Mild antibacterial anti-dandruff composition and preparation method thereof

Abstract

The invention discloses a mild antibacterial anti-dandruff composition and a preparation method thereof. The composition comprises an acrylate copolymer, maltooligosaccharide and bisabolol, the mass ratio of the acrylate copolymer to the maltooligosaccharide to the bisabolol is (0.01 to 0.3) to (0.1 to 0.8) to (0.05 to 0.5); the preparation method comprises the following steps: sequentially adding the acrylate copolymer, the maltooligosaccharide and the bisabolol into water according to the mass ratio, and uniformly stirring until the materials are dissolved. The acrylate copolymer, the maltooligosaccharide and the bisabolol are blended in proportion, the maltooligosaccharide becomes a carbon source of microorganisms, malassezia is efficiently inhibited, staphylococcus epidermidis is not excessively inhibited, and meanwhile, the skin mildness and moisture retention are achieved; the bisabolol is used as a plasticizer, so that the composition of the acrylate copolymer and the maltooligosaccharide forms a uniform and tough film, the effect on malassezia and staphylococcus epidermidis is enhanced, and the anti-dandruff effect is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of cosmetics, in particular to a mild antibacterial and anti-dandruff composition and a preparation method thereof. Background Art

[0002] According to surveys, dandruff is the biggest scalp problem plaguing Chinese consumers year-round, making anti-dandruff technology a key focus in hair care product development. Currently, anti-dandruff efficacy is generally achieved by adding anti-dandruff agents to shampoo formulas.

[0003] Traditional, well-known antidandruff agents in the art, such as pyrithione zinc, piroctone olamine, climbazole, and selenium disulfide, are small, low-molecular-weight compounds with skin permeability. Their antidandruff mechanism is broad-spectrum antibacterial ingredients, primarily inhibiting Malassezia. The stronger the antibacterial effect, the greater the skin irritation. Long-term use can easily lead to scalp inflammation, such as redness and itching. New antidandruff agents released in recent years are mostly plant extract compositions, with unclear antibacterial mechanisms and less than satisfactory market acceptance of their antidandruff effects.

[0004] As time progresses, people's awareness of health continues to rise, extending their focus from the facial skin barrier to the scalp barrier. A growing body of research indicates that scalp problems are closely linked to the microbial barrier formed by diverse bacterial communities. Scalp microecological care technology has become a key focus in hair care product development. Common scalp bacteria include Staphylococcus aureus and Malassezia. Among these Staphylococci, there's Staphylococcus epidermidis, which breaks down triglycerides in sebum into fatty acids and glycerol. The fatty acids produced keep the scalp slightly acidic, inhibiting the growth of Staphylococcus aureus, which triggers inflammatory reactions, thereby protecting the scalp. Glycerol, on the other hand, moisturizes the scalp and maintains its barrier function. Therefore, Staphylococcus epidermidis is considered a beneficial scalp bacterium. Malassezia, another scalp fungus, is considered a major culprit in dandruff. It breaks down triglycerides in sebum into saturated and unsaturated fatty acids. Unsaturated fatty acids are irritating to the scalp, directly causing redness, itching, inflammation, and excessive dandruff. Furthermore, the scalp has the most sebaceous glands in the body, and sweat glands are second only to the hands and feet. Therefore, the scalp secretes more sebum and sweat than other parts of the body. The accumulation of sebum and sweat leads to a proliferation of microorganisms, making the scalp more susceptible to microbial imbalance than other parts of the body.

[0005] Existing patent CN118557469A discloses a mild anti-dandruff composition based on an acrylic acid (ester) / dimethylaminoethyl methacrylate copolymer. The ability of polymer-based anti-dandruff agents to effectively combat dandruff on the scalp relies primarily on the polymer's film-forming properties. The resulting film covers the scalp surface and interacts with the scalp's microbial flora. However, the patent does not describe how the polymer anti-dandruff agent acts on the scalp, nor does it provide methods for enhancing its effectiveness.

[0006] In summary, existing anti-dandruff ingredients have the problem of not being able to take into account both dandruff removal and scalp protection. Summary of the Invention

[0007] The present invention aims to provide a mild antibacterial anti-dandruff composition and a preparation method thereof. The present invention has a good anti-dandruff effect and does not damage the scalp.

[0008] The technical solution of the present invention is a mild antibacterial anti-dandruff composition, comprising an acrylate copolymer containing an amino group in the side chain, oligomaltose and bisabolol; the mass ratio of the acrylate copolymer containing an amino group in the side chain, oligomaltose and bisabolol is 0.01-0.3:0.1-0.8:0.05-0.5.

[0009] In the aforementioned mild antibacterial and anti-dandruff composition, the mass ratio of the acrylic acid ester copolymer containing amino groups in the side chain, maltooligosaccharide and bisabolol is 0.03-0.2:0.5-0.8:0.1-0.3.

