Whitening composition as well as preparation method and application thereof

Abstract

The invention discloses a whitening composition as well as a preparation method and application thereof. The whitening composition is prepared from the following components: a tea leaf extract, a lavender flower extract and water, wherein the tea leaf extract, the lavender flower extract and the water are added into the whitening composition. The whitening composition can interact and synergistically improve the autophagy ability of cells, synergistically improve the phagocytosis of melanin in keratinocytes and the removal ability of skin metabolic wastes, can synergistically inhibit the generation of melanin and synergistically improve the expression of miR-137 genes in melanocytes, has a relatively high development prospect of cosmetics with whitening effects, and has a wide application prospect. Moreover, the composition is mild in property, easy to absorb and non-irritant, and can be widely applied to skin care cosmetics.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of skin external use agents, in particular to a whitening composition, a preparation method and application thereof. BACKGROUND

[0002] Whitening products have always been the products that consumers pursue and love. Common whitening agents in these products are, for example, hydroquinone, kojic acid, arbutin, etc., which have more or less considerable cytotoxicity. Therefore, the safety of tyrosinase inhibitors is a factor that needs to be considered in the development of whitening skin care products. Plant whitening ingredients derived from natural Chinese herbal plants have the advantages of high safety and low cost, and are increasingly popular among consumers.

[0003] Autophagy is a vacuolar self-digestion process that digests long-lived proteins and damaged organelles through lysosomes to produce small molecules such as amino acids that are available to the cell and the organism. Light chain 3 (LC3) can be used as an autophagy marker, which was originally identified as a subunit of microtubule-associated proteins 1A and 1B (referred to as MAP1LC3), and subsequently found to have similarity to the yeast protein Apg8 / Aut7 / Cvt5. There are three human isoforms of LC3, LC3I, LC3II and LC3III, which undergo post-translational modification during autophagy. LC3 is immediately cleaved at the carboxy terminus after synthesis to obtain the cytosolic form LC3I. During autophagy, LC3I is converted to LC3II by lipidation involving the ubiquitin-like system of Apg7 and Apg3, which allows LC3 to bind to autophagic vesicles. Therefore, LC3 is present in autophagosomes, and the conversion of LC3II into a lower migration form can be used as an indicator of autophagy. The autophagy mechanism can ensure proper cell function and body mechanism, delay tissue aging and maintain the overall balance of the skin.

[0004] Melanin determines the changes in skin color associated with racial skin diversity in the epidermis. Keratinocytes derived from Caucasian skin show higher autophagic activity than those from African American skin, and with higher autophagic activity, keratinocytes derived from Caucasian skin are more sensitive to melanin and exhibit enhanced autophagic activity. Lysosomal inhibitors or specific small interfering RNAs related to autophagy can accelerate the accumulation of melanin in keratinocytes. Based on the traditional three-enzyme-one-substance whitening theory, by increasing the autophagy of keratinocytes, the phagocytosis of melanin can be promoted, thereby achieving a better whitening effect. Therefore, autophagy plays a key role in determining skin color by regulating the degradation of melanin in keratinocytes.

[0005] Therefore, it is necessary to develop a plant ingredient composition with low irritation and excellent whitening effect. SUMMARY

[0006] To solve the above technical problems, the present application aims to provide a whitening composition and its preparation method and application.

[0007] The first aspect of the present application provides a whitening composition, wherein the whitening composition comprises the following components: Camelia Sinensis leaf extract, lavender flower extract; wherein the content of the Camelia Sinensis leaf extract is 0.35-0.65% by mass, the content of the lavender flower extract is 35-65%, and deionized water makes up 100%.

[0008] Further, the content of the Camelia Sinensis leaf extract is 0.45-0.55%, and the content of the lavender flower extract is 45-55%.

[0009] The added amount of the composition in cosmetics is 0.01 wt%-5 wt%, preferably 0.5 wt%-1.5 wt%. For example, 0.5 wt%, 0.7 wt%, 1 wt%, 1.2 wt%, 1.5 wt%, % is the percentage of the total mass of the whitening composition and the skin external agent.

