CN114948824A

CN114948824A - Whitening and freckle removing composition

Info

Publication number: CN114948824A
Application number: CN202210867974.4A
Authority: CN
Inventors: 蔡文; 赵肃清; 李立香; 刘楚华; 宋园
Original assignee: Guangzhou Jiarui New Material Technology Co ltd
Current assignee: Guangzhou Jiarui New Material Technology Co ltd
Priority date: 2022-07-21
Filing date: 2022-07-21
Publication date: 2022-08-30

Abstract

The invention relates to the field of cosmetics, and particularly relates to a whitening and freckle-removing composition. In a first aspect, the present invention provides an Pterocarpus marsupium bark extract having a whitening and spot-removing effect. In a second aspect, the present invention provides a whitening and spot-removing composition containing Pterocarpus marsupium bark extract and 4-butylresorcinol. Experiments show that the composition has a good synergistic effect, the use amount of each whitening active substance in the cosmetics can be reduced, and the mildness of the product is improved due to the addition of a small amount of whitening raw materials.

Description

Whitening and freckle removing composition

Technical Field

The invention relates to the field of cosmetics, and particularly relates to a whitening and freckle-removing composition.

Background

Melanin is a major cause of skin pigmentation in humans. The molecular mechanism of action of most whitening raw materials is to improve skin color by reducing the production of melanin; among them, inhibition of tyrosinase activity is one of the main strategies for reducing melanin production. However, some traditional effective whitening raw materials such as kojic acid and hydroquinone can cause side effects such as skin sensitivity and canceration after long-term use. Therefore, the use of novel whitening agents, plant extracts and active ingredients thereof to inhibit tyrosinase activity has increasingly promising application prospects (Naqian, Wuhua, jin Jianming. cosmetic plant material (II) — research and development of plant whitening material for inhibiting tyrosinase activity [ J ] daily chemical industry, 2021,51(03): 178-.

Butyl Resorcinol C ₁₀ H ₁₄ O ₂ It is a resorcinol derivative, has an inhibitory effect on tyrosinase and tyrosinase-related proteins, can reduce the generation of melanin and pigmentation, has attracted more and more attention as a novel hypopigmentation agent, and has been used as a whitening additive for skin care products in recent years. However, 4-butylresorcinol can cause skin irritation, especially when used at high concentrations (Green synthetic Process study of Potiria petiolata.4-n-butylresorcinol [ D ]]Beijing university of chemical industry, 2021.).

Disclosure of Invention

The first aspect of the present invention is directed to provide an Pterocarpus marsupium bark extract having whitening and spot-removing effects.

In order to achieve the above object, the present invention provides the following technical solutions:

an Pterocarpus marsupium bark extract is prepared by extracting as follows:

(1) pulverizing Pterocarpus marsupium bark, and soaking in ethanol water solution; loading into a percolation column, and eluting with ethanol water solution to obtain an eluent; adding activated carbon, stirring at a constant temperature, and filtering to obtain a decolorized solution;

(2) regulating the pH of the decolorized solution to acidity, standing, and filtering to obtain a filtrate;

(3) adjusting the pH of the filtrate to be neutral, adding n-hexane, uniformly mixing, standing for layering, and taking the lower-layer liquid; performing rotary evaporation to recover ethanol to obtain a concentrated solution;

(4) loading macroporous adsorbent resin into column by wet method, sampling the concentrated solution until adsorption is saturated, washing with water, eluting with ethanol water solution, and collecting eluate;

(5) vacuum concentrating to dry, and pulverizing to obtain powder, i.e. Pterocarpus marsupium bark extract.

In some of these embodiments, the aqueous ethanol solution has a concentration of 60-80% by volume.

In some of these embodiments, the resting is at 1-5 ℃ for 12-24 hours.

In some of these examples, the n-hexane is added in an amount of 1 to 5 times the filtrate.