[0010] In the aforementioned mild antibacterial anti-dandruff composition, the acrylic acid ester copolymer containing amino groups in the side chain is an acrylic acid (ester) / dimethylaminoethyl methacrylate copolymer, and has a molecular weight of 50,000-150,000.

[0011] In the aforementioned mild antibacterial and anti-dandruff composition, the maltooligosaccharide is maltotetraose.

[0012] A method for preparing a mild antibacterial and anti-dandruff composition comprises the following steps: mixing an amino group-containing acrylic acid ester copolymer and bisabolol in a mass ratio until the amino group-containing acrylic acid ester copolymer is completely dispersed; adding the mixture into water; stirring the mixture evenly; and then adding malto-oligosaccharide; stirring the mixture evenly until the mixture is completely dissolved.

[0013] Compared with the prior art, the present invention mixes an acrylate copolymer containing an amino group in its side chain, oligomaltose, and bisabolol in a certain proportion to form an anti-dandruff composition for removing dandruff. Oligomaltose can serve as a carbon source for microorganisms, effectively inhibiting Malassezia without excessively inhibiting Staphylococcus epidermidis, while also being mild and moisturizing to the skin. Bisabolol can act as a plasticizer to form a uniform and tough film from the composition of the acrylate copolymer containing an amino group in its side chain and oligomaltose, thereby enhancing its effect on Malassezia and Staphylococcus epidermidis, thereby further improving the anti-dandruff efficacy.

[0014] The cationic groups in acrylate / dimethylaminoethyl methacrylate copolymers can interact with anions on bacterial or fungal cell membranes, disrupting them and preventing their survival. A molecular weight of 50,000-150,000 allows the polymer to penetrate the bacterial or fungal cell wall and reach the membrane, but it lacks the selective antibacterial effect against harmful scalp bacteria. Furthermore, a molecular weight of 50,000-150,000 prevents skin permeability, ensuring safety and gentleness.

[0015] Maltotetraose can serve as a carbon source for many microorganisms, promoting their growth and reproduction. If the environmental conditions are suitable, maltose may have a significant growth effect on microorganisms. Not all microorganisms can utilize maltose, so its growth effect may be somewhat selective. Different types or strains of microorganisms have different efficiency and ability to utilize maltose.

[0016] Bisabolol is a sesquiterpene alcohol with a certain fat solubility and a plasticizing effect on polymers. By adding bisabolol, the composition of the high-molecular anti-dandruff agent and oligomaltose forms a uniform and tough film, enhancing its effect on Malassezia and Staphylococcus epidermidis, thereby improving the anti-dandruff efficacy. DETAILED DESCRIPTION

[0017] The present invention will be further described below with reference to the examples, but they are not intended to limit the present invention.

[0018] Example 1. A mild antibacterial anti-dandruff composition comprising an acrylic acid ester copolymer containing amino groups in its side chains, maltooligosaccharide, and bisabolol;

[0019] The acrylic acid ester copolymer containing amino groups in the side chain is an acrylic acid (ester) / dimethylaminoethyl methacrylate copolymer with a molecular weight of 50,000-150,000;

[0020] The maltooligosaccharide is maltotetraose;

[0021] The acrylic acid ester copolymer is an acrylic acid (ester) / dimethylaminoethyl methacrylate copolymer, maltotetraose and bisabolol in a mass ratio of 0.01:0.1:0.2.

[0022] A method for preparing a mild antibacterial and anti-dandruff composition comprises the following steps: mixing an amino group-containing acrylic acid ester copolymer and bisabolol in a mass ratio until the amino group-containing acrylic acid ester copolymer is completely dispersed; adding the mixture into water; stirring the mixture evenly; and then adding malto-oligosaccharide; stirring the mixture evenly until the mixture is completely dissolved.

[0023] Raw material information:

[0024] Acrylates / dimethylaminoethyl methacrylate copolymer, trade name Poly-D-Fi, is from Nippon Shokubai Co., Ltd.

[0025] Maltotetraose, sold under the trade name LEOGARD MT, is from Lion Specialty Chemicals Co., Ltd.

[0026] Bisabolol, trade name ALPHA-BISABOLOL 85, is from ATINA ATIVOS NATURAIS LTDA

[0027] Example 2. A mild antibacterial anti-dandruff composition, having the same other features as Example 1, except that the acrylic acid ester copolymer is an acrylic acid (ester) / dimethylaminoethyl methacrylate copolymer, and the mass ratio of maltotetraose to bisabolol is 0.036:0.2:0.15.

[0028] Example 3. A mild antibacterial anti-dandruff composition, having the same other features as Example 1, except that the acrylic acid ester copolymer is an acrylic acid (ester) / dimethylaminoethyl methacrylate copolymer, and the mass ratio of maltotetraose to bisabolol is 0.15:0.11:0.05.