[0010] Further, the added amount of the Camelia Sinensis leaf extract in cosmetics is 0.0035 wt%-0.0065 wt%, preferably the added amount of the Camelia Sinensis leaf extract in cosmetics is 0.0045 wt%-0.0055 wt%. For example, 0.0045 wt%, 0.0046 wt%, 0.0048 wt%, 0.005 wt%, 0.0051 wt%, 0.0052 wt%, 0.0055 wt%.

[0011] The added amount of the lavender flower extract in cosmetics is 0.35 wt%-0.65 wt%, preferably the added amount of the lavender flower extract in cosmetics is 0.45 wt%-0.55 wt%. For example, 0.45 wt%, 0.46 wt%, 0.47 wt%, 0.48%, 0.50 wt%, 0.51 wt%, 0.52 wt%, 0.53 wt%, 0.54 wt%, 0.55 wt%.

[0012] Further, the Camelia Sinensis leaf extract is a Camelia Sinensis freeze-dried powder, and the preparation method of the Camelia Sinensis freeze-dried powder comprises the following steps: 1) Extraction: After the Camelia Sinensis leaf is crushed, the solvent is added and heated, and then ultrasonic extraction is performed, and the obtained crude filtrate is centrifuged, and the crude extract is separated at 8000-12000 rpm; 2) filtration and concentration: the crude extract is filtered through a 0.4-0.6 um ceramic membrane, further filtered through a 0.01-1 um ultrafiltration unit to retain macromolecules above 200,000 daltons, and then concentrated 8-10 times through a reverse osmosis unit at a pressure of 2-5 MPa to obtain a small-molecule tea extract; 3) freeze-drying process: the small-molecule tea extract obtained in step is pre-frozen at -50 to -40℃ and then vacuum-frozen to obtain the tea freeze-dried powder.

[0013] characterized in that the solvent used in step 1) is deionized water or glacial water, the feed liquid ratio of the solvent is 1:5-20, and the heating temperature is 85-95℃, In step 3), the pre-freezing includes the following steps: pre-freezing at -50 to -40℃ for 0.5-2h; the vacuum freezing includes the following steps: drying at -35 to -25℃ for 1-6h, drying at -25 to -15℃ for 1-6h, drying at -15 to -5℃ for 1-6h, drying at 5 to 5℃ for 1-6h, drying at 5 to 15℃ for 1-6h, drying at 15 to 35℃ for 1-6h, drying at 35 to 45℃ for 1-6h, drying at 45 to 55℃ for 1-6h, drying at 55 to 65℃ for 1-6h, and the vacuum degree of the drying chamber during drying is 66-300Pa.

[0014] During the vacuum freezing process, the vacuum degree of the drying chamber is controlled at 66-300Pa. The tea liquid solid is in a sublimation state.

[0015] The tea freeze-dried powder obtained by this method has high solubility and can be dissolved in conventional solvents such as water, thereby further improving the uniformity of mixing with lavender flower extract and retaining a high content of tea polyphenols, and has good storage stability.

[0016] Further, the preparation method of the lavender flower extract includes the following steps: a) pre-drying the narrow-leaved lavender flowers and flower stems; b) grinding the pre-dried material obtained in step a) to a particle size range of 500-1mm, adding water and sodium hydroxide to adjust the pH to 10.8, and adding 2g / L or 3mM of phytic acid to obtain a mixture; c) heating the mixture obtained in step b) at 80℃ with stirring to obtain a crude extract; d) adding diatomite to the crude extract obtained in step c), filtering, adjusting the pH to 7.5 with an HC1 solution, sequentially filtering on filters with gradually decreasing porosity, and then adjusting the pH to 6.3 with an HC1 solution to obtain an aqueous extract with a dry weight of 12.6g / kg.

[0017] The lavender flower extract obtained by the method is subjected to chemical analysis and is rich in small RNA, sugar, phenolic compounds and organic acids. Further, the lavender flower extract contains 3.7 g / kg of total sugar, 1160 g / kg of total organic acid, 1270 mg / kg of total phenolic compound and 118 mg / kg of low-molecular-weight RNA with a maximum length of 150 nucleotides.

