KR101844980B1 - External composition for skin containing extract of Salix blinii H.Lev. - Google Patents

Abstract

More particularly, the present invention relates to a composition capable of providing skin aging-preventing effect, skin moisturizing power-improving effect and whitening effect by containing an extract of bean curd refuse.

Description

[0001] The present invention relates to a composition for external application for skin, }

The present invention relates to a composition containing Salix blinii H. Lev. Extract of Jeju, and more particularly, to a composition containing an extract of Willow bean root from Jeju to improve skin aging effect, skin elasticity enhancement effect, And a composition capable of providing an effect of improving the elasticity and improving the skin moisturizing ability.

The human skin undergoes changes due to various internal and external factors as it gets older. In other words, internally, secretion of various hormones that regulate metabolism is reduced, the function of immune cells and the activity of cells are lowered, and the biosynthesis of immune proteins and biocompatible proteins necessary for the living body is reduced, and ozone layer destruction As the content of ultraviolet rays reaching the surface of the sunlight increases and environmental pollution is further intensified, free radicals and active noxious oxygen are increased, so that the thickness of the skin decreases, the wrinkles increase, the elasticity decreases Skin color is grayish, skin troubles occur frequently, and spots, freckles and black blots also increase.

As the aging progresses, the content and arrangement of collagen, elastin, hyaluronic acid and glycoprotein, which constitute the skin, are changed or decreased, and oxidative stress due to free radicals and active noxious oxygen is experienced. In addition, most of the cells constituting the skin undergo aging or ultraviolet rays, Cox-2 (cyclooxygenase), an enzyme that produces a proinflammatory cytokine known to cause inflammation, And the biosynthesis of matrix metalloproteinase (MMP), which is an enzyme that degrades skin tissue, is increased by these inflammatory factors, and nitric oxide (NO) production by iNOS (inducible nitric oxide synthase) Respectively. In other words, there is a decrease in cell activity due to natural endogenous aging and a decrease in the biosynthesis of substrate materials due to microinflammation, an increase in stress due to various harmful environments, and an increase in active coral species caused by sunlight As the degradation and denaturation are accelerated, the skin substrate is destroyed and thinned, and various symptoms of skin aging appear. Therefore, it is a reality that many researches have been conducted on the active ingredients which can prevent and improve such aging phenomena.

Several factors are involved in determining the skin color of a person, including the activity of the melanocyte that makes the melanin pigment, the distribution of blood vessels, the thickness of the skin, and the presence or absence of pigment in and out of the body, such as carotenoids and bilirubin It is important.

Especially, the most important factor is melanin, a melanin pigment produced by various enzymes such as tyrosinase in melanocytes in the human body. The formation of melanin pigment affects genetic factors, hormonal secretion, physiological factors such as stress, and environmental factors such as ultraviolet irradiation.

The melanin pigment produced in the melanocytes of the body skin is a phenolic polymer substance having a complex form of black pigment and protein. It protects skin organs below the dermis by blocking ultraviolet rays irradiated from the sun, and at the same time, free radicals And protects proteins and genes in the skin.

Melanin, which is produced by stress stimuli inside and outside the skin, is a stable substance that does not disappear until the skin is excreted through skin keratinization even if the stress disappears. However, when melanin is produced more than necessary, it induces hypercholesterolemia such as spots, freckles, and dots, resulting in poor cosmetic results.

Today, oriental women prefer white, clean skin like white whites, and this is an important criterion of beauty, so there has been a growing demand for treatment and cosmetic problems for hyperpigmentation.

In response to such demands, substances having ascorbic acid, kojic acid, arbutin, hydroquinone, glutathione, derivatives thereof, or tyrosinase inhibiting activity have been conventionally used in cosmetics or pharmaceuticals, The use thereof is limited due to a whitening effect, a safety problem to the skin, a problem of formulation and stability in combination with cosmetics, and the like.

The most important function of the epidermis located on the outermost part of the skin is to protect against various external stimuli (physical and chemical stimulants such as chemicals, air pollutants, dry environment, ultraviolet rays) , And this protective function can maintain its function only when the stratum corneum composed of keratinocytes is normally formed. The stratum corneum (horney layer), which is the outermost part of the epidermis, is formed from keratinocytes and consists of keratinocytes with complete differentiation and a surrounding lipid layer (J. Invest. Dermatol. 1983; 80: 49). The keratinocyte is a characteristic cell in which the basal cell that continuously proliferates in the lowest epidermis undergoes a stepwise change in morphology and function and is elevated to the surface of the skin. After a certain period of time, This process is called "epidermal cell differentiation" or "keratinization" because the new keratinocyte replaces its function. During keratinization, keratinocytes form the stratum corneum while producing natural moisturizing factors (NMF) and intercellular lipids (ceramides, cholesterol, fatty acids), making the stratum corneum firm and flexible, As shown in Fig.

