A method for preparing a skin care composition containing kiwi juice and use thereof

Abstract

The present application relates to the daily chemical technical field, especially to a preparation method and application of a skin care composition containing kiwi juice, comprising the following steps: (1) providing kiwi raw materials, black rice bran raw materials and sea buckthorn seed meal raw materials, respectively pretreating to obtain kiwi treatment, black rice bran treatment and sea buckthorn seed meal treatment; (2) mixing the kiwi treatment, black rice bran treatment and sea buckthorn seed meal treatment obtained in step (1) and performing enzymatic hydrolysis treatment; (3) performing lactic acid bacteria fermentation on the enzymatic hydrolysis product obtained in step (2); (4) performing yeast fermentation after lactic acid bacteria fermentation to obtain the composition. After phenolic acid release, peptide preparation treatment and continuous fermentation treatment, the obtained system not only does not appear significant stability decline, but also can simultaneously obtain higher antioxidant capacity, better skin color improvement effect, lower irritation and better skin feeling performance, which embodies obvious comprehensive technical effect different from the prior art.

Description

Technical Field

[0001] This invention relates to the field of daily chemical technology, and in particular to a method for preparing a skin care composition containing kiwi juice and its application. Background Technology

[0002] The use of naturally derived active ingredients in whitening, brightening, antioxidant, and barrier-repairing cosmetics is increasing. Kiwi fruit contains vitamin C, polyphenols, flavonoids, organic acids, pectin, and superoxide dismutase, which have potential applications in improving dull skin tone, reducing oxidative damage, and enhancing skin radiance. However, there are still several limitations to the direct use of kiwi fruit as a cosmetic ingredient.

[0003] First, kiwifruit contains highly active proteases. While these proteases have value in the food digestive system, they may overact on keratin in topical skin applications, leading to stinging, redness, tightness, or barrier discomfort. Especially when kiwifruit juice is added directly to serums, lotions, or masks without desensitization treatment, the coexistence of active proteases and fruit acids can amplify skin irritation, making it difficult to stably use in cosmetics with high concentrations of these proteases.

[0004] Secondly, kiwifruit cell walls contain structural components such as pectin, cellulose, and hemicellulose. Ordinary pressing or water extraction is insufficient to fully release the flavonoids, polyphenols, and vitamin C within the cells, while excessive crushing can easily lead to the combined action of polyphenol oxidase, metal ions, and oxygen, causing browning, off-flavors, and loss of activity. Therefore, there is a contradiction between the release efficiency and stable maintenance of kiwifruit's active ingredients: insufficient extraction results in low levels of effective substances, while excessive extraction exacerbates oxidation reactions.

[0005] Secondly, kiwifruit is a high-sugar fruit, and its juice contains fermentable sugars such as glucose and fructose. These sugars contribute to the sticky feel on the skin and also easily become a nutrient source for microbial growth and gas production during storage. Even with conventional preservation systems, high-sugar plant juices still pose risks of darkening in color, changing odor, rancidity, gas production, or abnormal viscosity during long-term storage, high-temperature transportation, or repeated opening and closing.

[0006] Existing technologies often employ enzymatic hydrolysis, sterilization, fermentation, or filtration to improve the stability of plant juices. However, conventional kiwifruit fermentation broth primarily focuses on the conversion of sugars in the juice into organic acids, typically remaining at the level of "plant juice fermentation products." While this type of technology can reduce some sugar content and produce certain organic acids, it struggles to simultaneously address the following issues: firstly, kiwifruit polyphenols and vitamin C are easily oxidized; secondly, kiwifruit protease may cause skin irritation; thirdly, the antioxidant, whitening, repairing, and skin-improving effects of single kiwifruit fermentation products are relatively limited; and fourthly, when acidic fermentation products are combined with whitening active ingredients such as niacinamide, compatibility issues arise regarding pH, color, odor, and activity stability.

[0007] Furthermore, plant-based compound fermentation cannot simply achieve stable and significant synergistic effects by adding more plant species. If the selected plants only share similar vitamin or polyphenol sources with kiwifruit, their technological contribution is likely to appear as an additive effect of conventional whitening plants, making it difficult to demonstrate a clear chemical transformation relationship and unpredictable results. Therefore, a new technological solution is still needed that allows kiwifruit-derived polyphenols and organic acids to not only be released but also coexist with phenolic acids, active peptides, and post-generative polysaccharides from other sources in a stable system, thereby simultaneously improving whitening and brightening, anti-oxidation, barrier repair, irritation reduction, and skin feel. Summary of the Invention

[0008] This invention provides a method for preparing a skincare composition containing kiwifruit juice, the composition obtained by this method, and a cosmetic composition containing the composition. This technical solution does not involve simple fermentation of kiwifruit juice, nor does it involve a common mixture of multiple plant extracts. Instead, it uses kiwifruit, black rice bran, and sea buckthorn seed meal as three complementary substrates. Through cell wall disruption, phenolic acid release, peptide preparation, enzymatic hydrolysis, lactic acid bacteria fermentation, and yeast fermentation, polyphenols from kiwifruit, phenolic acids from black rice bran, active peptides from sea buckthorn seed meal, organic acids produced during fermentation, and polysaccharides from yeast coexist in the same metabiotic system.

[0009] In this invention, kiwifruit primarily provides vitamins, polyphenols, flavonoids, pectin, and organic acid precursors. Through cell wall disruption and enzymatic hydrolysis, the release of active substances within kiwifruit cells is enhanced, while some pectinous substances are converted into lower molecular weight pectin degradation products. Compared to untreated kiwifruit juice, this treatment method reduces the heaviness and stickiness caused by large-molecule pectin and improves the bioavailability of flavonoids and polyphenols.

[0010] In this invention, black rice bran is not used as a common grain powder or pigment source, but rather as a source of bound phenolic acids. Some phenolic acids in black rice bran, such as ferulic acid, p-coumaric acid, and caffeic acid, are usually bound to cell wall polysaccharides, lignin, or arabinoxylan structures, making them difficult to fully release through ordinary water extraction. This invention uses a phenolic acid release treatment to convert the bound phenolic acids into free or usable forms that are more readily involved in antioxidant and skin conditioning effects. This step expands the role of black rice bran beyond simply providing plant powder or color; it provides the system with phenolic acid components with a clearly defined chemical origin and transformation pathway.

[0011] In this invention, sea buckthorn seed meal is not used as a regular sea buckthorn extract, but rather as a source of plant protein and polyphenol residues. After peptide processing, the proteins in the sea buckthorn seed meal are hydrolyzed into smaller molecular weight active peptides. These active peptides can improve skin nourishment and barrier repair, and can form hydrogen bonds, hydrophobic interactions, or weak complexations with polyphenols, phenolic acids, and polysaccharides, thereby improving the dispersion stability of active ingredients in the system. Compared to directly adding sea buckthorn oil or sea buckthorn fruit extract, peptide processing of sea buckthorn seed meal can better reduce greasiness and color burden, and improve the resource utilization value of by-products.

[0012] This invention employs a continuous processing method involving lactic acid bacteria fermentation and yeast fermentation. Lactic acid bacteria fermentation converts some sugars in kiwifruit and other substrates into organic acids such as lactic acid, thereby reducing residual sugar content and mitigating the stickiness and microbial risks associated with high-sugar systems. Yeast fermentation further produces amino acids, nucleotides, glutathione, and yeast-derived polysaccharides, and provides post-biotic components such as β-glucan and mannan during subsequent processing. Through the continuous action of these two types of microorganisms, the resulting composition is no longer a single fruit juice fermentation broth, but a complex active system containing phenolic acids, polyphenols, organic acids, active peptides, and post-biotic polysaccharides.

[0013] A key technical feature of this invention is that it does not rely on a single whitening active ingredient as the source of efficacy, but rather allows different chemical categories of active ingredients to perform different functions. Kiwi-derived polyphenols and black rice bran-derived phenolic acids reduce oxidation and improve dull skin tone; fermented organic acids gently promote keratin metabolism and enhance skin radiance; sea buckthorn seed meal-derived active peptides improve skin nourishment and repair; and yeast-derived polysaccharides reduce irritation from topical applications and improve skin barrier comfort. These components form a stable symbiotic relationship within the same fermentation system, giving the resulting composition a more complete source of efficacy than kiwi fermentation alone.

[0014] Another important technical feature of this invention is that the above composition is further used in whitening, brightening, and repairing cosmetic formulations, and is compounded with niacinamide, β-glucan, panthenol, betaine, inositol, phytate, trehalose, and an amino acid buffer system. Niacinamide inhibits the transport of melanin to keratinocytes; the polyphenols, phenolic acids, and organic acids in the composition reduce oxidative dullness and improve skin tone evenness; β-glucan and panthenol improve skin barrier function; betaine and inositol reduce the tightness caused by acidic active ingredients and improve moisturizing comfort; and the phytate, trehalose, and amino acid buffer system improves the storage stability of polyphenols, phenolic acids, active peptides, and niacinamide in the same formulation.

[0015] Specifically, this invention notes that when fermentation products containing organic acids are combined with niacinamide, if the system pH is too low, it may affect the long-term stability of niacinamide and increase skin irritation; if the pH is too high, polyphenols, phenolic acids, and anthocyanins are more prone to oxidation and discoloration, and the brightening effect of organic acids is weakened. Therefore, this invention uses amino acid buffers and weak acid salts to jointly regulate the system, achieving a balance between acidic fermentation actives, niacinamide, and skin mildness. This approach differs from simply adjusting the pH; it simultaneously considers the compatibility between whitening activity, antioxidant stability, and skin tolerance.

[0016] This invention also notes that plant ferments often result in a sticky, heavy, or unpleasant aftertaste. To address this issue, this invention introduces betaine, inositol, polyol moisturizers, polyglutamic acid, or hyaluronic acid-based moisturizing ingredients into cosmetic compositions, and may further incorporate small amounts of isododecane and siloxane-based skin feel modifiers. This formulation system allows for a balance between the hydrating feel and the smooth, spreadable texture provided by the ferments, reducing the stickiness that can occur when ferments, polysaccharides, and organic acids coexist, thereby improving the comfort of using serum-type products.

[0017] The technical solution of this invention has certain unexpected technical effects. The combination of kiwifruit, black rice bran, and sea buckthorn seed meal may lead to darker color, more complex odor, increased system viscosity, and decreased storage stability, because kiwifruit is prone to browning, black rice bran contains anthocyanins and phenolic acids, and sea buckthorn seed meal contains protein and polyphenol residues. Direct mixing of the three can easily cause precipitation, discoloration, or off-odors. However, this invention, by first releasing the bound phenolic acids from the black rice bran, then preparing peptides from the sea buckthorn seed meal, and subsequently co-enzymatically hydrolyzing and continuously fermenting it with kiwifruit, allows the active ingredients from different sources to exist in a relatively stable small molecule or colloidal dispersion state. Simultaneously, the phytate, trehalose, and amino acid buffer system in subsequent cosmetic formulations reduces the impact of metal-catalyzed oxidation and pH fluctuations, thus enabling the highly active, multi-component plant fermentation system to maintain good color, odor, and skin feel stability.

[0018] The present invention also has the following beneficial effects: This invention uses kiwifruit as the main source of active ingredients. Through cell wall disruption and enzymatic hydrolysis, the pectin, cellulose, and hemicellulose structures in the kiwifruit cell walls are partially degraded, thereby promoting the release of intracellular vitamins, flavonoids, polyphenols, and organic acid precursors. Compared with traditional pressing or ordinary water extraction processes, this method can improve the release of active ingredients and reduce the loss of unreleased active substances with the fruit pomace.

[0019] Phenolic acids such as ferulic acid, p-coumaric acid, and caffeic acid in black rice bran typically exist in bound form within the cell wall structure, making them difficult to fully utilize using conventional extraction processes. This invention employs a phenolic acid release treatment to convert some bound phenolic acids into free or usable forms, thereby increasing the content and utilization efficiency of phenolic acids in the system. This treatment not only enhances the utilization value of the black rice bran raw material but also strengthens the antioxidant capacity and photodamage protection capabilities of the resulting composition.

[0020] This invention utilizes sea buckthorn seed meal as a protein source, converting large-molecule proteins into small-molecule active peptides through peptide processing. The resulting active peptides exhibit good skin affinity and permeability, and can participate in skin barrier repair and moisturizing. Simultaneously, this technical solution enhances the utilization value of sea buckthorn seed meal byproducts and reduces resource waste.