[0018] When the lavender flower extract obtained by the method is mixed with tea leaf extract, the mutual solubility is good and a good synergistic effect can be achieved.

[0019] Another aspect of the present application provides a preparation method of the whitening composition, comprising the following steps: adding tea (Camelia Sinensis) leaf extract and lavender flower extract into deionized water, dissolving and mixing to obtain.

[0020] Another aspect of the present application provides application of the whitening composition in preparation of a skin external agent.

[0021] Another aspect of the present application provides that the whitening composition is used as an active ingredient for whitening, an active ingredient for improving autophagy ability of cells, an active ingredient for inhibiting melanin and improving phagocytosis of melanin in keratinocytes in a skin external agent.

[0022] Another aspect of the present application provides a skin external agent with the whitening composition, characterized in that the external agent contains 0.5 wt% to 1.5 wt% of the whitening composition, and the % is the percentage of the total mass of the whitening composition and the skin external agent.

[0023] Advantageously: The preparation process of the whitening composition provided by the present application is convenient and can interact. On the basis of the traditional three-enzyme-one-substance whitening theory, the autophagy ability of cells is synergistically improved, the phagocytosis of melanin in keratinocytes and the ability of skin to remove metabolic waste are synergistically improved, melanin production is synergistically inhibited, and the expression of miR-137 gene in melanin cells is synergistically improved. The whitening cosmetic has a high development prospect, and when used, it is mild, easy to absorb and non-irritating, and can be widely applied to skin care cosmetics. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 Example Three (I) Melanin Inhibition Test Inhibition Rate of Melanin Content of Different Samples Figure 2 Example Three (II) LC3 Fluorescence Expression Test LC3 Fluorescence Staining Photos of Different Samples of Ex vivo Skin Figure 3Example three (ii) Fluorescence expression of LC3 to test the level of LC3 expression in different samples in ex vivo skin DETAILED DESCRIPTION

[0025] The present application is further illustrated by the following examples without thereby limiting the application to the examples described. The experimental methods in the following examples, for which no specific conditions are indicated, are carried out according to routine methods and conditions, or according to the instructions of the commercial suppliers.

[0026] Example one Method for the preparation of lavender flower extract 1) Preparation of lavender flower extract containing small RNA Lavender flowers of the Lavandula angustifolia species are pre-dried in a well-ventilated place away from light.

[0027] In a first step, the dried lavender flowers and flower stems are ground to a powder with a particle size range of 800 pm, and 30 g of dried lavender flower powder is added to 968 g of distilled water. Then, 2 g / L or 3 mM of phytic acid is added.

[0028] At the same time, the pH is adjusted to 10.8 by adding soda (NaOH) in order to optimally enrich the extract with low-molecular-weight RNA.

[0029] The mixture is then heated at 80°C for 1 hour with stirring.

[0030] After extraction, diatomite is added to the mixture in order to facilitate the subsequent separation between the solid residual plant material and the extract (soluble fraction). The mixture is then filtered through a filter with a pore size of 30 pm to remove the solid material. The pH is then adjusted to pH 7.5 using an HCI solution.

[0031] Sequential filtration is then carried out on filters with decreasing porosity in order to clarify the plant extract until a 0.2 pm sterilization filter. At the end of this step, the pH is checked and then adjusted to 6.3 using an HCI solution. A pH of 6 and 6.5 preserves the small RNAs in the extract. An aqueous extract with a dry weight of 12.6 g / kg is obtained. The lavender flower extract obtained with this method was subjected to a chemical analysis which showed that the extract obtained had the following concentrations of substances: 3.7 g / kg of total sugars, 1160 g / kg of total organic acids, 1270 mg / kg of total phenolic compounds and 118 mg / kg of low-molecular-weight RNA with a maximum length of 150 nucleotides.

[0032] 2) Preparation of a common water-extracted lavender flower extract: After the lavender flowers have been ground in a pulverizer, the lavender flower powder is mixed with boiling distilled water at a ratio of 1 : 10 (kg:L), and the lavender flower extract is obtained by filtration.

