KR100847299B1 - Fraction of silk peptide with an excellent moisturizing effect and use thereof - Google Patents

Abstract

A fraction of silk peptide is provided to improve skin-moisturizing effects by removing fractions having no skin-moisturizing effects from the degraded products of silk protein, inhibit side effects and sticky properties, and maintain a protection film on the skin for a long time. A cosmetic composition for moisturizing the skin comprises a precipitated fraction of silk peptide which is prepared by mixing silk peptide with a mixed solvent of water and 60-78%(v/v) of organic solvent selected from methanol, ethanol and isopropanol, and recovering the precipitated products, and is applied to the skin, scalp or hair.

Description

Silk peptide fraction with excellent moisturizing ability and its use {FRACTION OF SILK PEPTIDE WITH AN EXCELLENT MOISTURIZING EFFECT AND USE THEREOF}

The present invention relates to a fraction having excellent moisturizing ability of the silk peptide, a moisturizing composition containing the fraction as an active ingredient, and a method for preparing the same.

From the medical point of view, the skin functions as a protective film at the outermost part of the human body and prevents the loss of biological components such as water and electrolytes, and also plays an important role in blocking the influx of external harmful substances. . In particular, the stratum corneum forms the outermost layer of the skin and plays an important role in preventing the loss of moisture inside the skin from the dry external environment. At the same time, the stratum corneum possesses adequate moisture to show flexibility and elasticity.

Looking at the skin that constitutes the outermost part of the body, the stratum corneum of normal skin usually contains more than 10% water, which is elastic and flexible. The content of water decreases gradually from the deep dermis to the epidermis of the surface when viewed on the skin. The stratum corneum consists of approximately 15% water, 70% protein and 15% lipids, whereas the dermal layer, especially keratinocytes, consists of 70% water, 15% protein and 5% lipid. As the keratinocytes get closer to the surface, the water content gradually decreases, eventually reaching 5-10%. No matter how good skin is, the outermost skin does not contain more than 20% water. The stratum corneum's moisture content, commonly referred to as moist skin, is around 15%.

However, the skin moisture balance is lost due to various factors such as aging, changes in hormone secretion, external environment such as wind, temperature and sunlight, and physical factors such as face washing and shaving, and it is easy to become dry skin with moisture content of 10% or less in the stratum corneum. . Due to this, the elasticity and flexibility of the skin is lost, and ultimately the protective function of the skin is lost, causing cracking, erythema, itching, and the like, and worsening, skin diseases such as psoriasis and atopy occur.

In order to solve such a problem, it may be the most ideal way to solve the causative factors, but since the causes are various and the majority of the force majeure causes, the next best measures are taken. The method may be a method of preventing the evaporation of moisture of the skin cells themselves to prevent the decrease of the skin moisture content and a method of minimizing irritation from the external environment by forming an artificial moisturizing film on the skin. Among them, a method of forming an artificial moisturizing film is the simplest, and various types of skin moisturizers and moisturizing cosmetics have been developed for this purpose.

However, skin-friendly materials are being spotlighted as conventional moisturizers and moisturizing cosmetic raw materials, but there is no problem. For example, water-soluble polyhydric alcohols such as glycerin and sorbitol, which are the most used moisturizers, have excellent moisturizing power, but are very sticky, causing discomfort and are easily separated from the skin surface due to their physical effects. Is hard to expect. In addition, raw materials such as propylene glycol and 1,3-butylene glycol may cause skin side effects such as erythema when used in large quantities or in multiple doses. In addition, the natural moisturizing factor (NMF), sodium lactate (Na-lactate), sodium pyrrolidone carboxylic acid sodium (PCA-Na), and urea (Urea) are highly electrolytic and emulsify stability in cosmetics and moisturizer products. There is a problem that harms the effect is also limited.

Recently, efforts are being made to form a moisturizing film on the skin by using bio-derived or biological agents instead of chemical agents. Among them, there are many efforts to utilize natural extracts, various proteins, and degradation products thereof as moisturizing ingredients, and in fact, products containing these ingredients have been developed and sold. Among them, silk-related products are emerging as the best material in terms of production cost, skin affinity, and applicability of raw materials.

