skilled in the art will be able to clearly understand the features and significant functions and effects of the present invention other than those described above by referring to the following embodiments of the present invention and the accompanying drawings.

[0051] Effects of the Invention

[0052] The present invention can produce a protein solution that has excellent resource efficiency for water-insoluble proteins such as eggshell membranes, chicken feathers, wool, and scales that are often discarded, and can easily produce a molded product with new functionality.

[0053] The protein solution and the molded product thereof of the present invention can be provided with new functionality in addition to the original properties, and thus can have functionality such as moisture absorption and release, deodorization, and antibacterial properties.

[0054] Furthermore, the molded product of the present invention has no restrictions on its shape and area, and thus can also eliminate the disadvantages of natural proteins (which are limited to a shape corresponding to the original size of the protein). BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Figure 1 This is a microscopic photograph of the poorly water-soluble protein regenerated using the protein solution produced in Example 3.

[0056] Figure 2 This is a microscopic photograph of a polymer molded body produced using the protein solution produced in Example 7.

[0057] Figure 3 This is a microscopic photograph of a polymer molded body produced using the protein solution produced in Example 8. DETAILED DESCRIPTION

[0058] Below, the best solution is shown and the present invention is described. It should be understood that, throughout the scope of this specification, unless otherwise noted, the expression of the singular form also includes the concept of its plural form. Therefore, it should be understood that, unless otherwise noted, the article in the singular form (for example, "a", "an", "the", etc. in English) also includes the concept of its plural form. In addition, it should be understood that, unless otherwise noted, the terms used in this specification are used with the meanings commonly used in the field. Therefore, unless otherwise defined, all professional terms and scientific and technological terms used in this specification have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs. In the event of inconsistency, this specification (including definitions) takes precedence.

[0059] Definitions and / or basic technical contents of terms particularly used in this specification are described below as appropriate.

[0060] In this specification, "about" means ±10% of the subsequent numerical value.

[0061] In this specification, "poorly water-soluble protein" refers to a protein that is transparent and insoluble even when a 0.1% aqueous solution is heated at 80°C for 3 hours. As a method for determining whether it is a poorly water-soluble protein, it can be confirmed by a common method whether the above conditions are met. Examples of poorly water-soluble proteins include eggshell membranes, chicken feathers, wool, and scales.

[0062] In the present specification, the "protein solution" obtained by dissolving a poorly water-soluble protein is interpreted in a broad sense and means a solution in which the poorly water-soluble protein is mainly dissolved.

[0063] In this specification, "water-soluble tertiary amine oxide" is broadly interpreted as water-soluble amine oxide or amine-N-oxide. It refers to the oxide of a nitrogen-containing heterocyclic compound such as a tertiary amine or pyridine. As a water-soluble tertiary amine oxide, for example, N-methylmorpholine N-oxide (nMMO) can be cited. nMMO is a kind of organic compound and is used as an oxidant in organic synthesis. nMMO is an amine oxide of N-methylmorpholine (NMM) with a methyl group substituted on the nitrogen of morpholine.

[0064] In this specification, the "polymer molded product" is interpreted broadly as a molded product containing a polymer as a main component.

[0065] In this specification, "hydroxyl-containing polymer" is broadly interpreted as a polymer compound having a hydroxyl group. Examples of hydroxyl-containing polymers include polysaccharides such as starch, glycogen, cellulose, chitin, agarose, hyaluronic acid, chondroitin sulfate, pectin, and carrageenan, and synthetic polymers such as polyvinyl alcohol (PVA), phenolic resin, and polyvinyl acetate. In addition, examples of hydroxyl-containing polymers include partially saponified products of regenerated cellulose or polyvinyl acetate.

[0066] In this specification, the mixing using "high shear force" means mixing liquids or liquids and solids while shearing with high-speed rotating stirring blades. As a mixer that can obtain high shear force, high-speed shear mixers such as homogenizers, turbine mixers, and biomixers, high-pressure homogenizers, ultrasonic homogenizers, or in-tube mixers (including static mixers and injection molding mixers (single screw, twin screw)) can be cited.

[0067] In this specification, mixing by "vibration" is broadly interpreted as stirring the liquid or solid and the solvent while vibrating them in a container containing the liquid or solid to be mixed. Mixing by vibration can be achieved, for example, by stirring with a stirrer, stirring with ultrasonic vibration, stirring with vibration at the molecular level, and the like.