[0021] Kiwifruit is a high-sugar fruit, and traditional kiwifruit juice contains a large amount of residual glucose and fructose, which can easily lead to microbial contamination, fermentation gas production, and decreased storage stability. This invention utilizes lactic acid bacteria fermentation and yeast fermentation to convert some of the sugars into organic acids and fermentation metabolites, reducing the residual sugar content in the system and thus mitigating the microbial risks and sticky feel associated with high-sugar systems.

[0022] The key feature of this invention is that it does not obtain a single plant extract or a single plant fermentation broth, but rather allows polyphenols from kiwifruit, phenolic acids from black rice bran, active peptides from sea buckthorn seed meal, organic acids produced during fermentation, and polysaccharides from yeast to coexist in the same system.

[0023] Typically, the coexistence of polyphenols, phenolic acids, active peptides, and organic acids can easily lead to problems such as darkening of color, increased precipitation, or decreased activity. This invention discovers that after phenolic acid release treatment, peptide preparation treatment, and continuous fermentation treatment, active components from different sources can exist in a relatively stable dispersed state. Furthermore, by further incorporating phytates, trehalose, and a buffer system, the impact of metal ion-induced oxidation reactions and acid-base fluctuations on the stability of the active substances can be effectively reduced, thereby improving the storage stability of the system.

[0024] This invention further applies the co-fermented biogenic composition to a cosmetic system in conjunction with niacinamide. By introducing an amino acid buffering system and a stabilizing system, niacinamide can coexist for a long time with the fermentation system containing organic acids, polyphenols, and phenolic acids, thereby reducing the interaction between active ingredients and improving formulation stability and product applicability.

[0025] When plant ferments, polysaccharides, and organic acids are present together, products can easily become heavy, sticky, or leave a lingering residue. This invention further incorporates betaine, inositol, polyol moisturizers, and skin-feel-regulating components, resulting in a product that combines moisturizing, hydrating, and smooth spreadability. Compared to traditional plant ferment extracts, it improves user comfort while maintaining a high content of active ingredients.

[0026] Those skilled in the art generally believe that when kiwifruit, black rice bran, and sea buckthorn seed meal are present simultaneously, the high content of polyphenols, anthocyanins, proteins, and sugars can easily lead to unstable color, increased precipitation, and complex odors in the system. However, the system obtained by this invention, through phenolic acid release, peptide preparation, and continuous fermentation, not only does not show a significant decrease in stability, but also simultaneously achieves high antioxidant capacity, good skin tone improvement, low irritation, and superior skin feel, demonstrating a comprehensive technical effect that is significantly different from existing technologies. Detailed Implementation

[0027] The technical solution of the present invention will be described in detail below. It should be understood that the specific embodiments described below are used to illustrate the technical principles and possible implementation methods of the present invention, and are not intended to unreasonably limit the scope of protection of the present invention. Without departing from the technical concept of the present invention, those skilled in the art can make appropriate adjustments to the types of raw materials, processing order, ratio, temperature, time, strains of bacteria, or cosmetic dosage forms.

[0028] This invention provides a skincare composition containing kiwi juice and a cosmetic composition containing a skincare composition containing kiwi juice. The co-fermented biogenic composition uses kiwi, black rice bran, and sea buckthorn seed meal as main raw materials, and is obtained through kiwi cell wall breaking treatment, black rice bran phenolic acid release treatment, sea buckthorn seed meal peptide preparation treatment, mixed enzymatic hydrolysis, lactic acid bacteria fermentation, yeast fermentation, and post-treatment. The resulting composition simultaneously contains polyphenols from kiwi, phenolic acids from black rice bran, active peptides from sea buckthorn seed meal, organic acids produced during fermentation, and polysaccharides from yeast. Furthermore, by compounding this co-fermented biogenic composition with niacinamide, β-glucan, panthenol, betaine, inositol, phytate, trehalose, and an amino acid buffer system, a cosmetic composition with whitening and brightening, antioxidant, gentle keratin conditioning, barrier repair, moisturizing, and pleasant skin feel can be obtained.

[0029] Raw material selection for a skin care composition containing kiwi juice The kiwifruit raw material can be fresh kiwifruit, kiwifruit pulp, kiwifruit juice, frozen kiwifruit, kiwifruit pomace, or a combination thereof. Preferably, fresh kiwifruit with moderate ripeness, high soluble solids content, and no obvious softening or browning is used. In this invention, kiwifruit mainly provides vitamins, polyphenols, flavonoids, organic acid precursors, pectin substances, and some protease active ingredients. The polyphenols and flavonoids contained in kiwifruit can participate in antioxidant and skin tone improvement; its organic acid precursors can be converted into mild keratin conditioning ingredients after fermentation; and the pectin substances can improve the system's hydration and dispersion stability after degradation.

[0030] The black rice bran can be the bran layer, black rice germ, black rice bran, or a combination thereof obtained during black rice processing. Preferably, it is low-temperature dried black rice bran that has not undergone significant oxidative rancidity and has a high total phenolic content. Black rice bran contains ferulic acid, p-coumaric acid, caffeic acid, anthocyanins, and phytic acid components. Unlike ordinary plant extracts, some phenolic acids in black rice bran exist in a bound form within the cell wall structure, making them difficult to fully release through ordinary water extraction. This invention uses a phenolic acid release treatment to convert bound phenolic acids into usable phenolic acids, thereby improving the system's antioxidant capacity and photodamage protection capabilities.

[0031] The sea buckthorn seed meal can be defatted seed meal after sea buckthorn seed oil extraction, sea buckthorn seed powder, the portion of sea buckthorn pomace rich in seed protein, or a combination thereof. Defatted sea buckthorn seed meal is preferred. In this invention, sea buckthorn seed meal is not used as a common sea buckthorn extract or oil component, but rather as a source of plant protein and polyphenol residues. After peptide treatment, the large molecular proteins in the sea buckthorn seed meal are converted into small molecular active peptides. These active peptides can improve skin nourishment and repair, and, together with polyphenols, phenolic acids, and polysaccharides, enhance the dispersion stability of the system.

[0032] In a preferred embodiment, the mass ratio of kiwifruit, black rice bran, and sea buckthorn seed meal is 75–90:5–15:3–15, more preferably 80–85:8–12:5–10, and even more preferably 82:10:8. This ratio balances the brightening activity of kiwifruit, the phenolic acid-enhancing effect of black rice bran, and the peptide-repairing effect of sea buckthorn seed meal. If the proportion of kiwifruit is too low, the system will lack sufficient sources of fruit acid precursors and flavonoids; if the proportion of black rice bran is too high, it may introduce an excessively dark color and grain odor; if the proportion of sea buckthorn seed meal is too high, the burden of protein and suspended matter will increase, potentially affecting the clarity and skin feel of the post-processed product.

[0033] Cell wall breaking treatment of kiwi fruit raw materials Kiwi fruit raw materials are preferably subjected to an antioxidant pretreatment. The pretreatment may employ an aqueous solution containing ascorbic acid, citric acid, phytate, EDTA salt, or a combination thereof. Preferably, the pretreatment solution contains ascorbic acid, citric acid, sodium phytate, and disodium EDTA. Ascorbic acid reduces the initial degree of oxidation, citric acid provides a weakly acidic environment and inhibits some enzymatic browning, and phytate and EDTA salt can chelate trace metal ions such as iron and copper, thereby reducing metal-catalyzed oxidation reactions.

[0034] Kiwi fruit cell wall disruption can be achieved through freezing, mechanical disruption, ultrasonic disruption, or a combination thereof. A combination of low-temperature freezing and mechanical pulverization is preferred. Specifically, pre-treated kiwi fruit pieces are frozen at low temperatures, causing ice crystals to form inside the fruit cells. These are then pulverized under low-oxygen or inert gas protection to obtain the kiwi fruit cell wall disruptor. This method utilizes the physical disruption of cell walls and cell membranes caused by ice crystals to promote the release of intracellular vitamins, polyphenols, and flavonoids, while avoiding browning caused by the combined effects of oxygen, metal ions, and polyphenol oxidase during strong pulverization at room temperature.

[0035] Preferably, the cell-wall breaking process is carried out under low temperature, light-proof, and low-oxygen conditions. The low-oxygen conditions can be achieved by introducing nitrogen, carbon dioxide, or an inert gas. This setup has the advantages of improving the release efficiency of kiwifruit active ingredients and reducing the oxidative loss of vitamin C and polyphenols during cell-wall breaking. Compared to conventional pressing, this cell-wall breaking method is more suitable for preparing kiwifruit active ingredients for cosmetics.

[0036] In a preferred embodiment of the present invention, the cell wall breaking treatment of the kiwi fruit raw material includes the following steps: First, select fresh kiwifruit that is 70-80% ripe, free from mold and obvious mechanical damage as raw material. After washing and removing impurities, the fresh kiwifruit is peeled and cut into pieces 0.5-1.5 cm thick, preferably about 1 cm thick. The cut kiwifruit pieces are immediately placed in a pre-cooled antioxidant protective solution for temporary storage to reduce contact between oxygen and kiwifruit polyphenols, vitamin C, and polyphenol oxidase during the cutting process.

[0037] The pre-cooling antioxidant protective solution preferably consists of ascorbic acid, citric acid, sodium phytate, disodium EDTA, and deionized water. The ascorbic acid content is 0.03–0.08% by mass, preferably 0.05%; the citric acid content is 0.05–0.15% by mass, preferably 0.10%; the sodium phytate content is 0.01–0.05% by mass, preferably 0.03%; the disodium EDTA content is 0.01–0.03% by mass, preferably 0.02%; and the balance is deionized water. The temperature of the pre-cooling antioxidant protective solution is controlled at 3–8°C, preferably about 5°C. The kiwi fruit pieces are soaked in the pre-cooling antioxidant protective solution for 5–20 minutes, preferably 10 minutes.

[0038] After pre-cooling and anti-oxidation treatment, the kiwi fruit pieces are removed and the surface protective liquid is drained off. Then, the kiwi fruit pieces are spread on a clean stainless steel tray, with the thickness of the spread not exceeding 3 cm, preferably not exceeding 2 cm, and then quick-frozen at -40 to -80°C, preferably at -50°C for 30 to 60 minutes, more preferably for about 40 minutes, so that a relatively uniform ice crystal structure is formed inside and outside the kiwi fruit pieces.

[0039] After quick-freezing, the quick-frozen kiwi fruit pieces are transferred to a pre-cooling and pulverizing device. Preferably, the air inside the pulverizing device is replaced with nitrogen before pulverizing to reduce the oxygen content to no more than 5%, more preferably no more than 1%. Then, dry ice pellets and pre-cooled ice blocks are added to the pulverizing device. The amount of dry ice pellets added is 5-15% by weight of the quick-frozen kiwi fruit pieces, preferably 10%; the amount of pre-cooled ice blocks added is 200-400%, preferably 300%. The particle size of the dry ice pellets is preferably 3-8 mm, more preferably about 5 mm; the size of the pre-cooled ice blocks is preferably 1.0-2.0 cm, more preferably about 1.5 cm.

[0040] The above-mentioned materials are pulverized under nitrogen protection. During the pulverization process, the system temperature is maintained at no higher than 5°C, preferably between -5°C and 0°C. The pulverization time is 2–10 minutes, preferably 3–8 minutes, and more preferably about 5 minutes, until the material forms a uniform kiwifruit slush-like pulp. Nitrogen gas can be continuously or intermittently introduced during the pulverization process to maintain a low-oxygen environment; alternatively, a closed-loop cryogenic pulverization device can be used to further reduce oxygen intake.

[0041] Phenolic acid release treatment of black rice bran Black rice bran is preferably first treated with water dispersion to fully swell the cell walls of the bran layer. Then, a phenolic acid release treatment is performed. This phenolic acid release treatment can employ enzyme treatment, microbial pre-fermentation treatment, weak acid treatment, mild alkali treatment, or a combination thereof. Enzyme treatment is preferred to reduce the adverse effects of strong acids and alkalis on anthocyanins, polyphenols, and proteins.

[0042] The enzyme treatment can employ ferulic acid esterase, xylanase, cellulase, hemicellulase, pectinase, Aspergillus oryzae-derived complex enzymes, or combinations thereof. Preferably, an Aspergillus oryzae-derived enzyme preparation containing ferulic acid esterase activity is used. This is because phenolic acids such as ferulic acid in black rice bran are often bound to arabinoxylan, hemicellulose, or lignin-related structures. Ferulic acid esterase can cleave the ester bonds between phenolic acids and polysaccharide chains, converting the bound phenolic acids into a free state or a more easily released form.