[0033] Example 2 Preparation of tea lyophilized powder After the tea raw material is crushed, solvent glacial water is added at a ratio of 1:10, and the mixture is heated to 85°C and extracted by ultrasonic. The obtained crude filtrate is centrifuged by a flat plate, and separated by high-speed centrifugation at 10,000 rpm. Then, the filtrate is filtered through a 0.4-μm ceramic membrane, and the obtained clear liquid is further filtered through a 0.3-μm ultrafiltration unit to intercept macromolecules above 200,000 daltons. The small-molecule tea extract is concentrated by a reverse osmosis unit (the reverse osmosis pressure is controlled at 3.5 MPa) to obtain a small-molecule tea extract that is 10 times concentrated (the temperature during the filtration process is controlled at <50°C).

[0034] The small-molecule tea extract is pre-frozen at -45°C for 1.5 h, dried at -30°C for 6 h, dried at -20°C for 6 h, dried at -10°C for 6 h, dried at 0°C for 6 h, dried at 15°C for 6 h, dried at 30°C for 6 h, dried at 45°C for 2 h, dried at 50°C for 2 h, and dried at 60°C for 2 h. The water is removed by freeze-drying. Finally, the finished tea lyophilized powder is obtained. The vacuum degree of the drying chamber during the drying process is controlled at 66-300 Pa. The tea liquid solid is in a sublimation state. After inspection, the finished product is filled to obtain a tea lyophilized powder with a tea polyphenol content of more than 25%. The tea lyophilized powder obtained under the freezing conditions can maintain the activity and color of tea polyphenols, and has good mutual solubility and stability with lavender flower extract.

[0035] Example 3 Efficacy test (1) Melanin inhibition test TEA: 0.002 g or 0.005 g of tea lyophilized powder is configured into a 0.002% or 0.005% sample solution with deionized water; NE: Lavender flower extract rich in small RNA obtained by the extraction method of Example 1; B: Common water-extracted lavender flower extract obtained by the extraction method of Example 1; TEA+NE: 0.002 g or 0.005 g of tea lyophilized powder is added with 0.2 g or 0.5 g of NE, and then configured into a 0.002% TEA+0.2% NE or 0.005% TEA+0.5% NE sample solution with deionized water; TEA+B: 0.005 g of tea lyophilized powder is added with 0.5 g of B, and then configured into a 0.005% TEA+0.5% B sample solution with deionized water.

[0036] Test method The content of intracellular melanin was determined by NaOH lysis method. B16 melanoma cells were cultured in 12-well plates at a density of 1X105, after 24 h, the sample powder of Table 1 was dissolved with PBS and filtered to remove bacteria, and then added to the cells, and cultured for 72 h. The supernatant was discarded, the cells were trypsinized and centrifuged to collect the cells into a centrifuge tube, 150 μL of 1 mol / L NaOH solution (containing 10% DMSO) was added, and the cells were fully lysed at 80°C for 1 h. The absorbance at 405 nm was measured. The protein concentration of B16 cells was determined by BCA method for correction of absorbance. The data was expressed as a percentage of the control group.

[0037] Melanin inhibition rate: [A(NC group)-A(sample group)] / A(NC group)*100% A: absorbance of melanin, the larger the A, the more melanin Table 1: Sample and test information

[0038] The test results are shown in Figure 1 According to the results, 0.005% and 0.002% TEA and 0.5% and 0.2% NE have a certain inhibitory effect on the production of melanin in melanocytes; but the composition of 0.005% TEA+0.5% NE has a significant difference in melanin inhibition compared with TEA and NE alone, and the inhibition rate value is greater than the sum of the two monomer inhibition rates, which indicates that the composition at this concentration has a synergistic effect on melanin inhibition, and at 0.002% and 0.2% concentration, the synergistic effect is not obvious, and the lavender flower extract obtained by ordinary water extraction and tea freeze-dried powder at the same concentration have no obvious synergistic effect on melanin inhibition.

[0039] (II) LC3 fluorescence expression test LC3, which stands for MAP1LC3, runs through the entire autophagy process and is currently recognized as an autophagy marker. LC3 expression in ex vivo skin tissue sections can be determined by immunofluorescence staining. If the expression is increased relative to the control group without adding active ingredients, it indicates that the composition can improve the autophagy ability of cells.