[0068] In the present specification, the state of "dissolving" includes a state in which the appearance of the solution is transparent, translucent or emulsified.

[0069] (Preferred embodiment)

[0070] The preferred embodiments of the present invention are described below. The embodiments provided below are provided for a better understanding of the present invention, and the scope of the present invention is not limited to the following description. Therefore, it goes without saying that those skilled in the art can appropriately change within the scope of the present invention with reference to the description in this specification. In addition, the following embodiments of the present invention can be used alone or in combination.

[0071] In one aspect of the present invention, a method for solubilizing a poorly water-soluble protein is provided, the method comprising the step of mixing the poorly water-soluble protein with a water-soluble tertiary amine oxide.

[0072] [Poorly soluble protein]

[0073] In one embodiment, the method of the present invention can solubilize a poorly water-soluble protein by mixing the poorly water-soluble protein with a water-soluble tertiary amine oxide.

[0074] In one embodiment, the poorly water-soluble protein refers to a protein that remains transparent and insoluble even when a 0.1% aqueous solution thereof is heated at 80° C. for 3 hours. Examples of the poorly water-soluble protein include eggshell membranes, chicken feathers, wool, and scales.

[0075] In one embodiment, eggshell membranes can be used as water-insoluble proteins. The source of the eggshell membranes as water-insoluble proteins dissolved by the method of the present invention is not particularly limited. For example, as eggshell membranes, eggshell membranes of poultry birds can be used, such as chickens, quails, turkeys, ducks, domestic ducks, geese, ostriches, helmeted guinea fowl (Numida meleagris), long-tailed chickens, bantams, pigeons, mute swans, emus or pheasants. In one embodiment of the present invention, chickens are preferred from the perspective of being easy to obtain, laying eggs, laying eggs in large quantities, and having established mass breeding methods.

[0076] Usually, eggshells are attached to eggshell membranes, and when directly hydrolyzed, the eggshells remain in an insoluble state and are present as foreign matter when a molded body is obtained, which is not preferred. In order to remove the eggshells, it is preferred to immerse the eggshell membranes containing the eggshells in an aqueous solution of hydrochloric acid, phosphoric acid, etc., dissolve the eggshells in water, filter, and remove them in advance by washing with water.

[0077] [Crushing of poorly water-soluble proteins]

[0078] In one embodiment, in order to facilitate the dissolution of the poorly water-soluble protein, the poorly water-soluble protein can be crushed. In one embodiment, the diameter size in the case of crushing the poorly water-soluble protein is not particularly limited. For example, the poorly water-soluble protein can have a diameter of about 0.1 μm or more, about 0.2 μm or more, about 0.3 μm or more, about 0.4 μm or more, about 0.5 μm or more, about 0.6 μm or more, about 0.7 μm or more, about 0.8 μm or more, about 0.9 μm or more, about 1.0 μm or more, about 1.5 μm or more, about 2.0 μm or more, about 3.0 μm or more, about 4.0 μm or more, or about 5.0 μm or more. In addition, the diameter can be about 5 mm or less, about 4 mm or less, about 3 mm or less, about 2 mm or less, or about 1 mm or less. In one embodiment, in the case of crushing, the diameter of the poorly water-soluble protein is preferably about 0.1 μm or more and about 5 mm or less, and more preferably about 1 μm or more and about 1 mm or less. When the amount falls within this range, when a poorly water-soluble protein is prepared as a solution using the method of the present invention, the protein can be uniformly dissolved.

[0079] [Dissolution of poorly water-soluble proteins]

[0080] In one embodiment, the method of the present invention can dissolve the poorly water-soluble protein by mixing the poorly water-soluble protein with a water-soluble tertiary amine oxide, for example, by applying high shear force and / or vibration to the mixed solution of the poorly water-soluble protein and the water-soluble tertiary amine oxide.