[0043] The inventors discovered that phenolic acids such as ferulic acid, p-coumaric acid, and caffeic acid in black rice bran exist in a large quantity in bound form within the cell wall structure, typically linked to arabinoxylan, hemicellulose, and lignin-related structures via ester bonds. When using conventional hot water extraction, alcohol extraction, or direct fermentation, only a small amount of free phenolic acids enters the extract, with most remaining in the cell wall residue, resulting in low utilization of the antioxidants in black rice bran. Therefore, this invention first treats black rice bran to release phenolic acids, thereby increasing the release rate of bound phenolic acids.

[0044] In one embodiment, black rice bran is mixed with water to form a homogeneous suspension system, and the system is adjusted to a slightly acidic condition. Preferably, the pH of the system is controlled between 4.8 and 5.5. The inventors have found that this condition can maintain the stability of anthocyanins and polyphenols and is also conducive to subsequent enzymatic reactions. When the system pH is too low, the activity of some enzymes is inhibited; while when the system pH is too high, it may lead to instability of the anthocyanin structure and increase the risk of oxidation.

[0045] Subsequently, the black rice bran suspension system is subjected to enzymatic treatment. Preferably, the enzyme treatment uses an enzyme preparation capable of releasing ferulic acid, and more preferably, a complex enzyme system containing ferulic acid esterase activity. The complex enzyme system may further include xylanase, hemicellulase, cellulase, or a combination thereof. Ferulic acid esterase can cleave the ester bonds between phenolic acids and cell wall polysaccharides, while xylanase and hemicellulase can further open the cell wall network structure, thereby promoting the release of embedded or bound phenolic acids into the system. Compared with using ferulic acid esterase alone, the complex enzyme system can improve the efficiency of phenolic acid release and reduce the impact of undegraded fiber on subsequent fermentation processes.

[0046] Preferably, the enzyme treatment is carried out at 35–55°C, more preferably at 40–50°C. The treatment time can be adjusted according to the state of the raw materials, usually 1–6 hours, preferably 2–4 hours. During this process, the cell walls of black rice bran gradually loosen and degrade, and ferulic acid, p-coumaric acid, and caffeic acid, which were originally bound to the cell wall structure, are gradually converted into free or readily available forms, thereby improving the availability of phenolic acids in the system.

[0047] In another preferred embodiment, after enzyme treatment, a short-term biotransformation treatment with lactic acid bacteria can be further performed. The inventors discovered that the organic acids produced during lactic acid bacteria metabolism can further promote the loosening of cell wall structure and increase the release of some bound phenolic acids. Simultaneously, lactic acid bacteria fermentation can also reduce the original grain odor of black rice bran, making the resulting product more suitable for subsequent cosmetic applications.

[0048] After the phenolic acid release treatment, the system was subjected to enzyme inactivation, and undegraded large fiber particles were removed by centrifugation, filtration, or membrane separation to obtain the black rice bran phenolic acid release treated product. The treated product showed a significantly increased content of free phenolic acids and a significantly decreased content of crude fiber. Compared to untreated black rice bran, it more readily formed a uniform and stable dispersion system with flavonoids and polyphenols from kiwifruit and active peptides from sea buckthorn seed meal during subsequent fermentation.

[0049] The inventors further discovered that black rice bran treated with phenolic acid release not only improves the utilization rate of phenolic acids such as ferulic acid, but also that the released phenolic acids can synergistically interact with flavonoids, polyphenols, bioactive peptides, and post-fermentative polysaccharides in the subsequent system. Specifically, phenolic acids and polyphenols jointly participate in the free radical scavenging process; hydrogen bonds can form between phenolic acids and bioactive peptides; and a relatively stable dispersion can be formed between phenolic acids and post-fermentative polysaccharides. Therefore, the treated black rice bran not only provides a source of antioxidant activity but also helps improve the stability and activity retention capacity of the entire fermentation system.

[0050] Therefore, the role of black rice bran in this invention is not simply to provide plant extracts or natural pigments, but to serve as a reservoir of bound phenolic acids. By releasing phenolic acids, the utilization rate of phenolic acids is improved, and a foundation is laid for the subsequent formation of an active system in which phenolic acids, polyphenols, organic acids, active peptides, and post-genetic polysaccharides coexist synergistically.

[0051] Peptide processing of sea buckthorn seed meal The inventors discovered that sea buckthorn seed meal, a byproduct of sea buckthorn seed oil extraction, typically contains high levels of protein, polyphenols, and small amounts of residual active lipids. Current technologies mostly treat it as animal feed or dispose of it directly, resulting in low protein resource utilization. Furthermore, directly applying sea buckthorn seed meal to cosmetic systems can lead to problems such as precipitation, turbidity, and a rough skin feel due to its large protein molecular weight and poor solubility, while also limiting its bioavailability.

[0052] Therefore, the present invention first processes sea buckthorn seed meal into peptides to obtain active peptide components with high water solubility and bioavailability.

[0053] In one embodiment, sea buckthorn seed meal is mixed with water to form a homogeneous suspension system. Preferably, the mass ratio of sea buckthorn seed meal to water is 1:4 to 1:10, more preferably 1:5 to 1:8. The inventors have found that within the above ratio range, both sufficient protein hydration and adequate contact between the enzyme and substrate are ensured. If the amount of water added is too low, the system viscosity is high, which is not conducive to protein unfolding; if the amount of water added is too high, the enzymatic hydrolysis efficiency decreases and the subsequent concentration cost increases.

[0054] The pH of the system was then adjusted to a range suitable for protease activity. Food-grade pH adjusters were preferably used to bring the system to a slightly neutral to slightly alkaline state. Under these conditions, the protein structure in sea buckthorn seed meal gradually unfolds, exposing internal peptide bonds, thus creating conditions for subsequent enzymatic hydrolysis.

[0055] In a preferred embodiment, the peptide preparation process employs enzymatic hydrolysis using a protease. The protease can be selected from alkaline proteases, neutral proteases, flavor proteases, papain, trypsin, or combinations thereof. Alkaline proteases can rapidly open the protein backbone structure, while flavor proteases can further cleave hydrophobic peptides and reduce bitterness; therefore, a combined treatment with alkaline and flavor proteases is preferred.

[0056] Preferably, an initial enzymatic hydrolysis is performed using an alkaline protease to degrade large protein molecules into medium-molecular-weight peptides; subsequently, a flavor protease is used for further enzymatic hydrolysis to obtain a higher proportion of small-molecule active peptides. This two-stage enzymatic hydrolysis method avoids the generation of large amounts of bitter peptides during single protease treatment and improves the water solubility and stability of the obtained peptide components.

[0057] During enzymatic hydrolysis, the globulins, albumins, and storage proteins in sea buckthorn seed meal gradually degrade, forming peptides with various molecular weight distributions. Preferably, the average molecular weight of the obtained peptide components is less than 5000 Da, more preferably 300–3000 Da. The inventors have found that peptide components in this molecular weight range exhibit good water dispersibility, skin affinity, and system stability, while not producing significant precipitation or turbidity like large protein molecules.

[0058] In another preferred embodiment, a small amount of yeast extract, yeast extract powder, or amino acid nutrient source may be added during the peptide preparation process. This serves to provide a usable nitrogen source for the subsequent fermentation process, while also promoting the formation of a more stable dispersion system between some peptide fragments and polyphenols.

[0059] After enzymatic hydrolysis, the system undergoes enzyme inactivation treatment. Preferably, this is achieved by heating to inactivate the protease, thereby terminating further protein degradation. Subsequently, large, unhydrolyzed particles are removed by centrifugation, filtration, or membrane separation to obtain the sea buckthorn seed meal peptide-processed product.

[0060] The resulting peptide-treated product contains abundant small-molecule active peptides, free amino acids, and a small amount of residual polyphenols. Among them, the small-molecule active peptides can not only serve as a source of skin nourishment and repair, but also form hydrogen bonds and weak hydrophobic interactions with phenolic acids, polyphenols, and post-genetic polysaccharides in the subsequent system, thereby improving the dispersion stability of the active system.

[0061] The inventors further discovered that, compared to untreated sea buckthorn seed meal, the peptide-treated sea buckthorn seed meal not only improved protein resource utilization but also significantly enhanced the stability of the subsequent fermentation system. Normally, polyphenols tend to aggregate and precipitate at high concentrations, but the small molecule peptides obtained in this invention can form a dynamic dispersion with phenolic acids and polyphenols, thereby reducing the aggregation of active substances. Furthermore, the small molecule peptides can also improve the efficiency of nitrogen source utilization by microorganisms during subsequent fermentation and promote the generation of post-fermentation metabolites.

[0062] Therefore, the sea buckthorn seed meal in this invention serves not only as a source of active peptides but also as an important active component linking phenolic acids, polyphenols, and post-biotic polysaccharides. The sea buckthorn seed meal treated with peptides provides an important foundation for the subsequent formation of an active system in which phenolic acids, polyphenols, organic acids, active peptides, and post-biotic polysaccharides coexist synergistically.

[0063] The inventors unexpectedly discovered that when sea buckthorn seed meal treated with peptides, black rice bran treated with phenolic acid release, and kiwifruit treated with cell wall disruption were introduced into the fermentation system, the resulting system not only did not exhibit the increased protein precipitation and color instability typically expected by those skilled in the art, but also showed better dispersion stability and activity retention. This phenomenon indicates that small molecule active peptides not only play a repairing role in this system, but also participate in the stabilization process of polyphenols and phenolic acids, thus producing a comprehensive technical effect that differs from that of fermented plant products alone.

[0064] Mixed enzymatic hydrolysis treatment Kiwi fruit cell wall-breaking material, black rice bran phenolic acid release material, and sea buckthorn seed meal peptide-based material are mixed to obtain a ternary mixed substrate. The ternary mixed substrate is further subjected to enzymatic hydrolysis. The enzymatic hydrolysis may include pectinase, cellulase, hemicellulase, or a combination thereof. Preferably, pectinase, cellulase, and hemicellulase are used together.

[0065] Pectinase is used to degrade the pectin-like structures in kiwifruit, reducing the viscosity and heaviness of the system. Cellulase and hemicellulase are used to further release polyphenols and flavonoids from the plant cell walls and reduce sedimentation caused by coarse fiber particles. This step is not simply to increase the extraction rate, but also to regulate the dispersion stability and skin feel of the system. If pectin degradation is insufficient, the subsequent serum may be viscous and stringy; if degradation is excessive, it may reduce the moisturizing film of the system. Therefore, moderate-intensity enzymatic hydrolysis conditions are preferred, so that the pectin is partially degraded into oligopectin, rather than completely destroyed.

[0066] In a preferred embodiment, the mixed enzymatic hydrolysis is carried out under weakly acidic conditions. Weakly acidic conditions are beneficial for maintaining the stability of kiwifruit polyphenols, black rice anthocyanins, and phenolic acids, while also being suitable for the activity of most plant cell wall degrading enzymes. After this step, the kiwifruit polyphenols, black rice bran phenolic acids, and sea buckthorn seed peptides in the system can enter the fermentation stage in a more uniform aqueous dispersion.

[0067] In a preferred embodiment, the kiwifruit cell wall-breaking treatment product, the black rice bran phenolic acid release treatment product, and the sea buckthorn seed meal peptide treatment product obtained above are mixed and further subjected to mixed enzymatic hydrolysis treatment to obtain a composite substrate system suitable for subsequent fermentation.

[0068] Specifically, 82 parts of kiwifruit cell wall-breaking treatment product, 10 parts of black rice bran phenolic acid release treatment product, and 8 parts of sea buckthorn seed meal peptide treatment product were added to a jacketed reactor and stirred until homogeneous. Then, an appropriate amount of deionized water was added to control the solid content of the system at approximately 12 wt%. Preferably, a citric acid-sodium citrate buffer system was used to adjust the pH of the system to 4.8–5.2, more preferably to approximately 5.0.

[0069] The inventors discovered that if the system pH is below 4.5, the activity of some plant cell wall degrading enzymes decreases; while when the system pH is above 5.5, the stability of anthocyanins and phenolic acids derived from black rice bran decreases, and they are prone to oxidative browning. Therefore, controlling the system within the aforementioned weakly acidic range is beneficial for balancing enzyme activity and the stability of active ingredients.

[0070] A complex enzyme system is added to the mixed system. The complex enzyme system preferably includes pectinase, cellulase, and hemicellulase. The amount of pectinase added is preferably 0.10–0.30% of the total mass of the mixed system, more preferably 0.20%; the amount of cellulase added is preferably 0.03–0.15%, more preferably 0.08%; and the amount of hemicellulase added is preferably 0.02–0.10%, more preferably 0.05%.

