Preparation method and application of tremella polysaccharide aqueous extract carbon dots
The preparation of carbon dots of Tremella polysaccharide water extract by hydrothermal method solved the problem of lack of functionality in the medical and health field, achieved significant effects of whitening, hydrating and anti-cancer, and was used in antithyroid cancer drugs and skin care products.
Patent Information
- Application Number
- CN202510604488.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-12
- Publication Date
- 2025-08-01
AI Technical Summary
The application of existing carbon dots in the medical and health field lacks functionality, and the method of combining traditional Chinese medicine with carbon materials to prepare functional carbon dots has not been fully explored.
Carbon dots of Tremella polysaccharide water extract are prepared by a simple one-step method of hydrothermal method. Carbon dots with low biotoxicity and whitening, antibacterial and anticancer effects are prepared. They are used in whitening and antithyroid cancer drugs and skin care products.
The carbon dots of Tremella polysaccharide water extract with low biotoxicity have achieved remarkable effects in whitening, hydrating, antibacterial and anticancer, and have broad application prospects.
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Figure CN120392816A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the field of carbon dots, and particularly relates to a preparation method and application of carbon dots of Tremella polysaccharide water extract. Background Art
[0002] Carbon dots (Cdots) are typically spherical structures and can be categorized as carbon quantum dots (CQDs) with a distinct lattice and carbon nanodots with or without a lattice. Numerous methods are currently available for preparing Cdots. Carbon source pyrolysis methods include laser ablation, acid pyrolysis, electrochemical pyrolysis, and arc discharge. Organic carbonization methods include calcination, hydrothermal methods, microwave methods, ultrasound methods, plasma treatment, and template methods. Compared to traditional fluorescent materials, fluorescent carbon materials have attracted considerable attention due to their low biotoxicity, excellent biocompatibility, physiological stability, and highly tunable fluorescence emission properties. In this work, numerous scientists have prepared numerous phototunable Cdots using small molecules such as citric acid, ethylenediamine, and o-phenylenediamine and have revealed their luminescence mechanisms. Their unique structural properties make them suitable carriers for various drug delivery methods, such as chemotherapy and anticancer drugs. However, the application of Cdots in healthcare is limited by their lack of functionality. Therefore, the preparation of functionalized Cdots is crucial and remains a critical challenge that needs to be addressed.
[0003] The combination of traditional Chinese medicine and carbon materials has gradually become one of the main methods for preparing functional carbon dots. By using the effective ingredients of traditional Chinese medicine as precursors to prepare carbon dots, it is expected that some new polymer compounds with improved original pharmacological activities or the development of activities that were not originally possessed will be obtained. This has become the main design theory of functional carbon dots derived from traditional Chinese medicine. Summary of the Invention
[0004] The present invention aims to provide a method for preparing and applying Tremella fuciformis (Terrillius) polysaccharide aqueous extract carbon dots. Using a simple one-step hydrothermal method, the present invention prepares Tremella fuciformis (Terrillius) polysaccharide aqueous extract carbon dots (Cdots), which have low biotoxicity, whitening and moisturizing, and antibacterial and anticancer effects. These Cdots are then used for skin whitening and anti-thyroid cancer treatments.
[0005] The present invention provides a preparation method and application of carbon dots of tremella polysaccharide water extract. The carbon dots of tremella polysaccharide water extract are used to prepare drugs against thyroid cancer, and the carbon dots of tremella polysaccharide water extract are used to prepare skin care products for whitening and moisturizing, or for repairing ultraviolet damage.
[0006] Furthermore, the mass concentration of the Tremella polysaccharide aqueous solution is 1-20 mg / mL.
[0007] Furthermore, the mass concentration of the carbon dots of the Tremella polysaccharide water extract is 5-15 mg / mL.
[0008] Furthermore, the mass concentration of the carbon dots of the Tremella polysaccharide water extract is 10 mg / mL.
[0009] Furthermore, the whitening includes reducing the melanin content in the skin.