[0040] Specific test method: Normal human skin was obtained from breast plastic surgery. Punch biopsies of 6 mm in diameter were taken using a punch (pfm medical) and the skin tissue was kept in organotypic culture medium, at 37°C and 5% C02 in a humidified environment. The primary antibody used was rabbit polyclonal anti-LC 3 (1 :500; MBL) for 2 hours. The secondary antibody used was Alexa Fluor*488 donkey anti-rabbit antibody (1 :1000; Invitrogen) for 1 hour.

[0041] Method principle: The primary antibody is recognized using a fluorescently labeled secondary antibody. The fluorescent samples are then examined under a fluorescence microscope. DAPI counterstaining allows visualization of the nuclei and epidermal localization. The ex vivo skin tissue was treated twice a day for 48 hours with either PBS control or test samples from Table 2, in duplicate. Each treatment was applied as a 20 pl solution on top of the ex vivo skin tissue. The ex vivo skin tissue was prepared for preservation and sectioning by fixing the tissue in 10% formalin buffer for 4 hours. The samples were transferred to increasing concentrations of ethanol baths to remove water, followed by two xylene baths to remove ethanol and finally embedded in molten paraffin. The embedded skin biopsies were then cut into 4 pm thick sections using a microtome (Shandon) and placed on Superfrost Ultra Plus* slides (Thermo Scientific).

[0042] The sections were deparaffinated and rehydrated with successive baths of xylene, alcohol and water. Then, antigen retrieval was performed using a 600W microwave irradiation in citrate buffer 0.01 M pH 6 (Sigma) until boiling. After washing in PBS and saturation of non-specific sites with a 5% BSA (Sigma) solution for 30 minutes, the primary antibody was applied and the slides were incubated at room temperature in a humidified room with agitation. After washing the slides with PBS, the secondary antibody was applied in the dark at room temperature in a humidified room with agitation. Finally, the nuclei were stained with 4', 6-diamidino-2-phenylindole (DAPI, Molecular Probes*) at 0.3 uM for 5 minutes and the sections were mounted on Fluoro mount-G* (Electron Microscopy Sciences). The Axiovert 200M microscope was used to take the photographs.

[0043] Image quantification analysis was performed using Volocity image analysis software (Improvision) on three pictures for each condition. Fluorescence intensity was used to select representative areas. The result obtained was the sum of the green pixel intensity in the selected areas. Finally, for each picture, the sum obtained was adjusted by considering the area of the epidermis examined.

[0044] Statistical analysis Statistical analysis of the samples was performed using Student t test. P≤0.05 was significant, p≤0.01 was very significant, p≤0.005 was highly significant.

[0045] Table 2 Sample and test information

[0046] The results of the detection of the fluorescent expression of LC3 are shown in Figure 2 and Figure 3 .

[0047] From Figure 1 and Figure 2 , it can be seen that the whitening composition containing 0.005% tea freeze-dried powder and 0.5% lavender flower extract can synergistically increase the expression content of LC3 in the skin, effectively affect the process of autophagy in cells. Therefore, the whitening composition can achieve the effect of synergistically removing metabolic waste in the skin and improving the phagocytosis of melanin in cells, thereby achieving the effect of whitening.

[0048] (Three) Evaluation of the whitening effect of the whitening serum 1. Test sample: prepared according to the following formulation table; Table 3 Whitening serum formulation information

[0049] Preparation process: 1. Heat phase A to 80-85°C, dissolve completely; 2. Stir to cool to 40-45°C, mix phase B uniformly, and add to phase A.

[0050] Test population: healthy men and women aged 25-45 years old, with dark skin and no obvious difference between left and right faces; engaged in indoor work, without long-term or frequent exposure to ultraviolet light; no allergic diseases, no history of allergy to cosmetics and other external preparations; no history of photosensitivity, and no use of drugs affecting photosensitivity in the recent period; the skin of the test site should be free of birthmarks, inflammation, scars, and excessive hair; able to understand the test process and voluntarily participate in the test, a total of 10, with the control sample used on the left face and the example sample used on the right face.