Silk is a protein-based fiber composed of fibroin and sericin, which was previously used mainly for cloth, but recently, research has shown that silk protein and its degradation products, peptides and amino acids, lower blood cholesterol levels, It has been found that there is a hangover and dementia prevention effect, which has attracted much attention as a health functional food and cosmetics. Among such effects, silk-derived proteins and their degradation products, silk peptides, have moisturizing effects and have been disclosed in various patents and papers. Among them, Korean Patent No. 10-0428431 discloses the use of a degradation product (low molecular fibroin protein) by proteolytic enzymes of fibroin protein, and Korean Patent No. 10-0652122 discloses the use of the hydrolysis product of sericin. Korean Patent No. 10-2003-0053873, Korean Patent No. 10-2003-0018086 disclose the use of sericin protein, and in Journal of Cosmetic Dermatology, 2005, 4: 250-257, The possibility of use as a moisturizer is mentioned.

However, most of the literature mentions sericin and its degradation products in silk proteins, and the results are mostly for a short time-limited moisturizing effect, making it difficult to obtain sufficient moisturizing effects in actual consumer use. It is true.

In order to solve the above problems, the present inventors select only the fractions having excellent functional moisturizing effect from the conventionally used silk protein degradation products, in particular, the degradation products of fibroin protein. By removing the specific silk peptide fraction having an excellent moisturizing effect was completed the present invention.

The present invention relates to a moisturizing composition containing the excellent moisturizing ability of the silk peptide as an active ingredient and a method for producing the same.

More specifically, the present invention provides a cosmetic composition containing an excellent moisturizing fraction of the silk peptide as an active ingredient. In another aspect, the present invention provides a composition for preventing and / or treating skin dryness, which contains a fraction having excellent moisturizing ability of silk peptide as an active ingredient.

 In another aspect, the present invention provides a method for selecting a moisturizing fraction from silk peptides. The screening method may include the step of adding and mixing a mixed solvent of water and an organic solvent to the silk peptide, followed by precipitation, and obtaining a precipitate fraction obtained by the precipitation.

In another aspect, the present invention provides a method for producing a skin moisturizing composition comprising the step of selecting a fraction having excellent moisturizing ability from the silk peptide.

The skin moisturizing composition according to the present invention has no skin side effects and stickiness, and forms a moisturizing film on the surface of the skin for a long time to exert an excellent moisturizing effect and imparts additional effects such as improving skin roughness and preventing skin aging by skin moisturizing. Done.

Hereinafter, the present invention will be described in more detail.

In the present invention, the silk peptide is obtained from the silk protein, silk means the silk made by the silk insects, and preferably means gajamsa that silkworms die. Silk protein refers to a high molecular weight protein composed of fibroin and sericin obtained by treating such silk or silkworm cocoons with various refining methods. Silk peptides usable in the present invention are all obtained by decomposing such a silk protein, especially silk fibroin protein to low molecular weight material by decomposition methods such as acid-base hydrolysis, protease digestion, high pressure-high temperature hydrolysis, etc. Decomposition products. The decomposition method of the silk protein is a method commonly known in the art, anyone skilled in the art can easily obtain the silk peptide from the silk protein by performing the decomposition method.

These silk peptides are mixed with various amino acids and peptides. Silk peptides are known to contain 18 natural amino acids, including 8 essential amino acids and 10 non-essential amino acids. Silk peptide used in the present invention can be effective even if it is not absorbed into the skin or body at least to form a moisturizing film on the surface of the skin, the molecular weight range is not limited, usually the weight average molecular weight 75 to 10,000, preferably 75 It can use the thing of the range of 1000.

As described above, silk peptides contain various amino acids and various peptides to which they are bound, and thus have the advantage of being able to exert various and synergistic effects. May contain ingredients that work or cause adverse effects. With this in mind, in the present invention, as a result of measuring the moisturizing effect on the various fractions of the silk peptide, it was found that the specific moisturizing effect difference between the fractions and the residues is remarkable or the residue does not show any moisturizing effect at all. Therefore, the silk peptide of the present invention has the advantage that it can be used in the form of specific fractions that do not exhibit a moisturizing effect or exclude components that do not themselves degrade from silk protein, thereby achieving a high moisturizing effect.

In order to obtain the silk peptide fraction described above, various extraction or fractionation methods and conditions may be used, and any methods and conditions conventionally used in the related art may be used within the scope that does not adversely affect the structure and activity of the silk peptide. Can be. Examples include water-organic solvent extraction, supercritical fluid extraction, acid-base extraction, and the like.