[0010] The present invention discloses an application of carbon dots of a Tremella fuciformis polysaccharide water extract, wherein the carbon dots of the Tremella fuciformis polysaccharide water extract are used for preparing a skin care product for repairing ultraviolet damage.
[0011] The method for preparing carbon dots from a Tremella polysaccharide aqueous extract of the present invention is carried out according to the following steps:
[0012] The Tremella polysaccharide water extract is taken, water is added and mixed evenly to obtain a Tremella polysaccharide aqueous solution; the solution is transferred into a polytetrafluoroethylene reactor, reacted at a temperature of 120-300° C. for 5-12 hours, cooled, and filtered to obtain Tremella polysaccharide water extract carbon dots.
[0013] Furthermore, the filtration is performed using a 0.22 μm filter membrane.
[0014] Furthermore, the reaction temperature is 160° C. for 7 hours.
[0015] Furthermore, the preparation method of the Tremella polysaccharide water extract is as follows:
[0016] The method comprises the following steps: obtaining pest-free dried tremella, washing, removing impurities, crushing, and sieving to obtain tremella powder; adding water to dissolve the tremella powder, adding 20-100% ethanol by volume in a material-liquid ratio of 1:2-1:10 to extract the tremella powder; concentrating the tremella powder after extraction, and drying the tremella powder to obtain a tremella polysaccharide aqueous extract; wherein the extraction conditions are as follows: extracting the tremella powder 3-15 times at room temperature, with each extraction lasting 1-10 hours.
[0017] Furthermore, ethanol with a volume percentage of 20-100% is added for extraction at a material-liquid ratio of 1:5-1:8.
[0018] The present invention has the following beneficial effects:
[0019] The present invention uses a simple one-step hydrothermal method to prepare carbon dots derived from Tremella fuciformis polysaccharide water extract, which uses Tremella fuciformis polysaccharide water extract as a carbon source. These carbon dots have low biological toxicity, whiten and moisturize, reduce melanin, have antibacterial and anticancer effects, and can repair UV damage. The carbon dots have broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Figure 1 TEM image of carbon dots from Tremella fuciformis polysaccharide aqueous extract prepared in Example 1;
[0021] Figure 2 Particle size distribution of carbon dots from Tremella fuciformis polysaccharide aqueous extract;
[0022] Figure 3 Fluorescence spectra of Tremella fuciformis polysaccharide water extract at different excitation wavelengths;
[0023] Figure 4 UV-Vis absorption spectra of the water extract of Tremella polysaccharide and carbon dots of the water extract of Tremella polysaccharide; Figure A is the spectrum, and Figure B is the photo of the carbon dots of the water extract of Tremella polysaccharide under daylight lamp (left) and 365 nm UV lamp (right);
[0024] Figure 5 FT-IR spectrum of the carbon dots of the water extract of Tremella polysaccharide;
[0025] Figure 6 XPS survey spectrum of the carbon dots of the water extract of Tremella polysaccharide;
[0026] Figure 7 Effect of the carbon dots of the water extract of Tremella polysaccharide on the viability of B16F10 cells;
[0027] Figure 8 Cell viability of LO2 cells after incubation in carbon dots of the water extract of Tremella polysaccharide at different concentrations for 48 h (***, p < 0.001, **, p < 0.01, *, p < 0.05);
[0028] Figure 9 Cell viability of K1 cells after incubation in carbon dots of the water extract of Tremella polysaccharide at different concentrations for 48 h (***, p < 0.001, **, p < 0.01, *, p < 0.05);
[0029] Figure 10 Inhibitory zone diagram after culturing the carbon dots of the water extract of Tremella polysaccharide (1 mg / mL) with Escherichia coli;
[0030] Figure 11 Tyrosinase inhibitory activity diagram; (compared with the blank group at 24 h, ***, p < 0.001, **, p < 0.01, *, p < 0.05, compared with the blank group at 48 h, , p < 0.001, ##, p < 0.01, #, p < 0.05);
[0031] Figure 12 Whitening diagram of the carbon dots of the water extract of Tremella polysaccharide; among them, the left figure is the TYR activity diagram, and the right figure is the melanin content diagram;