In some of these embodiments, the macroporous resin may be AB-8 or D101.

In a second aspect, the present invention is directed to a whitening and spot-removing composition containing Pterocarpus marsupium bark extract and 4-butylresorcinol.

The whitening and freckle-removing composition contains Pterocarpus marsupium bark extract and 4-butyl resorcinol, wherein the mass ratio of the Pterocarpus marsupium bark extract to the 4-butyl resorcinol is 1: (10-100).

The cosmetic has various dosage forms, wherein the water aqua is an important dosage form, such as essence, facial mask liquid, toning lotion and the like. In order to increase the application range of the whitening and freckle-removing composition, the embodiment of the invention provides a technical scheme of cyclodextrin coating treatment.

A whitening and freckle-removing composition coated by cyclodextrin is prepared by the following process:

(1) putting 10-30 parts by weight of hydroxypropyl beta-cyclodextrin into 60-80 parts by weight of water, and dissolving the mixture until the mixture is completely transparent under stirring to obtain liquid A;

(2) dissolving the whitening and freckle-removing composition in 5-15 parts by weight with a proper amount of ethanol until the composition is completely transparent to obtain liquid B;

(3) slowly adding the liquid B into the liquid A under stirring, keeping the temperature at 40-50 ℃, stirring for 1-2 hours, then putting the materials into a spray dryer, and carrying out spray drying to obtain the whitening and freckle-removing composition coated by the cyclodextrin.

The embodiment of the invention also provides whitening essence which is prepared from the following raw materials in percentage by mass: 5% of glycerol, 5% of pentanediol, 1% of betaine, 0.03% of sodium hyaluronate, 0.05% of xanthan gum, 0-262% of glyceryl polyether, 3% of PEG/PPG/polytetramethylene glycol-8/5/3 glycerol, 1% of PEG/PPG-14/7 dimethyl ether, 0.1% of acrylic acid (ester)/C10-30 alkanol acrylate cross-linked polymer, 0.1% of arginine, 5% of the whitening and freckle-removing composition wrapped by cyclodextrin and the balance of water.

The technical scheme provided by the embodiment of the invention has the following beneficial effects:

(1) the invention provides an Pterocarpus marsupium bark extract with whitening and freckle removing effects and a preparation method thereof. The preparation method is operated at room temperature, and thermosensitive components are kept as much as possible; removing impurities in the extract as much as possible by means of acid precipitation, activated carbon adsorption decoloration, n-hexane extraction and the like, and then separating and purifying by adopting macroporous resin to obtain the Pterocarpus marsupium bark extract. Experiments show that the Pterocarpus marsupium bark extract has good whitening effect.

(2) The invention provides a whitening and freckle-removing composition which contains 4-butyl resorcinol and an Pterocarpus marsupium bark extract. Experiments show that the composition has good synergistic effect, so that the use amount of each whitening active substance in cosmetics can be reduced, and the mildness of the product is improved by adding a small amount of whitening raw materials.

(3) The invention also provides a whitening and freckle-removing composition wrapped by cyclodextrin, the whitening and freckle-removing composition is wrapped in the cyclodextrin, so that the composition has good water solubility, and the application range of the composition is expanded; the cyclodextrin inclusion has a slow release effect, and after the product is applied to the skin of a human body, the active ingredients can not be in full contact with the skin at one time, so that the irritation of the product is reduced; in addition, the retention time of the active ingredients on the skin can be prolonged, the utilization rate of the active ingredients is improved, and the whitening and freckle removing effects are better.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art are briefly introduced below.

Fig. 1 volunteers compared the change before and after using the whitening essence of example 8.

Detailed Description

The present invention will now be described in detail with reference to specific examples, but the scope of the present invention is not limited thereto.

Materials, reagents and the like used in examples of the present invention were commercially available unless otherwise specified.

