TWI884799B - Nanostructured lipid carrier containing hydroxyresveratrol - Google Patents

Abstract

The present invention relates to a nanostructured lipid carrier containing hydroxyresveratrol. The nanostructured lipid carrier composed of specific ingredients and proportions can effectively coat hydroxyresveratrol, so that hydroxyresveratrol can be effectively delivered to the deep layers of the skin to enhance the whitening effect.

Description

Nanostructured lipid carrier containing hydroxyresveratrol

The present invention relates to a nanostructured lipid carrier containing hydroxyresveratrol, and in particular to a nanostructured lipid carrier containing hydroxyresveratrol that can effectively deliver hydroxyresveratrol to the deep layers of the skin.

In recent years, with the rapid development of technology, the modern cosmetics industry has also ushered in an unprecedented change. With the unremitting efforts of many beauty brands, beauty care is no longer limited to concealing and retouching, but is gradually developing towards bringing health and translucence to the skin, especially the whitening and brightening function, which has become one of the focuses of attention in the current market.

Market analysis data from the past five years shows that the demand for whitening and brightening products has continued to grow; consumers' demand for skin color optimization continues to increase, which also reflects modern people's pursuit of healthy and beautiful skin and their emphasis on self-confidence.

Studies have shown that about two-thirds of the world's plants have medicinal value, and many plant extracts are used in health research. Among them, white mulberry ( Morus alba ) is a small to medium-sized deciduous tree of the genus Morus, widely distributed in China, Taiwan, and Ryukyu. Its trunk mainly contains hydroxyresveratrol and resveratrol. Hydroxyresveratrol can be separated and purified through extraction and purification; while wild jackfruit ( Artocarpus lakoocha , also known as monkey fruit, is also a plant of the Moraceae family and is grown in Southeast Asian countries. It has biological properties such as antiviral, antibacterial, wound healing, anti-inflammatory, and anti-cancer. It also contains active compounds such as artocarpin, polyphenols, and flavonoids. Hydroxyversatil can also be separated and purified through extraction.

As a gift from nature, the extracts of mulberry plants are mild in nature and suitable for all skin types. They reduce irritation to the skin, making them the first choice for whitening in many people's minds. White mulberry extracts contain rich antioxidant ingredients, especially hydroxyresveratrol, which can effectively inhibit the production of melanin and reduce the formation of skin spots. Baobab is rich in polyphenols and flavonoids, and also has whitening, antioxidant, and anti-inflammatory effects, keeping the skin even and translucent. At the same time, it also has excellent soothing and repairing effects, which can effectively relieve skin discomfort caused by environmental pressure and daily resistance to external aggression, and enhance the overall radiance of the skin.

However, although moraceae plant extracts have excellent whitening effects, they often have difficulty penetrating into the deep layers of the skin, even into the dermis, which greatly reduces the whitening effect. Therefore, it is necessary to find a method that can make moraceae plant extracts penetrate into the deep layers of the skin more easily and improve the whitening effect.

In view of the fact that the whitening effect of mulberry plant extracts cannot easily penetrate deep into the skin, resulting in poor whitening effect, the inventors have finally developed a nanostructured lipid carrier that can be used to improve the poor delivery effect of mulberry plant extracts after unremitting research and experiments.

Nanocarrier technology has attracted much attention in the fields of drug delivery and cosmetics care in recent years. By encapsulating the extract of Moraceae plants in a nanostructured lipid carrier (NLC), the extract of Moraceae plants can be efficiently delivered to the deep layers of the skin; this carrier technology not only brings into play the mild nature of Moraceae plant extracts and their ability to inhibit melanin production, making their whitening effect more efficient, providing more possibilities for the pursuit of translucent and bright skin.

On the other hand, hydroxyresveratrol in Moraceae plant extracts has the disadvantages of being easily oxidized, unstable, having low water solubility and low bioavailability, so many current studies have used nanocarriers to encapsulate it for use; however, in the existing technology, although nanostructured lipid carriers (NLCs) can be used to encapsulate hydroxyresveratrol, their stability is poor and can only be stored at 4°C for a maximum of 12 months. Moreover, the particle size of the carrier will gradually increase over time and cannot be stored at room temperature for a long time.

The purpose of the present invention is to provide a nanostructured lipid carrier containing hydroxyresveratrol. The nanostructured lipid carrier composed of specific ingredients and proportions can effectively encapsulate the moraceae plant extract containing hydroxyresveratrol and has excellent stability. It can also effectively deliver the moraceae plant extract to the deep layers of the skin to enhance the whitening effect.