[0081] In one embodiment, as a solvent for dissolving poorly water-soluble proteins, water-soluble tertiary amine oxides can be cited, and as water-soluble tertiary amine oxides, for example, N-methylmorpholine N-oxide (nMMO) can be used. From the viewpoint of the solubility of poorly water-soluble proteins, nMMO is preferred, and from the perspective of regenerating a molded body from a solubilized poorly water-soluble protein as described below, nMMO is reused, which is also preferred from this aspect. In one embodiment, when a poorly water-soluble protein is dissolved in N-methylmorpholine N-oxide (nMMO), as an nMMO solution, a solution of at least about 70w / w%, at least about 75w / w%, at least about 80w / w%, at least about 85w / w%, at least about 90w / w%, at least about 95w / w%, at least about 97w / w%, at least about 98w%, at least about 99w / w% can be used. In one embodiment, it is preferred to use an nMMO solution of about 80w / w% or more.

[0082] nMMO is a kind of organic compound, and is a colorless solid used as an oxidant in organic synthesis. It is equivalent to an amine oxide of N-methylmorpholine (NMM) with a methyl group substituted on the nitrogen of morpholine. It can also be used as a sacrificial reagent in catalytic oxidation reactions based on osmium tetroxide, or Sharpless oxidation, TPAP oxidation, etc. nMMO acts as a reoxidant, which reoxidizes the catalyst in a state where the substrate is oxidized and the activity is reduced, and activates it again. nMMO is usually commercially available as a 50% aqueous solution. Anhydrous nMMO can also be obtained, but the aqueous solution can also be dehydrated and dried before use. Since the aqueous solution dissolves cellulose, it can also be used as a solvent for the manufacture of Lyocell.

[0083] In one embodiment, the concentration of the poorly water-soluble protein in the case of dissolving the poorly water-soluble protein is not particularly limited, and is preferably about 0.1% to about 20%, for example, about 0.1%, about 0.2%, about 0.5%, about 0.8%, about 1.0%, about 1.5%, about 2.0%, about 2.5%, about 3.0%, about 3.5%, about 4.0%, about 4.5%, about 5.0%, about 6.0%, about 7.0%, about 8.0%, about 9.0%, about 10%, about 11%, about 12%, about 13%, about 14%, about 15%, about 16%, about 17%, about 18%, about 19% or about 20%.

[0084] In one embodiment, the temperature of the solution in the case of dissolving the poorly water-soluble protein is not particularly limited, but is preferably above about 40°C, more preferably above about 45°C, above 50°C, above about 55°C, above 65°C, above about 70°C, above 75°C, above about 80°C, or above about 90°C.

[0085] In one embodiment, when dissolving a poorly water-soluble protein, a solution mixed with the poorly water-soluble protein and the water-soluble tertiary amine oxide can be stirred according to a conventional method, for example, a known stirrer can be used for stirring. In one embodiment, a solution mixed with the poorly water-soluble protein and the water-soluble tertiary amine oxide can also be stirred using a high-viscosity stirrer or a homogenizer or other stirrer with high shear force, or an ultrasonic stirrer or the like can also be used.

[0086] In one embodiment, in the method of the present invention, the poorly water-soluble protein can be dissolved without being hydrolyzed. In this case, it is preferred that the poorly water-soluble protein is pulverized into the above-mentioned diameter and then mixed with the water-soluble tertiary amine oxide for dissolution.

[0087] In the prior art, in order to make a water-insoluble protein into a solution, it is dissolved by hydrolysis. The hydrolysis of the protein is carried out by acid (hydrochloric acid, sulfuric acid, etc.), alkali (sodium hydroxide, potassium hydroxide, etc.) or proteolytic enzyme (enzyme of microbial origin, enzyme of plant origin, enzyme of animal origin), for example, when hydrolyzed at high temperature in the presence of alkali, a solubilized protein with a relatively large molecular weight is proposed (for example, refer to Japanese Patent 6288686). In addition, by making the proteolytic enzyme with an optimum pH value in the alkaline region play a role, a protein hydrolyzate with a high cystine content is proposed (for example, refer to Japanese Patent Publication No. 2018-177713).

[0088] In addition, a technology has been proposed for dissolving protein in thiopropionic acid or the like and spinning a fiber aggregate by an electrospinning method (for example, refer to Japanese Patent Gazette No. 2009-89859 and Japanese Patent 5166953). In addition, a method has been proposed for processing a soluble protein obtained by hydrolyzing the protein in the presence of a reducing agent into a fiber blank (for example, refer to Patent 4387806 and Japanese Patent Gazette No. 2004-84154).