[0051] Test instrument: German CK multifunctional skin tester; Test environment condition: test environment temperature 20-22℃, humidity 40-60%, and real-time dynamic monitoring is carried out; Product use method: usage amount: 0.3g / time / half face, once a day in the morning and evening, and the left and right faces are synchronously used with corresponding products; during the test period, the testers avoid excessive ultraviolet exposure, avoid using preparations containing whitening components, oral vitamin C as the main component, and preparations such as tranexamic acid, and in addition, the testers avoid using skin care cosmetics other than the test sample during the test period; Test site: the whole face.

[0052] Test process: (1) Instrument test: Germany CK multifunctional skin tester: Lab color model is composed of brightness (L) and three elements related to color a, b. L represents luminosity, a represents the range from magenta to green, and b represents the range from yellow to blue. The value range of L is from 0 to 100, and when L=50, it is equivalent to 50% black; the value range of a and b is from +127 to -128, in which +127a is magenta, and gradually transitions to -128a, which becomes green; similarly, +127b is yellow, and -128b is blue. All colors are composed of the three values, and the L* measured by the color instrument represents brightness, and the change represents the change of skin black and white degree, and the greater the value, the more the color is biased to white; a* represents red-green degree, and the change represents the change of red-green degree before and after using the whitening product; b* represents blue-yellow degree, and the change represents the change of skin blue-yellow degree before and after using the whitening product, and the L*, a* and b* values of color brightness, ITA degree are used as indexes in this application, and the greater the ITA value, the brighter the skin, and vice versa, the darker the skin.

[0053] Test result calculation and analysis: (1) Data arrangement method: the output data is the average value of 10 people in each group; (2) Select the corresponding area and select 5 points for analysis, including the forehead, both sides of the cheek, and both sides of the cheek, and finally arrange the average value to obtain the data of the whole face, and obtain the L, a, b value, chroma c*, and corrected L* value, and after conversion by the following formula, the whiteness ITA° is obtained.

[0054] ITA°=(Arc(L*-50) / b)×180 / π L*=-1.05×(c*-24)···R=1.000 (3) The test effect is as follows: Table 4 Whitening effect of whitening serum

[0055] miR-137 ID001129 RNU 44 as endogenous control ID001094 Principle Real-time PCR Cell preparation Cells were seeded in 6-well plates (Falcon). Cells were treated with different samples, diluted directly in culture medium, single treatment, for 6 hours.

[0056] Test method After treatment with mirVana* miRNA isolation kit (Ambion) to extract total RNA (including miRNA), remove culture medium, rinse cells with cold PBS, recover with lysis buffer. Purify RNA, which is eluted in RNase-free water. Then, perform reverse transcription of total RNA with high capacity cDNA reverse transcription kit (Thermo Fisher Scientific) containing RNase inhibitor. Perform real-time qPCR on StepOnePlus* thermocycler (Applied Biosystems) with TaqMan* Gene Expression Master Mix (Thermo Fisher Scientific) and TaqMan* Gene Expression Assays (Thermo Fisher Scientific). Taqman* Gene Expression Master Mix contains DNA polymerase, dNTPs, UDG (DNA-free), ROX* (passive fluorescence reference) and buffer. RNU44 TaqMan* Gene Expression Assay as endogenous control. In addition, replace DNA with water as negative control. Analyze three times per case.

[0057] After checking that the endogenous control level is stable, perform relative quantification of target expression with comparative Ct method (Livak K, and Schmittgen T. D., 2001) and data processing with StepOne* software (Applied Biosystems).

[0058] Conclusion: Compared with the control group, the expression of miR-137 in melanocytes after administration of tea freeze-dried powder was 98.4%, the expression of miR-137 in melanocytes after administration of lavender flower extract was 121.9%, and the expression of miR-137 in melanocytes after administration of the composition of tea freeze-dried powder and lavender flower extract was as high as 152.3%, significantly increasing the content of miR-137 in melanocytes, further proving that the composition can synergistically inhibit the synthesis of melanin.

[0059] The above description of the embodiments is only used to help understand the method of the present application and its core idea. It should be noted that, for those skilled in the art, without departing from the principles of the present application, some improvements and modifications can be made to the present application, and these improvements and modifications also fall within the protection scope of the claims of the present application.