[0032] Figure 13 Msson-Fontana staining diagram of the carbon dots of the water extract of Tremella polysaccharide; among them, the left figure is the Msson-Fontana staining diagram; the right figure is the melanin content calculation diagram;
[0033] Figure 14 ROS diagram of the carbon dots of the water extract of Tremella polysaccharide; among them, the left figure is the ROS fluorescence photo diagram; the right figure is the ROS content calculation diagram;
[0034] Figure 15Effect diagram of Tremella polysaccharide aqueous extract carbon dots on skin barrier-related genes;
[0035] Figure 16 CT photos of the tumor growth of nude mice in the model group, cisplatin group and Tremella polysaccharide carbon dot group at different days (the 7th day, 14th day and 21st day). Specific implementation mode
[0036] To make the purposes, technical solutions and advantages of the embodiments of the present invention clearer and more understandable, the spirit of the content disclosed in the present invention will be described in detail below. After any person skilled in the relevant technical field understands the embodiments of the content of the present invention, they can make changes and modifications according to the technologies taught by the content of the present invention, and it does not deviate from the spirit and scope of the content of the present invention.
[0037] The illustrative embodiments of the present invention and their descriptions are used to explain the present invention, but do not limit the present invention.
[0038] Example 1
[0039] 1) Preparation of Tremella polysaccharide aqueous extract carbon dots
[0040] Precisely weigh 0.0300 - 0.0500 g of Tremella polysaccharide aqueous extract, add 10 mL of distilled water to dissolve it to a final concentration of 1 - 20 mg / mL, transfer it to a polytetrafluoroethylene reaction kettle, and heat and react at 160 °C for 7 h. After the reaction, take the reaction solution and filter it through a 0.22 μm filter membrane to obtain a light yellow Tremella polysaccharide aqueous extract carbon dot solution. And store it in a refrigerator at 4 °C.
[0041] In the following examples, the Tremella polysaccharide aqueous extract carbon dot solution with a concentration of 1 - 20 mg / mL prepared in this example is diluted and used.
[0042] The preparation method of the Tremella polysaccharide aqueous extract is as follows:
[0043] Take pest-free dried Tremella, wash, remove impurities, crush, and sieve to obtain Tremella powder; after dissolving in water, add ethanol with a volume percentage of 20 - 100% for extraction according to the ratio of solid to liquid of 1:2 - 1:10, concentrate and dry after extraction to obtain Tremella polysaccharide aqueous extract; among them, the extraction conditions are extraction at room temperature for 3 - 15 times, and each extraction is for 1 - 10 hours.
[0044] Characterization of the Tremella polysaccharide aqueous extract carbon dots in this example
[0045] The prepared Tremella polysaccharide aqueous extract carbon dots have a particle size concentrated in 2 - 3 nm, with a uniform size distribution (as Figure 1-2 shown), and have obvious excitation-dependent characteristics. The optimal excitation wavelength is at 370 nm, and the optimal emission wavelength is about 448 nm (as Figure 3As shown). The obtained carbon dots from the water extract of Tremella polysaccharide were a pale yellow liquid under daylight and emitted blue-green fluorescence under a 365 nm ultraviolet lamp. In addition, the ultraviolet-visible absorption spectrum showed that both the water extract of Tremella polysaccharide and its carbon dot solution had an absorption peak at 220 nm, which was caused by π_π* transition, and there was another strong absorption peak at 280 nm in the carbon dot solution, which was caused by n-π* transition, indicating that there might be many unsaturated groups in the structure (such as Figure 4 As shown). Infrared spectrum identification showed that the carbon dots had strong absorption peaks at 3380 cm -1 , 2900 cm -1 , 1615 cm -1 , 1516 cm -1 , 1073 cm -1 respectively, which were attributed to the absorptions of O-H, C-H, C=O, C=C, and C-O groups (such as Figure 5 As shown). As Figure 6 , high-resolution X-ray photoelectron spectroscopy full-spectrum analysis showed two main absorption peaks of C and O in the carbon dots of the water extract of Tremella polysaccharide.