[0089] However, in the hydrolysis under the presence of alkali recorded in Japanese Patent 6288686, in order to stop the decomposition reaction, a step of neutralization with an acidic substance is required, and there is a problem of reduced cystine content contained in the protein in the neutralization step. In addition, in the hydrolysis using enzymes recorded in Japanese Patent Publication No. 2018-177713, it is difficult to obtain solubles of proteins with large molecular weight, and the protease itself as a catalyst is expensive, so the manufacturing cost becomes high.

[0090] In addition, the method of hydrolysis using an acid has the following problems: the apparatus is easily corroded, and the protein is excessively decomposed, deviating from the target molecular weight distribution and becoming too low in molecular weight, coloring to brown, and by-products other than the target hydrolyzate are easily generated.

[0091] Furthermore, in the fiber manufacturing method described in Japanese Patent Laid-Open No. 2009-89859 and Japanese Patent No. 5166953, after protein is dissolved in acid, spinning is performed using a special device, and a natural protein structure is not formed in the fiber assembly. In addition, in the film or sheet described in Japanese Patent No. 4387806 and Japanese Patent Laid-Open No. 2004-84154, based on the use of hydrolyzed solubilized protein, the use is limited to wound covering materials such as bandages.

[0092] In addition, Japanese Patent No. 4070579 proposes a method for utilizing poorly water-soluble proteins to introduce functional components into viscose rayon by dissolving poorly water-soluble proteins such as animal hair at pH 8 to 12, mixing the cross-linked proteins with viscose in an alkaline aqueous solution and spinning the cross-linked proteins. However, in this method, the protein is cross-linked with a cross-linking agent in advance after alkaline hydrolysis, and becomes different from the original protein, which is the same as other prior arts.

[0093] In addition, Japanese Patent No. 5071613 proposes dissolving a poorly water-soluble active ingredient (such as titanium dioxide or zinc oxide) in an aqueous solution containing electrolytes by using an amphoteric polymer compound having an anionic dissociation group and a cationic dissociation group in one molecule, or by using a combination of an anionic polymer compound and a cationic polymer compound, in order to attach a poorly water-soluble active ingredient to the target surface of the tooth. However, poorly water-soluble proteins are not dissolved in this technology.

[0094] Therefore, in one embodiment of the present invention, in the method of the present invention, the water-insoluble protein can be dissolved without hydrolysis, so that the original structure and characteristics of the natural protein can be possessed. In addition, by not hydrolyzing the water-insoluble protein, it can be formed into fibers or the like in a high molecular weight state, so that the strength of the molded body can be enhanced, and the protein content can also be increased. Furthermore, for example, when eggshell membranes are used as water-insoluble proteins, since the fibrous form remains as it is, structural characteristics such as increased moisture retention, deodorization, and cell proliferation can also be expected.

[0095] [Protein solution of poorly water-soluble protein]

[0096] In one aspect of the present invention, a protein solution is provided by dissolving a poorly water-soluble protein in a water-soluble tertiary amine oxide. The protein solution of the present invention is a solution obtained by dissolving a poorly water-soluble protein. Since the poorly water-soluble protein is originally poorly soluble in water, it is impossible or impractical to measure the molecular weight when it is insoluble in water even by gel permeation chromatography. In addition, it is also difficult to decompose the protein solution (obtained by dissolving the poorly water-soluble protein in a water-soluble tertiary amine oxide) and determine its amino acid sequence.

[0097] In one embodiment of the present invention, the protein solution of the poorly water-soluble protein of the present invention can be formed into a protein solution obtained without causing the poorly water-soluble protein to produce a protein derivative such as hydrolysis. In one embodiment, the protein solution of the poorly water-soluble protein of the present invention can be obtained by dissolving the poorly water-soluble protein in an aqueous solution of a water-soluble tertiary amine oxide and gelling it.

[0098] As the water-soluble tertiary amine oxide or its concentration, or the poorly water-soluble protein, those described elsewhere in the present specification can be used.