The Pterocarpus marsupium is the nodular Pterocarpus marsupium. Native to india and srilanka, are mainly distributed in deciduous tropical forests, tend to be evergreen in bangladesh, and can reach as high as 1100 meters at altitude, but are most common in 350-. The bark is grey, coarse, 1.2-1.8 cm thick, longitudinally split, flaky, and has a whitish trace when scraped, while older plants exude a reddish-black resin. The bark, flower, leaf and heartwood of trees all have medical application. The bark can be used as astringent for toothache, the leaves can be used for external application for scald and certain skin diseases, and the flowers can be used for treating fever. Heartwood can be used for treating blood sugar, cholesterol, arthritis and reducing weight. The cosmetic standard for the referred rosewood bark extract is referred to herein as: pterocarpus MARSUPIUM (Pterocarpus MARSUPIUM) bark extract.

Example 1

An Pterocarpus marsupium bark extract is prepared by extracting as follows:

(1) pulverizing Pterocarpus marsupium bark to more than 30 meshes, soaking with 60% (V/V) ethanol water solution overnight, wherein the liquid level is slightly higher than the material; loading into percolation column, eluting with 60% (V/V) ethanol water solution for 1BV to obtain eluate; adding activated carbon accounting for 5% of the weight of the eluent, keeping the temperature at 50 ℃, stirring for 60 minutes, and filtering to obtain a decolored solution;

(2) adding hydrochloric acid into the decolorized solution to adjust the pH value to 1, standing for 12 hours at the temperature of 5 ℃, and filtering to obtain a filtrate;

(3) adding sodium hydroxide into the filtrate to adjust the pH value to be neutral, adding normal hexane with the weight 1 time that of the filtrate, uniformly mixing, standing for layering, and taking the lower-layer liquid; performing rotary evaporation to recover ethanol to obtain a concentrated solution;

(4) loading AB-8 macroporous adsorbent resin into a column by a wet method, loading a concentrated solution at the speed of 2BV/h, washing with 3BV water after adsorption saturation, eluting for 3BV with 60% (V/V) ethanol water solution at the speed of 2BV/h, and collecting an eluent;

Example 2

An Pterocarpus marsupium bark extract is prepared by extracting as follows:

(1) pulverizing Pterocarpus marsupium bark to more than 30 meshes, soaking with 80% (V/V) ethanol water solution overnight, wherein the liquid level is slightly higher than the material; loading into percolation column, eluting with 80% (V/V) ethanol water solution for 2BV to obtain eluate; adding activated carbon accounting for 1% of the weight of the eluent, keeping the temperature at 60 ℃, stirring for 30 minutes, and filtering to obtain a decolorized solution;

(2) adding hydrochloric acid into the decolorized solution to adjust the pH to 2, standing for 24 hours at the temperature of 1 ℃, and filtering to obtain a filtrate;

(3) adding sodium hydroxide into the filtrate to adjust the pH value to be neutral, adding n-hexane with the weight 5 times that of the filtrate, uniformly mixing, standing for layering, and taking the lower-layer liquid; performing rotary evaporation to recover ethanol to obtain a concentrated solution;

(4) loading the D101 macroporous adsorption resin into a column by a wet method, loading a concentrated solution at the speed of 1BV/h, washing with 5BV of water after saturation adsorption, eluting with 80% (V/V) ethanol aqueous solution at the speed of 1BV/h for 4BV, and collecting the eluent;

Example 3

An Pterocarpus marsupium bark extract is prepared by extracting as follows:

(1) pulverizing Pterocarpus marsupium bark to more than 30 meshes, soaking with 75% (V/V) ethanol water solution overnight, and loading into percolation column with liquid level slightly higher than the material; eluting with 75% (V/V) ethanol water solution for 1BV to obtain eluent; adding activated carbon accounting for 3% of the weight of the eluent, keeping the temperature at 55 ℃, stirring for 40 minutes, and filtering to obtain a destaining solution;