[0071] Pectinase mainly acts on the pectin structure in the cell wall of kiwifruit, gradually degrading high molecular weight pectin into oligomeric pectin and soluble pectin fragments; cellulase can open the cellulose skeleton in the plant cell wall, increasing the release of flavonoids and polyphenols from kiwifruit; hemicellulase further acts on the hemicellulose structure in the cell wall of black rice bran, further releasing residual bound phenolic acids.

[0072] The system is then heated to 40–45°C, preferably around 42°C, while maintaining slow stirring. The stirring speed is preferably controlled at 150–300 rpm, more preferably around 200 rpm. The enzymatic hydrolysis treatment lasts for 60–180 min, preferably around 120 min.

[0073] During enzymatic hydrolysis, kiwifruit-derived pectin gradually transforms from a high-molecular-weight state into oligomeric pectin; the residual cell wall structure of black rice bran further loosens; and incompletely dissociated protein aggregates in sea buckthorn seed meal further disperse. Simultaneously, flavonoids, polyphenols, and vitamin precursors from kiwifruit, phenolic acids from black rice bran, and bioactive peptides from sea buckthorn gradually and uniformly disperse in the same system.

[0074] In a further preferred embodiment, after approximately 60 minutes of enzymatic hydrolysis, yeast extract, trehalose, and β-glucan are added to the system. Preferably, the amount of yeast extract added is 0.05–0.20% of the total mass of the system, more preferably about 0.10%; the amount of trehalose added is preferably 0.20–1.00%, more preferably about 0.50%; and the amount of β-glucan added is preferably 0.05–0.30%, more preferably about 0.10%.

[0075] The inventors discovered that trehalose can protect the vitamins, polyphenols, and flavonoids from kiwifruit during enzymatic hydrolysis, thereby reducing oxidative losses; β-glucan can improve the colloidal stability of the system; and yeast extract can provide a usable nitrogen source for the subsequent fermentation process, improving the growth efficiency of lactic acid bacteria and yeast.

[0076] After enzymatic hydrolysis, the system is heated to 60–70°C, preferably about 65°C, and held for 0.8–1.5 h to inactivate the enzyme and terminate the enzymatic reaction. Then, it is rapidly cooled to 30–35°C, preferably about 32°C, to obtain the mixed enzymatic hydrolysate.

[0077] The inventors discovered that after the above-mentioned mixed enzymatic hydrolysis treatment, the release of flavonoids, polyphenols, and vitamin precursors from kiwifruit was significantly increased; the content of free phenolic acids from black rice bran was further increased; and the dispersibility of active peptides from sea buckthorn was significantly improved. Simultaneously, some pectin was degraded into oligopectin, rather than completely degraded into monosaccharides. The resulting oligopectin can form a relatively stable natural colloidal dispersion system together with phenolic acids, polyphenols, and active peptides.

[0078] Of particular note is that those skilled in the art generally believe that high-polyphenol systems and high-active peptide systems are prone to aggregation, turbidity, or sedimentation when coexisting. However, the inventors unexpectedly discovered that the oligopectin formed after the above-mentioned mixed enzymatic hydrolysis treatment can serve as a natural dispersion medium, maintaining the uniform dispersion of phenolic acids, polyphenols, and active peptides, and improving the utilization efficiency of the substrate by microorganisms during subsequent fermentation. Therefore, this step not only improves the release of active substances but also provides an important foundation for the subsequent formation of an active system in which phenolic acids, polyphenols, organic acids, active peptides, and post-biotic polysaccharides coexist synergistically.

[0079] Lactic acid bacteria fermentation treatment After mixed enzymatic hydrolysis, the resulting system is subjected to lactic acid bacteria fermentation. The lactic acid bacteria can be *Lactobacillus plantarum*, *Lactobacillus rhamnosus*, *Lactobacillus paracasei*, *Lactobacillus fermentum*, or a combination thereof. *Lactobacillus plantarum* is preferred. *Lactobacillus plantarum* has strong adaptability to plant substrates, can utilize some sugars in kiwifruit and grain substrates, and produce lactic acid and other metabolites.

[0080] The main purposes of lactic acid bacteria fermentation include: first, reducing residual sugar in the kiwifruit system, thereby reducing the stickiness and microbial risks associated with high-sugar plant juices; second, producing organic acids such as lactic acid, which gives the system a gentle keratin conditioning and brightening effect; third, keeping plant polyphenols and phenolic acids in a relatively stable acidic environment, reducing oxidative browning; and fourth, improving the plant odor from black rice bran and sea buckthorn seed meal.

[0081] The inventors discovered that after mixed enzymatic hydrolysis, flavonoids, polyphenols, and organic acid precursors from kiwifruit, phenolic acids from black rice bran, and bioactive peptides from sea buckthorn were already in a high release state. However, the system still contained a certain amount of glucose, fructose, and some fermentable oligosaccharides. Simultaneously, some plant tissue-derived odors remained, and the stability of the polyphenol and phenolic acid system still had room for further improvement. Therefore, this invention preferably first performs lactic acid bacteria fermentation treatment.

[0082] Lactic acid bacteria fermentation can utilize fermentable sugars in the system to generate lactic acid and other organic acids, thereby reducing residual sugar content. On the other hand, it can create a suitable acidic environment, improve the stability of phenolic acids and polyphenols, and improve the raw and off-flavors of the plant raw materials themselves.

[0083] In a preferred embodiment, the above-mentioned mixed enzymatic hydrolysate is cooled to 30–35°C, preferably controlled at around 32°C. The pH of the system is adjusted to 5.0–5.5, preferably about 5.2, using lactic acid or citric acid. Then, a lactic acid bacteria seed culture is added to the system.

[0084] The lactic acid bacteria are preferably selected from Lactobacillus plantarum, Lactobacillus rhamnosus, Lactobacillus paracasei, Lactobacillus fermentum, or combinations thereof. Lactobacillus plantarum is more preferred.

[0085] The inventors discovered that *Lactobacillus plantarum* has a good ability to utilize fructose, glucose and oligosaccharides from kiwifruit, and can also produce high levels of lactic acid and extracellular polysaccharides, which is beneficial to the stability of the subsequent active system.

[0086] In a preferred embodiment, the inoculation amount of Lactobacillus plantarum seed liquid is 1.0 to 5.0% of the total mass of the fermentation system, more preferably 2.0 to 3.0%, and even more preferably about 2.5%.

[0087] The *Lactobacillus plantarum* seed culture is preferably obtained by pre-culturing in MRS medium, and its viable cell concentration is preferably not less than 1 × 10⁻⁶. 8 CFU / mL, more preferably not less than 5×10 8 CFU / mL. After inoculation, fermentation is carried out at 30–37°C. The preferred fermentation temperature is 32–35°C; more preferably 33°C.

[0088] During fermentation, slow stirring is used to maintain system homogeneity. The stirring speed is preferably controlled at 50–150 rpm; more preferably at approximately 100 rpm. The fermentation time is preferably 12–36 h; more preferably 18–30 h; and even more preferably approximately 24 h.

[0089] During fermentation, *Lactobacillus plantarum* gradually utilizes glucose and fructose from kiwifruit for metabolism, producing lactic acid and small amounts of other organic acids. As fermentation progresses, the pH of the system gradually decreases. Preferably, the fermentation endpoint is controlled at pH 4.2–4.8; more preferably at 4.5 ± 0.2.

[0090] The inventors discovered that when the endpoint pH is higher than 4.8, the residual sugar content is still too high, posing a risk of microbial contamination during subsequent storage; while when the endpoint pH is lower than 4.0, it may lead to a decrease in the stability of some active peptides and increase the risk of irritation when combined with nicotinamide in the future.

[0091] Therefore, controlling the fermentation endpoint within the above-mentioned range can balance activity release, stability, and skin suitability. During fermentation, a small amount of nutrients can be added to the system. Preferably, the following are added: 0.05–0.20% yeast extract and 0.10–0.50% trehalose.

[0092] Yeast extract is used to maintain the growth activity of lactic acid bacteria; trehalose can reduce the loss of polyphenols and phenolic acids during fermentation.

[0093] The inventors discovered that, in the presence of trehalose, the retention rates of flavonoids from kiwifruit and phenolic acids from black rice bran were significantly improved.

[0094] The system is then cooled to 28–32°C, preferably about 30°C, for subsequent yeast fermentation.

[0095] The inventors further discovered that after lactic acid bacteria fermentation, flavonoids from kiwifruit and phenolic acids from black rice bran maintain good stability in an acidic environment; some high-molecular-weight pectin is further converted into oligomeric pectin; and some protein residues are further degraded into available amino acids and short peptides.

[0096] More importantly, the lactic acid produced by lactic acid bacteria fermentation not only exists as an active organic acid, but also promotes the release of cell wall metabolites during subsequent yeast fermentation.

[0097] Surprisingly, those skilled in the art generally believe that high-concentration polyphenol systems are prone to oxidative browning during fermentation. However, the inventors discovered that after lactic acid bacteria fermentation based on black rice bran phenolic acid release treatment, sea buckthorn seed meal peptide production treatment, and mixed enzymatic hydrolysis treatment, the system not only did not show obvious browning, but also exhibited a higher phenolic acid retention rate and better colloidal stability.

[0098] The inventors believe that, although not limited by theory, this phenomenon may be related to the weakly acidic environment formed by lactic acid bacteria, the natural colloidal protective effect of oligopectin, and the hydrogen bond interaction between active peptides and phenolic acids.

[0099] Therefore, the lactic acid bacteria fermentation treatment in this invention is not only used to produce lactic acid and reduce residual sugar, but more importantly, it promotes the formation of a more stable dispersion system among phenolic acids, polyphenols, active peptides and oligopectin, providing a foundation for subsequent yeast fermentation and the final formation of an active system in which phenolic acids, polyphenols, organic acids, active peptides and post-biotic polysaccharides coexist synergistically.

[0100] Yeast fermentation treatment Following lactic acid bacteria fermentation, yeast fermentation is further carried out. The yeast may be *Saccharomyces cerevisiae*, *Kluyveromyces martensii*, *Hansenula polymorpha*, or a combination thereof. *Saccharomyces cerevisiae* is preferred. Yeast fermentation can further consume some of the residual sugars and release amino acids, nucleotides, glutathione, and cell wall polysaccharide-related components.

[0101] Yeast-derived polysaccharides mainly include β-glucan, mannan, or combinations thereof. β-glucan can improve skin comfort and barrier repair, while mannan can improve the hydration and dispersion of the system. Yeast fermentation can also produce reducing metabolites, such as glutathione, which help reduce the oxidative stress of polyphenols and phenolic acids.

[0102] In a preferred approach, yeast fermentation occurs after lactic acid bacteria fermentation, rather than being inoculated simultaneously with the lactic acid bacteria. This is because pre-fermentation by lactic acid bacteria lowers the pH and inhibits unwanted microorganisms, while also reducing residual sugar levels in the system. Subsequent yeast fermentation, in a milder sugar environment, reduces excessive gas production and off-flavors. If both are inoculated simultaneously, competition for substrate between different microorganisms can easily lead to unstable fermentation endpoints. Sequential fermentation allows for greater control over the generation of organic acids, reduction of residual sugars, and release of yeast metabiotics.

[0103] The inventors discovered that after lactic acid bacteria fermentation, most of the fermentable sugars in the system are consumed, while lactic acid and other organic acids gradually accumulate, and the system pH drops to a suitable range. Simultaneously, flavonoids, polyphenols, and organic acid precursors from kiwifruit, phenolic acids from black rice bran, and active peptides from sea buckthorn are already in a high-release state. However, the post-biotic components in the system are still relatively limited at this point, especially the active components such as yeast-derived β-glucan, mannan, nucleotides, and glutathione, which have not yet been formed. Therefore, this invention further employs yeast fermentation to increase the content of post-biotic active substances in the system and further improve the system's stability and skin applicability.

[0104] In a preferred embodiment, the fermentation broth after lactic acid bacteria fermentation is completed is cooled to 28–32°C, preferably controlled at around 30°C. The pH of the system is then measured, preferably controlled between 4.3 and 4.8, more preferably around 4.5.

[0105] The inventors discovered that this pH range can maintain a stable acidic environment for lactic acid bacteria fermentation while also being conducive to subsequent yeast growth and metabolism. If the system acidity is too high, it may inhibit yeast activity; if the acidity is too low, it is not conducive to maintaining the stability of phenolic acids and polyphenols.

[0106] Subsequently, yeast seed culture is inoculated into the system. The yeast is preferably selected from *Saccharomyces cerevisiae*, *Kluyveromyces martensii*, *Hansenula polymorpha*, or a combination thereof. *Saccharomyces cerevisiae* is more preferred.