[0099] [Regeneration of solubilized poorly water-soluble proteins]

[0100] In one aspect of the present invention, there is provided a method for preparing a polymer molding containing a water-insoluble protein, the method comprising: (a) a step of mixing the water-insoluble protein with a water-soluble tertiary amine oxide; (b) a step of mixing a hydroxyl-containing polymer with a water-soluble tertiary amine oxide; (c) a step of mixing the protein solution obtained in step (a) with the polymer solution obtained in step (b); and (d) a step of precipitating the polymer molding using the solution obtained in step (c).

[0101] In one embodiment of the present invention, the water-insoluble protein can be precipitated and regenerated by extruding the solubilized water-insoluble protein into water or an aqueous solution of a water-soluble tertiary amine oxide of less than about 60w / w%. For example, in an aqueous solution of nMMO less than about 60w / w%, the water-insoluble protein dissolved in nMMO is extruded to form short fibers (cotton), or the water-insoluble protein dissolved in nMMO is coated into a film with a glass plate or the like, and immersed in an aqueous solution of nMMO less than about 60w / w%, so that it is precipitated in a film, thereby regenerating the water-insoluble protein. In one embodiment, the regenerated shape can be cotton-like or film-like, and after regeneration, it can be further washed and dried to form a final product.

[0102] Therefore, in one aspect of the present invention, there is provided a polymer shaped body containing a poorly water-soluble protein, wherein the shaped body is obtained by a method comprising the following steps:

[0103] (a) a step of mixing a poorly water-soluble protein with a water-soluble tertiary amine oxide; (b) a step of mixing a hydroxyl-containing polymer with a water-soluble tertiary amine oxide; (c) a step of mixing the protein solution obtained in step (a) with the polymer solution obtained in step (b); and (d) a step of precipitating a polymer molded body using the solution obtained in step (c). As described above, the protein solution of the present invention is a solution obtained by dissolving a poorly water-soluble protein. Since the poorly water-soluble protein is originally difficult to dissolve in water, it is impossible or impractical to measure the molecular weight without dissolving in water even using gel permeation chromatography. In addition, it is also difficult to decompose the protein solution (obtained by dissolving the poorly water-soluble protein in a water-soluble tertiary amine oxide) and determine its amino acid sequence. Therefore, it is also difficult to present the polymer molded body obtained from the above-mentioned protein solution of the present invention based on structure and characteristics.

[0104] In one embodiment, the polymer molded product is not particularly limited as long as it is a molded product obtained from the hydroxyl-containing polymer serving as a material for the method of the present invention, and examples thereof include fibers, nonwoven fabrics, and films.

[0105] Examples of the properties of the molded article obtained by the method of the present invention include moisture absorption and release properties, deodorization properties, antibacterial properties, skin protection properties, cell proliferation properties, biocompatibility, and metal adsorption properties.

[0106] In one embodiment, in the method for producing the polymer shaped article of the present invention, in order to mix the poorly water-soluble protein and the hydroxyl-containing polymer, it is preferred that the poorly water-soluble protein and the hydroxyl-containing polymer are separately mixed and dissolved in a water-soluble tertiary amine oxide in advance.

[0107] In one embodiment, in the method for preparing the polymer molding of the present invention, the water-soluble tertiary amine oxide that becomes the solvent of the water-insoluble protein and the water-soluble tertiary amine oxide that becomes the solvent of the hydroxyl-containing polymer may be the same or different. In addition, in one embodiment, as the water-soluble tertiary amine oxide, for example, N-methylmorpholine N-oxide (nMMO) can be used. In order to reuse the water-soluble tertiary amine oxide, it is preferred that the solvent for dissolving the water-insoluble protein and the hydroxyl-containing polymer is the same.

[0108] In one embodiment, the aqueous solution of the water-soluble tertiary amine oxide used for the precipitation of the poorly water-soluble protein can be concentrated and reused in the method of the present invention.

[0109] In one embodiment, as the hydroxyl-containing polymer, a modified hydroxyl-containing polymer having a functional group bonded thereto can also be used. By mixing an nMMO solution of a poorly water-soluble protein and an nMMO solution of a modified hydroxyl-containing polymer, and extruding the mixture into water or an aqueous solution of a water-soluble tertiary amine oxide at a concentration of less than about 60 w / w%, a functional polymer molded body can be obtained.