In a preferred embodiment of the present invention, the silk peptide fraction may be a fraction obtained by a water-organic solvent extraction method using a mixture of water and an organic solvent in a specific ratio as an extraction solvent. At this time, the organic solvent that can be used may be any one commonly used in the art, for example, straight or branched alcohol having 1 to 10 carbon atoms, such as methanol, ethanol, propanol, isopropanol, butanol, isobutanol, At least one selected from the group consisting of acetone, acetonitrile, chloroform and the like may be used, and more preferably, at least one selected from the group consisting of methanol, ethanol, isopropanol, acetone and the like may be used. Preferably, the silk peptide fraction is a precipitate fraction obtained by mixing with water and the organic solvent as described above.

When water-organic solvent extraction, the use amount of the organic solvent as the extraction solvent increases the disadvantages of separation as well as fractions less functional, there is a disadvantage that the extraction efficiency decreases when the use amount of the organic solvent is less. Therefore, in consideration of this point, the concentration of the organic solvent in the water used for the silk peptide fraction in the present invention is 50 to 95% (v / v), preferably 50 to 78% (v / v). Preferably it is 60 to 78% (v / v), most preferably 62 to 78% (v / v). In addition, the organic solvent type is advantageous to obtain only the fraction showing that the methanol and / or ethanol shows the optimal moisturizing ability.

The silk peptide fraction used in the present invention means the supernatant fraction and the precipitate fraction obtained by extracting the silk peptide from the water-organic solvent, and in order to exert the best moisturizing ability, 50 to 95% (v / v), preferably Is a precipitate obtained when extracted with an aqueous solution of methanol and / or ethanol at a concentration of preferably from 60 to 78% (v / v), more preferably from 62 to 78% (v / v), from 50 to 78% (v / v). It is better to use fractions. Among these, the silk peptide precipitate fraction obtained using 62 to 78% (v / v), especially about 70% (v / v) aqueous ethanol solution showed very good water retention, while the same obtained supernatant fraction was buffered. It is shown that the water retention capacity is lower than that of the solution, and when the precipitate fraction obtained by using the ethanol aqueous solution of the above concentration as a solvent is used as the active ingredient of the moisturizing action, the moisturizing effect is excluded or the moisturizing action is excluded. This excellent component can obtain the concentrated effect, and can exhibit a remarkably elevated moisturizing effect.

The content of the silk peptide fraction contained in the moisturizing composition of the present invention can be appropriately adjusted according to the use, application form, purpose of use and the desired effect of the composition, in consideration of the content-to-content effect, for example, 0.0001 with respect to the total composition weight To 99% by weight, preferably 0.001 to 50% by weight, more preferably 0.01 to 10% by weight, most preferably 0.1 to 5% by weight. When the content in the composition of the effective content is less than the above range can not obtain a substantial moisturizing effect, if the above range is less effective than the content compared to the content is not economical, it is good in the above range.

The moisturizing composition containing the excellent moisturizing fraction of the silk peptide of the present invention as an active ingredient is a concept including both the cosmetic composition and the pharmaceutical composition, depending on the use and the desired effect, and depending on the route of administration, oral, transdermal , Subcutaneous, or intravenous administration, preferably oral or transdermal, more preferably transdermal, may be a composition.

The cosmetic composition is applied to the skin, scalp or hair percutaneously, means a composition that can be used in the manufacture of all cosmetic products, such as basic cosmetics, makeup cosmetics, body products, shaving products, hair products, warning agent, spray It may be formulated in the form of a preparation, a suspension, an emulsion, a cream, a gel, a foam, and the like, but the form is not particularly limited. In addition, the pharmaceutical composition exhibits the effect of preventing and / or treating a disease caused by skin and / or hair dryness due to moisturizing action, and is mainly used orally or percutaneously, and includes warnings, sprays, suspensions, It may be formulated in the form of emulsion, cream, gel and the like, but there is no particular limitation on the form. Diseases caused by the dryness include skin cracking, erythema, itching, psoriasis, atopy and the like. Therefore, the pharmaceutical composition of the present invention may be a composition for preventing and / or treating a disease caused by at least one dryness selected from the group consisting of skin cracking, erythema, itching, psoriasis and atopic dermatitis.

The cosmetic composition and the pharmaceutical composition excellent in moisturizing power according to the present invention can also exhibit effects such as skin aging prevention, wrinkle improvement, skin roughness improvement, etc. by the excellent moisturizing power, and thus have an excellent skin condition improvement and skin condition deterioration suppression effect. .