However, such a stratum corneum can easily lose its function due to excessive skin cleansing, lifestyle factors such as bathing, environmental factors such as dry air and pollutants, and endogenous diseases such as atopic skin and senile skin, Due to the increasing number of factors in the modern age, there has been an increasing tendency in recent years to appeal to people with dry skin symptoms and disorders. Therefore, in order to maintain proper skin moisture, studies have been conducted to supply moisture from the outside or to prevent water loss from the body, and a variety of moisturizers having moisture retention ability have been developed, It is widely used in the area.

Jeju Wild Willow ( Salix blinii H.Lev.) is a Jeju specialty plant. Leaves are 2-5cm long and 3-13mm wide. They are narrow lanceolate or esophagus type. They are acute and narrow. They are covered with roots at first, but fall down. There is a saw tooth. Capsules are 3mm long and have hairs and ripen in summer. Flower is bloomed with leaves in April-May, male and female are diatomaceous, and run on Yuehua. Male flower bract is pointed with oval shape and ends are dark brown, hairy is densely, with 2 stamens and 1 stitch line. The magnetized water is 1-2cm long with hairs on the axis, the bract is elliptical peak, the end is dark brown, the hair is dense, and the millimeter is one, which is longer than ½ of the length. It is long oval, hairy, style is long, and there are four stigma. It reaches 50cm in height and shoots a lot of branches. The young branch has hairs at first but it disappears and the red color turns red. (Korean Patent Application No. 10-2008-0019236). However, the efficacy of the present invention on the skin of the bean curd of Jeju is hardly studied There is no bar, and the effects of anti-aging, moisturizing and whitening on skin have not been reported yet.

Thus, the inventors of the present invention found that the bean curd extract of the present invention can provide anti-aging, skin wrinkle improvement, whitening, and moisturizing effect, and thus completed the present invention.

Accordingly, an object of the present invention is to provide an external composition for skin for anti-aging, skin wrinkle improvement, whitening, and moisturizing improvement by containing a crude extract of Cheju bean.

In order to achieve the above object, the present invention provides an anti-aging external preparation for skin comprising an extract of bean curd refuse as an active ingredient.

In addition, the present invention provides a skin external application composition for promoting skin elasticity comprising an extract of burdock bean as an active ingredient.

The present invention also provides a composition for external application for skin for improving skin wrinkles containing an extract of burdock bean as an active ingredient.

Also, the present invention provides a composition for external application for skin for moisturizing, which comprises an extract of willow boroe as an active ingredient.

In addition, the present invention provides a whitening dermatological external preparation composition containing a crude bean curd extract.

The composition of the present invention can provide anti-aging, skin elasticity enhancement effect, skin wrinkle improvement effect, skin whitening effect, and skin moisturizing effect by containing the bean curd extract.

The composition for external application for skin according to the present invention contains an extract of Potentilla stolonifera var. Quelpaertensis Nakai as an active ingredient.

The bean curd extract of the present invention can be obtained by a method known in the art, and specific examples thereof can be prepared by extracting with water or ethanol after drying the bean curd with sunlight or hot air drying. More specifically, the burrs of Jeju are dried by any method such as natural drying or forced drying, and then finely pulverized. Thereafter, a polar solvent such as water, ethanol, butanol or acetone; Non-polar solvents such as ether, hexane, benzene, chloroform, and ethyl acetate; A mixed solvent of the non-polar solvent and the polar solvent; And the like, or a vegetable oil such as soybean oil or sesame oil, by leaching with an arbitrary method such as cooling, percolation, warming, etc. to obtain a leached product containing the active ingredient. The leaching process varies depending on the type and temperature of the solvent used, and preferably about 0.5 to 72 hours at a temperature close to the reflux temperature of the solvent, in the case of cold beating and percolation. It is preferable to use a tincture, a fluid extract or an extract which has been leached in the functional alcohol.

The composition of the present invention preferably contains the crude bean curd extract in an amount of 0.1 to 20% by weight based on the total weight of the composition. If the content of the active ingredient is less than 0.1% by weight, the effect and effect of the ingredient are insignificant. If the content is more than 20% by weight, there is a problem of skin safety or shape.