(2) adding hydrochloric acid into the decolorized solution to adjust the pH to 1.5, standing for 18 hours at the temperature of 3 ℃, and filtering to obtain a filtrate;

(3) adding sodium hydroxide into the filtrate to adjust the pH value to be neutral, adding n-hexane with the weight 3 times that of the filtrate, uniformly mixing, standing for layering, and taking the lower-layer liquid; performing rotary evaporation to recover ethanol to obtain a concentrated solution;

(4) loading the D101 macroporous adsorption resin into a column by a wet method, loading a concentrated solution at the speed of 1.5BV/h, washing with 4BV water after saturation adsorption, eluting with 75% (V/V) ethanol water solution at the speed of 1.5BV/h for 3.5BV, and collecting the eluent;

Comparative example 1

An Pterocarpus marsupium bark extract is prepared by extracting as follows:

(1) pulverizing Pterocarpus marsupium bark to more than 30 meshes, soaking with 75% (V/V) ethanol water solution overnight, wherein the liquid level is slightly higher than the material; loading into percolation column, eluting with 75% (V/V) ethanol water solution for 1BV to obtain eluate; adding activated carbon accounting for 3% of the weight of the eluent, keeping the temperature at 55 ℃, stirring for 40 minutes, and filtering to obtain a destaining solution;

(3) adding sodium hydroxide to the filtrate to adjust the pH value to be neutral, and performing rotary evaporation to recover ethanol to obtain a concentrated solution;

Test 1 tyrosinase Activity test

Tyrosinase is a key enzyme in skin melanin biosynthesis, acting on dopa to form dopaquinone, which spontaneously undergoes a series of reactions to finally form melanin. Tyrosinase catalyzes the conversion of dopa to dopaquinone in a phosphoric acid solution with a pH of 6.8, and the absorbance can be measured at 475nm of a spectrophotometer. The raw material with tyrosinase activity inhibition effect can reduce the conversion of dopa into dopaquinone, thereby reducing the light absorption value, and the inhibition effect of the raw material on tyrosinase activity is evaluated according to the change of the light absorption value.

The tyrosinase activity inhibition rate of the whitening and freckle-removing composition is determined according to the method recorded in the T/SHRH 015-2018 cosmetic-tyrosinase activity inhibition experiment method, and kojic acid is used as a positive control. The samples to be tested were first dissolved in ethanol and then diluted with disodium hydrogen phosphate-citric acid buffer, and the tyrosinase inhibitory activity of each sample was compared as shown in table 1 below.

TABLE 1 IC50 values for inhibition of tyrosinase activity for each sample

Test sample	Active substance	IC ₅₀
			Sample 1	EXAMPLE 1 Pterocarpus marsupium bark extract	0.31mg/mL
Sample 2	EXAMPLE 2 Pterocarpus marsupium bark extract	1.24mg/mL
			Sample 3	EXAMPLE 3 Pterocarpus marsupium bark extract	0.62mg/mL
Sample No. 4	Comparative example 1 Pterocarpus marsupium bark extract	21.45mg/mL
			Sample No. 5	Positive control-kojic acid	0.12mg/mL

As can be seen from table 1 above, the tyrosinase inhibitory ability of the Pterocarpus marsupium bark extract prepared by the example of the present invention is close to that of kojic acid, and a good effect is obtained. And sample 4 degreased without n-hexane has a weak tyrosinase inhibition rate. This is because part of the nonpolar components such as fats and fatty acids remaining in the decolorized solution have a weakening effect on the separation and purification of the active ingredients in the subsequent process steps.