The cosmetic composition and the pharmaceutical composition of the present invention, in addition to the active ingredient, all kinds of ingredients usable for commercialization or formulation, such as perfumes, pigments, fungicides, antioxidants, preservatives, humectants, thickeners, excipients, diluents, inorganic Salts and synthetic polymeric materials may be further included, and the type and content thereof may be appropriately adjusted according to the purpose and purpose of use of the final product.

In addition, the composition of the present invention may be one containing a solvent commonly included in the form to be applied, for example, ethanol, glycerin, butylene glycol, propylene glycol, polyethylene glycol, 1,2,4-butanetriol, sorbitol Ester, 1,2,6-hexanetriol, benzyl alcohol, isopropanol, butanediol, diethylene glycol monoethyl ether, dimethylisosorbide, N-methyl-2-pyrrolidone, propylene carbonate, glycerin-26, methyl 1 type selected from glutes-20, isocetyl myristate, isocetyl octanoate, octyl dodecyl myristate, octyl dodecanol, isostearyl isostearate, cetyl octanoate and neopentyl glycol dicaprate It may contain the above. When the composition of the present invention is prepared using such a solvent, the solubility of the compound in the solvent varies slightly depending on the kind of the compound and the mixing ratio of the solvent. The type and amount of usage can be selected and applied appropriately.

In addition, the compositions of the present invention may include various materials for enhancing transdermal penetration during transdermal administration. For example, lauroamram derivatives and oleic acid, ester derivatives of monooleate derivatives, adapalene, tritinoin, retinaldehyde, tazarotine, salicylic acid, aziraic acid, glycolic acid, ethoxydiglycol, twin 80, lecithin organogel, and the like. In addition, the composition of the present invention, in order to impart additional functions, co-surfactant, surfactant, anti-dandruff, keratin softener, blood circulation promoter, cellular active agent within the range that does not impair the effect of the composition imparting the moisturizing effect of the present invention Supplementary ingredients, such as fresheners, moisturizers, antioxidants, pH adjusters and purified water, may be added, and may contain additives such as flavors, pigments, preservatives, excipients, etc., depending on the form applied.

In another aspect, the present invention provides a silk peptide fraction having a remarkably excellent skin moisturizing ability. The silk peptide fraction having remarkably excellent moisturizing properties is preferably 60 to 78% (v / v), more preferably 50 to 95% (v / v), preferably 50 to 78% (v / v), of silk peptides. Preferably, the precipitate fraction may be obtained by adding and mixing methanol and / or ethanol aqueous solution at a concentration of 62 to 78% (v / v). As mentioned above, the silk peptide precipitate fraction obtained using an aqueous ethanol solution of 62 to 78% (v / v), in particular about 70% (v / v) concentration, is used in different solutions or the supernatant fraction under the same conditions. It was shown to have a very good water retention in comparison with.

In the case of the skin improvement composition containing the silk peptide fraction having excellent moisturizing ability according to the present invention, it has an excellent effect on improving skin moisture retention ability, and also has workability and applicability in applying skin. The skin moisturizing composition containing the silk peptide fraction does not have any side effects and stickiness of the skin, and forms a moisturizing film on the surface of the skin for a long time, thereby exhibiting excellent and continuous moisturizing effect and improving skin roughness and preventing skin aging.

Hereinafter, a matter of obtaining a silk peptide fraction having excellent moisturizing ability of the present invention and a composition for improving skin having excellent moisturizing ability using the same will be described in more detail with reference to Examples and Test Examples. However, these examples are merely illustrative of the present invention, and the scope of the present invention is not limited thereto.

[ Example ]

Example  1: using 90% aqueous ethanol solution Silk Peptide  Preparation of Fractions

5.0 g of silk peptide (Sindo Biosilk, Korea) was added to 60 ml of a 9: 1 mixed solution of ethanol (54 ml) and water (6 ml) and shaken slowly for at least 6 hours. The ethanol mixed aqueous solution was placed in a centrifuge container, and then centrifuged at 3,000 rpm for 3 minutes to separate the precipitate fraction and the supernatant fraction. Each precipitate fraction and supernatant fractions separated were added with 200 ml of secondary distilled water, placed in a low temperature freezer, completely frozen, and then lyophilized for at least 3 days to obtain 4.0 g of precipitated fraction powder and 0.9 g of supernatant fraction powder. Stored in the refrigerator.