The composition of the present invention can be used as a composition for external application for skin for anti-aging, which is excellent in improving skin elasticity and improving wrinkles.

The composition of the present invention can be used as a composition for external application for moisturizing skin, which can enhance the skin barrier function and induce differentiation of dermal keratinocytes.

The composition of the present invention can be used as a whitening composition, which can provide an excellent whitening effect by inhibiting tyrosinase activity and inhibiting the production of melanin.

The composition according to the invention may be formulated containing a cosmetically or dermatologically acceptable medium or base. These are all formulations suitable for topical application, for example as a solution, a gel, a solid, a paste anhydrous product, an emulsion obtained by dispersing an oil phase in water, a suspension, a microemulsion, a microcapsule, a microgranule or an ionic form (liposome) In the form of ionic fibrin dispersions, or in the form of creams, skins, lotions, powders, ointments, sprays or conical sticks. It can also be used in the form of a foam or in the form of an aerosol composition further containing a compressed propellant. These compositions may be prepared according to conventional methods in the art.

In addition, the composition according to the present invention may further comprise at least one selected from the group consisting of fatty substances, organic solvents, solubilizers, thickening agents, gelling agents, softening agents, antioxidants, suspending agents, stabilizing agents, Such as fillers, emulsifiers, emulsifiers, fillers, sequestering agents, chelating agents, preservatives, vitamins, blockers, moisturizers, essential oils, dyes, pigments, hydrophilic or lipophilic active agents, lipid vesicles or any other ingredient commonly used in cosmetics May contain adjuvants commonly used in the field of cosmetics or dermatology. Such adjuvants are introduced in amounts commonly used in the cosmetics or dermatological fields.

In addition, the composition of the present invention may contain a skin absorption promoting substance to increase the skin improving effect.

In addition, the composition of the present invention may contain, in addition to the bean curd extract, other ingredients capable of synergizing the skin protection effect within the range that does not impair the desired anti-aging, moisturizing and whitening effect of the present invention can do.

Hereinafter, the constitution and effects of the present invention will be described in more detail with reference to test examples and formulation examples. However, these test examples and formulation examples are provided for illustrative purposes only for the sake of understanding of the present invention, and the scope and scope of the present invention are not limited by the following examples.

[ Manufacturing example  1] Preparation of Yangmoo

After removing the burdocks from Jeju and washing with purified water, the dried product was dried by 60 hot air drying method. 100 g of the dried product was put into 1 L of 70% ethanol and extracted by cooling at room temperature for 48 hours. Next, the extract was filtered through a 0.45 μm filter paper, and dried at 50 ° C. with a rotary evaporator to obtain 13 g of dry weight.

[ Test Example  1] Elastase activity inhibitory activity measurement

The inhibitory activity of elastase activity of the bean curd extract of the present invention was measured in comparison with EGCG. The elastase and substrate used were commercially purchased (Cat. No. E0127) from Sigma Aldrich, USA, and the chelate weevil extract obtained from Preparation Example 1 was used.

The elastase activity inhibitory activity was tested by the following test method.

To 1 ml of the buffer prepared with 10 mg / L Tris-HCl buffer (pH 8.0) in a 96-well plate, 50 μL of the test substance in which 10 mg of the bean curd extract obtained in Preparation Example 1 was dissolved and 50 μL of 20 μg / mL elastase type III solution . EGCG 250 μM was used as a positive control, and negative control group, distilled water, was used. Then, 100 μL of 0.4514 mg / mL N-SUCCINYL-ALA-ALA-ALA-p-NITROANILIDE prepared as the buffer solution was added and reacted at 25 ° C. for 15 minutes. After completion of the reaction, the absorbance at a wavelength of 415 nm was measured. A blank test was carried out in the same manner and corrected.

The method for calculating the activity of inhibiting the activity of the elastase is shown in the following Equation 1, and the results are shown in Table 1 below.

A: Absorbance at 415 nm at the wavelength of the enzyme addition,

B: absorbance at a wavelength of 415 nm in the absence of the sample added with the enzyme and no addition of the enzyme

C: Absorbance at wavelength 415 nm in addition of experimental sample and enzyme addition

D: absorbance at a wavelength of 415 nm in the addition of an experimental sample and no enzyme addition

compound % Inhibition Untreated group 0 EGCG 65 Jeju raspberry extract 67

As shown in Table 1, the bean curd extract of the present invention showed an effect similar to that of EGCG, which is known as an inhibitor of the activity of inhibiting elastase activity. Thus, the effect of suppressing the elastase activity of the extract of the fermented sea mustard extract of the present invention I can confirm that it is excellent.