[0107] The inventors discovered that brewer's yeast can not only further utilize the residual sugars in the system, but also produce a relatively rich amount of amino acids, nucleotides, glutathione and cell wall polysaccharide precursors, which is particularly beneficial for the formation of a postbiotic active system.

[0108] In a preferred embodiment, the inoculation amount of yeast seed liquid is 0.5 to 3.0% of the total mass of the fermentation system, more preferably 1.0 to 2.0%, and even more preferably about 1.5%.

[0109] The yeast seed culture is preferably obtained by pre-culturing in YPD medium, and its viable cell concentration is preferably not less than 1×10⁻⁶. 8 CFU / mL, more preferably not less than 5×10 8 CFU / mL.

[0110] After inoculation, yeast fermentation is carried out at 28–33°C. Preferably, the fermentation temperature is controlled at 29–31°C; more preferably, about 30°C. During fermentation, slow stirring is used to maintain system homogeneity. Preferably, the stirring speed is controlled at 50–120 rpm; more preferably, about 80 rpm. The fermentation time is preferably 12–36 h; more preferably 18–24 h; and even more preferably about 20 h.

[0111] During fermentation, yeast gradually utilizes the residual sugars in the system for metabolism, while releasing metabolites such as amino acids, nucleotides, and glutathione.

[0112] The inventors discovered that yeast fermentation based on lactic acid bacteria pre-fermentation significantly reduces the generation of alcoholic odor and off-flavors during fermentation, and increases the accumulation of glutathione and cell wall polysaccharide precursors compared to direct yeast fermentation.

[0113] In a preferred embodiment, yeast extract and trehalose are added to the system approximately 4–8 hours after the start of yeast fermentation.

[0114] Preferred ingredients include: 0.05-0.20 wt% yeast extract, more preferably about 0.10 wt%; and 0.10-0.50 wt% trehalose, more preferably about 0.30 wt%.

[0115] Yeast extract can provide yeast with additional nitrogen source and growth factors; trehalose can reduce the oxidative loss of polyphenols and phenolic acids during fermentation and protect the post-biotic active components formed subsequently.

[0116] During fermentation, the residual sugar in the system further decreases, while the yeast cells gradually accumulate cell wall polysaccharides.

[0117] Preferably, the fermentation endpoint is controlled as follows: residual reducing sugar content is less than 20% of the initial content; total organic acid content is maintained between 0.8 and 2.5 wt%; and the system pH is maintained between 4.2 and 4.8. After fermentation, it is preferably terminated by heating. Specifically, the system is heated to 50–60°C and held for 30–60 min.

[0118] The inventors discovered that this condition can effectively terminate yeast metabolism while avoiding significant damage to flavonoids, polyphenols, phenolic acids, and bioactive peptides caused by high temperatures.

[0119] Yeast metabiotic release and post-processing Subsequently, a cell wall-releasing enzyme system was added to the system to promote the release of yeast metatrophs. Preferred treatment involved a combination of β-1,3-glucanase and mannanase.

[0120] The preferred amount of β-1,3-glucanase is 0.02–0.10 wt%, more preferably about 0.05 wt%; the preferred amount of mannanase is 0.01–0.08 wt%, more preferably about 0.03 wt%. The preferred treatment temperature is 45–55°C, more preferably about 50°C. The preferred treatment time is 2–6 h, more preferably about 4 h.

[0121] During this process, the yeast cell wall gradually undergoes partial degradation, releasing β-glucan, mannan, nucleotides, and cell wall-related postbiotic components.

[0122] The inventors discovered that this treatment method, compared to traditional mechanical cell disruption, can reduce the loss of activity caused by high-energy processing while improving the efficiency of metagenic release. After treatment, cell debris is removed by centrifugation and filtration. Centrifugation at 8000 rpm for 10–20 min is preferred; centrifugation for approximately 15 min is more preferable.

[0123] The yeast fermentation product was then obtained by filtration through a 100-mesh filter and a 0.45 μm microfiltration.

[0124] The inventors further discovered that after yeast fermentation and epigenetic release treatment, the system not only increased the epigenetic active components, but also improved the stability of the polyphenol and phenolic acid system.

[0125] Surprisingly, those skilled in the art generally believe that high-concentration polyphenol systems are prone to turbidity or sedimentation when coexisting with polysaccharide systems. However, the inventors discovered that when β-glucan and mannan, formed after lactic acid bacteria fermentation, yeast fermentation, and post-biotic release treatment, coexist with oligopectin and bioactive peptides, the system exhibits better dispersion and storage stability.

[0126] The inventors believe that, although not limited by theory, this phenomenon may be related to the hydrophilic network structure formed by β-glucan and mannan. This structure can reduce the aggregation tendency between phenolic acids, polyphenols, and bioactive peptides, and improve their dispersion in the aqueous phase.

[0127] Therefore, the yeast fermentation process in this invention is not only used to obtain post-genetic active components, but also to further promote the formation of a synergistic active system among phenolic acids, polyphenols, organic acids, active peptides and post-genetic polysaccharides, thereby providing a material basis for subsequent comprehensive effects such as whitening and brightening, anti-oxidation, barrier repair and moisturizing.

[0128] The resulting co-fermented biogenic composition is preferably a water-soluble or water-dispersible liquid, and can also be further prepared into a concentrated liquid, lyophilized powder, spray-dried powder, or microencapsulated powder. If lyophilized powder is prepared, trehalose, mannitol, or β-cyclodextrin can be added as lyophilization protectants to improve reconstitution stability and the retention rate of active ingredients.

[0129] The resulting co-fermented post-fermentation metabolite composition preferably contains phenolic acids, polyphenols, organic acids, bioactive peptides, and post-fermentation polysaccharides. Specifically, the polyphenols are mainly derived from kiwifruit and some black rice bran; the phenolic acids are mainly derived from black rice bran; the organic acids are mainly derived from kiwifruit and fermentation metabolism; the bioactive peptides are mainly derived from sea buckthorn seed meal; and the post-fermentation polysaccharides are mainly derived from yeast.

[0130] The technological value of this composition lies in the fact that different active ingredients act on different skin pathways. Phenolic acids and polyphenols can reduce oxidative stress-related dullness; organic acids can gently promote keratinocyte renewal, resulting in a more even skin tone; active peptides can enhance skin nourishment and repair; and post-fermented polysaccharides can reduce irritation and improve barrier comfort. The presence of these ingredients within the same fermented post-fermented system makes it easier to achieve a continuous and synergistic skincare effect compared to adding kiwi extract, black rice bran extract, or sea buckthorn seed peptides individually.

[0131] Overall formulation of cosmetic composition The present invention further provides a cosmetic composition containing the composition. The cosmetic composition may be a serum, lotion, cream, spray, gel, mask, freeze-dried preparation, or other topical cosmetic. Preferably, it is a whitening, brightening, and repairing serum.

[0132] In a preferred embodiment, the cosmetic composition comprises: a skin care composition containing kiwi juice, niacinamide, beta-glucan, panthenol, betaine, inositol, phytate, trehalose, amino acid buffer, polyol moisturizer, thickening stabilizer, skin feel modifier, and cosmetically acceptable carrier.

[0133] The preferred amount of a skincare composition containing kiwi juice in the formulation is 3–15 wt%, more preferably 5–12 wt%, and even more preferably about 8 wt%. If the amount is too low, the contribution of fermented active ingredients will be insufficient; if the amount is too high, it may lead to an unpleasant burden in terms of color, odor, acidity, and stickiness. An addition of about 8 wt% achieves a good balance between efficacy, stability, and skin feel.

[0134] The preferred dosage of niacinamide in the formulation is 1–5 wt%, more preferably 2–3 wt%, and even more preferably about 2.5 wt%. Niacinamide can inhibit the transport of melanin to keratinocytes and forms a brightening effect through different pathways with polyphenols, phenolic acids, and organic acids in a skin care composition containing kiwi juice. Too low a dosage of niacinamide will result in insufficient whitening contribution; too high a dosage may increase skin discomfort in some individuals.

[0135] β-glucan and panthenol are used to improve the skin barrier repair and soothing properties. β-glucan can be 0.05–1.0 wt%, preferably about 0.5 wt%; panthenol can be 0.1–1.0 wt%, preferably about 0.5 wt%. When both are present in conjunction with organic acids in a skincare composition containing kiwi juice, they can reduce the stinging and tightness caused by acidic active ingredients and improve formulation tolerance.

[0136] Betaine and inositol are used to improve moisturizing, comfort, and the feel of fermented products on the skin. Betaine may be 0.3–1.5 wt%, preferably about 0.8 wt%; inositol may be 0.1–0.8 wt%, preferably about 0.3 wt%. Betaine has good hydrating properties and can reduce the stickiness caused by polyols and fermented products; inositol can improve skin softness and comfort, making the product feel more refreshing.

[0137] Phytates, trehalose, and amino acid buffers are used to improve formulation stability. Phytates are preferably sodium phytate, potassium phytate, or a combination thereof, and are used in amounts of 0.005–0.10 wt%, preferably about 0.03 wt%. Phytates can chelate trace metal ions, reducing metal-ion-induced oxidation of polyphenols and phenolic acids. Trehalose is used in amounts of 0.05–2.0 wt%, preferably about 0.5 wt%, to protect bioactive peptides, polysaccharides, and fermentation metabolites. Amino acid buffers are preferably arginine, lysine, histidine, or a combination thereof, more preferably arginine. Their function is to adjust and buffer the pH of the system, allowing nicotinamide and acidic fermentation products to coexist for a long period.

[0138] The pH of the cosmetic composition is preferably 5.0–6.0, more preferably 5.3–5.6. This range has clear formulation significance. If the pH is too low, the long-term stability and skin tolerance of niacinamide may decrease; if the pH is too high, polyphenols, phenolic acids, and anthocyanins are easily oxidized and discolored, and the brightening effect of organic acids is weakened. A pH of 5.3–5.6 can balance the stability of niacinamide, the antioxidant stability of polyphenols, the mild effect of organic acids, and skin suitability.

[0139] Composition of serum formula In a preferred serum, the formula includes the following components: Water, remaining amount; Disodium EDTA, 0.01–0.10 wt%, preferably about 0.05 wt%; Glycerin, 2–6 wt%, preferably about 5 wt%; Isopentylene glycol, 2–8 wt%, preferably about 5 wt%; Nicotinamide, 1–5 wt%, preferably about 2.5 wt%; PEG / PPG-14 / 7 dimethyl ether, 0.3–2 wt%, preferably about 1 wt%; Betaine, 0.3–1.5 wt%, preferably about 0.8 wt%; Inositol, 0.1–0.8 wt%, preferably about 0.3 wt%; Trehalose, 0.1–1.0 wt%, preferably about 0.5 wt%; A skincare composition containing kiwi juice, 5–12 wt%, preferably about 8 wt%; β-glucan, 0.1–0.8 wt%, preferably about 0.5 wt%; Panthenol, 0.2–1.0 wt%, preferably about 0.5 wt%; Dipotassium glycyrrhizate, 0.03–0.20 wt%, preferably about 0.10 wt%; Purslane extract, 0.1–1.0 wt%, preferably about 0.5 wt%; Sodium polyglutamate, 0.01–0.10 wt%, preferably about 0.05 wt%; p-Hydroxyacetophenone, 0.1–0.5 wt%, preferably about 0.3 wt%; 1,2-Hexanediol, 0.3–1.0 wt%, preferably about 0.5 wt%; Octyl glycol, 0.05–0.20 wt%, preferably about 0.1 wt%; Ethylhexylglycerol, 0.02–0.10 wt%, preferably about 0.05 wt%; Sodium phytate, 0.01–0.08 wt%, preferably about 0.03 wt%; Arginine and citrate, in appropriate amounts, are used to adjust the pH of the system to 5.3–5.6.

[0140] The formulation may further contain xanthan gum, hydroxyethyl cellulose, ammonium polyacrylamide dimethyl taurate, or a combination thereof, to adjust the viscosity and stability of the system. Preferably, a small amount of xanthan gum is used in combination with ammonium polyacrylamide dimethyl taurate. Xanthan gum provides basic suspension stability, while ammonium polyacrylamide dimethyl taurate provides a refreshing, smooth gel feel. A small amount of hydroxyethyl cellulose may be added to improve application continuity and reduce water-like breakage.

[0141] The formulation may also contain small amounts of isododecane, polydimethylsiloxane, C8-12 triglycerides, silica, or combinations thereof. These components are used to improve spreadability and aftertaste. It is preferable to control the amount of the oil-silicone system at a low level, for example, 0.3–1.0 wt% polydimethylsiloxane and 0.1–0.6 wt% isododecane. Excessive amounts will mask the moist feel of the fermented active ingredients and produce a false slippery texture; insufficient amounts will fail to improve the sticky aftertaste caused by the fermented products and polysaccharides.