[0110] In one embodiment, as the hydroxyl-containing polymer or modified hydroxyl-containing polymer, cellulose, regenerated cellulose, polyvinyl alcohol and saponified polyvinyl acetate can be used, preferably regenerated cellulose. In addition, the saponified polyvinyl acetate can be any one in which a part of polyvinyl acetate is saponified to contain hydroxyl groups (OH).

[0111] In one embodiment, the protein solution of the poorly water-soluble protein dissolved by the method of the present invention and its molded body have the functions and characteristics of the poorly water-soluble protein itself as a material, for example, in addition to moisturizing, metal ion adsorption, deodorization, antibacterial effects, etc., it can also have physiological activities such as fibroblast proliferation, active enzyme removal, cell activation, etc. In one embodiment, a polymer material can also be selected to facilitate the function and characteristics of the poorly water-soluble protein.

[0112] In one embodiment of the present invention, the protein solution and polymer molded product of the present invention are obtained from a poorly water-soluble protein such as eggshell membrane derived from a natural component, and therefore have excellent adhesion to human skin tissue.

[0113] In one embodiment of the present invention, the protein solution and polymer molded product of the present invention contain a poorly water-soluble protein component such as eggshell membranes and can have substantially the same properties as natural poorly water-soluble proteins such as eggshell membranes.

[0114] In this specification, "or" is used when "at least one or more" of the items listed in the article can be used. The same applies to "or". In this specification, when it is clearly stated that "two values" are "within a range", the range also includes the two values ​​themselves.

[0115] All references such as scientific literature, patents, and patent applications cited in this specification are incorporated herein by reference to the same extent as if each was specifically described.

[0116] In order to facilitate understanding, the preferred embodiments are shown above to illustrate the present invention. Below, the present invention is described based on examples, but the above description and the following examples are provided only for illustration and are not intended to limit the present invention. Therefore, the scope of the present invention is not limited to the embodiments and examples specifically described in this specification, but is only limited by the claims.

[0117] [Example]

[0118] (Test Example 1: Dissolution of poorly water-soluble protein)

[0119] According to Table 1 below, wool, pulverized eggshell membranes, unpulverized eggshell membranes, scales or chicken feathers were dissolved in 60 w / w%, 70 w / w%, 85 w / w% of N-methylmorpholine N-oxide (nMMO) or water. The protein concentration, stirring time, stirring and shaking time, and homogenization time are shown in Table 1, respectively.

[0120] [Table 1]

[0121]

[0122] For dissolution of wool, pulverized eggshell membranes, unpulverized eggshell membranes, scales or chicken feathers, these were mixed with nMMO (60 w / w%, 70 w / w%, or 85 w / w%) or water, respectively, and stirred under the conditions of Table 1. In addition, the eggshell membranes were pulverized into several tens to several hundreds of microns using a common pulverizer such as a pulse pulverizer or a hammer mill. In addition, the pulverization is preferably performed after washing and drying the eggshell membranes.

[0123] As shown in Table 1, Examples 1 to 10 all showed transparent or semi-transparent gels, and it was confirmed that the poorly water-soluble protein in each Example was dissolved. On the other hand, Comparative Examples 1 to 4 all showed no dissolution.

[0124] Next, eggshell membranes were dissolved using a solvent other than nMMO. The pulverized eggshell membranes were prepared, mixed with each solvent, and dissolved by stirring at 80°C for 1 hour.

[0125] The solvents used and the results are shown in Table 2.

[0126] [Table 2]

[0127]

[0128] As shown in Table 2, it was found that eggshell membranes were insoluble in most solvents but dissolved when hydrolyzed with an acid or an alkali. In addition, eggshell membranes also dissolved when 85 w / w% of nMMO was used.

[0129] (Test Example 2: Regeneration of poorly water-soluble protein from a poorly water-soluble protein solution and preparation of a polymer molded body)

[0130] Using the protein solutions of Examples 3, 7 and 8 described in Table 1, water-poorly soluble proteins were regenerated or polymer molded bodies were prepared. After the eggshell membrane powder was dissolved in the nMMO solution as shown in Examples 3, 7 or 8, 4 g of the solution was taken on a glass plate and spread into a circular film with a diameter of about 5 cm. It was insoluble in water (filmed), washed with water and dried under reduced pressure at room temperature. For the protein solution of Example 3, water-poorly soluble proteins were directly regenerated, and for the protein solutions of Examples 7 and 8, regenerated cellulose fibers (rayon) were mixed and filmed. Figure 1 This is a microscopic photograph of a thin film when the protein solution of Example 3 is used. Figure 2 This is a microscopic photograph of a thin film when the protein solution of Example 7 is used. Figure 3 This is a microscopic photograph of a thin film when the protein solution of Example 8 was used.