[0046] 2) Cell culture: The cells used in the experiment were from the American Type Culture Collection (ATCC, Manassas, VA, US). Human normal liver cells (LO2) and human thyroid cancer cells (K1) were cultured in RPMI 1640 medium in an incubator at 37 °C and 5% CO2.
[0047] 3) Bacterial culture: Escherichia coli (E. coli, ATCC25922) was transferred from LB solid medium to LB liquid medium and cultured at 37 °C and 200 rpm for 8 h to reach the logarithmic growth phase.
[0048] Example 2
[0049] 1) Study the cell viability and proliferation toxicity of the carbon dots from the water extract of Tremella polysaccharide by the CCK-8 method
[0050] Taking LO2 cells as an example, LO2 cells in the logarithmic growth phase were seeded into 96-well plates at 4000 cells per well and cultured for 12 h. After incubation, the carbon dots from the water extract of Tremella polysaccharide with a final concentration of 1 - 20 mg / mL in Example 1 were co-incubated with LO2 cells at 0 μg / mL, 50 μg / mL, 100 μg / mL, 150 μg / mL, and 200 μg / mL at 200 μL per well for 48 h. After incubation, 100 μL of the culture medium was aspirated, and then 10 μL of CCK-8 was added to each well according to the instructions and incubated in a cell culture incubator for 45 min -2·h. After the incubation, measure the absorbance at 450 nm using a microplate reader and calculate the cell viability based on the absorbance.
[0051] The results of the effect of Tremella polysaccharide-CD (carbon dots extracted from the water extract of Tremella polysaccharide) on the viability of B16F10 cells showed that compared with the blank group, Tremella polysaccharide carbon dots (effective concentrations were 12.5, 25, 50, 100 μg / mL) had no significant effect on the viability of B16F10 cells, while 200 μg / mL had a significant effect on the viability of B16F10 cells (as Figure 7 shown).
[0052] The results of the in vitro cytotoxicity of the carbon dots extracted from the water extract of Tremella polysaccharide showed that the carbon dots extracted from the water extract of Tremella polysaccharide still had good biocompatibility with LO2 cells at an effective concentration of 200 μg / mL (as Figure 8 shown). And at the same concentration, the carbon dots extracted from the water extract of Tremella polysaccharide had an obvious inhibitory effect on the proliferation of human thyroid cancer cell K1 (as Figure 9 shown). This suggests that the carbon dots extracted from the water extract of Tremella polysaccharide are very likely to become potential drugs for the treatment of thyroid cancer and have broad application prospects.
[0053] 2) Evaluate the antibacterial ability of the carbon dots extracted from the water extract of Tremella polysaccharide through the antibacterial circle experiment
[0054] Soak blank drug sensitivity test paper with a diameter of 6 mm in the carbon dot solution overnight. Then spread Escherichia coli on the LB solid medium. Place each soaked drug sensitivity test paper in the middle of the agar plate and incubate it with Escherichia coli. The culture conditions are: incubate overnight in a constant temperature and humidity incubator at 37 °C. After 24 h, take a photo and record the diameter of the antibacterial circle.
[0055] The results of the antibacterial circle experiment of the carbon dots extracted from the water extract of Tremella polysaccharide in this example showed that the carbon dots extracted from the water extract of Tremella polysaccharide had a significant inhibitory effect on Escherichia coli. The diameter of the antibacterial circle could reach 1.18 ± 0.05 cm, as Figure 10 shown. This provides strong evidence for its antibacterial performance.