[ Test Example  2] Collagenase ( MMP -One) Low performance

The inhibitory effect on the collagenase production of the bean curd extract of the present invention was measured in comparison with retinoic acid.

Human fibroblasts were plated at 5,000 cells / well in a 96-well microtiter plate containing 2.5% fetal calf serum-containing DMEM (Dulbecco's Modified Eagle's Media) And incubated at 37 ° C in an incubator with CO _{2 of} 5% until it grew to about 80%. The extracts of Korean wild burdock were treated at a concentration of 100 ㎍ / ml ㎍ / ml for 24 hours, and cell culture medium was collected.

The degree of collagenase production in the cell culture was measured using a commercially available collagenase assay device (Amersham Pharmacia, USA, Catalog #: RPN 2610). First, the cell culture solution collected on a 96-well plate uniformly coated with primary collagenase antibody was added and the antigen-antibody reaction was performed in a thermostatic chamber for 3 hours. After 3 hours, the second collagen antibody bound to the chromophore was placed in a 96-well plate and reacted for another 15 minutes. After 15 minutes, the color development substance (3,3 ', 5,5'-tetramethylbenzidine, sigma) was added and color development was induced at room temperature for 15 minutes. When 1 M sulfuric acid was added to stop the color development reaction, the color of the reaction solution became yellow And the degree of yellowing was different according to the progress of the reaction.

The absorbance of a yellow 96-well plate was measured at 405 nm using a spectrophotometer and the degree of synthesis of collagenase was calculated by the following equation (2) Respectively. At this time, the reaction absorbance of the cell culture fluid collected from the non-treated group was used as a control.

compound Expression level (%) Untreated group 100 Retinoic acid 75 Jeju raspberry extract 74

As shown in Table 2 above, collagenase expression inhibitory effects of the Jeju bean curd extract are similar to those of retinoic acid, which is known as collagenase expression inhibitor.

From these results, it can be confirmed that the bean curd extract of the present invention has an effect of inhibiting the substrate metalloprotease (MMP-1).

[ Formulation Example  1 and Comparative Formulation Example  One]

Nutritive creams were prepared in a conventional manner according to the composition of Table 3 below (unit: wt%).

Ingredients (% by weight) Formulation Example 1 Comparative Formulation Example 1 Purified water To 100 To 100 Jeju raspberry extract 3 - Vegetable hydrogenated oil 1.50 1.50 Stearic acid 0.60 0.60 Glycerol stearate 1.00 1.00 Stearyl alcohol 2.00 2.00 Polyglyceryl-10pentastearate and behenyl alcohol and sodium stearoyl lactylate 1.00 1.00 Arachidyl behenyl alcohol and arachidyl glucoside 1.00 1.00 Cetylaryl Alcohol and Cetearyl Glucoside 2.00 2.00 PEG-100 Stearate & Glycerololate & Propylene Glycol 1.50 1.50 Caprylic / carboxy triglyceride 11.00 11.00 Cyclomedicone 6.00 6.00 Preservative, incense Suitable amount Suitable amount Triethanolamine 0.1 0.1

 [ Test Example  3] Skin elasticity improvement efficacy confirmation

In order to confirm the skin elasticity improvement effect in human, the formulations of Formulation Example 1 and Comparative Formulation Example 1 were evaluated as follows.

Twenty healthy women in the 30s to 40s were divided into two groups of 10 for each of the two groups of Formulation Example 1 and Comparative Example 1, and the nutritional cream was applied once to the left side for 12 weeks on the left side. Then, SEM 575, C + K Electronic Co., Germany). The results are shown in Table 4 below. The results in Table 4 are reported as ΔR8 (R8 (left) -R8 (right)) of Cutometer SEM 575, where R8 values indicate the properties of viscoelasticity.

Experimental product Skin elasticity effect Formulation Example 1 0.33 Comparative Formulation Example 1 0.10

As shown in Table 4, Formulation Example 1 containing the bean curd extract of the present invention showed more skin elasticity than Comparative Example 1 coated group.

Therefore, it can be confirmed that the composition containing the crude bean curd extract of the present invention is very effective for improving skin elasticity.

[ Test Example  4] Confirmation of skin wrinkle improvement efficacy

Formulation Example 1 and Comparative Formulation Example 1 were used in order to confirm the wrinkle-reducing effect of the composition of the present invention in humans.