Below, the specific embodiments are described in detail with the attached drawings, so that it is easier to understand the purpose, technical content, features and effects achieved by the present invention.

The following diagram further illustrates the present invention:

Figure 1 is a diagram showing the ratio of hydroxyresorvate alcohol content in the stable formula of nanostructured lipid carriers containing hydroxyresorvate alcohol after being placed at different temperatures for 50 days; Figure 2 is a diagram showing the ratio of hydroxyresorvate alcohol content in hydroxyresorvate alcohol coated with nanostructured lipid carriers and hydroxyresorvate alcohol not coated with nanostructured lipid carriers after being placed at different temperatures for 90 days. Schematic diagram of alcohol content ratio; Figure 3 is a schematic diagram of the coating rate of the raw materials encapsulated in the stable formula group of the nanostructured lipid carrier containing hydroxyl resveratrol; Figure 4 is a schematic diagram of the particle size distribution of the nanostructured lipid carrier in the stable formula group of the nanostructured lipid carrier containing hydroxyl resveratrol; Figure 5 is a schematic diagram of the results of the percutaneous absorption experiment.

In order to help the review committee understand the technical features, content and advantages of the invention and the effects that can be achieved more clearly, the invention is described in detail as follows with the accompanying drawings and in the form of embodiments. The drawings used are only for illustration and auxiliary instructions, and may not be the true proportions and precise configurations after the implementation of the invention. Therefore, the proportions and configurations of the attached drawings should not be interpreted to limit the scope of rights of the invention in actual implementation.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the meanings commonly understood by those of ordinary skill in the art to which the present invention belongs. It will be further understood that those terms as defined in commonly used dictionaries should be interpreted as having meanings consistent with their meanings in the context of the relevant art and the present invention, and will not be interpreted as idealized or overly formal meanings unless expressly so defined herein.

Example 1 Preparation of nanostructured lipid carriers containing hydroxyresveratrol

Common methods for preparing NLC include high (low) shear homogenization, ultrasonic vibration, thin film contact technology, emulsification solvent volatility and high pressure homogenization. The present invention uses a combination of high shear homogenization, high pressure homogenization and low shear homogenization to prepare the desired nanostructured lipid carrier.

0.1-0.5wt% of a mulberry plant extract containing hydroxyveratrol (white mulberry extract or monkey fruit extract) is dissolved in an oil phase solution, wherein the oil phase solution comprises: 2-8wt% of cetyl palmitate, 2-5wt% of caprylic/capric triglycerides, 0-4.5wt% of sorbitan monolaurate (SPAN20) or 0-1.875wt% of lecithin or 0-3wt% of decyl glucoside is added thereto; and the aqueous phase solution comprises: 0-6wt% of polysorbate 80 (Tween80) and 79.5-89.075wt% of water.

The oil phase solution and the water phase solution are heated to 60°C, 70°C, 80°C, and 90°C respectively, and a high shear homogenization method is performed; the oil phase solution is added to the water phase solution for pre-emulsification, and a high-speed homogenizer is used for emulsification at a speed of 4000-12000RPM for 3-10 minutes to obtain a pre-emulsified mixture; wherein, after quality screening, the optimal pre-emulsification conditions are 70°C, a speed of 8000RPM, and a pre-emulsification time of 3 minutes.

Next, the high-pressure homogenization method is used to transfer the above-mentioned pre-emulsified mixtures to a high-pressure homogenizer (model SPX APV2000). The homogenization pressure is set at 100~1000bar, and 4~10 cycles of homogenization are performed. The temperature is maintained at 60~90℃ to obtain a high-pressure treated mixture. Among them, after quality screening, the optimal high-pressure homogenization conditions are 65℃, pressure 500bar, and 5~6 cycles.

Finally, the low shear homogenization method was used to cool the mixtures treated with high pressure in a 4°C ice bath and transfer them to a high-speed homogenizer. The mixtures were re-emulsified at a speed of 1000-12000 RPM, and the temperature was tested to drop from 65-70°C to 15-20°C, thereby obtaining a nanostructured lipid carrier containing hydroxyresveratrol. After quality screening, the optimal emulsification conditions were cooling in a 4°C ice bath, a speed of 4000 RPM, and emulsification for at least 5 minutes until the temperature reached 15-20°C. The raw material formulas of each group and the state of the nanostructured lipid carrier containing hydroxyresveratrol are shown in Table 1.

Table 1

As shown in Table 1, the nanostructured lipid carriers containing hydroxyresveratrol in groups E1 and E2 showed precipitation after preparation, while groups E3, E4, E5, E8, E9, E10, E11, and E12 showed stratification after preparation. Only groups E6 and E7 showed a uniform and stable state. Therefore, the stable formula groups after screening were E6 and E7, and these two groups were used for various experiments.