[0029] Example 4. A mild antibacterial anti-dandruff composition, having the same other features as Example 1, except that the acrylic acid ester copolymer is an acrylic acid (ester) / dimethylaminoethyl methacrylate copolymer, and the mass ratio of maltotetraose to bisabolol is 0.2:0.5:0.1.

[0030] Example 5. A mild antibacterial anti-dandruff composition, having the same other features as Example 1, except that the acrylic acid ester copolymer is an acrylic acid (ester) / dimethylaminoethyl methacrylate copolymer, and the mass ratio of maltotetraose to bisabolol is 0.3:0.8:0.3.

[0031] Experimental comparison and verification

[0032] Comparative Example 1: Other features are the same as those of Example 1, except that the acrylic acid ester copolymer is an acrylic acid (ester) / dimethylaminoethyl methacrylate copolymer, and the mass ratio of maltotetraose to bisabolol is 0.009:0.8:0.6;

[0033] Comparative Example 2: Other features are the same as those of Example 1, except that the acrylic acid ester copolymer is an acrylic acid (ester) / dimethylaminoethyl methacrylate copolymer, and the mass ratio of maltotetraose to bisabolol is 0.009:1.8:0.005.

[0034] Comparative Example 3: Other features are the same as those of Example 1, except that the acrylic acid ester copolymer is an acrylic acid (ester) / dimethylaminoethyl methacrylate copolymer, and the mass ratio of maltotetraose and bisabolol is 0.2:0:0.2.

[0035] Comparative Example 4: Other features are the same as those of Example 1, except that the acrylic acid ester copolymer is an acrylic acid (ester) / dimethylaminoethyl methacrylate copolymer, and the mass ratio of maltotetraose and bisabolol is 0.5:0.5:1.

[0036] Comparative Example 5: Other features are the same as those of Example 1, except that the acrylic acid ester copolymer is an acrylic acid (ester) / dimethylaminoethyl methacrylate copolymer, and the mass ratio of maltotetraose and bisabolol is 0.3:0.02:0.

[0037] Comparative Example 6: Other features are the same as those of Example 1, except that the acrylic acid ester copolymer is an acrylic acid (ester) / dimethylaminoethyl methacrylate copolymer, and the mass ratio of maltotetraose and bisabolol is 0.1:0:0.

[0038] Comparative Example 7: Other features are the same as those of Example 1, except that the acrylic acid ester copolymer is an acrylic acid (ester) / dimethylaminoethyl methacrylate copolymer, and the mass ratio of maltotetraose and bisabolol is 1:0:0.

[0039] Comparative Example 8: Other features are the same as those of Example 1, except that the acrylic acid ester copolymer is an acrylic acid (ester) / dimethylaminoethyl methacrylate copolymer, and the mass ratio of maltotetraose and bisabolol is 0:0.1:0.

[0040] Comparative Example 9: Other features are the same as those of Example 1, except that the acrylic acid ester copolymer is an acrylic acid (ester) / dimethylaminoethyl methacrylate copolymer, and the mass ratio of maltotetraose and bisabolol is 0:1:0.

[0041] Comparative Example 10: Other features are the same as those of Example 1, except that the acrylic acid ester copolymer is an acrylic acid (ester) / dimethylaminoethyl methacrylate copolymer, and the mass ratio of maltotetraose and bisabolol is 0:0:0.1.

[0042] Comparative Example 11: Other features are the same as those of Example 1, except that the acrylic acid ester copolymer is an acrylic acid (ester) / dimethylaminoethyl methacrylate copolymer, and the mass ratio of maltotetraose and bisabolol is 0:0:1.

[0043] Comparative Example 12: Other features are the same as those of Example 1, except that the acrylic acid ester copolymer is an acrylic acid (ester) / dimethylaminoethyl methacrylate copolymer, and the mass ratio of maltotetraose and bisabolol is 0.1:0.1:0.

[0044] Comparative Example 13: Other features are the same as those of Example 1, except that the acrylic acid ester copolymer is an acrylic acid (ester) / dimethylaminoethyl methacrylate copolymer, and the mass ratio of maltotetraose and bisabolol is 0.1:0:0.1.

[0045] The embodiments and comparative examples were tested, and the specific test methods and results are shown below.

[0046] 1. Film forming test

[0047] The samples were added to a culture dish and dried at 70°C for 24 hours. The film-forming properties were observed. The results are shown in the following table.

[0048] Table 1 Film forming test results

[0049]

[0050]

[0051] The results of film-forming experiments show that acrylic acid (ester) / dimethylaminoethyl methacrylate copolymer has film-forming properties but can only form hard and brittle films. Maltotetraose and bisabolol alone do not have film-forming properties, but both have a certain degree of plasticity. Among them, bisabolol has higher plasticity for polymers. Optimizing the addition amount of bisabolol can help the combination of polymer anti-dandruff agents and oligomaltose form a flexible film.