Claims

1. A whitening composition, characterized by, The whitening composition comprises the following components: Camelia Sinensis leaf extract, lavender flower extract; wherein the Camelia Sinensis leaf extract content is 0.35-0.65% by mass, the lavender flower extract content is 35-65%, and deionized water makes up 100%.

2. The whitening composition of claim 1, wherein The Camelia Sinensis leaf extract content is 0.45-0.55%, and the lavender flower extract content is 45-55%.

3. The whitening composition of claim 1, wherein The Camelia Sinensis leaf extract is a Camelia Sinensis freeze-dried powder, and the preparation method of the Camelia Sinensis freeze-dried powder comprises the following steps: 1) Extraction: After the Camelia Sinensis leaves are crushed, a solvent is added, and after heating, ultrasonic extraction is performed, and the obtained crude filtrate is centrifuged at 8000-12000 rpm to obtain a crude extract; 2) Filtration and concentration: the crude extract is filtered through a 0.4um-0.6um ceramic membrane, further filtered through a 0.01-1um ultrafiltration unit to remove macromolecules above 200,000 daltons, and then concentrated through a reverse osmosis unit with a pressure of 2-5 MPa to obtain a small molecule Camelia Sinensis extract liquid concentrated by 8-10 times; 3) Freeze-drying process: the small molecule Camelia Sinensis extract liquid is pre-frozen at -50 to -40℃ and vacuum frozen to obtain the Camelia Sinensis freeze-dried powder.

4. The whitening composition of claim 3, wherein in step 1), the solvent used is deionized water or glacial water, the solvent-to-liquid ratio is 1:5-20, and the heating temperature is 85-95℃; in step 3), the pre-freezing comprises the following steps: pre-freezing at -50 to -40℃ for 0.5-2h; the vacuum freezing comprises the following steps: drying at -35 to -25℃ for 1-6h, drying at -25 to -15℃ for 1-6h, drying at -15 to -5℃ for 1-6h, drying at -5 to 5℃ for 1-6h, drying at 5 to 15℃ for 1-6h, drying at 15 to 35℃ for 1-6h, drying at 35 to 45℃ for 1-6h, drying at 145 to 55℃ for 1-6h, and drying at 55 to 65℃ for 1-6h; the vacuum degree of the drying chamber during drying is 66-300Pa.

5. The whitening composition according to claim 1, characterized in that, The preparation method of the lavender flower extract comprises the following steps: a) Pre-drying the narrow-leaved lavender flowers and flower stems; b) Grinding the pre-dried material obtained in step a) to a particle size range of 500μm-1mm, adding water and sodium hydroxide to adjust the pH to 10.8, and adding 2g / L or 3mM of phytic acid to obtain a mixture; c) Heating the mixture obtained in step b) at 80℃ with stirring to obtain a crude extract; d) Adding diatomite to the crude extract obtained in step c), filtering, adjusting the pH to 7.5 using an HCl solution, sequentially filtering on a filter with gradually decreasing porosity, then adjusting the pH to 6.3 using an HCl solution, and obtaining an aqueous extract with a dry weight of 12.6g / kg.

6. The method of preparing a whitening composition according to any one of claims 1 to 5, wherein comprises the following steps: The tea (Camelia Sinensis) leaf extract and the lavender flower extract are added to deionized water, dissolved and mixed uniformly to obtain the product.

7. Use of the whitening composition according to any one of claims 1 to 5 for the preparation of a skin external agent.

8. Use according to claim 7, wherein the compound is ###0002### The whitening composition is used as a whitening active ingredient, an active ingredient for improving autophagy, an active ingredient for inhibiting melanin production, and an active ingredient for improving melanin phagocytosis in keratinocytes in a skin external agent.

9. Use according to claim 7 or 8, characterised in that, The whitening composition is added in an amount of 0.01 wt% to 5 wt%, preferably 0.5 wt% to 1.5 wt%.

10. A skin external preparation having a whitening composition, characterized by, The external agent contains 0.5 wt% to 1.5 wt% of the composition according to claim 1.

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