Example  2: using 80% ethanol aqueous solution Silk Peptide  Preparation of Fractions

5.0 g of silk peptide (Sindo Biosilk, Korea) was added to 60 ml of a mixed solution of ethanol (48 ml) and water (12 ml) 8: 2 and shaken slowly for at least 6 hours. The ethanol mixed aqueous solution was placed in a centrifuge container and centrifuged at 3,000 rpm for 3 minutes to separate the precipitates and the supernatant fractions. Each precipitate fraction and supernatant fractions separated were added with 200 ml of secondary distilled water and placed in a freezer, completely frozen, and then lyophilized for at least 3 days to obtain 3.1 g of precipitated fraction powder and 1.8 g of supernatant fraction powder. Stored in the refrigerator.

Example  3: using 70% aqueous ethanol solution Silk Peptide  Preparation of Fractions

5.0 g of silk peptide (Sindo Biosilk, Korea) was added to 60 ml of a mixed solution of ethanol (42 ml) and water (18 ml) 7: 3 and shaken slowly for at least 6 hours. The ethanol mixed aqueous solution was placed in a centrifuge container, and then centrifuged at 3,000 rpm for 3 minutes to separate the precipitate fraction and the supernatant fraction. Each of the precipitate fraction and the supernatant fractions were separated by adding 200 ml of secondary distilled water, and then completely frozen in a freezer, and then lyophilized for at least 3 days to obtain 2.7 g of precipitated fraction powder and 2.1 g of supernatant fraction powder. Stored in the refrigerator.

Example  4: using 60% aqueous ethanol solution Silk Peptide  Preparation of Fractions

5.0 g of silk peptide (Sindo Biosilk, Korea) was added to 60 ml of a mixed solution of ethanol (36 ml) and water (24 ml) 6; 4 and shaken slowly for at least 6 hours. The ethanol mixed aqueous solution was placed in a centrifuge container, and then centrifuged at 3,000 rpm for 3 minutes to separate the precipitate fraction and the supernatant fraction. Each precipitate fraction and the supernatant fractions separated were added with 200 ml of secondary distilled water and placed in a low temperature freezer to completely freeze, followed by lyophilization for at least 3 days to obtain 1.5 g of precipitated fraction powder and 3.4 g of supernatant fraction powder. Stored in the refrigerator.

Example  5: using 50% aqueous ethanol solution Silk Peptide  Preparation of Fractions

5.0 g of silk peptide (Sindo Biosilk, Korea) was added to 60 ml of a mixed solution of ethanol (30 ml) and water (30 ml) 5: 5 and shaken slowly for at least 6 hours. The ethanol mixed aqueous solution was placed in a centrifuge container, and then centrifuged at 3,000 rpm for 3 minutes to separate the precipitate fraction and the supernatant fraction. Each precipitate fraction and supernatant fractions separated were added with 200 ml of secondary distilled water, placed in a freezer, completely frozen, and then lyophilized for 3 days or longer to obtain 0.3 g of precipitated fraction powder and 4.3 g of supernatant fraction powder. Stored in the refrigerator.

Test Example  One: Silk Peptide  Determination of Water Retention Capacity of Fractions

Each fraction obtained by water-ethanol precipitation and silk peptide without any treatment were dissolved in a 5% glycerin solution, and 1 ml of the solution was added dropwise to a cotton pad, and at 30 ° C to 1 hour intervals at 24 ° C and 45 to 50% RH. The change in weight was measured.

The result obtained above is shown in FIG. As can be seen in FIG. 1, for fractions obtained by precipitation under water: ethanol = 3: 7 (70% ethanol aqueous solution) mixing ratio conditions, blank (buffer solution), silk peptide without any treatment, and other water: Compared with the precipitates and supernatants obtained under the ethanol mixing ratio, the water retention ability was remarkable, especially after 360 minutes. As a result, the supernatant in the water: ethanol = 3: 7 mixing ratio condition was found to have a much lower water retention than the silk peptide treated group without any treatment. These results demonstrate that the moisturizing fraction and the bad fraction were separated under water: ethanol = 3: 7 mixing conditions.

Test Example  2: Silk Peptide  Determination of Moisturizing Capacity of Fractions

In order to compare the moisturizing effect of cosmetics with the inclusion of the silk peptide fraction, the moisturizing ability in human skin was measured with several combinations.