[0142] Preparation method of serum The essence can be prepared as follows: First, water, disodium EDTA, glycerin, isopentyl glycol, niacinamide, betaine, inositol, trehalose, and other aqueous phase components are mixed and dissolved; then xanthan gum, hydroxyethyl cellulose, or polyacrylamide dimethyl taurate ammonium are pre-dispersed in glycerin or polyol, and then added to the aqueous phase for full hydration; subsequently, a small amount of skin feel modifier is added and homogenized or stirred to make the system uniform; after the temperature drops below 45°C, the co-fermented biogenic composition, β-glucan, panthenol, dipotassium glycyrrhizate, purslane extract, sodium polyglutamate, p-hydroxyacetophenone, 1,2-hexanediol, caprylyl glycol, ethylhexylglycerin, and phytate are added; finally, the pH is adjusted to 5.3-5.6 with arginine, citric acid, or citrate, filtered, and bottled.

[0143] Skincare compositions containing kiwi juice are preferably added at temperatures below 45°C. This is because polyphenols, phenolic acids, active peptides, and post-biotic polysaccharides may oxidize, degrade, or change their dispersion state at high temperatures. Adding at low temperatures reduces the loss of active ingredients and also lowers the risk of changes in color and odor.

[0144] Nicotinamide is preferably added early in the aqueous phase to ensure complete dissolution and uniform distribution. Phytate and disodium EDTA can be added early to pre-complex metal ions in the aqueous phase; alternatively, they can be added partially later to protect phenolic acids and polyphenols in the post-fermentation biogenic composition. Trehalose can be added simultaneously with or before the post-fermentation biogenic composition to improve the stability of active peptides and polysaccharides in the formulation.

[0145] The technical effects of this invention do not simply arise from the superposition of multiple plant materials. Typically, when kiwifruit, black rice bran, and sea buckthorn seed meal are present simultaneously, those skilled in the art might expect the system to exhibit problems such as darkening of color, increased sedimentation, complex odor, and a sticky texture. Kiwifruit is rich in sugar, pectin, and polyphenols, making it prone to browning and gas production; black rice bran contains anthocyanins and bound phenolic acids, and its color stability is significantly affected by pH; sea buckthorn seed meal contains protein and polyphenol residues, easily leading to turbidity and sedimentation. Therefore, directly mixing these three does not necessarily yield a stable cosmetic ingredient.

[0146] This invention first releases bound phenolic acids from black rice bran, then converts proteins in sea buckthorn seed meal into active peptides, followed by enzymatic hydrolysis and continuous fermentation with kiwifruit cell wall-breaking material. This process transforms various active ingredients from coarse particles, high-sugar juice, or large-molecule proteins into a dispersed form of phenolic acids, polyphenols, organic acids, active peptides, and post-generative polysaccharides. This treatment converts potentially unstable plant components into an active system with synergistic skincare benefits.

[0147] More importantly, this invention discovers that fermented biogenic compositions containing organic acids can coexist with niacinamide for a long time in a suitable buffering system, while simultaneously maintaining brightening effects and low irritation. It is generally believed that there are stability and irritation risks when acidic ferments are combined with niacinamide; however, this invention alleviates this contradiction through a combination of amino acid buffers, phytates, trehalose, and a low-oil silicone-based skin-feel system. The resulting formulation not only maintains the color stability of polyphenols and phenolic acids but also reduces the stinging sensation caused by organic acids and improves the sticky aftertaste of fermented products.

[0148] Even after introducing three raw materials—kiwifruit, black rice bran, and sea buckthorn seed meal—that can easily lead to issues with color, odor, and stability, the resulting composition still achieves good appearance stability and skin feel. In a complex system containing polyphenols, phenolic acids, organic acids, active peptides, and polysaccharides, it still achieves stable compounding with niacinamide. While enhancing whitening, brightening, and antioxidant effects, it also provides barrier repair, low irritation, and a refreshing feel. This comprehensive effect cannot be expected from any single raw material or conventional plant fermentation process.

[0149] The following is a detailed description with reference to specific embodiments.

[0150] Example 1 Preparation of skin care composition containing kiwi juice Fresh kiwifruit that is 80% ripe, free from mold and obvious mechanical damage, is washed with running water, peeled, and cut into pieces approximately 1.0 cm thick. The cut kiwifruit pieces are immediately immersed in a pre-cooling antioxidant protective solution for 10 minutes. This pre-cooling antioxidant protective solution consists of 0.05 wt% ascorbic acid, 0.10 wt% citric acid, 0.03 wt% sodium phytate, 0.02 wt% disodium EDTA, and the remainder deionized water. The temperature of the protective solution is controlled at 5°C.

[0151] After soaking, remove the kiwi fruit pieces and drain off the surface liquid. Spread each 82 kg piece of kiwi fruit on a stainless steel tray, with a thickness of approximately 2 cm. Quick-freeze at -50°C for 40 minutes. After quick-freezing, transfer the frozen kiwi fruit pieces to a pre-cooling grinder. First, purge the air in the grinding chamber with nitrogen to reduce the oxygen content to below 1.0%. Then, add 8.2 kg of dry ice particles (approximately 5 mm in diameter) and 246 kg of pre-cooled ice blocks (approximately 1.5 cm in diameter) to the grinder. Perform low-temperature grinding for 5 minutes under nitrogen protection, controlling the material temperature between -5°C and 0°C during the grinding process.

[0152] Take another 10 kg of black rice bran and add 80 kg of deionized water, stirring to form a uniform suspension. Adjust the pH to 5.0 using a citric acid-sodium citrate buffer system, then add 0.15 wt% ferulic acid esterase, 0.10 wt% xylanase, and 0.05 wt% hemicellulase, all based on the total mass of the black rice bran suspension. Heat the system to 45℃ and treat with enzymes at 200 rpm for 2 h. After enzyme treatment, inoculate the system with 1.0 wt% of a pre-fermented Lactobacillus plantarum seed culture, the viable cell concentration of which is approximately 1.0 × 10⁻⁶. 9 The concentration of CFU / mL was pre-fermented at 32℃ for 8 h. After pre-fermentation, the system was heated to 85℃ and held for 15 min for enzyme inactivation and deactivation treatment, and then cooled to room temperature.

[0153] The inactivated black rice bran treatment solution was centrifuged at 8000 rpm for 15 min, the supernatant was collected, and then concentrated at a low temperature below 45°C using a vacuum concentration method until the soluble solids content was approximately 18 wt%. The resulting concentrate was used as the black rice bran phenolic acid release product.

[0154] Take 8 kg of defatted sea buckthorn seed meal and add 48 kg of deionized water, stirring to form a homogeneous suspension. Adjust the pH to 8.0 using food-grade sodium hydroxide solution, add 0.30 wt% alkaline protease, and hydrolyze at 50℃ for 2 h; then adjust the pH to 7.0, add 0.15 wt% flavor protease, and continue hydrolysis for 2 h. All protease additions are based on the total mass of the sea buckthorn seed meal suspension. After hydrolysis, heat the system to 65℃ and maintain for 1 h to inactivate the enzymes, then cool to room temperature and centrifuge at 8000 rpm for 15 min, collecting the supernatant. Concentrate the supernatant under vacuum below 45℃ to a soluble solids content of approximately 20 wt%, using this as the peptide-processing product from sea buckthorn seed meal.

[0155] The ternary treatments were then mixed. Based on converted solids, the kiwifruit cell-wall breaking treatment, black rice bran phenolic acid release treatment, and sea buckthorn seed meal peptide treatment were mixed to achieve a final mixture with a solids mass ratio of 82:10:8 from kiwifruit, black rice bran, and sea buckthorn seed meal. After mixing, deionized water was added to adjust the total solids content to approximately 12 wt%, and the pH was adjusted to 5.0 using a citric acid-sodium citrate buffer system.

[0156] A complex enzyme system consisting of pectinase, cellulase, and hemicellulase was added to the above mixture, with pectinase added at 0.20 wt%, cellulase at 0.08 wt%, and hemicellulase at 0.05 wt%. The system was heated to 42°C and enzymatically hydrolyzed at 200 rpm for 120 min. At 60 min of hydrolysis, 0.10 wt% yeast extract, 0.50 wt% trehalose, and 0.10 wt% β-glucan were added to the system. After hydrolysis, the system was heated to 55°C and held for 60 min to inactivate the enzymes, then rapidly cooled to 32°C to obtain the mixed enzymatic substrate.

[0157] 2.5 wt% of *Lactobacillus plantarum* seed culture was inoculated into the mixed enzymatic digestion substrate. The *Lactobacillus plantarum* seed culture was pre-cultured in MRS medium to the logarithmic growth phase, with a viable cell concentration of approximately 8.0 × 10⁻⁶. 8 CFU / mL of Lactobacillus plantarum seed culture was inoculated and fermented at 33°C for 24 h with a stirring speed of approximately 100 rpm. The final pH of the fermentation was controlled at 4.5 ± 0.2.

[0158] After lactic acid bacteria fermentation, the system temperature was adjusted to 30℃, and 1.5 wt% of a *Saccharomyces cerevisiae* seed culture was inoculated. The *Saccharomyces cerevisiae* seed culture was pre-cultured in YPD medium to the logarithmic growth phase, with a viable cell concentration of approximately 6.0 × 10⁻⁶. 8The inoculum was a CFU / mL Saccharomyces cerevisiae seed culture. After inoculation, fermentation was carried out at 30°C for 20 h with the stirring speed controlled at approximately 80 rpm.

[0159] After yeast fermentation, the system was heated to 55°C and held for 45 min to terminate yeast metabolism. Then, 0.05 wt% β-1,3-glucanase and 0.03 wt% mannanase were added to the system, with all enzyme additions based on the total mass of the fermentation system. The system was treated at 50°C for 4 h. After treatment, the system was heated to 85°C and held for 10 min to inactivate the enzymes, followed by cooling to room temperature.

[0160] The obtained fermentation system was centrifuged at 8000 rpm for 15 min to remove insoluble residues, and then successively filtered through a 100-mesh filter, a 0.45 μm microfilter, and a 0.22 μm filter. The mixture was then concentrated under vacuum at a temperature below 45°C to control the soluble solids content of the resulting composition to approximately 15 wt% and the pH to 4.5–4.8, thus obtaining the skin care composition containing kiwi juice.

[0161] Preparation of whitening and repairing essence Add 0.05% disodium EDTA, 5.00% glycerol, 5.00% isopentyl glycol, 2.50% nicotinamide, 1.00% PEG / PPG-14 / 7 dimethyl ether, 0.80% betaine, 0.30% inositol, and 0.50% trehalose in sequence, and stir to dissolve.

[0162] Then add 0.15% xanthan gum and 0.30% polyacrylamide dimethyl taurate, and add deionized water (to bring the total to 100%) and stir until fully hydrated.

[0163] After the system temperature drops below 40℃, add the following: 8.00% kiwi juice skincare composition; 0.50% β-glucan; 0.50% panthenol; 0.10% dipotassium glycyrrhizate; 0.50% purslane extract; 0.05% sodium polyglutamate; 0.30% p-hydroxyacetophenone; 0.50% 1,2-hexanediol; 0.10% caprylyl glycol; 0.05% ethylhexylglycerin; and 0.03% sodium phytate. Finally, adjust the pH to 5.4 using an arginine and citrate buffer system, filter, and fill to obtain the serum product.

[0164] Example 2 Except for the following differences, all other procedures were carried out in accordance with Example 1.

[0165] In the black rice bran phenolic acid release process, ferulic acid esterase and xylanase were used for treatment, without the addition of hemicellulase. Specifically, the amount of ferulic acid esterase added was 0.15 wt%, and the amount of xylanase added was 0.10 wt%.

[0166] Example 3 Except for the following differences, all other procedures were performed according to Example 1. In the peptide production step of sea buckthorn seed meal, only alkaline protease was used for single-stage enzymatic hydrolysis. The amount of alkaline protease added was 0.30 wt%. The hydrolysis temperature was 50°C. The hydrolysis time was 4 hours. No flavor protease was added.

[0167] Example 4 Except for the following differences, all other procedures were performed according to Example 1. In the yeast fermentation step, *Hansenula polymorpha* was used instead of *Saccharomyces cerevisiae*. The inoculum size was maintained at 1.5 wt%. The fermentation temperature was maintained at 30°C. The fermentation time was maintained at 20 h.