[0056] 3) Examine the effect of the carbon dot solution of the water extract of Tremella polysaccharide on tyrosinase activity by the L-DOPA method
[0057] Take B16F10 melanoma cells in the logarithmic growth phase and adjust the cell concentration to 4×10 3 / mL, inoculate 100 μL per well into a 96-well cell culture plate. After culturing for 24 hours, add 200 μL of drug-containing culture medium at different concentrations per well successively. After culturing for 24 and 48 hours respectively, discard the culture medium, wash twice with PBS. Add 50 μL of 1% TrionX-100 to each well, quickly freeze at -80 °C for 30 min, thaw at room temperature to lyse the cells, add 10 μL of 0.25% dopa solution after pre-warming at 37 °C, react in a 37 °C water bath for 2 h, and detect the specific absorbance A475 of the reaction product with an enzyme-linked immunosorbent assay instrument. Calculate the inhibition rate of tyrosinase activity.
[0058] The measurement results (as Figure 11 shown) indicate that compared with the blank control group, the carbon dots of the water extract of Tremella polysaccharide have a significant inhibitory effect on the production of tyrosinase, and with the increase of the concentration and time of the carbon dots, its inhibitory effect on tyrosinase shows concentration and time dependence, indicating that the carbon dots of the water extract of Tremella polysaccharide have the effect of reducing melanin production.
[0059] Example 3
[0060] 1) Evaluation of the water replenishing effect of the carbon dots of the water extract of Tremella polysaccharide
[0061] Evaluate the water replenishing effect of the carbon dots of the water extract of Tremella polysaccharide in Example 1. The experimental subjects are 10 volunteers with the same skin condition score, divided into groups of 5. The volunteers wash their faces with normal clean water every day and use a facial mask once every two days. The specific operation is to take a compressed facial mask after washing the face with clean water, soak it in 10 mL of carbon dot solution or distilled water and apply it on the face for 15 min, and score according to the following criteria: dry +, not dry ++, relatively moist ++, moist +++.
[0062] As shown in Table 1, compared with the control group, after applying the carbon dot solution on the face for 15 days, the skin conditions of the experimental group all improved significantly, while two volunteers in the control group still had a dry skin condition. After using it for 21 days, although the control group had all achieved the water replenishing effect, the skin conditions of the 5 volunteers in the experimental group had all reached the moist state. The experimental results show that the carbon dot solution of the water extract of Tremella polysaccharide does have a water replenishing effect and has a good use effect.
[0063] Table 1 Statistical table of volunteers' skin conditions
[0064]
[0065]
[0066] 2) Whitening research on the carbon dots of the water extract of Tremella polysaccharide
[0067] (1) Extraction of total protein from B16F10 cells
[0068] B16F10 cells in the logarithmic growth phase with a cell density of 8.00×10 4 cells / mL were seeded in 6-well plates. After 24 h of culture, the culture medium was removed and replaced with a medium containing a-MSH (0.3 μM) for 48 h. The medium was removed, and the cells were washed twice with PBS. The cells were collected, 50 μL of cell lysate was added, and the cells were lysed at 4 °C for 1 h. The lysate was collected by centrifugation at 12,000 rpm for 20 min, and the protein concentration was detected by the BCA method.
[0069] (2) Detection of TYR activity in B16F10 cells
[0070] TYR activity was detected by the dopa oxidation method. Cell protein lysate (total protein of 80.00 μg), 80 μL, and 5.00 mM L-dopa (L-DOPA) were added to a 96-well plate, and PB buffer (0.01 M) was added to make up to 200 μL. The mixture was incubated at 37 °C for 30 min, and the absorbance at 492 nm was detected using a microplate reader.
[0071] (3) Detection of melanin content in B16F10 cells
[0072] The melanin content in B16F10 cells was detected by the alkaline lysis method. The precipitate after centrifugation of the above cell lysate was added with 50 μL of 1.00 mol / L NaOH (containing 10.00% DMSO), heated in a metal bath at 80 °C for 1 h, and the absorbance at 405 nm was detected using a microplate reader, and normalized using the corresponding protein concentration.