That is, lorracerose hydra cream (Cyclomethicone, Betaine, Sodium Hyaluronate, Glycerin, Neopentyl Glycol Dicaprate, Suqalane, Propylene Glycol, Cetearyl Alcohol, Sorbitan Stearate, PEG-40 Stearate, Beeswas , Stearic Acid, Lanolin Wax, Glyceryl Stearate, PEG-100 Stearate, Dimethicone, Tocopheryl Acetate, Arbutin, Coptis Japonica Root Extract, Morus Bombycis Root Extract, Aloe Barbadensis Leaf Juice, Carbomer, Xanthan Gum, Methylparaben, Fragrance, Propylparaben, Triethanolamine Formulations containing 1% silk peptide without any treatment and no treatment with Disodium EDTA, Imidazolidinyl Urea, Acid Green 1), and 1% precipitation fraction with water: ethanol = 3: 7 after preparing the three kinds of formulations after rubbing well after applying a predetermined amount (0.03g / 16m ²⁾ of each composition on the inside forearm blood tester, coated before coating after 1 hour, 2 hours after the coating, the coating 3 The moisture content of the skin was measured by using a Courage + Khazaka Germany after Corneometer CM825 measuring the skin's electrical conductivity between.

At the time of application, all three formulations did not differ in spreadability or stickiness, and after application, there were no skin abnormalities such as erythema and itching.

The result obtained above is shown in FIG. As can be seen in Figure 2, in the case of the formulation containing the fraction obtained by precipitating under water: ethanol = 3: 7 conditions, even after 3 hours compared to the formulation containing the silk peptide without addition group or fraction extraction Statistically significant level of skin conductivity was shown, which shows that the fraction obtained by precipitation under water: ethanol = 3: 7 condition shows an excellent effect of increasing skin moisture content.

Figure 1 shows the results of measuring the water retention of each fraction of the silk peptide according to the present invention.

Figure 2 shows the result of measuring the moisturizing ability of the silk peptide fraction according to the present invention.

Claims (14)

It contains the precipitate fraction obtained by adding a mixed solvent of water and an organic solvent to the silk peptide as an active ingredient, The organic solvent is one or more selected from the group consisting of methanol, ethanol, and isopropanol, The content of the organic solvent in the mixed solvent is 60 to 78% (v / v), Moisturizing cosmetic composition. The cosmetic composition according to claim 1, wherein the content of the organic solvent in the mixed solvent is 62 to 78% (v / v). delete The cosmetic composition according to claim 1, wherein the organic solvent is one or more selected from the group consisting of methanol and ethanol. The cosmetic composition according to claim 1, which is applied to skin, scalp or hair. It contains the precipitate fraction obtained by adding a mixed solvent of water and an organic solvent to the silk peptide as an active ingredient, The organic solvent is one or more selected from the group consisting of methanol, ethanol, and isopropanol, The content of the organic solvent in the mixed solvent is 60 to 78% (v / v), Pharmaceutical composition for preventing or treating dry skin. The pharmaceutical composition of claim 6, wherein the content of the organic solvent in the mixed solvent is 62 to 78% (v / v). delete The pharmaceutical composition of claim 6, wherein the organic solvent is one or more selected from the group consisting of methanol and ethanol. The pharmaceutical composition of claim 6, wherein the skin dryness is at least one selected from the group consisting of skin cracking, erythema, itching, psoriasis, and atopy. Silkpeptide precipitate having excellent moisturizing power obtained by precipitating silk peptide with at least one solvent selected from the group consisting of 60 to 78% (v / v) aqueous methanol solution and 60 to 78% (v / v) aqueous ethanol solution Fraction. 12. The silk peptide precipitate fraction according to claim 11, wherein the solvent is 62-78% (v / v) aqueous methanol solution or 62-78% (v / v) aqueous ethanol solution. Adding and mixing a mixed solvent of water and an organic solvent to the silk peptide, and then precipitating and obtaining the precipitate fraction obtained by the electric charging, The organic solvent is one or more selected from the group consisting of methanol, ethanol, and isopropanol, The content of the organic solvent in the mixed solvent is 60 to 78% (v / v), Silkpeptide fraction production method with excellent moisturizing power. The method of claim 13, wherein the mixed solvent is 62-78% (v / v) aqueous methanol solution or 62-78% (v / v) aqueous ethanol solution.

Images