Example 2 Stability screening experiment

The stable formula groups E6 and E7 obtained in Example 1 were screened for stability. The nanostructured lipid carriers containing hydroxyresveratrol in groups E6 and E7 were placed at 5°C, 25°C and 45°C for 50 days, respectively, and the content of hydroxyresveratrol was determined by HPLC. The results are shown in Figure 1. As can be seen from the figure, the stable formula groups E6 and E7 have a stable stability of hydroxyresveratrol at 45°C. After being stored at ℃ for 50 days, the relative contents of hydroxyresveratrol were 83.8% and 65.4% compared with those on day 0. The hydroxyresveratrol content in the E6 group was significantly higher than that in the E7 group. The reduction in the E7 group was about 2.1 times that of the E6 group ((100-65.4)/(100-83.8)=2.1), so the E6 group was finally selected for subsequent testing.

Next, the stability of hydroxyresorvastatin dissolved in glycerol was compared between the group without nanostructured lipid carrier coating and the group with nanostructured lipid carrier coating. After the two groups were placed at 5℃, 25℃ and 45℃ for 90 days, the content of hydroxyresorvastatin was determined by HPLC. The results are shown in Figure 2. As can be seen from the figure, the nanostructured lipid carrier coated E6 group The lipid carrier-encapsulated E6 group can effectively protect hydroxyresveratrol from high temperature and oxidation. Its relative content of hydroxyresveratrol is higher than that of the unencapsulated group, which is about 13.4% higher than that of the unencapsulated group (83.0-69.6=13.4). This proves that the nanostructured lipid carrier formula of the E6 group has the ability to protect the encapsulated active ingredients.

Example 3: Coverage rate and particle size distribution experiment

The E6 group was tested for encapsulation efficiency. 100 μL of the E6 group was placed in a high-speed centrifuge tube feed tank (model Vivaspin 500) and centrifuged at 12,000 RPM for 60 minutes using a refrigerated high-speed centrifuge (model Hitachi CF16RN). The lower layer of liquid was then extracted and the content of the moraceae plant extract containing hydroxyresveratrol (i.e., the encapsulated raw material) was detected using HPLC. The calculation formula is as follows:

As shown in Figure 3, the coverage rate of the Moraceae plant extract containing hydroxyresveratrol coated in the E6 group is as high as 99.9999%, which can be regarded as complete coverage.

Next, 100 μL of the E6 group was taken and added to 900 μL of secondary water (ddH ₂ O) to mix evenly. The mixture was then transferred to the sample tank and the particle size distribution experiment was conducted using a nanoparticle size and interface potential meter (Malvern Nano ZS).

As shown in Figure 4, the average particle size of the nanostructured lipid carriers in the E6 group is 181.8nm, and the particle size distribution quality is assessed as good.

Example 4 Percutaneous absorption experiment

The E6 group was applied to cosmetics such as creams and serums, and compared with the active ingredients without nanostructured lipid carriers (i.e. unencapsulated Moraceae plant extracts containing hydroxyresveratrol).

First, the formulas of the cream and the essence are shown in Tables 2 and 3, wherein the base agent of the cream group comprises oil, emulsifier, water, moisturizer and preservative, the oil is selected from at least one of isotridecyl isononanoate, pentaerythrityl tetraethylhexanoate and camellia oleifera seed oil, the emulsifier is selected from polyacrylate-13, polyisobutylene, polysorbate-20, sodium arcylates copolymer, lecithin and sorbitan isostearate. The moisturizing agent is selected from at least one of 1,3-propylene glycol, glycerol, 1,2-propylene glycol, polyethylene glycol-400 (PEG-400), polyacrylate-13 and polyisobutylene; the preservative is selected from at least one of 1,2-hexanediol, caprylhydroxamic acid, hydroxyacetophenone, dipropylene glycol and caprylyl glycol. The base formulation of the essence group comprises water, a skin conditioning agent, a thickener, a preservative and a moisturizer, wherein the skin conditioning agent is selected from at least two of niacinamide, dipotassium glycyrrhizate, propanediol and ascorbyl glucoside, the thickener is selected from at least two of sodium arcylates copolymer, lecithin, xanthan gum and sodium hyaluronate, the preservative is selected from propanediol, 1,2-hexanediol, caprylhydroxamic acid, and the like. The moisturizer is selected from at least two of propanediol, glycerol, propylene glycol, polyethylene glycol-400 (PEG-400), polyacrylate-13 and polyisobutylene.