Example 4

(1) 4-butyl resorcinol and the Pterocarpus marsupium bark extract obtained in example 1 were mixed in the following ratio of 10: 1, and uniformly mixing the components in a weight ratio to obtain the whitening and freckle-removing composition;

(2) adding 10 parts by weight of hydroxypropyl beta-cyclodextrin into 60 parts by weight of water, and dissolving the mixture until the mixture is completely transparent under stirring to obtain liquid A;

(3) dissolving 5 parts by weight of the whitening and freckle-removing composition by using a proper amount of ethanol until the composition is completely transparent to obtain liquid B;

(4) slowly adding the liquid B into the liquid A under stirring, keeping the temperature at 50 ℃ and stirring for 1 hour, then putting the materials into a spray dryer, and carrying out spray drying to obtain the whitening and freckle-removing composition coated by the cyclodextrin.

Example 5

(1) 4-butyl resorcinol and the Pterocarpus marsupium bark extract obtained in example 2 were mixed in a ratio of 100: 1, and uniformly mixing the components in a weight ratio to obtain the whitening and freckle-removing composition;

(2) adding 30 parts by weight of hydroxypropyl beta-cyclodextrin into 80 parts by weight of water, and dissolving the mixture until the mixture is completely transparent under stirring to obtain liquid A;

(3) dissolving 15 parts by weight of the whitening and freckle-removing composition by using a proper amount of ethanol until the composition is completely transparent to obtain liquid B;

(4) slowly adding the liquid B into the liquid A under stirring, keeping the temperature at 40 ℃, stirring for 2 hours, then putting the materials into a spray dryer, and carrying out spray drying to obtain the whitening and freckle-removing composition coated by the cyclodextrin.

Example 6

(1) 4-butyl resorcinol and the Pterocarpus marsupium bark extract obtained in example 3 were mixed in a 50: 1, and uniformly mixing the components in a weight ratio to obtain the whitening and freckle-removing composition;

(2) adding 20 parts by weight of hydroxypropyl beta-cyclodextrin into 70 parts by weight of water, and dissolving the mixture until the mixture is completely transparent under stirring to obtain liquid A;

(3) dissolving 10 parts by weight of the whitening and freckle-removing composition by using a proper amount of ethanol until the composition is completely transparent to obtain liquid B;

(4) slowly adding the liquid B into the liquid A under stirring, keeping the temperature at 45 ℃ and stirring for 2 hours, then putting the materials into a spray dryer, and carrying out spray drying to obtain the whitening and freckle-removing composition coated by the cyclodextrin.

Test 2 stability test

The whitening and spot-removing composition coated with cyclodextrin obtained in examples 4 to 5 was dissolved in a solvent, and uncoated 4-butyl phenol and the bark extract of Pterocarpus marsupium obtained in example 3 were used as a control group. Dividing the tested sample into three parts, respectively placing at 45-15 ℃ and room temperature for 1 month, and inspecting whether the sample has abnormal discoloration. The stability results for each sample are shown in table 2 below.

Table 2 stability record of test samples

As shown in table 2 above, 4-butylresorcinol is at risk of discoloration when stored at room temperature and 45 degrees for a long time, and the whitening and spot-removing composition coated with cyclodextrin, prepared in embodiments 4-5 of the present invention, can alleviate the discoloration phenomenon, and has better stability.

Test 3 Patch to human skin test

The human body skin patch test is used for testing whether a sample has potential adverse reaction on human skin, and is an effective means for detecting the skin irritation of a product. The procedure of skin-closed patch test was organized and tested in 33 volunteers in compliance with the technical Specification for cosmetic safety (2015 edition) chapter seven test for human safety. The whitening and spot-removing composition coated with cyclodextrin obtained in examples 4 to 5 was dissolved in a solvent, and uncoated 4-butyl phenol and the bark extract of Pterocarpus marsupium obtained in example 3 were used as a control group. Using a liquid transfer device to take 0.020mL-0.025mL of test solution in a chamber of a spot tester, and using the thinner of the cosmetic in a control hole. The spot test device with the test substance is applied to the back or the forearm curve of the subject with hypoallergenic tape, and is applied to the skin uniformly by pressing with the palm for 24 h. Skin reactions were observed at 30min (after disappearance of the indentation), 24h and 48h after removal of the test article plaque test apparatus, respectively, according to the criteria of table 1. And the observations were recorded, as detailed in table 3.