In order to confirm the effect of improving the wrinkles of Formulation Example 1 and Comparative Formulation Example 1, the following evaluation was made. Twenty healthy women in their 40s were divided into two groups of 10 each for Formulation Example 1 and Comparative Formulation Example 1 to apply the nutritional cream once a day for 12 weeks to the face, Were visually analyzed by viscometer (SV600, Courage + Khazaka electronic GmbH, Germany). The results are shown in Table 5 below. The values in Table 5 below are the average values obtained by subtracting the pre-application parameter values from the respective parameter values after 12 weeks of application.

After 8 weeks of use
Clinical outcome R1 R2 R3 R4 R5 Formulation Example 1 -0.30 -0.21 -0.14 -0.10 -0.09 Comparative Formulation Example 1 0.27 0.26 0.21 0.03 0.03

R1: Difference between the maximum value and the minimum value of the wrinkle contour line

R2: The wrinkle contour is arbitrarily divided into 5 squares, and the average of R1 values

R3: the highest value of R1 divided by 5

R4: Average value obtained by subtracting the value of each apex and valley from the baseline of the wrinkle contour line

R5: Difference between the baseline of the wrinkle contour line minus the contour of each wrinkle

As shown in Table 5, it was found that the composition for external application for skin of Formulation Example 1 was excellent in the effect of improving skin wrinkles.

[ Test Example  5] Skin Moisture power  Increase effect measurement

In order to measure the effect of the wild burdock extract of Jeju on skin moisturizing ability, Formulation Example 1 and Comparative Formulation Example 1 were used and evaluated as follows.

20 men and women in the 40s and 50s classified as dry skin were divided into two groups of 10 persons for each of Formulation Example 1 and Comparative Formulation Example 1 to apply the nutritional cream twice daily for 4 weeks to the face. (24 ° C, relative humidity 40%) after 1 week, 2 weeks, and 4 weeks after application, and after 2 weeks (total 6 weeks) (Corneometer CM825, C + K Electronic Co., Germany). The results are shown in Table 6 below. The results in Table 6 are based on the skin moisture meter measured immediately before the start of the test, and the increase in the measured value after treatment for a certain period is expressed as a percentage.

Test group Moisture growth rate (%) 1 week Two weeks 4 weeks 6 weeks Formulation Example 1 30 35 39 34 Comparative Formulation Example 1 30 33 36 25

The results of Table 6 show that when Comparative Formulation Example 1 is applied, the moisture increase rate is about 30% until 4 weeks of application, but after the application is stopped, the amount of skin moisture decreases, , It was confirmed that the skin moisture increase rate was 34% or more even after the application was stopped. Thus, it can be seen that the composition of the present invention containing the extract of Jeju mulberry extract is excellent in the skin moisturizing ability maintenance effect.

[ Test Example  6] Measurement of promoting effect of keratinocyte differentiation

In order to investigate the differentiation promoting effect of keratinocyte extracts of Jeju bean curd extract, the amount of corned envelope (CE) produced upon differentiation of keratinocytes was measured using absorbance.

First, keratinocytes of primary cultures isolated from the epidermis of newborn infants were placed in a culture flask and adhered to the bottom. After treating the test substances in Table 7 with the concentration of 5 ppm in the culture medium, The cells were cultured for 5 days until they grew to about 80%. At this time, low calcium (0.03 mM) and high calcium (1.2 mM) treatment groups were negative control and positive control, respectively. Then, the cultured cells were harvested, washed with PBS (Phosphate buffered saline), and then suspended in 10 mM Tris-HCl buffer (Tris-HCl, pH 7.4) containing 2% SDS (sodium dodecyl sulfate) and 20 mM DTT (Dithiothreitol) pH 7.4) was added, sonication, boiling, and centrifugation. The precipitate was suspended again in 1 ml of PBS and the absorbance at 340 nm was measured. Separately, a part of the solution after the sonication was taken to measure the protein content and used as a standard in evaluating the degree of cell differentiation. The results are shown in Table 7 below.

Test substance The ability to differentiate in keratinocytes (%) Low calcium (0.03 mM) solution
(Negative control) 100 High calcium (1.2 mM) solution
(Positive control group) 210 Jeju raspberry extract 180

As shown in Table 7 above, it was confirmed that when the bean curd extract was treated, the effect of accelerating differentiation of keratinocytes was excellent.