Next, we used Strat-M ^® bionic skin as a simulation sample, and simulated the penetration of whitening ingredients into the skin through the Franz Cell vertical diffusion tank system. This system is specially used to perform drug absorption and release tests, and is also applicable to various types of samples, including liquids, lotions, gels, ointments and creams. According to the OECD429 guidelines, we added 30 mg of the test substance (i.e., E29, E32, ES1 and ES2 groups) to the upper supply tank. After 6 hours of simulated penetration, the experimental conditions were 37.5°C and 600RPM, and the following contents were collected individually. All samples were analyzed by HPLC to measure their contents:

1. Data inside the Strat-M ^® bionic skin (indicates that ingredients with whitening effects penetrate and accumulate in the surface of the skin).

2. Data of the lower buffer liquid (representing that the whitening ingredients penetrate the dermis and reach the lower skin tissue). All samples were analyzed by high performance liquid chromatography to measure their content.

The above experimental results are shown in Figure 5. It can be seen from the figure that in the E29 group, which is a general cream, about 35% of the whitening ingredients entered the epidermis, but failed to effectively penetrate the Strat-M ^® bionic skin and reach the lower buffer solution. In contrast, the E32 group containing NLC-encapsulated whitening ingredients in the cream has a total penetration rate (total absorption) of about 36.6%, of which the content in the membrane is about 31.2%, and the content in the lower buffer solution is about 5.4%.

On the other hand, it can be seen from the figure that in the ES1 group, which is a general essence, about 36.8% of the whitening ingredients enter the epidermis and are also unable to effectively penetrate the Strat-M ^® bionic skin and reach the lower buffer solution; however, the ES2 group, which contains NLC-encapsulated whitening ingredients in the essence, has a total penetration rate (total absorption) of about 36.7%, of which the content in the membrane is about 32.3% and the content in the lower buffer solution is about 4.4%.

The above experimental results show that the E29 and ES1 groups without NLC-encapsulated whitening ingredients cannot effectively penetrate the Strat-M ^® bionic skin; while the E33 and ES2 groups with NLC-encapsulated whitening ingredients can penetrate the surface of the Strat-M ^® bionic skin to the underlying skin tissue. The content of the whitening ingredients that penetrated is about 4.4~5.4%, which is converted into a relative penetration of 11.98% (4.4/36.7*100)-14.75% (5.4/36.6*100) and can effectively penetrate into the underlying liquid. It can be seen that the whitening ingredients are coated with NLC so that they can effectively penetrate into the underlying skin tissue, act on the dermis layer of the skin, achieve percutaneous absorption, and enhance the whitening effect.

In summary, the nanostructured lipid carrier containing hydroxyresveratrol of the present invention has good stability, coverage rate and particle size distribution. When used in cosmetics such as creams and essences, it can indeed allow the encapsulated active ingredients to penetrate deep into the underlying skin tissue, so that the active ingredients can play their role more efficiently.

Those skilled in the art to which the present invention belongs can understand from the above content that the present invention can be exemplified in other specific forms without changing the technical concepts or essential features of the present disclosure. In this regard, the exemplary aspects disclosed herein are only used for exemplary purposes and should not be interpreted as limiting the scope of the present disclosure. On the contrary, the present disclosure tends to cover not only such exemplary aspects, but also various changes, modifications, equivalents, and other aspects that may be included in the spirit and scope of the present invention as defined in the scope of the attached patent application.

Claims (4)

A nanostructured lipid carrier containing hydroxy resveratrol, wherein the nanostructured lipid carrier containing hydroxy resveratrol comprises the following components: 0.3wt% of a Moraceae plant extract containing hydroxy resveratrol; 5wt% of cetyl palmitate; 5wt% of caprylic/capric triglyceride; 4.5wt% of sorbitan monolaurate; 3.5wt% of polysorbate 80; and 81.7wt% of water. The nanostructured lipid carrier containing hydroxyresveratrol as described in claim 1, wherein the Moraceae plant extract is selected from white mulberry extract or monkey fruit extract. The nanostructured lipid carrier containing hydroxyresveratrol as described in claim 1 or claim 2, wherein the nanostructured lipid carrier containing hydroxyresveratrol is applied in a cream or an essence, and based on the total weight of the cream or the essence, the nanostructured lipid carrier containing hydroxyresveratrol accounts for 50wt%. The nanostructured lipid carrier containing hydroxyresveratrol as described in claim 3, wherein when the nanostructured lipid carrier containing hydroxyresveratrol is applied to the cream or the essence, the relative penetration of the nanostructured lipid carrier containing hydroxyresveratrol into the underlying skin tissue is 11.98-14.75% based on the total absorption of the skin.