TABLE 3 skin reaction record chart for skin-enclosed patch test of each test sample

As can be seen from table 3 above, 4-butylresorcinol has potential adverse reactions on skin, while the whitening and spot-removing composition coated by cyclodextrin, prepared in examples 4-6 of the present invention, has no adverse reactions on skin and is better in mildness.

Example 7

The whitening essence consists of the following raw materials in percentage by mass: 5% of glycerin, 5% of pentanediol, 1% of betaine, 0.03% of sodium hyaluronate, 0.05% of xanthan gum, 262% of glyceryl polyether, 3% of PEG/PPG/polytetramethylene glycol-8/5/3 glycerin, 1% of PEG/PPG-14/7 dimethyl ether, 0.2% of acrylic acid (ester)/C10-30 alkanol acrylate cross-linked polymer, 2% of jojoba oil, 0.22% of arginine, 5% of the cyclodextrin-coated whitening and freckle-removing composition prepared in example 6 and the balance of water.

The preparation process comprises the following steps: putting water, glycerol, betaine, glyceryl polyether-26, PEG/PPG/polytetramethylene glycol-8/5/3 glycerol, and PEG/PPG-14/7 dimethyl ether into an emulsifying pot, starting low-speed homogenization, slowly scattering acrylic acid (ester)/C10-30 alkanol acrylate cross-linked polymer, then putting xanthan gum and sodium hyaluronate which are wetted by pentanediol in advance into the emulsifying pot, and heating to 85 ℃ under the condition of medium-speed stirring; adding jojoba oil, and homogenizing at high speed for 5 min; adding arginine, and stirring for 30 minutes under the condition of heat preservation; cooling to room temperature, adding the whitening and freckle-removing composition wrapped by cyclodextrin, and stirring uniformly to obtain the whitening and freckle-removing composition.

Comparative example 2

The whitening essence consists of the following raw materials in percentage by mass: 5% of glycerin, 5% of pentanediol, 1% of betaine, 0.03% of sodium hyaluronate, 0.05% of xanthan gum, 0-262% of glyceryl polyether, 3% of PEG/PPG/polytetramethylene glycol-8/5/3 glycerin, 1% of PEG/PPG-14/7 dimethyl ether, 0.2% of acrylic acid (ester)/C10-30 alkanol acrylate cross-linked polymer, 2% of jojoba oil, 0.22% of arginine, 5% of cyclodextrin-coated whitening and freckle-removing composition and the balance of water;

wherein the preparation process of the whitening essence is the same as that of example 7;

the whitening and freckle-removing composition coated by the cyclodextrin is prepared by the following process:

(1) adding 20 parts by weight of hydroxypropyl beta-cyclodextrin into 70 parts by weight of water, and dissolving the mixture until the mixture is completely transparent under stirring to obtain liquid A;

(2) 9.804 parts by weight of 4-butyl resorcinol is dissolved by a proper amount of ethanol until the solution is completely transparent, so as to obtain liquid B;

(3) slowly adding the liquid B into the liquid A under stirring, keeping the temperature at 45 ℃ and stirring for 2 hours, then putting the materials into a spray dryer, and carrying out spray drying to obtain the whitening and freckle-removing composition coated by the cyclodextrin.

Comparative example 3

(2) 0.196 parts by weight of the Pterocarpus marsupium bark extract obtained in example 3 was dissolved in an appropriate amount of ethanol until completely transparent, to obtain liquid B;

Test 4 whitening of human body test

The whitening essence prepared in example 7 and comparative examples 2 to 3 was subjected to human body trial tests according to the freckle-removing whitening efficacy test method which is used by the human body open in the notification of the national drug administration that 7 test methods such as a test method of preservatives in cosmetics are brought into the technical safety standard (2015 edition).