[0073] The results of TYR activity and melanin of the carbon dots from the water extract of Tremella fuciformis polysaccharide showed (as Figure 12 shown) that compared with the model group, Arbutin (125 μg / mL) could inhibit the TYR activity in B16F10 cells and significantly reduce the melanin content. The carbon dots from the water extract of Tremella fuciformis polysaccharide (effective concentrations of 25, 50, and 100 μg / mL) could inhibit the TYR activity in B16F10 cells, significantly reduce the melanin content, and showed a concentration dependence.
[0074] (4) Msson-Fontana staining
[0075] ① Fixation: 10% neutral formalin is the best fixative, and fixatives such as chromate and mercuric oxide should be avoided.
[0076] ② Sectioning: All types of sections can be processed, and resin sections may require some adjustments.
[0077] ③ Place the experimental sections and control sections in distilled water.
[0078] ④ Add Fontana silver ammonia solution and stain in the dark for 12 - 24 h or incubate in an incubator at 56 °C for 30 - 40 min.
[0079] ⑤ Wash thoroughly with distilled water for 5 - 6 times.
[0080] ⑥ Treat the sections with hypo solution for 1 - 5 min.
[0081] ⑦ Treat with tap water for 3 - 5 min.
[0082] ⑧ (Optional) Add neutral red staining solution and gently counterstain for 5 min.
[0083] ⑨ Rinse with distilled water and dehydrate with 10.95% ethanol and absolute ethanol.
[0084] ⑩ Clear with xylene and mount with neutral balsam.
[0085] The Msson - Fontana staining results of carbon dots from the water - extracted polysaccharide of Tremella fuciformis showed (as Figure 13 shown) that compared with the model group, arbutin (125 μg / mL) could significantly reduce the melanin content in B16F10 cells, and carbon dots from the water - extracted polysaccharide of Tremella fuciformis (effective concentrations were 25, 50, 100 μg / mL) could significantly reduce the melanin content in B16F10 cells, showing a concentration - dependent effect.
[0086] (5) Investigation of ROS (reactive oxygen species) induced by ultraviolet damage
[0087] Dilute CM - H2DCFDA with serum - free culture medium at a ratio of 1:1000 to make the final concentration 5 μM. Remove the cell culture medium, add an appropriate volume of the diluted CM - H2DCFDA. The added volume should be sufficient to cover the cells. Usually, for one well of a six - well plate, add no less than 1 mL of the diluted CM - H2DCFDA. Incubate in a cell culture incubator at 37 °C for 30 minutes. Wash the cells three times with serum - free cell culture medium to fully remove the CM - H2DCFDA that has not entered the cells. Usually, the positive control of reactive oxygen species can significantly increase the level of reactive oxygen species 20 - 30 minutes after stimulating the cells, and then detect with a flow cytometer.
[0088] The results showed that compared with the model group, carbon dots from the water - extracted polysaccharide of Tremella fuciformis (effective concentrations were 25, 50, 100 μg / mL) could inhibit the accumulation of ROS in HaCaT cells induced by ultraviolet damage (as Figure 14 shown).
[0089] (6) Investigation of skin genes induced by ultraviolet damage
[0090] Total RNA was extracted from HaCaT cells using the NucleoZOL kit (machinery-negel, 740404). Complementary DNA (cDNA) was prepared from 1 μg of total rNA using a reverse transcription kit (intron, 25087), and PCR analysis was performed to determine the levels of each transcript, FLG, AqP3, and INU-1 proteins. Reverse transcription was carried out at 95 °C for 3 min, followed by 25 - 30 cycles of PCR at 94 °C for 30 s (denaturation), 50 - 60 °C for 1 min (annealing), and 72 °C for 1 min (extension). The amplified transcripts were separated on an agarose gel by electrophoresis and visualized by staining with EcoDye (Biofact, ES301).
[0091] The results showed that compared with the model group, retinoic acid (10 μM) could promote the expression of FLG, AqP3, and INU-1 genes in HaCaT cells induced by ultraviolet damage, and the aqueous extract carbon dots of Tremella polysaccharide (the effective concentrations were 25, 50, and 100 μg / mL) could promote the expression of FLG, AqP3, and INU-1 in HaCaT cells induced by ultraviolet damage (as Figure 15 shown).