[ Test Example  7] Measurement of skin barrier function recovery effect

The following experiment was conducted to determine the effect of Jeju bean curd extract on recovery of damaged skin barrier function due to skin damage. Ten adult male and female adults were injured on the skin barrier using a tape stripping method, and the two groups of Formulation Example 2 and Comparative Formulation Example 2, which were prepared according to the composition shown in Table 8 below, were applied for 7 days The recovery rate of TWEL was measured and compared with Vapometer (Delfin, Finland) once a day. Here, Comparative Formulation Example 2 is a vehicle as a negative control. The experimental results are shown in Table 9 below. The results in Table 9 were compared before treatment before barrier damage and after treatment before barrier damage on the basis of 100%.

Ingredients (% by weight) Formulation Example 2 Comparative Formulation Example 2 Purified water 67 69 Propylene glycol 30 30 Jeju raspberry extract 3 -

Test group TWEL (g / m 2 h) 1hr 2 hr 3hr 4hr 5hr 6hr Formulation Example 2 6.2 6.4 6.5 6.5 6.6 6.8 Comparative Formulation Example 2 8.8 9.0 9.1 9.2 9.3 9.5

As can be seen from the above Table 9, it can be confirmed that when the bean curd extract is treated, the transdermal water loss is prevented at a high rate and the barrier damage is restored.

[ Test Example  8] Whitening effect - Tyrosinase  Inhibitory effect

The tyrosinase enzyme was extracted from Mushroom and was obtained from Sigma (SIGMA). First, the substrate, tyrosine, is dissolved in distilled water to make a 0.3 mg / ml solution. The solution is put into a test tube in an amount of 1.0 ml. Then, 1.0 ml of potassium phosphate buffer solution (0.1 mol concentration, pH 6.8) and 0.7 ml of distilled water .

0.2 ml of each sample liquid prepared by mixing the crude bean curd extract of the present invention at an appropriate concentration in water was added to the reaction solution and reacted in a 37 ° C thermostatic chamber for 10 minutes. At this time, the control group was prepared by adding 0.2 ml of a solvent instead of each sample solution, and ascorbic acid was used as a positive control group. 0.1 ml of tyrosinase solution of 2500 units / ml was added to the reaction solution, followed by reaction at 37 ° C for 10 minutes. The reaction tube was immersed in ice water to quench the reaction, and the absorbance at 475 nm was measured with a photoelectron spectrometer. The results are shown in Table 10 below. Each tyrosinase inhibitory effect was calculated by the following equation (3).

Test substance Inhibition rate of tyrosinase (%) Control group (no addition) 0 Ascorbic acid 52 Jeju raspberry extract 70

From the results of Table 10, it can be seen that the inhibitory effect of tyrosinase of the cosmetic composition containing the bean curd extract of the present invention is more remarkable than that of ascorbic acid, which is a known tyrosinase inhibitor.

[ Test Example  9] Whitening effect - B16 / F10 Melanoma  Inhibitory Effect of Cells on Melanin Production

A sample containing 0.001% by weight of each of the crude bean curd extract and koji acid of Preparation Example 1 was added to the culture medium of B16 / F10 melanoma cells (Korean Cell Line Bank) at a constant concentration as a test substance, and the mixture was cultured for 3 days The culture was removed, washed with PBS, and the cells were lysed with 1N NaOH and absorbance was measured at 405 nm. Cells to which the test substance was not added were used as a control group, and the melanin formation inhibition degree of each test substance was measured by comparing with the melanin content in the control group. The inhibition rate of melanin production was calculated according to Equation (4) and the results are shown in Table 11.

Test substance Melanin production inhibition rate (%) Control group (no addition) 0 Kojic acid 53 Jeju raspberry extract 52

From the results of Table 11, it was confirmed that the inhibitory rate of melanogenesis of the cosmetic composition containing the bean curd extract of the present invention has a whitening effect similar to that of koji acid, which is a well-known melanin formation inhibitor.

Claims (7)

An external skin cosmetic composition for skin whitening comprising an extract of Salix blinii H. Lev. As an active ingredient. [Claim 3] The cosmetic composition for external application for skin according to claim 1, wherein the crude bean curd extract is present in an amount of 0.1 to 20% by weight based on the total weight of the composition. delete A cosmetic composition for external skin application for enhancing skin elasticity comprising an extract of Salix blinii H. Lev. As an active ingredient. A cosmetic composition for external application for skin for improving skin wrinkles containing an extract of Salix blinii H. Lev. As an active ingredient. A cosmetic composition for skin external application for skin moisturizing, comprising an extract of Salix blinii H.Lev. delete