The main operation process is as follows:

(1) volunteers: selecting qualified 99 subjects according to the standard subject selection and exclusion criteria, and dividing into 3 groups according to a random table, wherein each group is divided into 33 persons;

(2) subject restriction: during the test, the tested part must use the test product or the control product provided by the test mechanism, and any other product with the freckle removing and whitening effects or possibly influencing the test result cannot be used; the sun exposure condition can not occur during the test period, and the sun protection work of the test part should be done;

(3) the test substance: whitening essence;

(4) the using method comprises the following steps: the test product is issued by the staff according to the random table, and the use instruction is given to the subject according to the use instruction, so that the subject can be ensured to correctly and continuously use the product for 8 weeks;

(5) test sites: a face;

(6) an instrument device: skin colorimeter: an instrument having color space data that can measure L a b specified by the international commission on illumination (CIE);

(7) the test process comprises the following steps: performing product pre-use skin instrument testing and recording on qualified subjects who enter the group; the same evaluations and tests were performed again 4 weeks, 8 weeks after the product was used. At each visit point, the skin colorimeter was used to measure L, a, b values of the skin in the test site plaque area of the test group and the control group, each test area was tested three times, and the ITA ° value was recorded and calculated. The larger the ITA DEG value of the tested skin area, the lighter the skin color and vice versa.

(8) And (4) performing data statistics, wherein statistical analysis is performed on the data by using statistical analysis software, and the data statistics is shown in table 4.

TABLE 4 ITA DEG value statistics before, after and after 4 and 8 weeks of product use

As can be seen from table 4, the facial ITA ° values increased by 5.8 and 9.17, respectively, after 4 weeks and 8 weeks of use of the product compared to the initial values, and the facial ITA ° values were significantly improved compared to the initial values. The comparative examples 2 to 3, in which 4-butylresorcinol or an extract from Pterocarpus marsupium bark was added alone, had improved the facial ITA degree value, but the improvement effect was not as good as that of example 8.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims

1. The Pterocarpus marsupium bark extract is characterized by being prepared by the following extraction method:

(2) adjusting the pH of the decolorized solution to acidity, standing, and filtering to obtain a filtrate;

2. The Pterocarpus marsupium bark extract according to claim 1, wherein the aqueous ethanol solution has a concentration of 60 to 80% by volume.

3. The Pterocarpus marsupium bark extract according to claim 1, wherein the standing is performed at 1-5 ℃ for 12-24 hours.

4. The Pterocarpus marsupium bark extract according to claim 1, wherein n-hexane is added in an amount of 1 to 5 times as much as the filtrate.

5. The Pterocarpus marsupium bark extract of claim 1, wherein said macroporous resin is AB-8 or D101.

6. A whitening and spot-removing composition comprising the Pterocarpus marsupium bark extract according to any one of claims 1 to 5 and 4-butyl resorcinol, wherein the mass ratio of the Pterocarpus marsupium bark extract to the 4-butyl resorcinol is 1: (10-100).

7. The whitening and freckle-removing composition coated by cyclodextrin is characterized by being prepared by the following process:

(2) dissolving 5-15 parts by weight of the whitening and freckle-removing composition of claim 6 in a proper amount of ethanol until the composition is completely transparent to obtain a liquid B;

8. The whitening essence is characterized by comprising the following raw materials in percentage by mass: 5% of glycerol, 5% of pentanediol, 1% of betaine, 0.03% of sodium hyaluronate, 0.05% of xanthan gum, 0.262% of glyceryl polyether, 3% of PEG/PPG/polytetramethylene glycol-8/5/3 glycerol, 1% of PEG/PPG-14/7 dimethyl ether, 0.1% of acrylic acid (ester)/C10-30 alkanol acrylate cross-linked polymer, 0.1% of arginine, 5% of the cyclodextrin-coated whitening and freckle-removing composition of claim 7 and the balance of water.