[0052] 2. Bacterial activity test

[0053] Reagents used for bacterial activity test:

[0054] Staphylococcus epidermidis, trade name Staphylococcus epidermidis NBRC12993, from the National Institute of Technology and Evaluation;

[0055] Malassezia, trade name Malassezia furfur NBRC0656, is from the National Institute of Technology and Evaluation.

[0056] Staphylococcus epidermidis culture medium, trade name NBRC802, contains 1% polypeptone, 0.2% yeast extract, 0.1% magnesium sulfate, and 98.7% water, and is obtained from the National Institute of Technology and Evaluation.

[0057] Malassezia culture medium, trade name YM medium, contains 1% glucose, 0.5% peptone, 0.3% yeast extract, 0.3% malt extract, and 97.9% water, and is obtained from the National Institute of Technology and Evaluation.

[0058] Staphylococcus epidermidis was cultured in NBRC802 medium and Malassezia species in YM medium at 37°C. The bacterial cultures were diluted to an OD600 absorbance of 0.08-0.13 using a MiniPhoto518R spectrophotometer. Each culture was then diluted 100-fold to serve as the experimental culture medium for bacterial growth activity testing. 180 μl of the bacterial culture was added to the film-forming test sample at 37°C and incubated for 24 hours. The OD600 absorbance of the culture medium was measured using an Infinite 200Pro MPlex spectrophotometer. The absorbance of the mixed culture solution after adding sterile water was compared to the blank control. A higher absorbance than the blank control indicated enhanced bacterial activity, while a lower absorbance than the blank control indicated inhibition.

[0059] Table 2 Bacterial activity test results

[0060]

[0061] The results of bacterial activity tests showed that the combination of the optimized ratio of the polymer anti-dandruff agent and maltotetraose effectively inhibited Malassezia without excessively inhibiting Staphylococcus epidermidis. Example 5 exhibited a higher inhibitory effect on Malassezia than Comparative Example 5, which did not contain the plasticizer bisabolol. While Example 5 did not inhibit Staphylococcus epidermidis, Comparative Example 5 did. This indicates that forming a flexible film can enhance the inhibitory effect of the polymer anti-dandruff agent on Malassezia while helping maltotetraose to better promote the growth of Staphylococcus epidermidis.

[0062] Comparative Examples 8-13 show that acrylic acid (ester) / dimethylaminoethyl methacrylate copolymer has a strong antibacterial effect on Staphylococcus epidermidis and Malassezia, maltotetraose has a strong promoting effect on Staphylococcus epidermidis and Malassezia, and bisabolol has no obvious effect on the activity of Staphylococcus epidermidis and Malassezia; acrylic acid (ester) / dimethylaminoethyl methacrylate copolymer and maltotetraose can promote the activity of Staphylococcus epidermidis and inhibit the activity of Malassezia; acrylic acid (ester) / dimethylaminoethyl methacrylate copolymer and bisabolol can increase the antibacterial effect of acrylic acid (ester) / dimethylaminoethyl methacrylate copolymer through film formation after compounding.

[0063] From the above analysis, it can be seen that the present application can effectively inhibit Malassezia but not excessively inhibit Staphylococcus epidermidis, and through the plasticizer, it can form a flexible film so that it can come into more complete contact with the bacteria on the scalp and exert its effect more effectively.

Claims

1. A mild antibacterial anti-dandruff composition, characterized in that: The invention comprises an acrylic acid ester copolymer containing an amino group in the side chain, oligomaltose and bisabolol; the mass ratio of the acrylic acid ester copolymer containing an amino group in the side chain, oligomaltose and bisabolol is 0.01-0.3:0.1-0.8:0.05-0.

5.

2. A mild antibacterial anti-dandruff composition according to claim 1, characterized in that: The mass ratio of the acrylic acid ester copolymer containing amino groups in the side chain, oligomaltose and bisabolol is 0.03-0.2:0.5-0.8:0.1-0.

3.

3. A mild antibacterial anti-dandruff composition according to claim 1, characterized in that: The acrylic acid ester copolymer containing amino groups in the side chain is an acrylic acid (ester) / dimethylaminoethyl methacrylate copolymer with a molecular weight of 50,000-150,000.

4. A mild antibacterial anti-dandruff composition according to claim 1, characterized in that: The maltooligosaccharide is maltotetraose.

5. A method for preparing a mild antibacterial antidandruff composition according to any one of claims 1 to 4, characterized in that: The amino group-containing acrylic acid ester copolymer and bisabolol are mixed in a mass ratio until the amino group-containing acrylic acid ester copolymer is completely dispersed, and then added into water and stirred evenly. Then, oligomaltose is added and stirred evenly until it is completely dissolved.

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