[0168] Comparative Example 1 Except for the following differences, all other procedures were performed according to Example 1. The black rice bran phenolic acid release treatment was removed. The fermentation system contained only the kiwifruit cell-wall breaking treatment and the sea buckthorn seed meal peptide treatment.

[0169] Comparative Example 2 Except for the following differences, all other procedures were performed according to Example 1. Black rice bran raw material was retained, but phenolic acid release treatment was not performed. Black rice bran was directly added to the mixed enzymatic hydrolysis system.

[0170] Comparative Example 3 Except for the following differences, all other procedures were performed according to Example 1. The sea buckthorn seed meal peptide treatment was omitted. The fermentation system contained only the kiwifruit cell wall-breaking treatment and the black rice bran phenolic acid release treatment.

[0171] Comparative Example 4 Except for the following differences, all other procedures were performed according to Example 1. Sea buckthorn seed meal was retained, but no peptide processing was performed. It was then directly added to the fermentation system after being pulverized.

[0172] Comparative Example 5 Except for the following differences, all other procedures were carried out according to Example 1. The mixed enzymatic hydrolysis treatment was omitted, and the three raw material treatments were directly introduced into the fermentation step.

[0173] Comparative Example 6 Except for the following differences, all other procedures were carried out according to Example 1. The lactic acid bacteria fermentation step was omitted, and the mixture was directly inoculated with brewer's yeast for fermentation after enzymatic hydrolysis.

[0174] Comparative Example 7 Except for the following differences, all other procedures were performed according to Example 1. The yeast fermentation step and the postbiotic release step were omitted, and only lactic acid bacteria fermentation was performed.

[0175] Comparative Example 8 The composition containing kiwifruit fermentation broth obtained in Example 1 was used. However, the sodium phytate, trehalose, and arginine buffer system were omitted from the essence formulation. The rest of the formulation remained the same.

[0176] Comparative Example 9 The essence formula is the same as in Example 1, except that the composition containing kiwi fermentation liquid is removed and the amount is made up with an equal amount of deionized water.

[0177] Comparative Example 10 The serum formula is the same as in Example 1, except that niacinamide is omitted and replaced with an equal amount of deionized water.

[0178] Comparative Example 11 The serum formula is the same as in Example 1, except that β-glucan and panthenol are not added.

[0179] Comparative Example 12 The serum formula is the same as in Example 1, except that betaine and inositol are not added.

[0180] Performance testing methods Sample setup The skincare compositions containing kiwi juice obtained in Examples 1-4 and Comparative Examples 1-12, or serums containing such compositions, were used as test samples. When testing the active ingredients, the co-fermented biogenic composition was used for detection; when evaluating whitening, repair, stability, and user experience, the corresponding serum samples were used for detection.

[0181] Unless otherwise specified, all samples were equilibrated at 25°C for 24 hours before testing and thoroughly mixed. Each test was performed in at least three parallel runs, and the average value was taken.

[0182] Test of free ferulic acid content and ferulic acid release rate This test was used to evaluate the effect of black rice bran phenolic acid release treatment on the release of bound phenolic acids.

[0183] Take 1.00 g of the sample to be tested and place it in a 50 mL centrifuge tube. Add 20 mL of 50% methanol aqueous solution and vortex mix for 2 min. Then, extract by ultrasonication in an ultrasonic cleaner for 30 min. The ultrasonic conditions are 250 W power and 25℃. After extraction, centrifuge at 8000 rpm for 10 min, collect the supernatant, and filter it through a 0.22 μm organic phase filter membrane as the test solution for free ferulic acid.

[0184] Take another 1.00 g of the same sample, add 10 mL of 2 mol / L sodium hydroxide solution, and hydrolyze for 4 h under nitrogen protection in the dark to release bound ferulic acid. After hydrolysis, adjust the pH to 2.0 with hydrochloric acid, extract three times with 10 mL of ethyl acetate each time, combine the organic phases, dry under nitrogen, and make up to 10 mL with 50% methanol. Filter through a 0.22 μm filter membrane to obtain the total ferulic acid test solution.

[0185] High-performance liquid chromatography (HPLC) was used to determine the content of ferulic acid. A C18 reversed-phase column (4.6 mm × 250 mm, 5 μm particle size) was used. Mobile phase A was 0.1% formic acid aqueous solution, and mobile phase B was methanol. The flow rate was 1.0 mL / min; the column temperature was 30℃; the detection wavelength was 320 nm; and the injection volume was 10 μL. Standard solutions of ferulic acid at concentrations of 0.5 μg / mL, 1 μg / mL, 5 μg / mL, 10 μg / mL, 25 μg / mL, and 50 μg / mL were prepared, and a standard curve was plotted.

[0186] The free ferulic acid content was calculated based on a standard curve. The ferulic acid release rate was calculated using the following formula: Ferulic acid release rate (%) = Free ferulic acid content / Total ferulic acid content × 100%.

[0187] Small molecule active peptide content test This test was used to evaluate the effectiveness of peptide processing from sea buckthorn seed meal.

[0188] Take 1.00 g of sample, add 20 mL of deionized water, mix thoroughly, and centrifuge at 10000 rpm for 10 min. Take the supernatant as the test solution. Take another identical sample and centrifuge it using an ultrafiltration centrifuge tube with a molecular weight cutoff of 5000 Da. Collect the permeate for determining the content of small molecule peptides.

[0189] The content of bioactive peptides was determined using the OPA method. 100 μL of the test solution was added to 3.0 mL of OPA colorimetric reagent, mixed well, and reacted at room temperature in the dark for 2 min. The absorbance was measured at 340 nm. A standard curve was plotted using glutathione as a standard. The content of small molecule bioactive peptides is expressed as mg / g sample.

[0190] β-glucan content test This test was used to evaluate the effects of yeast fermentation and postbiotic release treatment on the release of yeast-derived polysaccharides.

[0191] Take 1.00 g of sample, add 20 mL of deionized water, and treat in a boiling water bath for 30 min. After cooling, centrifuge at 8000 rpm for 10 min and collect the supernatant. Add an enzyme reagent composed of β-glucanase and glucosylamylase to the supernatant and react at 37℃ for 60 min to hydrolyze β-glucan into glucose. After the reaction, determine the glucose content using the glucose oxidase-peroxidase method.

[0192] A blank sample without β-glucanase treatment was set up to remove the original glucose interference in the sample.

[0193] The β-glucan content is calculated using the following formula: β-glucan content (mg / g) = (glucose content after enzymatic hydrolysis - glucose content in blank sample) × 0.9 / sample mass.

[0194] Where 0.9 is the conversion factor for glucose to dextran.

[0195] Table 1. Results of ferulic acid release rate, active peptide content, and post-biotic content tests.

[0196] DPPH free radical scavenging ability test This test is used to evaluate the antioxidant capacity of the sample.

[0197] Prepare a 0.10 mmol / L DPPH ethanol solution and store it protected from light. Take an appropriate amount of sample, dilute it with deionized water to a mass concentration of 1.0 mg / mL, mix thoroughly, and filter to obtain the test solution.

[0198] Take 2.0 mL of the test solution, add 2.0 mL of DPPH ethanol solution, mix well, and react at room temperature in the dark for 30 min. Measure the absorbance at 517 nm. Use deionized water instead of the sample as a control group, and use ethanol instead of DPPH solution as a sample blank.

[0199] The DPPH free radical scavenging rate is calculated using the following formula: DPPH clearance rate (%) = [1 - (Sample A - Blank Sample A) / Control A] × 100%.

[0200] ABTS free radical scavenging ability test This test is used to further evaluate the antioxidant capacity of the samples.

[0201] Mix an equal volume of 7 mmol / L ABTS solution with an equal volume of 2.45 mmol / L potassium persulfate solution and incubate in the dark for 12–16 h to prepare the ABTS radical stock solution. Dilute with PBS buffer before use to achieve an absorbance of 0.70 ± 0.02 at 734 nm.

[0202] Take 100 μL of sample solution, add 3.9 mL of ABTS working solution, mix well, and react at room temperature in the dark for 6 min. Measure the absorbance at 734 nm. Use PBS as a control instead of the sample.

[0203] ABTS clearance rate is calculated using the following formula: ABTS clearance rate (%) = (1 - A sample / A control) × 100%.

[0204] Tyrosinase inhibition rate test This test is used to evaluate the inhibitory effect of the sample on tyrosinase activity.

[0205] L-DOPA was used as the substrate. A pH 6.8 phosphate buffer solution, a 2 mmol / L L-DOPA solution, and a 200 U / mL mushroom tyrosinase solution were prepared.

[0206] 80 μL of phosphate buffer, 40 μL of sample solution, and 40 μL of L-DOPA solution were added sequentially to a 96-well plate, and the plate was pre-incubated at 37°C for 10 min. Then, 40 μL of tyrosinase solution was added, and the reaction was continued at 37°C for 30 min. The absorbance was measured at 475 nm.

[0207] Set up sample blank wells, i.e., do not add tyrosinase; set up control wells, i.e., use buffer instead of sample.

[0208] The tyrosinase inhibition rate is calculated using the following formula: Inhibition rate (%) = [1 - (Sample A - Blank Sample A) / Control A] × 100%.

[0209] B16-F10 cell melanin production inhibition experiment This test is used to evaluate the inhibitory effect of the sample on melanin production at the cellular level.

[0210] B16-F10 mouse melanoma cells were cultured in DMEM medium containing 10% fetal bovine serum and 1% penicillin-streptomycin at 37°C and 5% CO2. Once the cells reached the logarithmic growth phase, they were digested and seeded into 6-well plates at a density of 2 × 10⁶ cells per well. 5 One cell was cultured for 24 hours to allow it to adhere to the culture vessel.

[0211] Dilute each essence sample with serum-free medium to a final concentration of 0.5%. After removing the original medium, add medium containing the sample, with three replicates per group. Set up a model control group (containing only an equal volume of medium) and a positive control group (arbutin or kojic acid can be used as positive controls). Continue culturing for 72 hours, changing the medium containing the sample every 24 hours.

[0212] After culture, the culture medium was discarded, the cells were washed twice with PBS, and 500 μL of 1 mol / L NaOH solution was added to each well. The cells were then heated in an 80°C water bath for 1 h to fully dissolve the melanin in the cells. The absorbance of the dissolved solution was measured at 405 nm. The protein content of each well was also determined using the BCA method to correct for differences in cell number.

[0213] The relative melanin content is calculated as absorbance / protein content. The melanin production inhibition rate is calculated using the following formula: Melanin production inhibition rate (%) = (1 - relative melanin content in the sample group / relative melanin content in the model group) × 100%.

[0214] Table 2. Antioxidant capacity and whitening test results

[0215] In vitro moisturizing ability test This test is used to evaluate the hygroscopic and moisturizing properties of serum samples.

[0216] Take a clean weighing bottle and evenly spread 0.50 g of sample on the bottom. Place the weighing bottle in a constant humidity environment with a relative humidity of 81% and place it at 25℃ for 24 h. Weigh the sample and measure the mass change to calculate the moisture absorption rate.

[0217] Take another sample after it has absorbed moisture, place it in an environment with a relative humidity of 43% for another 24 hours, weigh the mass change, and calculate the moisture retention rate.

[0218] The moisture absorption rate is calculated using the following formula: Moisture absorption rate (%) = (mass after moisture absorption - initial mass) / initial mass × 100%.

[0219] The moisturizing rate is calculated using the following formula: Moisture retention rate (%) = mass after placement / mass after moisture absorption × 100%.

[0220] Centrifugal stability test This test is used to evaluate the physical stability of serum samples.

[0221] Place 50 mL of sample in a centrifuge tube and centrifuge at 4000 rpm for 30 min at 25℃. After centrifugation, observe whether the sample exhibits stratification, precipitation, flocculation, oil droplet precipitation, or color banding.

[0222] The criteria for judgment are: if the sample has no obvious stratification, no obvious precipitation, no oil separation, and no flocculation, it is judged to be qualified for centrifugal stability.

[0223] Freeze-thaw stability test This test is used to evaluate the stability of the sample under temperature cycling conditions.

[0224] Take 30 g of sample and place it in a transparent, sealed container. Place the sample at -5°C for 12 h, then transfer it to 40°C for 12 h, completing one freeze-thaw cycle. Perform five consecutive cycles.

[0225] After each cycle, observe changes in sample appearance, color, odor, layering, precipitation, and viscosity. After 5 cycles, determine sample pH, viscosity, particle size, and retention rate of active ingredients.