[0092] Example 4
[0093] Evaluation of the in vivo anti-cancer activity effect of the aqueous extract carbon dots of Tremella polysaccharide
[0094] Nine male nude mice, 4 - 6 weeks old and weighing about 15 g, were selected. The concentration of K1 cells in the logarithmic growth phase was adjusted to 3×10 6 / 200 μL, and tumors were inoculated subcutaneously into the axilla of nude mice at 200 μL / animal. After successful tumor modeling, the cisplatin group was intraperitoneally injected with the drug at 5 mg / kg for two consecutive days, the Tremella polysaccharide carbon dot group was intragastrically administered at 5 mg / kg once a day, and the model group was intragastrically given an equal volume of normal saline once a day for three consecutive weeks. CT scans of the tumor sites were taken on the 7th, 14th, and 21st days, respectively.
[0095] As Figure 16 shown, 21 days after drug administration, the CT images showed that the tumor volume in the Tremella polysaccharide carbon dot group was significantly smaller than that in the model group and the cisplatin treatment group, showing good anti-tumor effects. This indicates that in addition to excellent moisturizing, whitening, and antibacterial activities, the Tremella polysaccharide carbon dots also have potential anti-tumor ability.
Claims
1. Application of carbon dots prepared from water extract of tremella polysaccharide, characterized in that The carbon dots of the water extract of Tremella polysaccharide are used for preparing drugs for anti-thyroid cancer, and the carbon dots of the water extract of Tremella polysaccharide are used for preparing skin-whitening and moisturizing skin care products or skin care products for repairing ultraviolet damage.
2. Use of a carbon dot prepared from a water extract of tremella polysaccharide according to claim 1, characterized in that The mass concentration of the carbon dots of the water extract of Tremella polysaccharide is 1-20 mg / mL.
3. Use of a carbon dot prepared from a water extract of tremella polysaccharide according to claim 2, characterized in that The mass concentration of the carbon dots of the water extract of Tremella polysaccharide is 5-15 mg / mL.
4. Use of a carbon dot prepared from a water extract of tremella polysaccharide according to claim 3, characterized in that The mass concentration of the carbon dots of the water extract of Tremella polysaccharide is 10 mg / mL.
5. Use of a carbon dot prepared from a water extract of tremella polysaccharide according to claim 1, characterized in that The skin whitening includes reducing the content of skin melanin.
6. The preparation method of tremella polysaccharide water extract carbon dots according to any one of claims 1 to 5, characterized in that It is carried out according to the following steps: Take the water extract of Tremella polysaccharide, add water and mix evenly to obtain an aqueous solution of Tremella polysaccharide; transfer it into a polytetrafluoroethylene reaction kettle, react at a temperature of 120-300 °C for 5-12 h, cool, and filter to obtain the carbon dots of the water extract of Tremella polysaccharide.
7. The preparation method of tremella polysaccharide water extract carbon dots according to claim 6, characterized in that The filtration is carried out using a 0.22 μm filter membrane.
8. A method for preparing tremella polysaccharide aqueous extract carbon dots according to claim 6, characterized in that React at a temperature of 160 °C for 7 h.
9. The preparation method of tremella polysaccharide aqueous extract carbon dots according to claim 6, characterized in that The preparation method of the water extract of Tremella polysaccharide is as follows: Take pest-free dried Tremella, wash, remove impurities, crush, and sieve to obtain Tremella powder; dissolve it in water, and add ethanol with a volume percentage content of 20-100% for extraction according to a solid-liquid ratio of 1:2-1:
10. After extraction, concentrate and dry to obtain the water extract of Tremella polysaccharide; among them, the extraction conditions are extraction at room temperature for 3-15 times, and each extraction is 1-10 h.
10. The preparation method of tremella polysaccharide water extract carbon dots according to claim 9, characterized in that Add ethanol with a volume percentage content of 20-100% for extraction according to a solid-liquid ratio of 1:5-1:8.