[0131] (Notes)

[0132] As described above, the present invention has been described using the preferred embodiments of the present invention, but it should be understood that the scope of the present invention should be interpreted only by the claims. Patents, patent applications and other documents cited in this specification should be understood as being cited as references to this specification as their contents themselves are specifically recorded in this specification. This application claims priority based on Japanese Patent Application No. 2022-76053 filed with the Japan Patent Office on May 2, 2022, and its entirety is cited as a reference in the same manner as the contents constituting this application.

[0133] Industrial Applicability

[0134] The protein solution and its molded product obtained by the method of the present invention can be used for chemical applications in the form of fibers and films, facial mask materials or powdered cosmetic applications, medical applications as wound dressing materials, and the field of regenerative medicine as cell culture scaffold materials. In addition, due to good biodegradability, it can also be expected to be used as agricultural raw materials.

Claims

1. A method for solubilizing a poorly water-soluble protein, wherein: The method comprises the steps of mixing a poorly water-soluble protein with a water-soluble tertiary amine oxide.

2. The method according to claim 1, wherein: The step of mixing includes mixing using high shear forces and / or vibration.

3. The method according to claim 1 or 2, characterized in that: The poorly water-soluble protein is dissolved without being hydrolyzed.

4. The method according to any one of claims 1 to 3, wherein: The water-soluble tertiary amine oxide comprises N-methylmorpholine N-oxide (nMMO).

5. The method according to claim 4, wherein: The nMMO is at least about 70 w / w % nMMO.

6. The method according to any one of claims 1 to 5, wherein: The poorly water-soluble proteins include eggshell membranes, chicken feathers, wool and scales.

7. A protein solution obtained by dissolving a poorly water-soluble protein in a water-soluble tertiary amine oxide.

8. The protein solution according to claim 7, characterized in that The poorly water-soluble protein is dissolved without being hydrolyzed.

9. The protein solution according to claim 7 or 8, wherein The water-soluble tertiary amine oxide comprises N-methylmorpholine N-oxide.

10. The protein solution according to claim 9, wherein The nMMO is at least about 70 w / w % nMMO.

11. The protein solution according to any one of claims 7 to 10, wherein The poorly water-soluble proteins include eggshell membranes, chicken feathers, wool and scales.

12. A method for producing a polymer molded body containing a poorly water-soluble protein, wherein: include: (a) a step of mixing a poorly water-soluble protein with a water-soluble tertiary amine oxide; (b) a step of mixing a hydroxyl-containing polymer with a water-soluble tertiary amine oxide; (c) a step of mixing the protein solution obtained in step (a) with the polymer solution obtained in step (b); and (d) A step of precipitating a polymer shaped body from the solution obtained in the step (c).

13. The method according to claim 12, wherein: The hydroxyl-containing polymer includes a modified hydroxyl-containing polymer in which a functional group is bonded.

14. The method according to claim 13, wherein: The hydroxyl-containing polymer comprises a saponified product of cellulose, polyvinyl alcohol and polyvinyl acetate.

15. The method according to any one of claims 12 to 14, wherein: The water-soluble tertiary amine oxide comprises N-methylmorpholine N-oxide (nMMO).

16. The method according to claim 15, wherein: The nMMO is at least about 70 w / w % nMMO.

17. The method according to any one of claims 12 to 16, wherein: The poorly water-soluble proteins include eggshell membranes, chicken feathers, wool and scales.

18. A molded body, characterized in that The molded body is a polymer molded body containing a poorly water-soluble protein, and the molded body is obtained by a method comprising the following steps: (a) a step of mixing a poorly water-soluble protein with a water-soluble tertiary amine oxide; (b) a step of mixing a hydroxyl-containing polymer with a water-soluble tertiary amine oxide; (c) a step of mixing the protein solution obtained in step (a) with the polymer solution obtained in step (b); and (d) A step of precipitating a polymer shaped body from the solution obtained in the step (c).

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