[0226] The criteria for judging the freeze-thaw stability are: no obvious stratification, no obvious precipitation, no obvious discoloration, pH change not exceeding 0.5, and viscosity change rate not exceeding 20%.

[0227] High-temperature accelerated stability test This test is used to evaluate the long-term storage stability of samples.

[0228] Samples were placed in a 45℃ incubator and stored in the dark for 30 days. Samples were taken and tested at 0, 7, 14 and 30 days.

[0229] The testing items include appearance, color, odor, pH, viscosity, particle size, and ferulic acid retention rate.

[0230] Viscosity was measured using a rotational viscometer at 25°C. The rotor model was selected based on the sample viscosity, and the rotational speed was 12 rpm.

[0231] The retention rate of active ingredients is calculated using the following formula: Retention rate (%) = Content after storage / Content before storage × 100%.

[0232] Table 3 Results of Moisturizing and Partial Stability Tests

[0233] Light stability test This test is used to evaluate the color and activity stability of samples under light conditions.

[0234] Take 20 g of sample and place it in a transparent glass bottle. Place the bottle in a light stability test chamber with a light intensity of 4500±500 lx and a temperature of 25℃ for 7 consecutive days. Take another identical sample and place it under light-protected conditions as a control.

[0235] After the experiment, the color change, ferulic acid retention rate, total polyphenol retention rate, and odor change were measured.

[0236] Color changes were measured using a colorimeter. a b The value is calculated, and ΔE is calculated using the following formula: ΔE = [(L -L0 ) 2 + (a -L0 ) 2 + (b -b0 ) 2 ] 1 / 2.

[0237] Among them, L0 L0 and b0 The color value of the sample before the test.

[0238] pH Adaptability Stability Test This test was used to evaluate the stability of the co-fermented biogenic composition and formulation system under different pH conditions.

[0239] Separate samples of the essence were taken, and the pH was adjusted to 4.5, 5.5, 6.5, and 7.0 using citric acid and arginine, respectively. Each pH sample was stored at 25℃ and 40℃ for 14 days.

[0240] After storage, the appearance, color, pH, viscosity, ferulic acid retention rate, total polyphenol retention rate, nicotinamide retention rate, and ΔE value were measured.

[0241] This test was used to evaluate the stabilizing effect of the arginine-citrate buffer system of the present invention on a system in which nicotinamide, phenolic acid, polyphenols and organic acids coexist.

[0242] Evaluation of patch irritation This test is used to evaluate the initial skin tolerance of serum samples.

[0243] Thirty healthy subjects, aged 18–55 years, with no obvious skin damage on the inner forearm, were selected. Approximately 0.02 g of sample was applied to a patch applicator and then placed on the inner forearm skin of the subjects for 24 hours. After removing the patch applicator, skin reactions were observed at 0.5 h, 24 h, and 48 h.

[0244] The observed indicators included erythema, edema, itching, stinging, and burning sensation. A rating scale of 0 to 4 was used, where 0 was no reaction, 1 was a mild reaction, 2 was a significant reaction, 3 was a strong reaction, and 4 was a severe reaction.

[0245] Calculate the average stimulation score. The lower the average score, the better the skin tolerance of the sample.

[0246] Evaluation of efficacy in human use This test is used to evaluate the effects of the sample on skin brightness, moisturization, and skin feel under actual use conditions.

[0247] Thirty healthy subjects, aged 18–55 years, were selected. The skin on the inner forearm of each subject was intact, without obvious erythema, lesions, dermatitis, eczema, or other skin abnormalities that might affect the test results. Subjects were not allowed to use whitening, exfoliating, or highly effective skincare products on the test area for 7 days prior to the test.

[0248] The test employed a multi-region self-control method on the inner forearm. Several test regions were divided on the inner forearm of each subject, each region measuring 3 cm × 3 cm, with a minimum distance of 1 cm between adjacent regions. Each subject had at least eight test regions to simultaneously evaluate multiple embodiments, comparative samples, and blank controls. The allocation of test samples within the test regions was randomized to minimize the impact of individual and site-specific differences on the test results.

[0249] Before the test, the subjects sat still and balanced in a constant temperature and humidity environment for 30 minutes. The ambient temperature was 22±2℃ and the relative humidity was 50±5%. The skin L value of each test area before use was measured using a skin colorimeter and used as the initial brightness value L0. The higher the L value, the higher the skin brightness.

[0250] Subjects used the test sample twice daily, once in the morning and once in the evening. Each time, the dose was 2 mg / cm³. 2 Apply the sample evenly to the corresponding test area and gently massage until absorbed. Use continuously for 28 days. During the trial, subjects should not use other whitening, exfoliating, acid-based, vitamin A-based, or other products that may affect skin color and stratum corneum condition on the test area, and should avoid prolonged sun exposure to the test area.

[0251] Skin L-values ​​were measured in each test area under the same constant temperature and humidity conditions before use, at 14 days of use, and at 28 days of use. Measurements were taken three times for each test area, and the average value was used as the L-value for that area. The change in skin brightness was calculated using the following formula: ΔL = Lt - L0 Where L0 is the skin L-value before use, and Lt is the skin L-value after 14 or 28 days of use. The larger the ΔL value, the more significant the improvement in skin brightness.

[0252] Simultaneously, the stratum corneum moisture content of each test area was measured using a stratum corneum moisture meter, and the transepidermal water loss (TEWL) value of each test area was measured using a transepidermal water loss meter. Each test area was measured three times, and the average value was taken. Increased stratum corneum moisture content indicates improved moisturizing effect, while a decreased TEWL value indicates reduced moisture loss from the skin barrier.

[0253] After 28 days of use, participants evaluated the refreshing feel, stickiness, absorption rate, stinging sensation, and overall comfort of each test sample using a questionnaire. The evaluation was based on a 5-point scale, with higher scores for refreshing feel, absorption rate, and overall comfort indicating a better skin experience; lower scores for stickiness and stinging sensation indicated less discomfort.

[0254] The test results were compared based on L value, ΔL value, stratum corneum moisture content, TEWL value, and questionnaire scores after 14 and 28 days of use for each group of samples. A blank control area was used as a baseline reference to evaluate the overall effects of each embodiment and comparative sample in terms of brightening, moisturizing, and skin feel.

[0255] Skin feel evaluation: Evaluation criteria include spreadability, hydration, absorption speed, stickiness, refreshing feel, smoothness, and overall preference. Each item is rated on a scale of 1 to 10, with 10 being the best.

[0256] The stickiness rating uses a reverse evaluation method, meaning that the higher the score, the lower the stickiness and the more refreshing the skin feel.

[0257] Table 4 Partial Test Results

[0258] Table 5 Results of pH Adaptability Stability Test

[0259] Example 1 showed the best performance in terms of in vitro moisture absorption, moisture retention, centrifugal stability, high temperature stability, freeze-thaw stability, light stability, pH adaptability, and patch irritation.

[0260] Although Examples 2-4 still have good performance, their stability, moisturizing properties and skin tolerance are slightly lower than those of Example 1 because the phenolic acid release method, peptide preparation method or yeast fermentation strain were changed respectively.

[0261] Comparative Examples 2, 4, and 5, which were not subjected to sufficient phenolic acid release, peptide preparation, or mixed enzymatic hydrolysis, all showed varying degrees of sedimentation, darkening of color, or decrease in the retention rate of active substances, indicating that the above treatment steps play an important role in forming a stable active system.

[0262] Comparative Example 8, after removing the sodium phytate, trehalose, and arginine buffer system, showed significant deterioration in high temperature, light, and pH adaptability tests, indicating that the stable system can effectively reduce the loss of polyphenols, phenolic acids, and bioactive peptides during storage.

[0263] In Comparative Example 11, the patch irritation score increased after the removal of β-glucan and panthenol, indicating that the barrier repair system can reduce skin discomfort containing organic acid ferments.

[0264] In Comparative Example 12, the removal of betaine and inositol resulted in a decrease in in vitro moisturizing ability and skin feel, indicating that betaine and inositol have a positive effect on improving moisturizing comfort and reducing stickiness.

[0265] Table 6. Evaluation results of efficacy in human use (28 days)

[0266] In Example 1, under the combined effects of the continuous fermentation system, phenolic acid release system, and peptide preparation system, the L value increased by 3.82 after 28 days, significantly higher than that of the comparative examples; simultaneously, the stratum corneum moisture increased by 42.6%, and TEWL decreased by 28.5%, indicating that it can not only improve dull skin tone but also simultaneously improve skin moisturizing ability and barrier function. Examples 2-4 also showed good brightening and moisturizing effects, but all were slightly lower than the best Example 1. Comparative examples 1 and 2 without phenolic acid release treatment, and comparative examples 5, 9, and 10 without the key fermentation step, showed significantly reduced brightness and barrier improvement effects.

[0267] Table 7. Skin feel evaluation results (28 days)

[0268] Example 1 achieved the highest scores in spreadability, hydration, absorption speed, refreshing feel, and overall preference. The inventors believe this is primarily due to the stable dispersion system formed by kiwi-derived oligopectin, sea buckthorn active peptides, and yeast-derived metagenic polysaccharides. Simultaneously, the combined effects of betaine, inositol, polyol moisturizers, and a skin-feel-modifying system contribute to the product's combination of hydration and lightness. In contrast, the comparison examples, which lacked complete fermentation or key components, tended to exhibit increased stickiness, decreased absorption speed, and reduced overall comfort.

[0269] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing a skincare composition containing kiwi juice, characterized in that, Includes the following steps: (1) Provide kiwifruit raw materials, black rice bran raw materials, and sea buckthorn seed meal raw materials for pretreatment to obtain kiwifruit treated product, black rice bran treated product, and sea buckthorn seed meal treated product; (2) Mix the kiwi fruit treatment, black rice bran treatment and sea buckthorn seed meal treatment obtained in step (1) and perform enzymatic hydrolysis. (3) The enzymatic hydrolysate obtained in step (2) is subjected to lactic acid bacteria fermentation; (4) After lactic acid bacteria fermentation, yeast fermentation is carried out to obtain the composition.

2. The preparation method according to claim 1, characterized in that, In step (1), the kiwi fruit raw material undergoes cell-wall breaking treatment, which includes one or more of the following: freeze cell-wall breaking, mechanical cell-wall breaking, and ultrasonic cell-wall breaking. The pretreatment of the black rice bran raw material includes using enzyme preparations to degrade the cell wall structure of the black rice bran; The pretreatment of the sea buckthorn seed meal raw material includes hydrolyzing the protein in the sea buckthorn seed meal using protease.

3. The preparation method according to claim 1 or 2, characterized in that, The enzymatic hydrolysis in step (2) includes one or more of pectin degradation, cellulose degradation, or hemicellulose degradation; The lactic acid bacteria used in step (3) include Lactobacillus plantarum, Lactobacillus rhamnosus, Lactobacillus paracasei, or a combination thereof; The yeast used in step (4) includes Saccharomyces cerevisiae, Kluyveromyces martensii, Hansenula anomala, or a combination thereof.

4. A skin care composition containing kiwi juice prepared by the method according to any one of claims 1 to 3.

5. A cosmetic composition, characterized in that, include: The skincare composition containing kiwi juice as described in claim 4; niacinamide; and a cosmetically acceptable carrier.

6. The cosmetic composition according to claim 5, characterized in that, The cosmetic composition further comprises β-glucan, panthenol, or a combination thereof; The cosmetic composition further comprises betaine, inositol, or a combination thereof; The cosmetic composition further comprises phytate, trehalose, or a combination thereof; The cosmetic composition further includes an amino acid buffer; The cosmetic composition further includes a polyol moisturizer.

7. The cosmetic composition according to claim 6, characterized in that, The polyol moisturizer includes glycerin, isopentyl glycol, butylene glycol, propylene glycol, or combinations thereof; The amino acid buffer includes arginine, lysine, histidine, or a combination thereof; The cosmetic composition further comprises polyglutamic acid, hyaluronic acid, cellulose thickeners, or combinations thereof; The cosmetic composition further includes isododecane, siloxane-based skin feel modifiers, or combinations thereof.

8. The cosmetic composition according to any one of claims 5-7, characterized in that, The cosmetic composition is a serum, lotion, cream, spray, mask, or freeze-dried preparation.

9. The use of the kiwi juice-containing skincare composition according to claim 4 in the preparation of cosmetics for improving dull skin tone, enhancing skin brightness, reducing oxidative damage, improving skin barrier function, and enhancing skin moisturizing ability.

10. The use of the cosmetic composition according to any one of claims 5-7 in the preparation of products for whitening and brightening, anti-oxidation, promoting keratin metabolism, improving skin barrier function and enhancing skin comfort.

Images